Pediatrics

WASHINGTON– Gene therapy for the treatment of rare diseases continues to develop and new products are entering the pipeline; however, more work is needed to make the gene therapy experience easier on patients and their families, according to members of a panel at the NORD Rare Diseases & Orphan Product Breakthrough Summit, held by the National Organization for Rare Disorders.

Companies developing gene therapy cite their main challenges as identifying patients, developing clinical trials, coordinating treatment and supporting families, managing reimbursement, and manufacturing the treatment, said Mark Rothera, president and CEO of Orchard Therapeutics, developer of ex vivo autologous hematopoietic stem cell gene therapy.

For families of patients with rare diseases who are undergoing gene therapy, challenges include struggles such as language barriers, lack of wifi, and separation from other family members for extended periods, according to Amy Price, mother of a gene therapy recipient, as well as principal consultant to Rarallel and an advocate for metachromatic leukodystrophy.

Ms. Price cited a survey she conducted of families with children who underwent gene therapy. She collected data from 16 families about their initial visit as part of a gene therapy trial; the trials included 14 families in Milan; 1 in Bethesda, Md.; and 1 in Paris. The average age of the patients at the start of the trial was 3 years, with a range of 8 months to 11 years. The trials were conducted between 1990 and 2018.

Families participating in the trials spent an average of 5.5 months in the city where the trial was conducted, and an average of 48 days in an isolation ward with their child at the start of the study.

The five biggest challenges were financial well-being (cited by 60% of survey respondents), social isolation/being away from support system (60%), fear of the unknown/long-term treatment diagnosis (73%), family separation (67%), and caring for other children simultaneous during the trial period (60%).

In addition, patients averaged 12 follow-up visits, and the most common secondary challenges cited in the survey included time spent at the hospital, emotional and physical stress on the patient, fear of test results and outcomes, exhaustion, time away from work and school, and travel logistics.

Other stressors include language barriers and not being in children’s hospital, Ms. Price said.

Ms. Price proposed patient-focused solutions such as addressing cultural challenges, connecting families to local resources, and providing clinical follow-up locally to reduce the burden of travel to the trial site.

WASHINGTON– Gene therapy for the treatment of rare diseases continues to develop and new products are entering the pipeline; however, more work is needed to make the gene therapy experience easier on patients and their families, according to members of a panel at the NORD Rare Diseases & Orphan Product Breakthrough Summit, held by the National Organization for Rare Disorders.

Companies developing gene therapy cite their main challenges as identifying patients, developing clinical trials, coordinating treatment and supporting families, managing reimbursement, and manufacturing the treatment, said Mark Rothera, president and CEO of Orchard Therapeutics, developer of ex vivo autologous hematopoietic stem cell gene therapy.

For families of patients with rare diseases who are undergoing gene therapy, challenges include struggles such as language barriers, lack of wifi, and separation from other family members for extended periods, according to Amy Price, mother of a gene therapy recipient, as well as principal consultant to Rarallel and an advocate for metachromatic leukodystrophy.

Ms. Price cited a survey she conducted of families with children who underwent gene therapy. She collected data from 16 families about their initial visit as part of a gene therapy trial; the trials included 14 families in Milan; 1 in Bethesda, Md.; and 1 in Paris. The average age of the patients at the start of the trial was 3 years, with a range of 8 months to 11 years. The trials were conducted between 1990 and 2018.

Families participating in the trials spent an average of 5.5 months in the city where the trial was conducted, and an average of 48 days in an isolation ward with their child at the start of the study.

The five biggest challenges were financial well-being (cited by 60% of survey respondents), social isolation/being away from support system (60%), fear of the unknown/long-term treatment diagnosis (73%), family separation (67%), and caring for other children simultaneous during the trial period (60%).

In addition, patients averaged 12 follow-up visits, and the most common secondary challenges cited in the survey included time spent at the hospital, emotional and physical stress on the patient, fear of test results and outcomes, exhaustion, time away from work and school, and travel logistics.

Other stressors include language barriers and not being in children’s hospital, Ms. Price said.

Ms. Price proposed patient-focused solutions such as addressing cultural challenges, connecting families to local resources, and providing clinical follow-up locally to reduce the burden of travel to the trial site.

WASHINGTON– Gene therapy for the treatment of rare diseases continues to develop and new products are entering the pipeline; however, more work is needed to make the gene therapy experience easier on patients and their families, according to members of a panel at the NORD Rare Diseases & Orphan Product Breakthrough Summit, held by the National Organization for Rare Disorders.

Companies developing gene therapy cite their main challenges as identifying patients, developing clinical trials, coordinating treatment and supporting families, managing reimbursement, and manufacturing the treatment, said Mark Rothera, president and CEO of Orchard Therapeutics, developer of ex vivo autologous hematopoietic stem cell gene therapy.

For families of patients with rare diseases who are undergoing gene therapy, challenges include struggles such as language barriers, lack of wifi, and separation from other family members for extended periods, according to Amy Price, mother of a gene therapy recipient, as well as principal consultant to Rarallel and an advocate for metachromatic leukodystrophy.

Ms. Price cited a survey she conducted of families with children who underwent gene therapy. She collected data from 16 families about their initial visit as part of a gene therapy trial; the trials included 14 families in Milan; 1 in Bethesda, Md.; and 1 in Paris. The average age of the patients at the start of the trial was 3 years, with a range of 8 months to 11 years. The trials were conducted between 1990 and 2018.

Families participating in the trials spent an average of 5.5 months in the city where the trial was conducted, and an average of 48 days in an isolation ward with their child at the start of the study.

The five biggest challenges were financial well-being (cited by 60% of survey respondents), social isolation/being away from support system (60%), fear of the unknown/long-term treatment diagnosis (73%), family separation (67%), and caring for other children simultaneous during the trial period (60%).

In addition, patients averaged 12 follow-up visits, and the most common secondary challenges cited in the survey included time spent at the hospital, emotional and physical stress on the patient, fear of test results and outcomes, exhaustion, time away from work and school, and travel logistics.

Other stressors include language barriers and not being in children’s hospital, Ms. Price said.

Ms. Price proposed patient-focused solutions such as addressing cultural challenges, connecting families to local resources, and providing clinical follow-up locally to reduce the burden of travel to the trial site.

Mint is the most popular flavor among school students who use Juul e-cigarettes, according to data from the 2019 Monitoring the Future study.

Almost half (47.1%) of the 12th graders who had used Juul e-cigarettes in the past 30 days reported that mint was the flavor they most often used, compared with 23.8% for mango and 8.6% for fruit, which is a combination of flavors, Adam M. Leventhal, PhD, of the University of Southern California, Los Angeles, and associates wrote in JAMA.

Mint was also the flavor most often used by 10th graders (43.5%), with mango again second at 27.3%, and fruit third at 10.8%. Eighth-grade students switched mango (33.5%) and mint (29.2%) but had fruit third again at 16.0%, the investigators reported, based on data for 1,739 respondents to the Monitoring the Future survey who had used a vaping product within the past 30 days.

Juul has suspended sales of four – mango, fruit, creme, and cucumber – of its original eight flavors, Dr. Leventhal and associates noted, and e-cigarette flavors other than tobacco, menthol, and mint have been prohibited by some local municipalities.

“The current findings raise uncertainty whether regulations or sales suspensions that exempt mint flavors are optimal strategies for reducing youth e-cigarette use,” they wrote.

As this article was being written, the Wall Street Journal had just reported that the Food and Drug Administration will ban mint and all other e-cigarette flavors except tobacco and menthol.

[email protected]

SOURCE: Leventhal AM et al. JAMA. 2019 Nov 5. doi: 10.1001/jama.2019.17968.

Mint is the most popular flavor among school students who use Juul e-cigarettes, according to data from the 2019 Monitoring the Future study.

Almost half (47.1%) of the 12th graders who had used Juul e-cigarettes in the past 30 days reported that mint was the flavor they most often used, compared with 23.8% for mango and 8.6% for fruit, which is a combination of flavors, Adam M. Leventhal, PhD, of the University of Southern California, Los Angeles, and associates wrote in JAMA.

Mint was also the flavor most often used by 10th graders (43.5%), with mango again second at 27.3%, and fruit third at 10.8%. Eighth-grade students switched mango (33.5%) and mint (29.2%) but had fruit third again at 16.0%, the investigators reported, based on data for 1,739 respondents to the Monitoring the Future survey who had used a vaping product within the past 30 days.

Juul has suspended sales of four – mango, fruit, creme, and cucumber – of its original eight flavors, Dr. Leventhal and associates noted, and e-cigarette flavors other than tobacco, menthol, and mint have been prohibited by some local municipalities.

“The current findings raise uncertainty whether regulations or sales suspensions that exempt mint flavors are optimal strategies for reducing youth e-cigarette use,” they wrote.

As this article was being written, the Wall Street Journal had just reported that the Food and Drug Administration will ban mint and all other e-cigarette flavors except tobacco and menthol.

[email protected]

SOURCE: Leventhal AM et al. JAMA. 2019 Nov 5. doi: 10.1001/jama.2019.17968.

Mint is the most popular flavor among school students who use Juul e-cigarettes, according to data from the 2019 Monitoring the Future study.

Almost half (47.1%) of the 12th graders who had used Juul e-cigarettes in the past 30 days reported that mint was the flavor they most often used, compared with 23.8% for mango and 8.6% for fruit, which is a combination of flavors, Adam M. Leventhal, PhD, of the University of Southern California, Los Angeles, and associates wrote in JAMA.

Mint was also the flavor most often used by 10th graders (43.5%), with mango again second at 27.3%, and fruit third at 10.8%. Eighth-grade students switched mango (33.5%) and mint (29.2%) but had fruit third again at 16.0%, the investigators reported, based on data for 1,739 respondents to the Monitoring the Future survey who had used a vaping product within the past 30 days.

Juul has suspended sales of four – mango, fruit, creme, and cucumber – of its original eight flavors, Dr. Leventhal and associates noted, and e-cigarette flavors other than tobacco, menthol, and mint have been prohibited by some local municipalities.

“The current findings raise uncertainty whether regulations or sales suspensions that exempt mint flavors are optimal strategies for reducing youth e-cigarette use,” they wrote.

As this article was being written, the Wall Street Journal had just reported that the Food and Drug Administration will ban mint and all other e-cigarette flavors except tobacco and menthol.

[email protected]

SOURCE: Leventhal AM et al. JAMA. 2019 Nov 5. doi: 10.1001/jama.2019.17968.

Antifungal prophylaxis with caspofungin led to a lower incidence of invasive fungal disease, compared with fluconazole, in children and young adults with acute myeloid leukemia (AML), according to new study findings.

National Institutes of Health/Wikimedia Commons/Public Domain

The results suggest caspofungin may be an appropriate prophylactic strategy to prevent invasive fungal disease in younger patients with newly diagnosed AML, reported Brian T. Fisher, DO, of the University of Pennsylvania, Philadelphia, and colleagues. The study was published in JAMA.

The randomized, open-label study included 517 children, adolescents, and young adults with de novo, relapsed, or secondary AML. Study patients received treatment in 115 centers throughout United States and Canada. The median age of patients in the study was 9 years (range, 0-26 years); 56% were male and approximately 69% were white.

Study subjects were randomly assigned to receive antifungal prophylaxis with 70 mg/m² (maximum dose 70 mg/day) of intravenous caspofungin on day 1, followed by 50 mg/m² per day (maximum dose 50 mg/day) thereafter, or age-dosed intravenous or oral fluconazole.

Prophylactic therapy was initiated 24-72 hours after the completion of each chemotherapy cycle, and was maintained until the end of the neutropenic period following each cycle.

At 5-month follow-up, the cumulative incidence rate of probable or proven invasive fungal disease was 3.1% (95% confidence interval, 1.3%-7.0%) in the caspofungin arm, compared with 7.2% (95% CI, 4.4%-11.8%) in the fluconazole arm (overall P = .03).

In addition, the 5-month cumulative incidence rate of probable or proven invasive aspergillosis infection was 0.5% (95%CI, 0.1%-3.5%) in patients who received caspofungin, compared with 3.1% (95% CI, 1.4%-6.9%) in patients who received fluconazole (overall P = .046).

“No statistically significant differences in empirical antifungal therapy or 2-year overall survival were observed,” they reported.

With respect to safety, the most frequently reported adverse events were hypokalemia (22 events in the caspofungin arm vs. 13 in the fluconazole arm), respiratory failure (6 events in the caspofungin arm vs. 9 in the fluconazole arm), and elevated alanine transaminase (4 events in the caspofungin arm vs. 8 in the fluconazole arm).

The researchers acknowledged a key limitation of the study was the short duration of follow-up. As a result, the precision of some comparative measures may have been reduced.

The National Cancer Institute funded the study. The authors reported financial affiliations with Astellas, Celgene, Leadiant Biosciences, Merck, Nabriva Therapeutics, Novartis, Pfizer, Shire, and T2 Biosystems.

SOURCE: Fisher BT et al. JAMA. 2019;322(17):1673-81.

Antifungal prophylaxis with caspofungin led to a lower incidence of invasive fungal disease, compared with fluconazole, in children and young adults with acute myeloid leukemia (AML), according to new study findings.

National Institutes of Health/Wikimedia Commons/Public Domain

The results suggest caspofungin may be an appropriate prophylactic strategy to prevent invasive fungal disease in younger patients with newly diagnosed AML, reported Brian T. Fisher, DO, of the University of Pennsylvania, Philadelphia, and colleagues. The study was published in JAMA.

The randomized, open-label study included 517 children, adolescents, and young adults with de novo, relapsed, or secondary AML. Study patients received treatment in 115 centers throughout United States and Canada. The median age of patients in the study was 9 years (range, 0-26 years); 56% were male and approximately 69% were white.

Study subjects were randomly assigned to receive antifungal prophylaxis with 70 mg/m² (maximum dose 70 mg/day) of intravenous caspofungin on day 1, followed by 50 mg/m² per day (maximum dose 50 mg/day) thereafter, or age-dosed intravenous or oral fluconazole.

Prophylactic therapy was initiated 24-72 hours after the completion of each chemotherapy cycle, and was maintained until the end of the neutropenic period following each cycle.

At 5-month follow-up, the cumulative incidence rate of probable or proven invasive fungal disease was 3.1% (95% confidence interval, 1.3%-7.0%) in the caspofungin arm, compared with 7.2% (95% CI, 4.4%-11.8%) in the fluconazole arm (overall P = .03).

In addition, the 5-month cumulative incidence rate of probable or proven invasive aspergillosis infection was 0.5% (95%CI, 0.1%-3.5%) in patients who received caspofungin, compared with 3.1% (95% CI, 1.4%-6.9%) in patients who received fluconazole (overall P = .046).

“No statistically significant differences in empirical antifungal therapy or 2-year overall survival were observed,” they reported.

With respect to safety, the most frequently reported adverse events were hypokalemia (22 events in the caspofungin arm vs. 13 in the fluconazole arm), respiratory failure (6 events in the caspofungin arm vs. 9 in the fluconazole arm), and elevated alanine transaminase (4 events in the caspofungin arm vs. 8 in the fluconazole arm).

The researchers acknowledged a key limitation of the study was the short duration of follow-up. As a result, the precision of some comparative measures may have been reduced.

The National Cancer Institute funded the study. The authors reported financial affiliations with Astellas, Celgene, Leadiant Biosciences, Merck, Nabriva Therapeutics, Novartis, Pfizer, Shire, and T2 Biosystems.

SOURCE: Fisher BT et al. JAMA. 2019;322(17):1673-81.

Antifungal prophylaxis with caspofungin led to a lower incidence of invasive fungal disease, compared with fluconazole, in children and young adults with acute myeloid leukemia (AML), according to new study findings.

National Institutes of Health/Wikimedia Commons/Public Domain

The results suggest caspofungin may be an appropriate prophylactic strategy to prevent invasive fungal disease in younger patients with newly diagnosed AML, reported Brian T. Fisher, DO, of the University of Pennsylvania, Philadelphia, and colleagues. The study was published in JAMA.

The randomized, open-label study included 517 children, adolescents, and young adults with de novo, relapsed, or secondary AML. Study patients received treatment in 115 centers throughout United States and Canada. The median age of patients in the study was 9 years (range, 0-26 years); 56% were male and approximately 69% were white.

Study subjects were randomly assigned to receive antifungal prophylaxis with 70 mg/m² (maximum dose 70 mg/day) of intravenous caspofungin on day 1, followed by 50 mg/m² per day (maximum dose 50 mg/day) thereafter, or age-dosed intravenous or oral fluconazole.

Prophylactic therapy was initiated 24-72 hours after the completion of each chemotherapy cycle, and was maintained until the end of the neutropenic period following each cycle.

At 5-month follow-up, the cumulative incidence rate of probable or proven invasive fungal disease was 3.1% (95% confidence interval, 1.3%-7.0%) in the caspofungin arm, compared with 7.2% (95% CI, 4.4%-11.8%) in the fluconazole arm (overall P = .03).

In addition, the 5-month cumulative incidence rate of probable or proven invasive aspergillosis infection was 0.5% (95%CI, 0.1%-3.5%) in patients who received caspofungin, compared with 3.1% (95% CI, 1.4%-6.9%) in patients who received fluconazole (overall P = .046).

“No statistically significant differences in empirical antifungal therapy or 2-year overall survival were observed,” they reported.

With respect to safety, the most frequently reported adverse events were hypokalemia (22 events in the caspofungin arm vs. 13 in the fluconazole arm), respiratory failure (6 events in the caspofungin arm vs. 9 in the fluconazole arm), and elevated alanine transaminase (4 events in the caspofungin arm vs. 8 in the fluconazole arm).

The researchers acknowledged a key limitation of the study was the short duration of follow-up. As a result, the precision of some comparative measures may have been reduced.

The National Cancer Institute funded the study. The authors reported financial affiliations with Astellas, Celgene, Leadiant Biosciences, Merck, Nabriva Therapeutics, Novartis, Pfizer, Shire, and T2 Biosystems.

SOURCE: Fisher BT et al. JAMA. 2019;322(17):1673-81.

Case Report

A 7-year-old Chinese boy presented with multiple painful oral and tongue ulcers of 2 weeks’ duration as well as acute onset of moderate to high fever (highest temperature, 39.3°C) for 5 days. The fever was reported to have run a relapsing course, accompanied by rigors but without convulsions or cognitive changes. At times, the patient had nasal congestion, nasal discharge, and cough. He also had a transient eruption on the back and hands as well as an indurated red nodule on the left forearm.

Before the patient was hospitalized, antibiotic therapy was administered by other physicians, but the condition of fever and oral ulcers did not improve. After the patient was hospitalized, new tender nodules emerged on the scalp, buttocks, and lower extremities. New ulcers also appeared on the palate.

History
Two months earlier, the patient had presented with a painful perioral skin ulcer that resolved after being treated as contagious eczema. Another dermatologist previously had considered a diagnosis of hand-foot-and-mouth disease.

The patient was born by normal spontaneous vaginal delivery, without abnormality. He was breastfed; feeding, growth, and the developmental history showed no abnormality. He was the family’s eldest child, with a healthy brother and sister. There was no history of familial illness. He received bacillus Calmette-Guérin and poliomyelitis vaccines after birth; the rest of the vaccine history was unclear. There was no history of immunologic abnormality.

Physical Examination
A 1.5×1.5-cm, warm, red nodule with a central black crust was noted on the left forearm (Figure 1A). Several similar lesions were noted on the buttocks, scalp, and lower extremities. Multiple ulcers, as large as 1 cm, were present on the tongue, palate, and left angle of the mouth (Figure 1B). The pharynx was congested, and the tonsils were mildly enlarged. Multiple enlarged, movable, nontender lymph nodes could be palpated in the cervical basins, axillae, and groin. No purpura or ecchymosis was detected.

Laboratory Results
Laboratory testing revealed a normal total white blood cell count (4.26×10⁹/L [reference range, 4.0–12.0×10⁹/L]), with normal neutrophils (1.36×10⁹/L [reference range, 1.32–7.90×10⁹/L]), lymphocytes (2.77×10⁹/L [reference range, 1.20–6.00×10⁹/L]), and monocytes (0.13×10⁹/L [reference range, 0.08–0.80×10⁹/L]); a mildly decreased hemoglobin level (115 g/L [reference range, 120–160 g/L]); a normal platelet count (102×10⁹/L [reference range, 100–380×10⁹/L]); an elevated lactate dehydrogenase level (614 U/L [reference range, 110–330 U/L]); an elevated α-hydroxybutyrate dehydrogenase level (483 U/L [reference range, 120–270 U/L]); elevated prothrombin time (15.3 s [reference range, 9–14 s]); elevated activated partial thromboplastin time (59.8 s [reference range, 20.6–39.6 s]); and an elevated D-dimer level (1.51 mg/L [reference range, <0.73 mg/L]). In addition, autoantibody testing revealed a positive antinuclear antibody titer of 1:320 and a strong positive anti–Ro-52 level.

The peripheral blood lymphocyte classification demonstrated a prominent elevated percentage of T lymphocytes, with predominantly CD8⁺ cells (CD3, 94.87%; CD8, 71.57%; CD4, 24.98%; CD4:CD8 ratio, 0.35) and a diminished percentage of B lymphocytes and natural killer (NK) cells. Epstein-Barr virus (EBV) antibody testing was positive for anti–viral capsid antigen (VCA) IgG and negative for anti-VCA IgM.

Smears of the ulcer on the tongue demonstrated gram-positive cocci, gram-negative bacilli, and diplococci. Culture of sputum showed methicillin-resistant Staphylococcus aureus. Inspection for acid-fast bacilli in sputum yielded negative results 3 times. A purified protein derivative skin test for Mycobacterium tuberculosis infection was negative.

Imaging and Other Studies
Computed tomography of the chest and abdomen demonstrated 2 nodular opacities on the lower right lung; spotted opacities on the upper right lung; floccular opacities on the rest area of the lung; mild pleural effusion; enlargement of lymph nodes on the mediastinum, the bilateral hilum of the lung, and mesentery; and hepatosplenomegaly. Electrocardiography showed sinus tachycardia. Nasal cavity endoscopy showed sinusitis. Fundus examination showed vasculopathy of the left retina. A colonoscopy showed normal mucosa.

Histopathology
Biopsy of the nodule on the left arm showed dense, superficial to deep perivascular, periadnexal, perineural, and panniculitislike lymphoid infiltrates, as well as a sparse interstitial infiltrate with irregular and pleomorphic medium to large nuclei. Lymphoid cells showed mild epidermotropism, with tagging to the basal layer. Some vessel walls were infiltrated by similar cells (Figure 2). Infiltrative atypical lymphoid cells expressed CD3 and CD7 and were mostly CD8⁺, with a few CD4⁺ cells and most cells negative for CD5, CD20, CD30, CD56, and anaplastic lymphoma kinase. Cytotoxic markers granzyme B and T-cell intracellular antigen protein 1 were scattered positive. Immunostaining for Ki-67 protein highlighted an increased proliferative rate of 80% in malignant cells. In situ hybridization for EBV-encoded RNA (EBER) demonstrated EBV-positive atypical lymphoid cells (Figure 3). Analysis for T-cell receptor (TCR) γ gene rearrangement revealed a monoclonal pattern. Bone marrow aspirate showed proliferation of the 3 cell lines. The percentage of T lymphocytes was increased (20% of all nucleated cells). No hemophagocytic activity was found.

The patient’s parents refused to accept chemotherapy for him. Instead, they chose herbal therapy only; 5 months later, they reported that all of his symptoms had resolved; however, the disease suddenly relapsed after another 7 months, with multiple skin nodules and fever. The patient died, even with chemotherapy in another hospital.

Comment

Prevalence and Presentation
Epstein-Barr virus is a ubiquitous γ-herpesvirus with tropism for B cells, affecting more than 90% of the adult population worldwide. In addition to infecting B cells, EBV is capable of infecting T and NK cells, leading to various EBV-related lymphoproliferative disorders (LPDs). The frequency and clinical presentation of infection varies based on the type of EBV-infected cells and the state of host immunity.^1-3

Primary infection usually is asymptomatic and occurs early in life; when symptomatic, the disease usually presents as infectious mononucleosis (IM), characterized by polyclonal expansion of infected B cells and subsequent cytotoxic T-cell response. A diagnosis of EBV infection can be made by testing for specific IgM and IgG antibodies against VCA, early antigens, and EBV nuclear antigen proteins.^3,4

Associated LPDs
Although most symptoms associated with IM resolve within weeks or months, persistent or recurrent IM-like symptoms or even lasting disease occasionally occur, particularly in children and young adults. This complication is known as chronic active EBV infection (CAEBV), frequently associated with EBV-infected T-cell or NK-cell proliferation, especially in East Asian populations.^3,5

Epstein-Barr virus–positive T-cell and NK-cell LPDs of childhood include CAEBV infection of T-cell and NK-cell types and systemic EBV-positive T-cell lymphoma of childhood. The former includes hydroa vacciniforme–like LPD and severe mosquito bite allergy.³

Systemic EBV-Positive T-cell Lymphoma of Childhood
This entity occurs not only in children but also in adolescents and young adults. A fulminant illness characterized by clonal proliferation of EBV-infected cytotoxic T cells, it can develop shortly after primary EBV infection or is linked to CAEBV infection. The disorder is rare and has a racial predilection for Asian (ie, Japanese, Chinese, Korean) populations and indigenous populations of Mexico and Central and South America.^6-8

Complications
Systemic EBV-positive T-cell lymphoma of childhood is often complicated by hemophagocytic syndrome, coagulopathy, sepsis, and multiorgan failure. Other signs and symptoms include high fever, rash, jaundice, diarrhea, pancytopenia, and hepatosplenomegaly. The liver, spleen, lymph nodes, and bone marrow are commonly involved, and the disease can involve skin, the heart, and the lungs.^9,10

Diagnosis
When systemic EBV-positive T-cell lymphoma occurs shortly after IM, serology shows low or absent anti-VCA IgM and positive anti-VCA IgG. Infiltrating T cells usually are small and lack cytologic atypia; however, cases with pleomorphic, medium to large lymphoid cells, irregular nuclei, and frequent mitoses have been described. Hemophagocytosis can be seen in the liver, spleen, and bone marrow.^3,11

The most typical phenotype of systemic EBV-positive T-cell lymphoma is CD2⁺CD3⁺CD8⁺CD20⁻CD56⁻, with expression of the cytotoxic granules known as T-cell intracellular antigen 1 and granzyme B. Rare cases of CD4⁺ and mixed CD4⁺/CD8⁺ phenotypes have been described, usually in the setting of CAEBV infection.^3,12 Neoplastic cells have monoclonally rearranged TCR-γ genes and consistent EBER positivity with in situ hybridization.¹³ A final diagnosis is based on a comprehensive analysis of clinical, morphological, immunohistochemical, and molecular biological aspects.

Clinical Course and Prognosis
Most patients with systemic EBV-positive T-cell lymphoma have an aggressive clinical course with high mortality. In a few cases, patients were reported to respond to a regimen of etoposide and dexamethasone, followed by allogeneic hematopoietic stem cell transplantation.³

In recognition of the aggressive clinical behavior and desire to clearly distinguish systemic EBV-positive T-cell lymphoma from CAEBV infection, the older term systemic EBV-positive T-cell LPD of childhood, which had been introduced in 2008 to the World Health Organization classification, was changed to systemic EBV-positive T-cell lymphoma of childhood in the revised 2016 World Health Organization classification.^6,12 However, Kim et al¹⁴ reported a case with excellent response to corticosteroid administration, suggesting that systemic EBV-positive T-cell lymphoma of childhood may be more heterogeneous in terms of prognosis.

Our patient presented with acute IM-like symptoms, including high fever, tonsillar enlargement, lymphadenopathy, and hepatosplenomegaly, as well as uncommon oral ulcers and skin lesions, including indurated nodules. Histopathologic changes in the skin nodule, proliferation in bone marrow, immunohistochemical phenotype, and positivity of EBER and TCR-γ monoclonal rearrangement were all consistent with systemic EBV-positive T-cell lymphoma of childhood. The patient was positive for VCA IgG and negative for VCA IgM, compatible with systemic EBV-positive T-cell lymphoma of childhood occurring shortly after IM. Neither pancytopenia, hemophagocytic syndrome, nor multiorgan failure occurred during the course.

Differential Diagnosis
It is important to distinguish IM from systemic EBV-positive T-cell lymphoma of childhood and CAEBV infection. Detection of anti–VCA IgM in the early stage, its disappearance during the clinical course, and appearance of anti-EBV–determined nuclear antigen is useful to distinguish IM from the neoplasms, as systemic EBV-positive T-cell lymphoma of childhood is negative for anti-EBV–determined nuclear antigen. Carefully following the clinical course also is important.^3,15

Epstein-Barr virus–associated hemophagocytic lymphohistiocytosis can occur in association with systemic EBV-positive T-cell lymphoma of childhood and might represent a continuum of disease rather than distinct entities.¹⁴ The most useful marker for differentiating EBV-associated hemophagocytic lymphohistiocytosis and systemic EBV-positive T-cell lymphoma of childhood is an abnormal karyotype rather than molecular clonality.¹⁶

Outcome
Mortality risk in EBV-associated T-cell and NK-cell LPD is not primarily dependent on whether the lesion has progressed to lymphoma but instead is related to associated complications.¹⁷

Conclusion

Although systemic EBV-positive T-cell lymphoma of childhood is a rare disorder and has race predilection, dermatologists should be aware due to the aggressive clinical source and poor prognosis. Histopathology and in situ hybridization for EBER and TCR gene rearrangements are critical for final diagnosis. Although rare cases can show temporary resolution, the final outcome of this disease is not optimistic.

Case Report

A 7-year-old Chinese boy presented with multiple painful oral and tongue ulcers of 2 weeks’ duration as well as acute onset of moderate to high fever (highest temperature, 39.3°C) for 5 days. The fever was reported to have run a relapsing course, accompanied by rigors but without convulsions or cognitive changes. At times, the patient had nasal congestion, nasal discharge, and cough. He also had a transient eruption on the back and hands as well as an indurated red nodule on the left forearm.

Before the patient was hospitalized, antibiotic therapy was administered by other physicians, but the condition of fever and oral ulcers did not improve. After the patient was hospitalized, new tender nodules emerged on the scalp, buttocks, and lower extremities. New ulcers also appeared on the palate.

History
Two months earlier, the patient had presented with a painful perioral skin ulcer that resolved after being treated as contagious eczema. Another dermatologist previously had considered a diagnosis of hand-foot-and-mouth disease.

The patient was born by normal spontaneous vaginal delivery, without abnormality. He was breastfed; feeding, growth, and the developmental history showed no abnormality. He was the family’s eldest child, with a healthy brother and sister. There was no history of familial illness. He received bacillus Calmette-Guérin and poliomyelitis vaccines after birth; the rest of the vaccine history was unclear. There was no history of immunologic abnormality.

Physical Examination
A 1.5×1.5-cm, warm, red nodule with a central black crust was noted on the left forearm (Figure 1A). Several similar lesions were noted on the buttocks, scalp, and lower extremities. Multiple ulcers, as large as 1 cm, were present on the tongue, palate, and left angle of the mouth (Figure 1B). The pharynx was congested, and the tonsils were mildly enlarged. Multiple enlarged, movable, nontender lymph nodes could be palpated in the cervical basins, axillae, and groin. No purpura or ecchymosis was detected.

Laboratory Results
Laboratory testing revealed a normal total white blood cell count (4.26×10⁹/L [reference range, 4.0–12.0×10⁹/L]), with normal neutrophils (1.36×10⁹/L [reference range, 1.32–7.90×10⁹/L]), lymphocytes (2.77×10⁹/L [reference range, 1.20–6.00×10⁹/L]), and monocytes (0.13×10⁹/L [reference range, 0.08–0.80×10⁹/L]); a mildly decreased hemoglobin level (115 g/L [reference range, 120–160 g/L]); a normal platelet count (102×10⁹/L [reference range, 100–380×10⁹/L]); an elevated lactate dehydrogenase level (614 U/L [reference range, 110–330 U/L]); an elevated α-hydroxybutyrate dehydrogenase level (483 U/L [reference range, 120–270 U/L]); elevated prothrombin time (15.3 s [reference range, 9–14 s]); elevated activated partial thromboplastin time (59.8 s [reference range, 20.6–39.6 s]); and an elevated D-dimer level (1.51 mg/L [reference range, <0.73 mg/L]). In addition, autoantibody testing revealed a positive antinuclear antibody titer of 1:320 and a strong positive anti–Ro-52 level.

The peripheral blood lymphocyte classification demonstrated a prominent elevated percentage of T lymphocytes, with predominantly CD8⁺ cells (CD3, 94.87%; CD8, 71.57%; CD4, 24.98%; CD4:CD8 ratio, 0.35) and a diminished percentage of B lymphocytes and natural killer (NK) cells. Epstein-Barr virus (EBV) antibody testing was positive for anti–viral capsid antigen (VCA) IgG and negative for anti-VCA IgM.

Smears of the ulcer on the tongue demonstrated gram-positive cocci, gram-negative bacilli, and diplococci. Culture of sputum showed methicillin-resistant Staphylococcus aureus. Inspection for acid-fast bacilli in sputum yielded negative results 3 times. A purified protein derivative skin test for Mycobacterium tuberculosis infection was negative.

Imaging and Other Studies
Computed tomography of the chest and abdomen demonstrated 2 nodular opacities on the lower right lung; spotted opacities on the upper right lung; floccular opacities on the rest area of the lung; mild pleural effusion; enlargement of lymph nodes on the mediastinum, the bilateral hilum of the lung, and mesentery; and hepatosplenomegaly. Electrocardiography showed sinus tachycardia. Nasal cavity endoscopy showed sinusitis. Fundus examination showed vasculopathy of the left retina. A colonoscopy showed normal mucosa.

Histopathology
Biopsy of the nodule on the left arm showed dense, superficial to deep perivascular, periadnexal, perineural, and panniculitislike lymphoid infiltrates, as well as a sparse interstitial infiltrate with irregular and pleomorphic medium to large nuclei. Lymphoid cells showed mild epidermotropism, with tagging to the basal layer. Some vessel walls were infiltrated by similar cells (Figure 2). Infiltrative atypical lymphoid cells expressed CD3 and CD7 and were mostly CD8⁺, with a few CD4⁺ cells and most cells negative for CD5, CD20, CD30, CD56, and anaplastic lymphoma kinase. Cytotoxic markers granzyme B and T-cell intracellular antigen protein 1 were scattered positive. Immunostaining for Ki-67 protein highlighted an increased proliferative rate of 80% in malignant cells. In situ hybridization for EBV-encoded RNA (EBER) demonstrated EBV-positive atypical lymphoid cells (Figure 3). Analysis for T-cell receptor (TCR) γ gene rearrangement revealed a monoclonal pattern. Bone marrow aspirate showed proliferation of the 3 cell lines. The percentage of T lymphocytes was increased (20% of all nucleated cells). No hemophagocytic activity was found.

The patient’s parents refused to accept chemotherapy for him. Instead, they chose herbal therapy only; 5 months later, they reported that all of his symptoms had resolved; however, the disease suddenly relapsed after another 7 months, with multiple skin nodules and fever. The patient died, even with chemotherapy in another hospital.

Comment

Prevalence and Presentation
Epstein-Barr virus is a ubiquitous γ-herpesvirus with tropism for B cells, affecting more than 90% of the adult population worldwide. In addition to infecting B cells, EBV is capable of infecting T and NK cells, leading to various EBV-related lymphoproliferative disorders (LPDs). The frequency and clinical presentation of infection varies based on the type of EBV-infected cells and the state of host immunity.^1-3

Primary infection usually is asymptomatic and occurs early in life; when symptomatic, the disease usually presents as infectious mononucleosis (IM), characterized by polyclonal expansion of infected B cells and subsequent cytotoxic T-cell response. A diagnosis of EBV infection can be made by testing for specific IgM and IgG antibodies against VCA, early antigens, and EBV nuclear antigen proteins.^3,4

Associated LPDs
Although most symptoms associated with IM resolve within weeks or months, persistent or recurrent IM-like symptoms or even lasting disease occasionally occur, particularly in children and young adults. This complication is known as chronic active EBV infection (CAEBV), frequently associated with EBV-infected T-cell or NK-cell proliferation, especially in East Asian populations.^3,5

Epstein-Barr virus–positive T-cell and NK-cell LPDs of childhood include CAEBV infection of T-cell and NK-cell types and systemic EBV-positive T-cell lymphoma of childhood. The former includes hydroa vacciniforme–like LPD and severe mosquito bite allergy.³

Systemic EBV-Positive T-cell Lymphoma of Childhood
This entity occurs not only in children but also in adolescents and young adults. A fulminant illness characterized by clonal proliferation of EBV-infected cytotoxic T cells, it can develop shortly after primary EBV infection or is linked to CAEBV infection. The disorder is rare and has a racial predilection for Asian (ie, Japanese, Chinese, Korean) populations and indigenous populations of Mexico and Central and South America.^6-8

Complications
Systemic EBV-positive T-cell lymphoma of childhood is often complicated by hemophagocytic syndrome, coagulopathy, sepsis, and multiorgan failure. Other signs and symptoms include high fever, rash, jaundice, diarrhea, pancytopenia, and hepatosplenomegaly. The liver, spleen, lymph nodes, and bone marrow are commonly involved, and the disease can involve skin, the heart, and the lungs.^9,10

Diagnosis
When systemic EBV-positive T-cell lymphoma occurs shortly after IM, serology shows low or absent anti-VCA IgM and positive anti-VCA IgG. Infiltrating T cells usually are small and lack cytologic atypia; however, cases with pleomorphic, medium to large lymphoid cells, irregular nuclei, and frequent mitoses have been described. Hemophagocytosis can be seen in the liver, spleen, and bone marrow.^3,11

The most typical phenotype of systemic EBV-positive T-cell lymphoma is CD2⁺CD3⁺CD8⁺CD20⁻CD56⁻, with expression of the cytotoxic granules known as T-cell intracellular antigen 1 and granzyme B. Rare cases of CD4⁺ and mixed CD4⁺/CD8⁺ phenotypes have been described, usually in the setting of CAEBV infection.^3,12 Neoplastic cells have monoclonally rearranged TCR-γ genes and consistent EBER positivity with in situ hybridization.¹³ A final diagnosis is based on a comprehensive analysis of clinical, morphological, immunohistochemical, and molecular biological aspects.

Clinical Course and Prognosis
Most patients with systemic EBV-positive T-cell lymphoma have an aggressive clinical course with high mortality. In a few cases, patients were reported to respond to a regimen of etoposide and dexamethasone, followed by allogeneic hematopoietic stem cell transplantation.³

In recognition of the aggressive clinical behavior and desire to clearly distinguish systemic EBV-positive T-cell lymphoma from CAEBV infection, the older term systemic EBV-positive T-cell LPD of childhood, which had been introduced in 2008 to the World Health Organization classification, was changed to systemic EBV-positive T-cell lymphoma of childhood in the revised 2016 World Health Organization classification.^6,12 However, Kim et al¹⁴ reported a case with excellent response to corticosteroid administration, suggesting that systemic EBV-positive T-cell lymphoma of childhood may be more heterogeneous in terms of prognosis.

Our patient presented with acute IM-like symptoms, including high fever, tonsillar enlargement, lymphadenopathy, and hepatosplenomegaly, as well as uncommon oral ulcers and skin lesions, including indurated nodules. Histopathologic changes in the skin nodule, proliferation in bone marrow, immunohistochemical phenotype, and positivity of EBER and TCR-γ monoclonal rearrangement were all consistent with systemic EBV-positive T-cell lymphoma of childhood. The patient was positive for VCA IgG and negative for VCA IgM, compatible with systemic EBV-positive T-cell lymphoma of childhood occurring shortly after IM. Neither pancytopenia, hemophagocytic syndrome, nor multiorgan failure occurred during the course.

Differential Diagnosis
It is important to distinguish IM from systemic EBV-positive T-cell lymphoma of childhood and CAEBV infection. Detection of anti–VCA IgM in the early stage, its disappearance during the clinical course, and appearance of anti-EBV–determined nuclear antigen is useful to distinguish IM from the neoplasms, as systemic EBV-positive T-cell lymphoma of childhood is negative for anti-EBV–determined nuclear antigen. Carefully following the clinical course also is important.^3,15

Epstein-Barr virus–associated hemophagocytic lymphohistiocytosis can occur in association with systemic EBV-positive T-cell lymphoma of childhood and might represent a continuum of disease rather than distinct entities.¹⁴ The most useful marker for differentiating EBV-associated hemophagocytic lymphohistiocytosis and systemic EBV-positive T-cell lymphoma of childhood is an abnormal karyotype rather than molecular clonality.¹⁶

Outcome
Mortality risk in EBV-associated T-cell and NK-cell LPD is not primarily dependent on whether the lesion has progressed to lymphoma but instead is related to associated complications.¹⁷

Conclusion

Although systemic EBV-positive T-cell lymphoma of childhood is a rare disorder and has race predilection, dermatologists should be aware due to the aggressive clinical source and poor prognosis. Histopathology and in situ hybridization for EBER and TCR gene rearrangements are critical for final diagnosis. Although rare cases can show temporary resolution, the final outcome of this disease is not optimistic.

Case Report

A 7-year-old Chinese boy presented with multiple painful oral and tongue ulcers of 2 weeks’ duration as well as acute onset of moderate to high fever (highest temperature, 39.3°C) for 5 days. The fever was reported to have run a relapsing course, accompanied by rigors but without convulsions or cognitive changes. At times, the patient had nasal congestion, nasal discharge, and cough. He also had a transient eruption on the back and hands as well as an indurated red nodule on the left forearm.

Before the patient was hospitalized, antibiotic therapy was administered by other physicians, but the condition of fever and oral ulcers did not improve. After the patient was hospitalized, new tender nodules emerged on the scalp, buttocks, and lower extremities. New ulcers also appeared on the palate.

History
Two months earlier, the patient had presented with a painful perioral skin ulcer that resolved after being treated as contagious eczema. Another dermatologist previously had considered a diagnosis of hand-foot-and-mouth disease.

The patient was born by normal spontaneous vaginal delivery, without abnormality. He was breastfed; feeding, growth, and the developmental history showed no abnormality. He was the family’s eldest child, with a healthy brother and sister. There was no history of familial illness. He received bacillus Calmette-Guérin and poliomyelitis vaccines after birth; the rest of the vaccine history was unclear. There was no history of immunologic abnormality.

Physical Examination
A 1.5×1.5-cm, warm, red nodule with a central black crust was noted on the left forearm (Figure 1A). Several similar lesions were noted on the buttocks, scalp, and lower extremities. Multiple ulcers, as large as 1 cm, were present on the tongue, palate, and left angle of the mouth (Figure 1B). The pharynx was congested, and the tonsils were mildly enlarged. Multiple enlarged, movable, nontender lymph nodes could be palpated in the cervical basins, axillae, and groin. No purpura or ecchymosis was detected.

Laboratory Results
Laboratory testing revealed a normal total white blood cell count (4.26×10⁹/L [reference range, 4.0–12.0×10⁹/L]), with normal neutrophils (1.36×10⁹/L [reference range, 1.32–7.90×10⁹/L]), lymphocytes (2.77×10⁹/L [reference range, 1.20–6.00×10⁹/L]), and monocytes (0.13×10⁹/L [reference range, 0.08–0.80×10⁹/L]); a mildly decreased hemoglobin level (115 g/L [reference range, 120–160 g/L]); a normal platelet count (102×10⁹/L [reference range, 100–380×10⁹/L]); an elevated lactate dehydrogenase level (614 U/L [reference range, 110–330 U/L]); an elevated α-hydroxybutyrate dehydrogenase level (483 U/L [reference range, 120–270 U/L]); elevated prothrombin time (15.3 s [reference range, 9–14 s]); elevated activated partial thromboplastin time (59.8 s [reference range, 20.6–39.6 s]); and an elevated D-dimer level (1.51 mg/L [reference range, <0.73 mg/L]). In addition, autoantibody testing revealed a positive antinuclear antibody titer of 1:320 and a strong positive anti–Ro-52 level.

The peripheral blood lymphocyte classification demonstrated a prominent elevated percentage of T lymphocytes, with predominantly CD8⁺ cells (CD3, 94.87%; CD8, 71.57%; CD4, 24.98%; CD4:CD8 ratio, 0.35) and a diminished percentage of B lymphocytes and natural killer (NK) cells. Epstein-Barr virus (EBV) antibody testing was positive for anti–viral capsid antigen (VCA) IgG and negative for anti-VCA IgM.

Smears of the ulcer on the tongue demonstrated gram-positive cocci, gram-negative bacilli, and diplococci. Culture of sputum showed methicillin-resistant Staphylococcus aureus. Inspection for acid-fast bacilli in sputum yielded negative results 3 times. A purified protein derivative skin test for Mycobacterium tuberculosis infection was negative.

Imaging and Other Studies
Computed tomography of the chest and abdomen demonstrated 2 nodular opacities on the lower right lung; spotted opacities on the upper right lung; floccular opacities on the rest area of the lung; mild pleural effusion; enlargement of lymph nodes on the mediastinum, the bilateral hilum of the lung, and mesentery; and hepatosplenomegaly. Electrocardiography showed sinus tachycardia. Nasal cavity endoscopy showed sinusitis. Fundus examination showed vasculopathy of the left retina. A colonoscopy showed normal mucosa.

Histopathology
Biopsy of the nodule on the left arm showed dense, superficial to deep perivascular, periadnexal, perineural, and panniculitislike lymphoid infiltrates, as well as a sparse interstitial infiltrate with irregular and pleomorphic medium to large nuclei. Lymphoid cells showed mild epidermotropism, with tagging to the basal layer. Some vessel walls were infiltrated by similar cells (Figure 2). Infiltrative atypical lymphoid cells expressed CD3 and CD7 and were mostly CD8⁺, with a few CD4⁺ cells and most cells negative for CD5, CD20, CD30, CD56, and anaplastic lymphoma kinase. Cytotoxic markers granzyme B and T-cell intracellular antigen protein 1 were scattered positive. Immunostaining for Ki-67 protein highlighted an increased proliferative rate of 80% in malignant cells. In situ hybridization for EBV-encoded RNA (EBER) demonstrated EBV-positive atypical lymphoid cells (Figure 3). Analysis for T-cell receptor (TCR) γ gene rearrangement revealed a monoclonal pattern. Bone marrow aspirate showed proliferation of the 3 cell lines. The percentage of T lymphocytes was increased (20% of all nucleated cells). No hemophagocytic activity was found.

The patient’s parents refused to accept chemotherapy for him. Instead, they chose herbal therapy only; 5 months later, they reported that all of his symptoms had resolved; however, the disease suddenly relapsed after another 7 months, with multiple skin nodules and fever. The patient died, even with chemotherapy in another hospital.

Comment

Prevalence and Presentation
Epstein-Barr virus is a ubiquitous γ-herpesvirus with tropism for B cells, affecting more than 90% of the adult population worldwide. In addition to infecting B cells, EBV is capable of infecting T and NK cells, leading to various EBV-related lymphoproliferative disorders (LPDs). The frequency and clinical presentation of infection varies based on the type of EBV-infected cells and the state of host immunity.^1-3

Primary infection usually is asymptomatic and occurs early in life; when symptomatic, the disease usually presents as infectious mononucleosis (IM), characterized by polyclonal expansion of infected B cells and subsequent cytotoxic T-cell response. A diagnosis of EBV infection can be made by testing for specific IgM and IgG antibodies against VCA, early antigens, and EBV nuclear antigen proteins.^3,4

Associated LPDs
Although most symptoms associated with IM resolve within weeks or months, persistent or recurrent IM-like symptoms or even lasting disease occasionally occur, particularly in children and young adults. This complication is known as chronic active EBV infection (CAEBV), frequently associated with EBV-infected T-cell or NK-cell proliferation, especially in East Asian populations.^3,5

Epstein-Barr virus–positive T-cell and NK-cell LPDs of childhood include CAEBV infection of T-cell and NK-cell types and systemic EBV-positive T-cell lymphoma of childhood. The former includes hydroa vacciniforme–like LPD and severe mosquito bite allergy.³

Systemic EBV-Positive T-cell Lymphoma of Childhood
This entity occurs not only in children but also in adolescents and young adults. A fulminant illness characterized by clonal proliferation of EBV-infected cytotoxic T cells, it can develop shortly after primary EBV infection or is linked to CAEBV infection. The disorder is rare and has a racial predilection for Asian (ie, Japanese, Chinese, Korean) populations and indigenous populations of Mexico and Central and South America.^6-8

Complications
Systemic EBV-positive T-cell lymphoma of childhood is often complicated by hemophagocytic syndrome, coagulopathy, sepsis, and multiorgan failure. Other signs and symptoms include high fever, rash, jaundice, diarrhea, pancytopenia, and hepatosplenomegaly. The liver, spleen, lymph nodes, and bone marrow are commonly involved, and the disease can involve skin, the heart, and the lungs.^9,10

Diagnosis
When systemic EBV-positive T-cell lymphoma occurs shortly after IM, serology shows low or absent anti-VCA IgM and positive anti-VCA IgG. Infiltrating T cells usually are small and lack cytologic atypia; however, cases with pleomorphic, medium to large lymphoid cells, irregular nuclei, and frequent mitoses have been described. Hemophagocytosis can be seen in the liver, spleen, and bone marrow.^3,11

The most typical phenotype of systemic EBV-positive T-cell lymphoma is CD2⁺CD3⁺CD8⁺CD20⁻CD56⁻, with expression of the cytotoxic granules known as T-cell intracellular antigen 1 and granzyme B. Rare cases of CD4⁺ and mixed CD4⁺/CD8⁺ phenotypes have been described, usually in the setting of CAEBV infection.^3,12 Neoplastic cells have monoclonally rearranged TCR-γ genes and consistent EBER positivity with in situ hybridization.¹³ A final diagnosis is based on a comprehensive analysis of clinical, morphological, immunohistochemical, and molecular biological aspects.

Clinical Course and Prognosis
Most patients with systemic EBV-positive T-cell lymphoma have an aggressive clinical course with high mortality. In a few cases, patients were reported to respond to a regimen of etoposide and dexamethasone, followed by allogeneic hematopoietic stem cell transplantation.³

In recognition of the aggressive clinical behavior and desire to clearly distinguish systemic EBV-positive T-cell lymphoma from CAEBV infection, the older term systemic EBV-positive T-cell LPD of childhood, which had been introduced in 2008 to the World Health Organization classification, was changed to systemic EBV-positive T-cell lymphoma of childhood in the revised 2016 World Health Organization classification.^6,12 However, Kim et al¹⁴ reported a case with excellent response to corticosteroid administration, suggesting that systemic EBV-positive T-cell lymphoma of childhood may be more heterogeneous in terms of prognosis.

Our patient presented with acute IM-like symptoms, including high fever, tonsillar enlargement, lymphadenopathy, and hepatosplenomegaly, as well as uncommon oral ulcers and skin lesions, including indurated nodules. Histopathologic changes in the skin nodule, proliferation in bone marrow, immunohistochemical phenotype, and positivity of EBER and TCR-γ monoclonal rearrangement were all consistent with systemic EBV-positive T-cell lymphoma of childhood. The patient was positive for VCA IgG and negative for VCA IgM, compatible with systemic EBV-positive T-cell lymphoma of childhood occurring shortly after IM. Neither pancytopenia, hemophagocytic syndrome, nor multiorgan failure occurred during the course.

Differential Diagnosis
It is important to distinguish IM from systemic EBV-positive T-cell lymphoma of childhood and CAEBV infection. Detection of anti–VCA IgM in the early stage, its disappearance during the clinical course, and appearance of anti-EBV–determined nuclear antigen is useful to distinguish IM from the neoplasms, as systemic EBV-positive T-cell lymphoma of childhood is negative for anti-EBV–determined nuclear antigen. Carefully following the clinical course also is important.^3,15

Epstein-Barr virus–associated hemophagocytic lymphohistiocytosis can occur in association with systemic EBV-positive T-cell lymphoma of childhood and might represent a continuum of disease rather than distinct entities.¹⁴ The most useful marker for differentiating EBV-associated hemophagocytic lymphohistiocytosis and systemic EBV-positive T-cell lymphoma of childhood is an abnormal karyotype rather than molecular clonality.¹⁶

Outcome
Mortality risk in EBV-associated T-cell and NK-cell LPD is not primarily dependent on whether the lesion has progressed to lymphoma but instead is related to associated complications.¹⁷

Conclusion

Although systemic EBV-positive T-cell lymphoma of childhood is a rare disorder and has race predilection, dermatologists should be aware due to the aggressive clinical source and poor prognosis. Histopathology and in situ hybridization for EBER and TCR gene rearrangements are critical for final diagnosis. Although rare cases can show temporary resolution, the final outcome of this disease is not optimistic.

Classically, eczema herpeticum is associated with atopic dermatitis (AD), but it also has been previously reported in the setting of pemphigus vulgaris, Darier disease, ichthyosis vulgaris, burns, psoriasis, and irritant contact dermatitis.^1,2 Descriptions of cutaneous herpes simplex virus (HSV) in the setting of seborrheic dermatitis are lacking.

Case Report

A 2-month-old infant boy who was otherwise healthy presented to the emergency department with a new rash on the scalp. Initially there were a few clusters of small fluid-filled lesions that evolved over several days into diffuse clusters covering the scalp and extending onto the forehead and upper chest (Figure). The patient’s medical history was notable for infantile seborrheic dermatitis and a family history of AD. His grandmother, who was his primary caretaker, had a recent history of herpes labialis.

Physical examination revealed numerous discrete, erythematous, and punched-out erosions diffusely on the scalp. There were fewer similar erosions on the forehead and upper chest. There were no oral or periocular lesions. There were no areas of lichenification or eczematous plaques on the remainder of the trunk or extremities. Laboratory testing was positive for HSV type 1 polymerase chain reaction and positive for HSV type 1 viral culture. Liver enzymes were elevated with alanine aminotransferase at 107 U/L (reference range, 7–52 U/L) and aspartate aminotransferase at 94 U/L (reference range, 13–39 U/L).

The patient was admitted to the hospital and was treated by the dermatology and infectious disease services. Intravenous acyclovir 60 mg/kg daily was administered for 3 days until all lesions had crusted over. On the day of discharge, the patient was transitioned to oral valacyclovir 20 mg/kg daily for 7 days with resolution. One month later he developed a recurrence that was within his existing seborrheic dermatitis. After a repeat 7-day course of oral valacyclovir 20 mg/kg daily, he was placed on prophylaxis therapy of oral acyclovir 10 mg/kg daily. Gentle skin care precautions also were recommended.

Comment

Eczema herpeticum refers to disseminated cutaneous infection with HSV types 1 or 2 in the setting of underlying dermatosis.² Although it is classically associated with AD, it has been reported in a number of other chronic skin disorders and can lead to serious complications, including hepatitis, keratoconjunctivitis, and meningitis. In those with AD who develop HSV, presentation may occur in active dermatitis locations because of skin barrier disruption, which may lead to increased susceptibility to viral infection.³

Herpes simplex virus in a background of seborrheic dermatitis has not been well described. Although the pathogenesis of seborrheic dermatitis has not been fully reported, several gene mutations and protein deficiencies have been identified in patients and animal models that are associated with immune response or epidermal differentiation.⁴ Therefore, it is possible that, as with AD, a disruption in the skin barrier increases susceptibility to viral infection.

It also has been suggested that infantile seborrheic dermatitis and AD represent the same spectrum of disease.⁵ Given our patient’s family history of AD, it is possible his presentation represents early underlying AD. Providers should be aware that cutaneous HSV can be confined to a seborrheic distribution and may represent underlying epidermal dysfunction secondary to seborrheic dermatitis.

Classically, eczema herpeticum is associated with atopic dermatitis (AD), but it also has been previously reported in the setting of pemphigus vulgaris, Darier disease, ichthyosis vulgaris, burns, psoriasis, and irritant contact dermatitis.^1,2 Descriptions of cutaneous herpes simplex virus (HSV) in the setting of seborrheic dermatitis are lacking.

Case Report

A 2-month-old infant boy who was otherwise healthy presented to the emergency department with a new rash on the scalp. Initially there were a few clusters of small fluid-filled lesions that evolved over several days into diffuse clusters covering the scalp and extending onto the forehead and upper chest (Figure). The patient’s medical history was notable for infantile seborrheic dermatitis and a family history of AD. His grandmother, who was his primary caretaker, had a recent history of herpes labialis.

Physical examination revealed numerous discrete, erythematous, and punched-out erosions diffusely on the scalp. There were fewer similar erosions on the forehead and upper chest. There were no oral or periocular lesions. There were no areas of lichenification or eczematous plaques on the remainder of the trunk or extremities. Laboratory testing was positive for HSV type 1 polymerase chain reaction and positive for HSV type 1 viral culture. Liver enzymes were elevated with alanine aminotransferase at 107 U/L (reference range, 7–52 U/L) and aspartate aminotransferase at 94 U/L (reference range, 13–39 U/L).

The patient was admitted to the hospital and was treated by the dermatology and infectious disease services. Intravenous acyclovir 60 mg/kg daily was administered for 3 days until all lesions had crusted over. On the day of discharge, the patient was transitioned to oral valacyclovir 20 mg/kg daily for 7 days with resolution. One month later he developed a recurrence that was within his existing seborrheic dermatitis. After a repeat 7-day course of oral valacyclovir 20 mg/kg daily, he was placed on prophylaxis therapy of oral acyclovir 10 mg/kg daily. Gentle skin care precautions also were recommended.

Comment

Eczema herpeticum refers to disseminated cutaneous infection with HSV types 1 or 2 in the setting of underlying dermatosis.² Although it is classically associated with AD, it has been reported in a number of other chronic skin disorders and can lead to serious complications, including hepatitis, keratoconjunctivitis, and meningitis. In those with AD who develop HSV, presentation may occur in active dermatitis locations because of skin barrier disruption, which may lead to increased susceptibility to viral infection.³

Herpes simplex virus in a background of seborrheic dermatitis has not been well described. Although the pathogenesis of seborrheic dermatitis has not been fully reported, several gene mutations and protein deficiencies have been identified in patients and animal models that are associated with immune response or epidermal differentiation.⁴ Therefore, it is possible that, as with AD, a disruption in the skin barrier increases susceptibility to viral infection.

It also has been suggested that infantile seborrheic dermatitis and AD represent the same spectrum of disease.⁵ Given our patient’s family history of AD, it is possible his presentation represents early underlying AD. Providers should be aware that cutaneous HSV can be confined to a seborrheic distribution and may represent underlying epidermal dysfunction secondary to seborrheic dermatitis.

Classically, eczema herpeticum is associated with atopic dermatitis (AD), but it also has been previously reported in the setting of pemphigus vulgaris, Darier disease, ichthyosis vulgaris, burns, psoriasis, and irritant contact dermatitis.^1,2 Descriptions of cutaneous herpes simplex virus (HSV) in the setting of seborrheic dermatitis are lacking.

Case Report

A 2-month-old infant boy who was otherwise healthy presented to the emergency department with a new rash on the scalp. Initially there were a few clusters of small fluid-filled lesions that evolved over several days into diffuse clusters covering the scalp and extending onto the forehead and upper chest (Figure). The patient’s medical history was notable for infantile seborrheic dermatitis and a family history of AD. His grandmother, who was his primary caretaker, had a recent history of herpes labialis.

Physical examination revealed numerous discrete, erythematous, and punched-out erosions diffusely on the scalp. There were fewer similar erosions on the forehead and upper chest. There were no oral or periocular lesions. There were no areas of lichenification or eczematous plaques on the remainder of the trunk or extremities. Laboratory testing was positive for HSV type 1 polymerase chain reaction and positive for HSV type 1 viral culture. Liver enzymes were elevated with alanine aminotransferase at 107 U/L (reference range, 7–52 U/L) and aspartate aminotransferase at 94 U/L (reference range, 13–39 U/L).

The patient was admitted to the hospital and was treated by the dermatology and infectious disease services. Intravenous acyclovir 60 mg/kg daily was administered for 3 days until all lesions had crusted over. On the day of discharge, the patient was transitioned to oral valacyclovir 20 mg/kg daily for 7 days with resolution. One month later he developed a recurrence that was within his existing seborrheic dermatitis. After a repeat 7-day course of oral valacyclovir 20 mg/kg daily, he was placed on prophylaxis therapy of oral acyclovir 10 mg/kg daily. Gentle skin care precautions also were recommended.

Comment

Eczema herpeticum refers to disseminated cutaneous infection with HSV types 1 or 2 in the setting of underlying dermatosis.² Although it is classically associated with AD, it has been reported in a number of other chronic skin disorders and can lead to serious complications, including hepatitis, keratoconjunctivitis, and meningitis. In those with AD who develop HSV, presentation may occur in active dermatitis locations because of skin barrier disruption, which may lead to increased susceptibility to viral infection.³

Herpes simplex virus in a background of seborrheic dermatitis has not been well described. Although the pathogenesis of seborrheic dermatitis has not been fully reported, several gene mutations and protein deficiencies have been identified in patients and animal models that are associated with immune response or epidermal differentiation.⁴ Therefore, it is possible that, as with AD, a disruption in the skin barrier increases susceptibility to viral infection.

It also has been suggested that infantile seborrheic dermatitis and AD represent the same spectrum of disease.⁵ Given our patient’s family history of AD, it is possible his presentation represents early underlying AD. Providers should be aware that cutaneous HSV can be confined to a seborrheic distribution and may represent underlying epidermal dysfunction secondary to seborrheic dermatitis.

Molluscum contagiosum virus (MCV) infection causes the cutaneous lesions we call molluscum. Molluscum has become common in the last 30 years. Deciding the best course of therapy requires some fundamental understanding about how MCV relates to the following factors: epidemiology, childhood immunity and vaccination, clinical features, comorbidities, and quality of life. Treatment depends on many factors, including presence or absence of atopic dermatitis (AD) and/or pruritus, other symptoms, cosmetic location, and the child’s concern about the lesions. Therapeutics include destructive and immunologic therapies, the latter geared toward increasing immune response.

Epidemiology

Molluscum contagiosum virus is the solo member of the Molluscipoxvirus genus. Infection with MCV causes benign growth or tumors in the skin (ie, molluscum). The infection is slow to clear because the virus reduces the host’s immunity.^1,2 Molluscum contagiosum virus is a double-stranded DNA virus that affects keratinocytes and genetically carries the tools for its own replication (ie, DNA-dependent RNA polymerase). The virus has a few subtypes—I/Ia, II, III, and IV—with MCV-I predominating in children and healthy humans and MCV-II in patients with human immunodeficiency virus.^1,2 Typing is experimental and is not standardly performed in clinical practice. Molluscum contagiosum virus produces a variety of factors that block the host’s immune response, prolonging infection and preventing erythema and inflammatory response.³

Molluscum contagiosum virus is transmitted through skin-to-skin contact and fomites, including shared towels, bathtubs, spas, bath sponges, and pool equipment.^2,4,5 Transmission from household contact and bathing together has been noted in pediatric patients with MCV. Based on the data it can be posited that the lesions are softer when wet and more readily release viral particles or fomites, and fomites may be left on surfaces, especially when a child is wet.^6,7 Propensity for infection occurs in patients with AD and in immunosuppressed hosts, including children with human immunodeficiency virus and iatrogenic immunosuppression caused by chemotherapy.^1,2,8 Contact sports can increase the risk of transmission, and outbreaks have occurred in pools,^5,9 day-care facilities,¹⁰ and sports settings.¹¹ Cases of congenital and vertically transmitted molluscum have been documented.^12,13 Sexual transmission of MCV may be seen in adolescents who are sexually active. Although child-to-child transmission can occur in the groin area from shared equipment, transmission via sexual abuse also is possible.¹⁴ Bargman¹⁵ has mentioned the isolated genital location and lack of contact with other infected children as concerning features. Latency of new lesion appearance is anywhere from 1 to 50 days from the date of inoculation; therefore, new lesions are possible and expected even after therapy has been effective in eradicating visible lesions.¹⁰ Although clearance has been reported in 6 to 12 months, one pediatric study demonstrated 70% clearance by 1.5 years, suggesting the disease often is more prolonged.¹⁶ One-third of children will experience signs of inflammation, such as pruritus and/or erythema. Rare side effects include bacterial superinfection and hypersensitivity.²

One Dutch study from 1994, the largest database survey of children to date, cited a 17% cumulative incidence of molluscum in children by reviewing the data from 103 general practices.¹⁷ In a survey and review of molluscum by Braue et al,¹⁸ annual rates in populations vary but seem to maximize at approximately 6% to 7%. Sturt et al¹⁹ reviewed the prevalence in the indigenous West Sepik section of New Guinea and noted annual incidence rates of 6% in children younger than 10 years (range, 1.8%–10.9%). Epidemics occur and can produce large numbers of cases in a short time period.¹⁸ The cumulative prevalence in early childhood may be as high as 22%, as Sturt et al¹⁹ observed in children younger than 10 years.

Rising incidence and therefore rising lifetime prevalence appear to have been an issue in the last few decades. Data from the Indian Health Service have demonstrated increases in MCV in Native American children between 2001 and 2005.²⁰ In adults, the data support a steady increase of molluscum from 1988-2007, with a 3-fold increase from 1988-1997 to 1998-2007 in a Spanish study.²¹ Better population-based data are needed.

Childhood Immunity and Vaccination

Sequence homology between MC133L, a protein of MCV, with vaccinia virus suggests overlapping genes.²² Therefore, it is conceptually possible that the rise in incidence of MCV since the 1980s relates to the loss of herd immunity to variola due to lack of vaccination for smallpox, which has not been offered in the United States since 1972.²³ Childhood immunity to MCV varies among studies, but it appears that children do develop antibodies to molluscum in the setting of forming an immune response. Because the rise in molluscum incidence began after the smallpox vaccine was discontinued, the factors appear related; however, the scientific data do not support the theory of a relationship. Mitchell²⁴ has shown that a patient can develop antibodies in response to ground molluscum bodies inoculated into the skin; however, vaccination against molluscum and natural infection do not appear to produce antibodies that would cross-react and protect against other poxviruses, including vaccinia or fowl pox infections.²⁵ Cell-mediated immunity also is required to clear MCV and may account for the inflammatory appearance of lesions as they resolve.²⁶

Demonstrated factors that account for the rise in MCV incidence, aside from alterations in vaccination practices, include spread through sports,⁹ swimming,¹¹ and AD,⁷ which have become more commonplace in the United States in the last few decades, supporting the theory that they may be the cause of the increase in childhood MCV infections. Another cause may be the ability of MCV to create factors that stem host immune response.¹

Clinical Features

Molluscum lesions have a typical appearance of pearly papules with a central dell. These lesions are lighter to flesh colored and measure 1 to 3 mm.^2,4,5 The lesions cluster in the axillae and extremities and average from 10 to 20 per child.⁶ Lesions clear spontaneously, but new ones will continue to form until immunity is developed. Specific clinical appearances of lesions that are not pearly papules are not infrequent. Table 1 contains a short list of the manifold clinical appearances of molluscum lesions in children.^1,2,7,27-35 In particular, certain clinical appearances should be considered. In small children, head and neck lesions resembling milia are not uncommon. Giant or wartlike lesions can appear on the head, neck, or gluteal region in children and are clinical mimics of condyloma or other warts (Figure 1). Giant lesions also can grow in the subcutaneous space and mimic a cyst or abscess.²⁷ Erosive lesions mimicking eczema vaccinatum can be seen (Figure 2), but dermoscopy may demonstrate central dells in some lesions. Other viral processes mimicked include Gianotti Crosti–like lesions (Figure 3) that appear when a papular id reaction forms over the extremities or a localized version in the axilla, mimicking unilateral laterothoracic exanthema.^2,36,37 Hypersensitivity reactions are commonly noted with clearance and can be papular or demonstrate swelling and erythema, termed the beginning-of-the-end sign.³⁸

Pruritus, erythema, and swelling can occur with clearance but do not appear in all patients. Addressing pruritus is important to prevent disease spread, as patients are likely to inoculate other areas of the skin with virus when they scratch, and lesion number is reduced with dermatitis interventions.³⁶

Comorbidities

Molluscum lesions can occur in any child; however, the impaired immunologic status and skin barrier in patients with AD is ripe for the extensive spread of lesions that is associated with higher lesion count.³⁶ Children with molluscum infection can experience new-onset dermatitis or triggering of AD flares, especially on the extremities, such as the antecubital and popliteal regions.⁷ A study of children with MCV infection demonstrated that treatment of active dermatitis reduced spread. The authors mentioned autoinoculation as the mechanism; however, these data also suggest supporting barrier state as a factor in disease spread.³⁶ Superinfection can occur prior to⁶ or after therapy for lesions,³⁷ but it is unclear if this relates to the underlying atopic diathesis. Children with molluscum have been described to have warts, psoriasis, family history of atopy, diabetes mellitus, and pityriasis alba,⁷ while immunosuppression of any kind is associated with molluscum and high lesion count or prolonged disease in childhood.^1,2

Quality of Life

Children with molluscum who have higher lesion counts appear to be at risk for severe effects on their quality of life. Approximately 10% of children with MCV infection have been documented to have severe impairments on quality of life.³⁹ In my practice, quality of life in children with MCV appears to be affected by many factors (Table 2).^7,18,39

Treatments

Proper Skin Care and Treatment of AD
Therapy for AD and/or pruritus appears to limit lesion number in children with MCV and rashes or itch.^7,36 I recommend barrier repair agents, including emollients and syndet bar cleansers, to prevent small breaks in the skin that occur with xerosis and AD and that increase itch and risk of spread. Therapy for AD and molluscum dermatitis is similar and overlapping. There is always a concern about the spread of MCV when using topical calcineurin inhibitors. I, therefore, focus the dermatitis therapeutics on topical corticosteroid–based care.^6,40

Prevention of Spread
Prevention of spread begins with hygiene interventions. Cobathing is common in children with MCV and should be held off when possible. It is important for the child with MCV to avoid sharing bath towels and equipment²³ and having bare skin come in contact with mats in sports. I request that children with MCV wear bathing suits that cover the areas affected.

Reassurance
The most important therapy is reassurance.⁴¹ Many parents/guardians are truly unaware that the MCV infection can last for more than a year and therefore worry over normal disease course. When counseled as to the benign course of illness and given instructions on proper skin care, the parent/guardian of a child with MCV will often opt against therapy of uncomplicated cases. On the other hand, there are medical reasons for treatment, and they support the need for intervention (Table 3). Seventy percent of lesions resolve in 1.5 years; however, of the residual infections, some may last as long as 4 years.¹⁶ It is not recommended to stop children from attending school because of MCV.

Conclusion

Molluscum is a cutaneous viral infection that is common in children and has associated morbidities, including AD, pruritus, poor quality of life in some cases, and risk of contagion. Addressing the disease includes understanding its natural history and explaining it to parents/guardians. Therapeutics can be offered in cases where need is demonstrated, such as with lesions that spread and cause discomfort. Choice of therapeutics depends on the practitioner’s experience, the child’s clinical appearance, availability of therapy, and review of options with the parents/guardians. When avoidance of intervention is desired, barrier enhancement and treatment of symptomatic dermatitis are still beneficial, as are household (eg, not sharing towels) and activity (eg, adhesive bandages over active lesions) interventions to reduce transmission.

Molluscum contagiosum virus (MCV) infection causes the cutaneous lesions we call molluscum. Molluscum has become common in the last 30 years. Deciding the best course of therapy requires some fundamental understanding about how MCV relates to the following factors: epidemiology, childhood immunity and vaccination, clinical features, comorbidities, and quality of life. Treatment depends on many factors, including presence or absence of atopic dermatitis (AD) and/or pruritus, other symptoms, cosmetic location, and the child’s concern about the lesions. Therapeutics include destructive and immunologic therapies, the latter geared toward increasing immune response.

Epidemiology

Molluscum contagiosum virus is the solo member of the Molluscipoxvirus genus. Infection with MCV causes benign growth or tumors in the skin (ie, molluscum). The infection is slow to clear because the virus reduces the host’s immunity.^1,2 Molluscum contagiosum virus is a double-stranded DNA virus that affects keratinocytes and genetically carries the tools for its own replication (ie, DNA-dependent RNA polymerase). The virus has a few subtypes—I/Ia, II, III, and IV—with MCV-I predominating in children and healthy humans and MCV-II in patients with human immunodeficiency virus.^1,2 Typing is experimental and is not standardly performed in clinical practice. Molluscum contagiosum virus produces a variety of factors that block the host’s immune response, prolonging infection and preventing erythema and inflammatory response.³

Molluscum contagiosum virus is transmitted through skin-to-skin contact and fomites, including shared towels, bathtubs, spas, bath sponges, and pool equipment.^2,4,5 Transmission from household contact and bathing together has been noted in pediatric patients with MCV. Based on the data it can be posited that the lesions are softer when wet and more readily release viral particles or fomites, and fomites may be left on surfaces, especially when a child is wet.^6,7 Propensity for infection occurs in patients with AD and in immunosuppressed hosts, including children with human immunodeficiency virus and iatrogenic immunosuppression caused by chemotherapy.^1,2,8 Contact sports can increase the risk of transmission, and outbreaks have occurred in pools,^5,9 day-care facilities,¹⁰ and sports settings.¹¹ Cases of congenital and vertically transmitted molluscum have been documented.^12,13 Sexual transmission of MCV may be seen in adolescents who are sexually active. Although child-to-child transmission can occur in the groin area from shared equipment, transmission via sexual abuse also is possible.¹⁴ Bargman¹⁵ has mentioned the isolated genital location and lack of contact with other infected children as concerning features. Latency of new lesion appearance is anywhere from 1 to 50 days from the date of inoculation; therefore, new lesions are possible and expected even after therapy has been effective in eradicating visible lesions.¹⁰ Although clearance has been reported in 6 to 12 months, one pediatric study demonstrated 70% clearance by 1.5 years, suggesting the disease often is more prolonged.¹⁶ One-third of children will experience signs of inflammation, such as pruritus and/or erythema. Rare side effects include bacterial superinfection and hypersensitivity.²

One Dutch study from 1994, the largest database survey of children to date, cited a 17% cumulative incidence of molluscum in children by reviewing the data from 103 general practices.¹⁷ In a survey and review of molluscum by Braue et al,¹⁸ annual rates in populations vary but seem to maximize at approximately 6% to 7%. Sturt et al¹⁹ reviewed the prevalence in the indigenous West Sepik section of New Guinea and noted annual incidence rates of 6% in children younger than 10 years (range, 1.8%–10.9%). Epidemics occur and can produce large numbers of cases in a short time period.¹⁸ The cumulative prevalence in early childhood may be as high as 22%, as Sturt et al¹⁹ observed in children younger than 10 years.

Rising incidence and therefore rising lifetime prevalence appear to have been an issue in the last few decades. Data from the Indian Health Service have demonstrated increases in MCV in Native American children between 2001 and 2005.²⁰ In adults, the data support a steady increase of molluscum from 1988-2007, with a 3-fold increase from 1988-1997 to 1998-2007 in a Spanish study.²¹ Better population-based data are needed.

Childhood Immunity and Vaccination

Sequence homology between MC133L, a protein of MCV, with vaccinia virus suggests overlapping genes.²² Therefore, it is conceptually possible that the rise in incidence of MCV since the 1980s relates to the loss of herd immunity to variola due to lack of vaccination for smallpox, which has not been offered in the United States since 1972.²³ Childhood immunity to MCV varies among studies, but it appears that children do develop antibodies to molluscum in the setting of forming an immune response. Because the rise in molluscum incidence began after the smallpox vaccine was discontinued, the factors appear related; however, the scientific data do not support the theory of a relationship. Mitchell²⁴ has shown that a patient can develop antibodies in response to ground molluscum bodies inoculated into the skin; however, vaccination against molluscum and natural infection do not appear to produce antibodies that would cross-react and protect against other poxviruses, including vaccinia or fowl pox infections.²⁵ Cell-mediated immunity also is required to clear MCV and may account for the inflammatory appearance of lesions as they resolve.²⁶

Demonstrated factors that account for the rise in MCV incidence, aside from alterations in vaccination practices, include spread through sports,⁹ swimming,¹¹ and AD,⁷ which have become more commonplace in the United States in the last few decades, supporting the theory that they may be the cause of the increase in childhood MCV infections. Another cause may be the ability of MCV to create factors that stem host immune response.¹

Clinical Features

Molluscum lesions have a typical appearance of pearly papules with a central dell. These lesions are lighter to flesh colored and measure 1 to 3 mm.^2,4,5 The lesions cluster in the axillae and extremities and average from 10 to 20 per child.⁶ Lesions clear spontaneously, but new ones will continue to form until immunity is developed. Specific clinical appearances of lesions that are not pearly papules are not infrequent. Table 1 contains a short list of the manifold clinical appearances of molluscum lesions in children.^1,2,7,27-35 In particular, certain clinical appearances should be considered. In small children, head and neck lesions resembling milia are not uncommon. Giant or wartlike lesions can appear on the head, neck, or gluteal region in children and are clinical mimics of condyloma or other warts (Figure 1). Giant lesions also can grow in the subcutaneous space and mimic a cyst or abscess.²⁷ Erosive lesions mimicking eczema vaccinatum can be seen (Figure 2), but dermoscopy may demonstrate central dells in some lesions. Other viral processes mimicked include Gianotti Crosti–like lesions (Figure 3) that appear when a papular id reaction forms over the extremities or a localized version in the axilla, mimicking unilateral laterothoracic exanthema.^2,36,37 Hypersensitivity reactions are commonly noted with clearance and can be papular or demonstrate swelling and erythema, termed the beginning-of-the-end sign.³⁸

Pruritus, erythema, and swelling can occur with clearance but do not appear in all patients. Addressing pruritus is important to prevent disease spread, as patients are likely to inoculate other areas of the skin with virus when they scratch, and lesion number is reduced with dermatitis interventions.³⁶

Comorbidities

Molluscum lesions can occur in any child; however, the impaired immunologic status and skin barrier in patients with AD is ripe for the extensive spread of lesions that is associated with higher lesion count.³⁶ Children with molluscum infection can experience new-onset dermatitis or triggering of AD flares, especially on the extremities, such as the antecubital and popliteal regions.⁷ A study of children with MCV infection demonstrated that treatment of active dermatitis reduced spread. The authors mentioned autoinoculation as the mechanism; however, these data also suggest supporting barrier state as a factor in disease spread.³⁶ Superinfection can occur prior to⁶ or after therapy for lesions,³⁷ but it is unclear if this relates to the underlying atopic diathesis. Children with molluscum have been described to have warts, psoriasis, family history of atopy, diabetes mellitus, and pityriasis alba,⁷ while immunosuppression of any kind is associated with molluscum and high lesion count or prolonged disease in childhood.^1,2

Quality of Life

Children with molluscum who have higher lesion counts appear to be at risk for severe effects on their quality of life. Approximately 10% of children with MCV infection have been documented to have severe impairments on quality of life.³⁹ In my practice, quality of life in children with MCV appears to be affected by many factors (Table 2).^7,18,39

Treatments

Proper Skin Care and Treatment of AD
Therapy for AD and/or pruritus appears to limit lesion number in children with MCV and rashes or itch.^7,36 I recommend barrier repair agents, including emollients and syndet bar cleansers, to prevent small breaks in the skin that occur with xerosis and AD and that increase itch and risk of spread. Therapy for AD and molluscum dermatitis is similar and overlapping. There is always a concern about the spread of MCV when using topical calcineurin inhibitors. I, therefore, focus the dermatitis therapeutics on topical corticosteroid–based care.^6,40

Prevention of Spread
Prevention of spread begins with hygiene interventions. Cobathing is common in children with MCV and should be held off when possible. It is important for the child with MCV to avoid sharing bath towels and equipment²³ and having bare skin come in contact with mats in sports. I request that children with MCV wear bathing suits that cover the areas affected.

Reassurance
The most important therapy is reassurance.⁴¹ Many parents/guardians are truly unaware that the MCV infection can last for more than a year and therefore worry over normal disease course. When counseled as to the benign course of illness and given instructions on proper skin care, the parent/guardian of a child with MCV will often opt against therapy of uncomplicated cases. On the other hand, there are medical reasons for treatment, and they support the need for intervention (Table 3). Seventy percent of lesions resolve in 1.5 years; however, of the residual infections, some may last as long as 4 years.¹⁶ It is not recommended to stop children from attending school because of MCV.

Conclusion

Molluscum is a cutaneous viral infection that is common in children and has associated morbidities, including AD, pruritus, poor quality of life in some cases, and risk of contagion. Addressing the disease includes understanding its natural history and explaining it to parents/guardians. Therapeutics can be offered in cases where need is demonstrated, such as with lesions that spread and cause discomfort. Choice of therapeutics depends on the practitioner’s experience, the child’s clinical appearance, availability of therapy, and review of options with the parents/guardians. When avoidance of intervention is desired, barrier enhancement and treatment of symptomatic dermatitis are still beneficial, as are household (eg, not sharing towels) and activity (eg, adhesive bandages over active lesions) interventions to reduce transmission.

Molluscum contagiosum virus (MCV) infection causes the cutaneous lesions we call molluscum. Molluscum has become common in the last 30 years. Deciding the best course of therapy requires some fundamental understanding about how MCV relates to the following factors: epidemiology, childhood immunity and vaccination, clinical features, comorbidities, and quality of life. Treatment depends on many factors, including presence or absence of atopic dermatitis (AD) and/or pruritus, other symptoms, cosmetic location, and the child’s concern about the lesions. Therapeutics include destructive and immunologic therapies, the latter geared toward increasing immune response.

Epidemiology

Molluscum contagiosum virus is the solo member of the Molluscipoxvirus genus. Infection with MCV causes benign growth or tumors in the skin (ie, molluscum). The infection is slow to clear because the virus reduces the host’s immunity.^1,2 Molluscum contagiosum virus is a double-stranded DNA virus that affects keratinocytes and genetically carries the tools for its own replication (ie, DNA-dependent RNA polymerase). The virus has a few subtypes—I/Ia, II, III, and IV—with MCV-I predominating in children and healthy humans and MCV-II in patients with human immunodeficiency virus.^1,2 Typing is experimental and is not standardly performed in clinical practice. Molluscum contagiosum virus produces a variety of factors that block the host’s immune response, prolonging infection and preventing erythema and inflammatory response.³

Molluscum contagiosum virus is transmitted through skin-to-skin contact and fomites, including shared towels, bathtubs, spas, bath sponges, and pool equipment.^2,4,5 Transmission from household contact and bathing together has been noted in pediatric patients with MCV. Based on the data it can be posited that the lesions are softer when wet and more readily release viral particles or fomites, and fomites may be left on surfaces, especially when a child is wet.^6,7 Propensity for infection occurs in patients with AD and in immunosuppressed hosts, including children with human immunodeficiency virus and iatrogenic immunosuppression caused by chemotherapy.^1,2,8 Contact sports can increase the risk of transmission, and outbreaks have occurred in pools,^5,9 day-care facilities,¹⁰ and sports settings.¹¹ Cases of congenital and vertically transmitted molluscum have been documented.^12,13 Sexual transmission of MCV may be seen in adolescents who are sexually active. Although child-to-child transmission can occur in the groin area from shared equipment, transmission via sexual abuse also is possible.¹⁴ Bargman¹⁵ has mentioned the isolated genital location and lack of contact with other infected children as concerning features. Latency of new lesion appearance is anywhere from 1 to 50 days from the date of inoculation; therefore, new lesions are possible and expected even after therapy has been effective in eradicating visible lesions.¹⁰ Although clearance has been reported in 6 to 12 months, one pediatric study demonstrated 70% clearance by 1.5 years, suggesting the disease often is more prolonged.¹⁶ One-third of children will experience signs of inflammation, such as pruritus and/or erythema. Rare side effects include bacterial superinfection and hypersensitivity.²

One Dutch study from 1994, the largest database survey of children to date, cited a 17% cumulative incidence of molluscum in children by reviewing the data from 103 general practices.¹⁷ In a survey and review of molluscum by Braue et al,¹⁸ annual rates in populations vary but seem to maximize at approximately 6% to 7%. Sturt et al¹⁹ reviewed the prevalence in the indigenous West Sepik section of New Guinea and noted annual incidence rates of 6% in children younger than 10 years (range, 1.8%–10.9%). Epidemics occur and can produce large numbers of cases in a short time period.¹⁸ The cumulative prevalence in early childhood may be as high as 22%, as Sturt et al¹⁹ observed in children younger than 10 years.

Rising incidence and therefore rising lifetime prevalence appear to have been an issue in the last few decades. Data from the Indian Health Service have demonstrated increases in MCV in Native American children between 2001 and 2005.²⁰ In adults, the data support a steady increase of molluscum from 1988-2007, with a 3-fold increase from 1988-1997 to 1998-2007 in a Spanish study.²¹ Better population-based data are needed.

Childhood Immunity and Vaccination

Sequence homology between MC133L, a protein of MCV, with vaccinia virus suggests overlapping genes.²² Therefore, it is conceptually possible that the rise in incidence of MCV since the 1980s relates to the loss of herd immunity to variola due to lack of vaccination for smallpox, which has not been offered in the United States since 1972.²³ Childhood immunity to MCV varies among studies, but it appears that children do develop antibodies to molluscum in the setting of forming an immune response. Because the rise in molluscum incidence began after the smallpox vaccine was discontinued, the factors appear related; however, the scientific data do not support the theory of a relationship. Mitchell²⁴ has shown that a patient can develop antibodies in response to ground molluscum bodies inoculated into the skin; however, vaccination against molluscum and natural infection do not appear to produce antibodies that would cross-react and protect against other poxviruses, including vaccinia or fowl pox infections.²⁵ Cell-mediated immunity also is required to clear MCV and may account for the inflammatory appearance of lesions as they resolve.²⁶

Demonstrated factors that account for the rise in MCV incidence, aside from alterations in vaccination practices, include spread through sports,⁹ swimming,¹¹ and AD,⁷ which have become more commonplace in the United States in the last few decades, supporting the theory that they may be the cause of the increase in childhood MCV infections. Another cause may be the ability of MCV to create factors that stem host immune response.¹

Clinical Features

Molluscum lesions have a typical appearance of pearly papules with a central dell. These lesions are lighter to flesh colored and measure 1 to 3 mm.^2,4,5 The lesions cluster in the axillae and extremities and average from 10 to 20 per child.⁶ Lesions clear spontaneously, but new ones will continue to form until immunity is developed. Specific clinical appearances of lesions that are not pearly papules are not infrequent. Table 1 contains a short list of the manifold clinical appearances of molluscum lesions in children.^1,2,7,27-35 In particular, certain clinical appearances should be considered. In small children, head and neck lesions resembling milia are not uncommon. Giant or wartlike lesions can appear on the head, neck, or gluteal region in children and are clinical mimics of condyloma or other warts (Figure 1). Giant lesions also can grow in the subcutaneous space and mimic a cyst or abscess.²⁷ Erosive lesions mimicking eczema vaccinatum can be seen (Figure 2), but dermoscopy may demonstrate central dells in some lesions. Other viral processes mimicked include Gianotti Crosti–like lesions (Figure 3) that appear when a papular id reaction forms over the extremities or a localized version in the axilla, mimicking unilateral laterothoracic exanthema.^2,36,37 Hypersensitivity reactions are commonly noted with clearance and can be papular or demonstrate swelling and erythema, termed the beginning-of-the-end sign.³⁸

Pruritus, erythema, and swelling can occur with clearance but do not appear in all patients. Addressing pruritus is important to prevent disease spread, as patients are likely to inoculate other areas of the skin with virus when they scratch, and lesion number is reduced with dermatitis interventions.³⁶

Comorbidities

Molluscum lesions can occur in any child; however, the impaired immunologic status and skin barrier in patients with AD is ripe for the extensive spread of lesions that is associated with higher lesion count.³⁶ Children with molluscum infection can experience new-onset dermatitis or triggering of AD flares, especially on the extremities, such as the antecubital and popliteal regions.⁷ A study of children with MCV infection demonstrated that treatment of active dermatitis reduced spread. The authors mentioned autoinoculation as the mechanism; however, these data also suggest supporting barrier state as a factor in disease spread.³⁶ Superinfection can occur prior to⁶ or after therapy for lesions,³⁷ but it is unclear if this relates to the underlying atopic diathesis. Children with molluscum have been described to have warts, psoriasis, family history of atopy, diabetes mellitus, and pityriasis alba,⁷ while immunosuppression of any kind is associated with molluscum and high lesion count or prolonged disease in childhood.^1,2

Quality of Life

Children with molluscum who have higher lesion counts appear to be at risk for severe effects on their quality of life. Approximately 10% of children with MCV infection have been documented to have severe impairments on quality of life.³⁹ In my practice, quality of life in children with MCV appears to be affected by many factors (Table 2).^7,18,39

Treatments

Proper Skin Care and Treatment of AD
Therapy for AD and/or pruritus appears to limit lesion number in children with MCV and rashes or itch.^7,36 I recommend barrier repair agents, including emollients and syndet bar cleansers, to prevent small breaks in the skin that occur with xerosis and AD and that increase itch and risk of spread. Therapy for AD and molluscum dermatitis is similar and overlapping. There is always a concern about the spread of MCV when using topical calcineurin inhibitors. I, therefore, focus the dermatitis therapeutics on topical corticosteroid–based care.^6,40

Prevention of Spread
Prevention of spread begins with hygiene interventions. Cobathing is common in children with MCV and should be held off when possible. It is important for the child with MCV to avoid sharing bath towels and equipment²³ and having bare skin come in contact with mats in sports. I request that children with MCV wear bathing suits that cover the areas affected.

Reassurance
The most important therapy is reassurance.⁴¹ Many parents/guardians are truly unaware that the MCV infection can last for more than a year and therefore worry over normal disease course. When counseled as to the benign course of illness and given instructions on proper skin care, the parent/guardian of a child with MCV will often opt against therapy of uncomplicated cases. On the other hand, there are medical reasons for treatment, and they support the need for intervention (Table 3). Seventy percent of lesions resolve in 1.5 years; however, of the residual infections, some may last as long as 4 years.¹⁶ It is not recommended to stop children from attending school because of MCV.

Conclusion

Molluscum is a cutaneous viral infection that is common in children and has associated morbidities, including AD, pruritus, poor quality of life in some cases, and risk of contagion. Addressing the disease includes understanding its natural history and explaining it to parents/guardians. Therapeutics can be offered in cases where need is demonstrated, such as with lesions that spread and cause discomfort. Choice of therapeutics depends on the practitioner’s experience, the child’s clinical appearance, availability of therapy, and review of options with the parents/guardians. When avoidance of intervention is desired, barrier enhancement and treatment of symptomatic dermatitis are still beneficial, as are household (eg, not sharing towels) and activity (eg, adhesive bandages over active lesions) interventions to reduce transmission.

The pediatric population has a unique product exposure profile due to the many care products specifically marketed for use in children. In fact, the prevalence of allergic contact dermatitis (ACD) in children may be as high as 24.5% in the United States.¹ In patch tested children, relevant positive reaction rates of 56.7% and 48% have been reported by the North American Contact Dermatitis Group and the Pediatric Contact Dermatitis Registry, respectively.^2,3 In this article, we provide an overview of current trends in pediatric patch testing as well as specific considerations in this patient population.

Patch Test Reactions in Children

Several publications have documented pediatric patch test reactions. The North American Contact Dermatitis Group reported patch test results in 883 children from the United States and Canada (2005-2012).² The most common reactions were nickel (28.1%), cobalt (12.3%), neomycin (7.1%), balsam of Peru (5.7%), lanolin (5.5%), and fragrance mix I (5.2%). When compared to adults, children were more likely to have relevant positive patch tests to nickel, cobalt, and compositae mix.² In comparison, data from the Pediatric Contact Dermatitis Registry showed that the most common reactions in 1142 children in the United States (2015-2016) were nickel (22%), fragrance mix I (11%), cobalt (9.1%), balsam of Peru (8.4%), neomycin (7.2%), and propylene glycol (6.8%).³

Allergen sensitivities may vary based on geographic region. In Spain, children showed the highest sensitivities to thiomersal (10.2%), cobalt (9.1%), colophony (9.1%), paraphenylenediamine (8.3%), mercury (7.9%), potassium dichromate (7.9%), and nickel (6.4%).⁴

Pediatric Patch Testing Pearls

History of Product Use
From diapers to drama club, pediatric exposures and sources of ACD are not the same as those seen in adults. Because obtaining a medical history from a toddler can be exasperating, the patient’s caregivers should be asked about potential exposures, ranging from personal care products and diapers to school activities, hobbies, and sports.^5,6 It is important to keep in mind that the patient’s primary caregiver may not be the only individual who applies products to the child.⁷

Application of Allergens
Children are not merely small adults, but they usually do have smaller backs than adult patients. This reduced surface area means that the patch tester must carefully select the allergens to be patch tested. For reference, the back of a typical 6-year-old child can fit 40 to 60 allergens during patch testing.⁸

Patch Test Chambers
In children, the use of plastic patch test chambers may be preferred over aluminum chambers. Children with persistent pruritic subcutaneous nodules induced by aluminum-based vaccines also may have delayed-type sensitivity reactions to aluminum.⁹ These patients could react to the aluminum present in some patch test chambers, making interpretation of the results difficult. The authors (A.R.A. and M.R.) typically use plastic chambers in the pediatric population.

Managing Expectations
As with other procedures in the pediatric population, patch testing can elicit emotions of fear, anxiety, and distrust. Video distraction and/or role-playing games may help capture the attention of children and can be particularly helpful during patch application. Children may be apprehensive about the term allergy testing if they are familiar with the term needle testing from previous allergies.⁵

Securing Patches
Young children can be quite active, posing another challenge for keeping patches in place. We recommend using extra tape to secure the patches in place on a child’s back. In addition, a large transparent film dressing (ie, 12×8 in) can be used if quick application is needed. For extra precaution, the use of a tight T-shirt or favorite onesie during the patch test process may be helpful, making it more difficult for little fingers to remove tape edges.

Duration of Patch Testing
Some authors have proposed application of patch tests for 24 hours in pediatric patients, as compared to 48 hours in adults.¹⁰ This recommendation is based on a theory that the reduced application period will decrease the risk for irritant reactions in pediatric patients.

Pediatric Patch Test Screening Series

A summary of the published screening series for patch testing in the pediatric population is provided (Table).

The T.R.U.E. Test (SmartPractice) is approved by the US Food and Drug Administration for use in patients 6 years and older¹¹; however, it may not adequately represent allergen exposures in the pediatric population. Brankov and Jacob¹⁴ found that 10 (40%) of their proposed top 25 pediatric allergens were not detected using the T.R.U.E. Test.

In 2014, the North American Pediatric Patch Test Series was proposed as a basic screening panel for children aged 6 to 12 years.¹² This series of 20 allergens was developed based on a literature review of pediatric patch test results and case reports as well as a database review. The authors proposed additional allergens to be considered based on patient history.¹²

More recently, a 2017 American Contact Dermatitis Society physician work group proposed the Pediatric Baseline Patch Test Series. This series of 38 allergens for children aged 6 to 18 years was developed based on expert consensus.⁸ Studies to determine the efficacy of this series have yet to be conducted, but it may have high sensitivity in detecting relevant allergens in children as demonstrated by a theoretical detection rate of 84%.¹⁴

There are 2 recommended patch test series for allergic diaper dermatitis.¹⁵ The first series focuses on 23 potential allergens found in wet wipes and topical diaper preparations. The second series contains 10 potential allergens found in diapers. These series contain common topical medications for children including corticosteroids, antimicrobials, and sensitizers specific to diapers such as rubbers and adhesives.¹⁵

Similar to adults, it may be difficult to designate one screening panel that can identify all relevant allergens in children; thus, it is always important to obtain a thorough exposure history and customize testing to suspected allergens and/or patient products based on history and clinical relevance.

Unique Pediatric Allergens

Hobbies
Sports gear such as shin guards and splints often contain allergens such as formaldehyde resin, thiuram mix, and dialkyl thioureas.¹⁶ Perioral dermatitis may be caused by musical instrument mouthpieces containing nickel.⁶

Preservatives
Commonly reported causes of ACD in children include methylisothiazolinone (MI) and methylchloroisothiazolinone (MCI) found in wet wipes. A 2016 analysis of diaper wipes showed a low prevalence of MI (6.3%) and MCI (1.6%) in these products, which may reflect the industry’s awareness of these potential allergens and a subsequent change in the preservatives they utilize.¹⁷ However, the prevalence of MCI/MI contact allergy may be on the rise due to the popularity of homemade slime, which is made from common household products such as laundry detergent, dishwashing soap, and liquid glue. The Pediatric Baseline Patch Test Series captures most of the potential allergens in these homemade slime recipes and is recommended for use in pediatric patients suspected of having dermatitis secondary to playing with slime.^8,18

Toilet Seat Dermatitis
Toilet seat dermatitis presents as a pruritic dermatitis on the posterior upper thighs and buttocks. Although most cases of toilet seat dermatitis are irritant rather than allergic, potential allergens include plastics, fragrances, and components of cleaning products. Thus, physicians should maintain a high index of suspicion for ACD to toilet seats.¹⁹

Fragrance and Natural Ingredients
A 2018 study evaluating personal care products marketed specifically for infants and children found that 55% of products (294/533) contained at least 1 common allergen, with fragrance being the most common (48% [255/533]). Other common allergens include betaines (18%), propylene glycol (9%), lanolin (6%), and MCI/MI (3%).²⁰ Caregivers should be advised against the myth that natural products are safer and less allergenic and should be provided with resources such as the Contact Allergen Management Program (CAMP) database (https://www.contactderm.org/resources/acds-camp) for safe alternative personal care products.

Metal Allergens
Nickel, the American Contact Dermatitis Society 2008 Allergen of the Year, is another common allergen that affects children. Nickel allergy, commonly thought to affect the ears due to jewelry and ear piercing, may actually be found in a wide range of daily items such as braces, eyeglasses, keys, zippers, school chairs, electronics, toys, and even food.^3,6,21,22 With increased use of electronics in children of all ages, nickel found in mobile phones and other devices may be of particular concern. Caregivers can use a case or cover for metallic-appearing electronics.

Final Interpretation

Pediatric ACD is common. With limited surface area for patch testing in children, we recommend customized panels based on patient history and exposure. It is important for clinicians to recognize the unique causes of ACD in children and develop age-appropriate management plans.

The pediatric population has a unique product exposure profile due to the many care products specifically marketed for use in children. In fact, the prevalence of allergic contact dermatitis (ACD) in children may be as high as 24.5% in the United States.¹ In patch tested children, relevant positive reaction rates of 56.7% and 48% have been reported by the North American Contact Dermatitis Group and the Pediatric Contact Dermatitis Registry, respectively.^2,3 In this article, we provide an overview of current trends in pediatric patch testing as well as specific considerations in this patient population.

Patch Test Reactions in Children

Several publications have documented pediatric patch test reactions. The North American Contact Dermatitis Group reported patch test results in 883 children from the United States and Canada (2005-2012).² The most common reactions were nickel (28.1%), cobalt (12.3%), neomycin (7.1%), balsam of Peru (5.7%), lanolin (5.5%), and fragrance mix I (5.2%). When compared to adults, children were more likely to have relevant positive patch tests to nickel, cobalt, and compositae mix.² In comparison, data from the Pediatric Contact Dermatitis Registry showed that the most common reactions in 1142 children in the United States (2015-2016) were nickel (22%), fragrance mix I (11%), cobalt (9.1%), balsam of Peru (8.4%), neomycin (7.2%), and propylene glycol (6.8%).³

Allergen sensitivities may vary based on geographic region. In Spain, children showed the highest sensitivities to thiomersal (10.2%), cobalt (9.1%), colophony (9.1%), paraphenylenediamine (8.3%), mercury (7.9%), potassium dichromate (7.9%), and nickel (6.4%).⁴

Pediatric Patch Testing Pearls

History of Product Use
From diapers to drama club, pediatric exposures and sources of ACD are not the same as those seen in adults. Because obtaining a medical history from a toddler can be exasperating, the patient’s caregivers should be asked about potential exposures, ranging from personal care products and diapers to school activities, hobbies, and sports.^5,6 It is important to keep in mind that the patient’s primary caregiver may not be the only individual who applies products to the child.⁷

Application of Allergens
Children are not merely small adults, but they usually do have smaller backs than adult patients. This reduced surface area means that the patch tester must carefully select the allergens to be patch tested. For reference, the back of a typical 6-year-old child can fit 40 to 60 allergens during patch testing.⁸

Patch Test Chambers
In children, the use of plastic patch test chambers may be preferred over aluminum chambers. Children with persistent pruritic subcutaneous nodules induced by aluminum-based vaccines also may have delayed-type sensitivity reactions to aluminum.⁹ These patients could react to the aluminum present in some patch test chambers, making interpretation of the results difficult. The authors (A.R.A. and M.R.) typically use plastic chambers in the pediatric population.

Managing Expectations
As with other procedures in the pediatric population, patch testing can elicit emotions of fear, anxiety, and distrust. Video distraction and/or role-playing games may help capture the attention of children and can be particularly helpful during patch application. Children may be apprehensive about the term allergy testing if they are familiar with the term needle testing from previous allergies.⁵

Securing Patches
Young children can be quite active, posing another challenge for keeping patches in place. We recommend using extra tape to secure the patches in place on a child’s back. In addition, a large transparent film dressing (ie, 12×8 in) can be used if quick application is needed. For extra precaution, the use of a tight T-shirt or favorite onesie during the patch test process may be helpful, making it more difficult for little fingers to remove tape edges.

Duration of Patch Testing
Some authors have proposed application of patch tests for 24 hours in pediatric patients, as compared to 48 hours in adults.¹⁰ This recommendation is based on a theory that the reduced application period will decrease the risk for irritant reactions in pediatric patients.

Pediatric Patch Test Screening Series

A summary of the published screening series for patch testing in the pediatric population is provided (Table).

The T.R.U.E. Test (SmartPractice) is approved by the US Food and Drug Administration for use in patients 6 years and older¹¹; however, it may not adequately represent allergen exposures in the pediatric population. Brankov and Jacob¹⁴ found that 10 (40%) of their proposed top 25 pediatric allergens were not detected using the T.R.U.E. Test.

In 2014, the North American Pediatric Patch Test Series was proposed as a basic screening panel for children aged 6 to 12 years.¹² This series of 20 allergens was developed based on a literature review of pediatric patch test results and case reports as well as a database review. The authors proposed additional allergens to be considered based on patient history.¹²

More recently, a 2017 American Contact Dermatitis Society physician work group proposed the Pediatric Baseline Patch Test Series. This series of 38 allergens for children aged 6 to 18 years was developed based on expert consensus.⁸ Studies to determine the efficacy of this series have yet to be conducted, but it may have high sensitivity in detecting relevant allergens in children as demonstrated by a theoretical detection rate of 84%.¹⁴

There are 2 recommended patch test series for allergic diaper dermatitis.¹⁵ The first series focuses on 23 potential allergens found in wet wipes and topical diaper preparations. The second series contains 10 potential allergens found in diapers. These series contain common topical medications for children including corticosteroids, antimicrobials, and sensitizers specific to diapers such as rubbers and adhesives.¹⁵

Similar to adults, it may be difficult to designate one screening panel that can identify all relevant allergens in children; thus, it is always important to obtain a thorough exposure history and customize testing to suspected allergens and/or patient products based on history and clinical relevance.

Unique Pediatric Allergens

Hobbies
Sports gear such as shin guards and splints often contain allergens such as formaldehyde resin, thiuram mix, and dialkyl thioureas.¹⁶ Perioral dermatitis may be caused by musical instrument mouthpieces containing nickel.⁶

Preservatives
Commonly reported causes of ACD in children include methylisothiazolinone (MI) and methylchloroisothiazolinone (MCI) found in wet wipes. A 2016 analysis of diaper wipes showed a low prevalence of MI (6.3%) and MCI (1.6%) in these products, which may reflect the industry’s awareness of these potential allergens and a subsequent change in the preservatives they utilize.¹⁷ However, the prevalence of MCI/MI contact allergy may be on the rise due to the popularity of homemade slime, which is made from common household products such as laundry detergent, dishwashing soap, and liquid glue. The Pediatric Baseline Patch Test Series captures most of the potential allergens in these homemade slime recipes and is recommended for use in pediatric patients suspected of having dermatitis secondary to playing with slime.^8,18

Toilet Seat Dermatitis
Toilet seat dermatitis presents as a pruritic dermatitis on the posterior upper thighs and buttocks. Although most cases of toilet seat dermatitis are irritant rather than allergic, potential allergens include plastics, fragrances, and components of cleaning products. Thus, physicians should maintain a high index of suspicion for ACD to toilet seats.¹⁹

Fragrance and Natural Ingredients
A 2018 study evaluating personal care products marketed specifically for infants and children found that 55% of products (294/533) contained at least 1 common allergen, with fragrance being the most common (48% [255/533]). Other common allergens include betaines (18%), propylene glycol (9%), lanolin (6%), and MCI/MI (3%).²⁰ Caregivers should be advised against the myth that natural products are safer and less allergenic and should be provided with resources such as the Contact Allergen Management Program (CAMP) database (https://www.contactderm.org/resources/acds-camp) for safe alternative personal care products.

Metal Allergens
Nickel, the American Contact Dermatitis Society 2008 Allergen of the Year, is another common allergen that affects children. Nickel allergy, commonly thought to affect the ears due to jewelry and ear piercing, may actually be found in a wide range of daily items such as braces, eyeglasses, keys, zippers, school chairs, electronics, toys, and even food.^3,6,21,22 With increased use of electronics in children of all ages, nickel found in mobile phones and other devices may be of particular concern. Caregivers can use a case or cover for metallic-appearing electronics.

Final Interpretation

Pediatric ACD is common. With limited surface area for patch testing in children, we recommend customized panels based on patient history and exposure. It is important for clinicians to recognize the unique causes of ACD in children and develop age-appropriate management plans.

The pediatric population has a unique product exposure profile due to the many care products specifically marketed for use in children. In fact, the prevalence of allergic contact dermatitis (ACD) in children may be as high as 24.5% in the United States.¹ In patch tested children, relevant positive reaction rates of 56.7% and 48% have been reported by the North American Contact Dermatitis Group and the Pediatric Contact Dermatitis Registry, respectively.^2,3 In this article, we provide an overview of current trends in pediatric patch testing as well as specific considerations in this patient population.

Patch Test Reactions in Children

Several publications have documented pediatric patch test reactions. The North American Contact Dermatitis Group reported patch test results in 883 children from the United States and Canada (2005-2012).² The most common reactions were nickel (28.1%), cobalt (12.3%), neomycin (7.1%), balsam of Peru (5.7%), lanolin (5.5%), and fragrance mix I (5.2%). When compared to adults, children were more likely to have relevant positive patch tests to nickel, cobalt, and compositae mix.² In comparison, data from the Pediatric Contact Dermatitis Registry showed that the most common reactions in 1142 children in the United States (2015-2016) were nickel (22%), fragrance mix I (11%), cobalt (9.1%), balsam of Peru (8.4%), neomycin (7.2%), and propylene glycol (6.8%).³

Allergen sensitivities may vary based on geographic region. In Spain, children showed the highest sensitivities to thiomersal (10.2%), cobalt (9.1%), colophony (9.1%), paraphenylenediamine (8.3%), mercury (7.9%), potassium dichromate (7.9%), and nickel (6.4%).⁴

Pediatric Patch Testing Pearls

History of Product Use
From diapers to drama club, pediatric exposures and sources of ACD are not the same as those seen in adults. Because obtaining a medical history from a toddler can be exasperating, the patient’s caregivers should be asked about potential exposures, ranging from personal care products and diapers to school activities, hobbies, and sports.^5,6 It is important to keep in mind that the patient’s primary caregiver may not be the only individual who applies products to the child.⁷

Application of Allergens
Children are not merely small adults, but they usually do have smaller backs than adult patients. This reduced surface area means that the patch tester must carefully select the allergens to be patch tested. For reference, the back of a typical 6-year-old child can fit 40 to 60 allergens during patch testing.⁸

Patch Test Chambers
In children, the use of plastic patch test chambers may be preferred over aluminum chambers. Children with persistent pruritic subcutaneous nodules induced by aluminum-based vaccines also may have delayed-type sensitivity reactions to aluminum.⁹ These patients could react to the aluminum present in some patch test chambers, making interpretation of the results difficult. The authors (A.R.A. and M.R.) typically use plastic chambers in the pediatric population.

Managing Expectations
As with other procedures in the pediatric population, patch testing can elicit emotions of fear, anxiety, and distrust. Video distraction and/or role-playing games may help capture the attention of children and can be particularly helpful during patch application. Children may be apprehensive about the term allergy testing if they are familiar with the term needle testing from previous allergies.⁵

Securing Patches
Young children can be quite active, posing another challenge for keeping patches in place. We recommend using extra tape to secure the patches in place on a child’s back. In addition, a large transparent film dressing (ie, 12×8 in) can be used if quick application is needed. For extra precaution, the use of a tight T-shirt or favorite onesie during the patch test process may be helpful, making it more difficult for little fingers to remove tape edges.

Duration of Patch Testing
Some authors have proposed application of patch tests for 24 hours in pediatric patients, as compared to 48 hours in adults.¹⁰ This recommendation is based on a theory that the reduced application period will decrease the risk for irritant reactions in pediatric patients.

Pediatric Patch Test Screening Series

A summary of the published screening series for patch testing in the pediatric population is provided (Table).

The T.R.U.E. Test (SmartPractice) is approved by the US Food and Drug Administration for use in patients 6 years and older¹¹; however, it may not adequately represent allergen exposures in the pediatric population. Brankov and Jacob¹⁴ found that 10 (40%) of their proposed top 25 pediatric allergens were not detected using the T.R.U.E. Test.

In 2014, the North American Pediatric Patch Test Series was proposed as a basic screening panel for children aged 6 to 12 years.¹² This series of 20 allergens was developed based on a literature review of pediatric patch test results and case reports as well as a database review. The authors proposed additional allergens to be considered based on patient history.¹²

More recently, a 2017 American Contact Dermatitis Society physician work group proposed the Pediatric Baseline Patch Test Series. This series of 38 allergens for children aged 6 to 18 years was developed based on expert consensus.⁸ Studies to determine the efficacy of this series have yet to be conducted, but it may have high sensitivity in detecting relevant allergens in children as demonstrated by a theoretical detection rate of 84%.¹⁴

There are 2 recommended patch test series for allergic diaper dermatitis.¹⁵ The first series focuses on 23 potential allergens found in wet wipes and topical diaper preparations. The second series contains 10 potential allergens found in diapers. These series contain common topical medications for children including corticosteroids, antimicrobials, and sensitizers specific to diapers such as rubbers and adhesives.¹⁵

Similar to adults, it may be difficult to designate one screening panel that can identify all relevant allergens in children; thus, it is always important to obtain a thorough exposure history and customize testing to suspected allergens and/or patient products based on history and clinical relevance.

Unique Pediatric Allergens

Hobbies
Sports gear such as shin guards and splints often contain allergens such as formaldehyde resin, thiuram mix, and dialkyl thioureas.¹⁶ Perioral dermatitis may be caused by musical instrument mouthpieces containing nickel.⁶

Preservatives
Commonly reported causes of ACD in children include methylisothiazolinone (MI) and methylchloroisothiazolinone (MCI) found in wet wipes. A 2016 analysis of diaper wipes showed a low prevalence of MI (6.3%) and MCI (1.6%) in these products, which may reflect the industry’s awareness of these potential allergens and a subsequent change in the preservatives they utilize.¹⁷ However, the prevalence of MCI/MI contact allergy may be on the rise due to the popularity of homemade slime, which is made from common household products such as laundry detergent, dishwashing soap, and liquid glue. The Pediatric Baseline Patch Test Series captures most of the potential allergens in these homemade slime recipes and is recommended for use in pediatric patients suspected of having dermatitis secondary to playing with slime.^8,18

Toilet Seat Dermatitis
Toilet seat dermatitis presents as a pruritic dermatitis on the posterior upper thighs and buttocks. Although most cases of toilet seat dermatitis are irritant rather than allergic, potential allergens include plastics, fragrances, and components of cleaning products. Thus, physicians should maintain a high index of suspicion for ACD to toilet seats.¹⁹

Fragrance and Natural Ingredients
A 2018 study evaluating personal care products marketed specifically for infants and children found that 55% of products (294/533) contained at least 1 common allergen, with fragrance being the most common (48% [255/533]). Other common allergens include betaines (18%), propylene glycol (9%), lanolin (6%), and MCI/MI (3%).²⁰ Caregivers should be advised against the myth that natural products are safer and less allergenic and should be provided with resources such as the Contact Allergen Management Program (CAMP) database (https://www.contactderm.org/resources/acds-camp) for safe alternative personal care products.

Metal Allergens
Nickel, the American Contact Dermatitis Society 2008 Allergen of the Year, is another common allergen that affects children. Nickel allergy, commonly thought to affect the ears due to jewelry and ear piercing, may actually be found in a wide range of daily items such as braces, eyeglasses, keys, zippers, school chairs, electronics, toys, and even food.^3,6,21,22 With increased use of electronics in children of all ages, nickel found in mobile phones and other devices may be of particular concern. Caregivers can use a case or cover for metallic-appearing electronics.

Final Interpretation

Pediatric ACD is common. With limited surface area for patch testing in children, we recommend customized panels based on patient history and exposure. It is important for clinicians to recognize the unique causes of ACD in children and develop age-appropriate management plans.

BARCELONA – Disturbed HDL cholesterol metabolism is one of the earliest features that may predispose individuals to the development of type 2 diabetes, according to data from a genetics and metabolomics study conducted in the United Kingdom.

Sara Freeman/MDedge News

Changes in HDL cholesterol metabolism were seen in children as young as 8 years, decades before the clinical onset of disease, Joshua Bell, PhD, a research fellow at the University of Bristol (England), reported at the annual meeting of the European Association for the Study of Diabetes.

“We know that type 2 diabetes certainly doesn’t develop overnight,” Dr. Bell said. Indeed, data exist showing that there are changes in glucose metabolism several years before a formal diagnosis may be made in adults. “What we don’t know is what the very earliest features of diabetes look like,” he added.

“The main assumption is that type 2 diabetes is a metabolic disease, and so disease features are visible in systemic metabolism,” explained Dr. Bell. What was not clear, however, was that if any metabolic features – seen mainly in observational studies and in adults – were caused by the disease itself or perhaps were independent causes of type 2 diabetes.To investigate, Dr. Bell and associates performed a study linking genetic liability with metabolomic data collected at four time points from 4,761 offspring from participants in the Avon Longitudinal Study of Parents and Children cohort, which is also known as the Children of the 90s cohort. More than 200 metabolic traits were considered, and a genetic risk score comprising more than 162 single nucleotide polymorphisms previously linked to adult type 2 diabetes was used.

The metabolomic traits considered included lipoprotein subclass-specific cholesterol and triglyceride content, amino and fatty acids, and inflammatory glycoprotein acetyls, which had been measured in childhood at the age of 8 years, in adolescence at 16 years, in young adulthood at 18 years, and in adulthood at 25 years.

Early metabolic features of type 2 diabetes liability were grouped together and one feature that stood out was the sizes of lipid particles. In particular, it was the size of HDL cholesterol particle subtypes in children at the age of 8 years. Before other types of changes in lipid particles were being seen, there were reductions in the lipid content of HDL cholesterol particle subtypes, notably those that were very large.

By age 16 years, strong associations remained with lower lipids in HDL cholesterol particle subtypes and type 2 diabetes liability, which became stronger with preglycemic traits, such as citrate, and with glycoprotein acetyls. By age 18 years, elevations were seen in branched amino acids, and by age 25, association had strengthened for the lipid content of very low–density lipoprotein cholesterol.

“Linking genetic liability to adult disease with traits measured much earlier in life can tell you something about how the disease activity unfolds over a lifetime,” Dr. Bell said, adding that the feature that was “most consistently tracked” could be evaluated and could help reveal whether or not an individual might go on to develop type 2 diabetes.

In a press release issued by the EASD, Dr. Bell observed: “It’s remarkable that we can see signs of adult diabetes in the blood from such a young age. Knowing what early features of type 2 diabetes look like, could help us to intervene much earlier to halt progression to full-blown diabetes and its complications.”

The study was funded by Diabetes U.K., Cancer Research U.K., the Elizabeth Blackwell Institute for Health Research, the Wellcome Trust, the Medical Research Council, and the University of Bristol. Dr. Bell said he had no conflicts of interest to declare.

SOURCE: Bell J et al. bioRxiv. 2019 Sep 17. doi: 10.1101/767756.
 

BARCELONA – Disturbed HDL cholesterol metabolism is one of the earliest features that may predispose individuals to the development of type 2 diabetes, according to data from a genetics and metabolomics study conducted in the United Kingdom.

Sara Freeman/MDedge News

Changes in HDL cholesterol metabolism were seen in children as young as 8 years, decades before the clinical onset of disease, Joshua Bell, PhD, a research fellow at the University of Bristol (England), reported at the annual meeting of the European Association for the Study of Diabetes.

“We know that type 2 diabetes certainly doesn’t develop overnight,” Dr. Bell said. Indeed, data exist showing that there are changes in glucose metabolism several years before a formal diagnosis may be made in adults. “What we don’t know is what the very earliest features of diabetes look like,” he added.

“The main assumption is that type 2 diabetes is a metabolic disease, and so disease features are visible in systemic metabolism,” explained Dr. Bell. What was not clear, however, was that if any metabolic features – seen mainly in observational studies and in adults – were caused by the disease itself or perhaps were independent causes of type 2 diabetes.To investigate, Dr. Bell and associates performed a study linking genetic liability with metabolomic data collected at four time points from 4,761 offspring from participants in the Avon Longitudinal Study of Parents and Children cohort, which is also known as the Children of the 90s cohort. More than 200 metabolic traits were considered, and a genetic risk score comprising more than 162 single nucleotide polymorphisms previously linked to adult type 2 diabetes was used.

The metabolomic traits considered included lipoprotein subclass-specific cholesterol and triglyceride content, amino and fatty acids, and inflammatory glycoprotein acetyls, which had been measured in childhood at the age of 8 years, in adolescence at 16 years, in young adulthood at 18 years, and in adulthood at 25 years.

Early metabolic features of type 2 diabetes liability were grouped together and one feature that stood out was the sizes of lipid particles. In particular, it was the size of HDL cholesterol particle subtypes in children at the age of 8 years. Before other types of changes in lipid particles were being seen, there were reductions in the lipid content of HDL cholesterol particle subtypes, notably those that were very large.

By age 16 years, strong associations remained with lower lipids in HDL cholesterol particle subtypes and type 2 diabetes liability, which became stronger with preglycemic traits, such as citrate, and with glycoprotein acetyls. By age 18 years, elevations were seen in branched amino acids, and by age 25, association had strengthened for the lipid content of very low–density lipoprotein cholesterol.

“Linking genetic liability to adult disease with traits measured much earlier in life can tell you something about how the disease activity unfolds over a lifetime,” Dr. Bell said, adding that the feature that was “most consistently tracked” could be evaluated and could help reveal whether or not an individual might go on to develop type 2 diabetes.

In a press release issued by the EASD, Dr. Bell observed: “It’s remarkable that we can see signs of adult diabetes in the blood from such a young age. Knowing what early features of type 2 diabetes look like, could help us to intervene much earlier to halt progression to full-blown diabetes and its complications.”

The study was funded by Diabetes U.K., Cancer Research U.K., the Elizabeth Blackwell Institute for Health Research, the Wellcome Trust, the Medical Research Council, and the University of Bristol. Dr. Bell said he had no conflicts of interest to declare.

SOURCE: Bell J et al. bioRxiv. 2019 Sep 17. doi: 10.1101/767756.
 

BARCELONA – Disturbed HDL cholesterol metabolism is one of the earliest features that may predispose individuals to the development of type 2 diabetes, according to data from a genetics and metabolomics study conducted in the United Kingdom.

Sara Freeman/MDedge News

Changes in HDL cholesterol metabolism were seen in children as young as 8 years, decades before the clinical onset of disease, Joshua Bell, PhD, a research fellow at the University of Bristol (England), reported at the annual meeting of the European Association for the Study of Diabetes.

“We know that type 2 diabetes certainly doesn’t develop overnight,” Dr. Bell said. Indeed, data exist showing that there are changes in glucose metabolism several years before a formal diagnosis may be made in adults. “What we don’t know is what the very earliest features of diabetes look like,” he added.

“The main assumption is that type 2 diabetes is a metabolic disease, and so disease features are visible in systemic metabolism,” explained Dr. Bell. What was not clear, however, was that if any metabolic features – seen mainly in observational studies and in adults – were caused by the disease itself or perhaps were independent causes of type 2 diabetes.To investigate, Dr. Bell and associates performed a study linking genetic liability with metabolomic data collected at four time points from 4,761 offspring from participants in the Avon Longitudinal Study of Parents and Children cohort, which is also known as the Children of the 90s cohort. More than 200 metabolic traits were considered, and a genetic risk score comprising more than 162 single nucleotide polymorphisms previously linked to adult type 2 diabetes was used.

The metabolomic traits considered included lipoprotein subclass-specific cholesterol and triglyceride content, amino and fatty acids, and inflammatory glycoprotein acetyls, which had been measured in childhood at the age of 8 years, in adolescence at 16 years, in young adulthood at 18 years, and in adulthood at 25 years.

Early metabolic features of type 2 diabetes liability were grouped together and one feature that stood out was the sizes of lipid particles. In particular, it was the size of HDL cholesterol particle subtypes in children at the age of 8 years. Before other types of changes in lipid particles were being seen, there were reductions in the lipid content of HDL cholesterol particle subtypes, notably those that were very large.

By age 16 years, strong associations remained with lower lipids in HDL cholesterol particle subtypes and type 2 diabetes liability, which became stronger with preglycemic traits, such as citrate, and with glycoprotein acetyls. By age 18 years, elevations were seen in branched amino acids, and by age 25, association had strengthened for the lipid content of very low–density lipoprotein cholesterol.

“Linking genetic liability to adult disease with traits measured much earlier in life can tell you something about how the disease activity unfolds over a lifetime,” Dr. Bell said, adding that the feature that was “most consistently tracked” could be evaluated and could help reveal whether or not an individual might go on to develop type 2 diabetes.

In a press release issued by the EASD, Dr. Bell observed: “It’s remarkable that we can see signs of adult diabetes in the blood from such a young age. Knowing what early features of type 2 diabetes look like, could help us to intervene much earlier to halt progression to full-blown diabetes and its complications.”

The study was funded by Diabetes U.K., Cancer Research U.K., the Elizabeth Blackwell Institute for Health Research, the Wellcome Trust, the Medical Research Council, and the University of Bristol. Dr. Bell said he had no conflicts of interest to declare.

SOURCE: Bell J et al. bioRxiv. 2019 Sep 17. doi: 10.1101/767756.
 

WASHINGTON – Early diagnosis and intervention for genetic diseases using the latest carrier screening can allow families to be prepared and informed prior to pregnancy, said Aishwarya Arjunan, MS, MPH, a clinical product specialist for carrier screening at Myriad Women’s Health, part of a diagnostic testing company based in Salt Lake City, Utah.

Piolinfax/Wikimedia Commons/GNU Free Documentation License

“Rare diseases are responsible for 35% of deaths in the first year of life,” she said in a panel discussion at the Rare Diseases and Orphan Products Breakthrough Summit sponsored by the National Organization for Rare Disorders.

Most patients with rare diseases go through a “diagnostic odyssey” lasting an average of 8 years before they receive an accurate diagnosis, she said. During this time, data suggest that they have likely been misdiagnosed three times and have seen more than 10 specialists, she added.

Barriers to genetic screening include limited access to genetics professionals, lack of patient and provider education about screening, issues of insurance coverage and reimbursement, coding challenges, and misperceptions about the perceived impact of screening, noted Jodie Vento, manager of the Center for Rare Disease Therapy at the Children’s Hospital of Pittsburgh.

The genetic carrier screening options, often referred to as panethnic expanded carrier screening, represents a change from previous screening protocols based on ethnicity, said Ms. Arjunan. However, guidelines for screening based on ethnicity “misses a significant percentage of pregnancies affected by serious conditions and widens the health disparity gap,” she said.

By contrast, expanded carrier screening allows for standardization of care that gives couples and families information to make decisions and preparations.

Current genetic testing strategies include single gene testing, in which a single gene of interest is tested; multigene panel testing, in which a subset of clinically important genes are tested; whole-exome sequencing, in which the DNA responsible for coding proteins is tested; and whole-genome sequencing, in which the entire human genome is tested for genetic disorders.

Improving access to genetic testing involves a combination of provider education, changes in payer policies, action by advocacy groups, and adjustment of societal guidelines, said Ms. Arjunan. However, the advantages of expanded carrier screening are many and include guiding patients to expert care early and setting up plans for long-term care and follow-up, she noted. In addition, early identification through screening can help patients reduce or eliminate the diagnostic odyssey and connect with advocacy and community groups for support, she concluded.

The presenters had no financial conflicts to disclose.

WASHINGTON – Early diagnosis and intervention for genetic diseases using the latest carrier screening can allow families to be prepared and informed prior to pregnancy, said Aishwarya Arjunan, MS, MPH, a clinical product specialist for carrier screening at Myriad Women’s Health, part of a diagnostic testing company based in Salt Lake City, Utah.

Piolinfax/Wikimedia Commons/GNU Free Documentation License

“Rare diseases are responsible for 35% of deaths in the first year of life,” she said in a panel discussion at the Rare Diseases and Orphan Products Breakthrough Summit sponsored by the National Organization for Rare Disorders.

Most patients with rare diseases go through a “diagnostic odyssey” lasting an average of 8 years before they receive an accurate diagnosis, she said. During this time, data suggest that they have likely been misdiagnosed three times and have seen more than 10 specialists, she added.

Barriers to genetic screening include limited access to genetics professionals, lack of patient and provider education about screening, issues of insurance coverage and reimbursement, coding challenges, and misperceptions about the perceived impact of screening, noted Jodie Vento, manager of the Center for Rare Disease Therapy at the Children’s Hospital of Pittsburgh.

The genetic carrier screening options, often referred to as panethnic expanded carrier screening, represents a change from previous screening protocols based on ethnicity, said Ms. Arjunan. However, guidelines for screening based on ethnicity “misses a significant percentage of pregnancies affected by serious conditions and widens the health disparity gap,” she said.

By contrast, expanded carrier screening allows for standardization of care that gives couples and families information to make decisions and preparations.

Current genetic testing strategies include single gene testing, in which a single gene of interest is tested; multigene panel testing, in which a subset of clinically important genes are tested; whole-exome sequencing, in which the DNA responsible for coding proteins is tested; and whole-genome sequencing, in which the entire human genome is tested for genetic disorders.

Improving access to genetic testing involves a combination of provider education, changes in payer policies, action by advocacy groups, and adjustment of societal guidelines, said Ms. Arjunan. However, the advantages of expanded carrier screening are many and include guiding patients to expert care early and setting up plans for long-term care and follow-up, she noted. In addition, early identification through screening can help patients reduce or eliminate the diagnostic odyssey and connect with advocacy and community groups for support, she concluded.

The presenters had no financial conflicts to disclose.

WASHINGTON – Early diagnosis and intervention for genetic diseases using the latest carrier screening can allow families to be prepared and informed prior to pregnancy, said Aishwarya Arjunan, MS, MPH, a clinical product specialist for carrier screening at Myriad Women’s Health, part of a diagnostic testing company based in Salt Lake City, Utah.

Piolinfax/Wikimedia Commons/GNU Free Documentation License

“Rare diseases are responsible for 35% of deaths in the first year of life,” she said in a panel discussion at the Rare Diseases and Orphan Products Breakthrough Summit sponsored by the National Organization for Rare Disorders.

Most patients with rare diseases go through a “diagnostic odyssey” lasting an average of 8 years before they receive an accurate diagnosis, she said. During this time, data suggest that they have likely been misdiagnosed three times and have seen more than 10 specialists, she added.

Barriers to genetic screening include limited access to genetics professionals, lack of patient and provider education about screening, issues of insurance coverage and reimbursement, coding challenges, and misperceptions about the perceived impact of screening, noted Jodie Vento, manager of the Center for Rare Disease Therapy at the Children’s Hospital of Pittsburgh.

The genetic carrier screening options, often referred to as panethnic expanded carrier screening, represents a change from previous screening protocols based on ethnicity, said Ms. Arjunan. However, guidelines for screening based on ethnicity “misses a significant percentage of pregnancies affected by serious conditions and widens the health disparity gap,” she said.

By contrast, expanded carrier screening allows for standardization of care that gives couples and families information to make decisions and preparations.

Current genetic testing strategies include single gene testing, in which a single gene of interest is tested; multigene panel testing, in which a subset of clinically important genes are tested; whole-exome sequencing, in which the DNA responsible for coding proteins is tested; and whole-genome sequencing, in which the entire human genome is tested for genetic disorders.

Improving access to genetic testing involves a combination of provider education, changes in payer policies, action by advocacy groups, and adjustment of societal guidelines, said Ms. Arjunan. However, the advantages of expanded carrier screening are many and include guiding patients to expert care early and setting up plans for long-term care and follow-up, she noted. In addition, early identification through screening can help patients reduce or eliminate the diagnostic odyssey and connect with advocacy and community groups for support, she concluded.

The presenters had no financial conflicts to disclose.

A new study has uncovered how the measles virus (MeV) can induce immunosuppression by delaying the reconstitution of B cells.

CDC/ Cynthia S. Goldsmith; William Bellini, Ph.D.

“Our findings provide a biological explanation for the observed increase in childhood mortality and secondary infections several years after an episode of measles,” said Velislava N. Petrova, PhD, of the Wellcome Sanger Institute in Cambridge, England, and coauthors. The study was published in Science Immunology.

To determine if B-cell impairment can lead to measles-associated immunosuppression, the researchers investigated genetic changes in 26 unvaccinated children from the Netherlands who previously had measles. Their antibody genes were sequenced before any symptoms of measles developed and roughly 40 days after rash. Two control groups also were sequenced accordingly: vaccinated adults and three unvaccinated children from the same community who were not infected with measles.

Naive B cells from individuals in the vaccinated and uninfected control groups showed high correlation of immunoglobulin heavy chain (IGHV-J) gene frequencies across time periods (R² = 0.96 and 0.92, respectively) but no significant differences in gene expression (P greater than .05). At the same time, although B cell frequencies in measles patients recovered to levels before infection, they had significant changes in IGHV-J gene frequencies (P = .01) and decreased correlation in gene expression (R² = 0.78).

In addition, individuals in the control groups had “a stable genetic composition of B memory cells” but no significant changes in the third complementarity-determining region (CDR3) lengths or mutational frequency of IGHV genes (P greater than .05). B memory cells in measles patients, however, showed increases in mutational frequency (P = .0008) and a reduction in CDR3 length (P = .017) of IGHV genes, Dr. Petrova and associates said.

Finally, the researchers confirmed a hypothesis about the depletion of B memory cell clones during measles and a repopulation of new cells with less clonal expansion. The frequency of individual IGHV-J gene combinations before infection was correlated with a reduction after infection, “with the most frequent combinations undergoing the most marked depletion” and the result being an increase in genetic diversity.

To further test their findings, the researchers vaccinated two groups of four ferrets with live-attenuated influenza vaccine (LAIV) and at 4 weeks infected one of the groups with canine distemper virus (CDV), a surrogate for MeV. At 14 weeks after vaccination, the uninfected group maintained high levels of influenza-specific neutralizing antibodies while the infected group saw impaired B cells and a subsequent reduction in neutralizing antibodies.
 

Understanding the impact of measles on the immune system

“How measles infection has such a long-lasting deleterious effect on the immune system while allowing robust immunity against itself has been a burning immunological question,” Duane R. Wesemann, MD, PhD, of Brigham and Women’s Hospital in Boston, said in an accompanying editorial. The research from Petrova et al. begins to answer that question.

Among the observations he found most interesting was how “post-measles memory cells were more diverse than the pre-measles memory pool,” despite expectations that measles immunity would be dominant. He speculated that the void in memory cells is filled by a set of clones binding to unidentified or nonnative antigens, which may bring polyclonal diversity into B memory cells.

More research is needed to determine just what these findings mean, including looking beyond memory cell depletion and focusing on the impact of immature immunoglobulin repertoires in naive cells. But his broad takeaway is that measles remains both a public health concern and an opportunity to understand how the human body counters disease.

“The unique relationship measles has with the human immune system,” he said, “can illuminate aspects of its inner workings.”

The study was funded by grants to the investigators the Indonesian Endowment Fund for Education, the Wellcome Trust, the German Centre for Infection Research, the Collaborative Research Centre of the German Research Foundation, the German Ministry of Health, and the Royal Society. The authors declared no conflicts of interest. Dr. Wesemann reported receiving support from National Institutes of Health grants and an award from the Burroughs Wellcome Fund; he also reports being a consultant for OpenBiome.

SOURCE: Petrova VN et al. Sci Immunol. 2019 Nov 1. doi: 10.1126/sciimmunol.aay6125; Wesemann DR. Sci Immunol. 2019 Nov 1. doi: 10.1126/sciimmunol.aaz4195.

A new study has uncovered how the measles virus (MeV) can induce immunosuppression by delaying the reconstitution of B cells.

CDC/ Cynthia S. Goldsmith; William Bellini, Ph.D.

“Our findings provide a biological explanation for the observed increase in childhood mortality and secondary infections several years after an episode of measles,” said Velislava N. Petrova, PhD, of the Wellcome Sanger Institute in Cambridge, England, and coauthors. The study was published in Science Immunology.

To determine if B-cell impairment can lead to measles-associated immunosuppression, the researchers investigated genetic changes in 26 unvaccinated children from the Netherlands who previously had measles. Their antibody genes were sequenced before any symptoms of measles developed and roughly 40 days after rash. Two control groups also were sequenced accordingly: vaccinated adults and three unvaccinated children from the same community who were not infected with measles.

Naive B cells from individuals in the vaccinated and uninfected control groups showed high correlation of immunoglobulin heavy chain (IGHV-J) gene frequencies across time periods (R² = 0.96 and 0.92, respectively) but no significant differences in gene expression (P greater than .05). At the same time, although B cell frequencies in measles patients recovered to levels before infection, they had significant changes in IGHV-J gene frequencies (P = .01) and decreased correlation in gene expression (R² = 0.78).

In addition, individuals in the control groups had “a stable genetic composition of B memory cells” but no significant changes in the third complementarity-determining region (CDR3) lengths or mutational frequency of IGHV genes (P greater than .05). B memory cells in measles patients, however, showed increases in mutational frequency (P = .0008) and a reduction in CDR3 length (P = .017) of IGHV genes, Dr. Petrova and associates said.

Finally, the researchers confirmed a hypothesis about the depletion of B memory cell clones during measles and a repopulation of new cells with less clonal expansion. The frequency of individual IGHV-J gene combinations before infection was correlated with a reduction after infection, “with the most frequent combinations undergoing the most marked depletion” and the result being an increase in genetic diversity.

To further test their findings, the researchers vaccinated two groups of four ferrets with live-attenuated influenza vaccine (LAIV) and at 4 weeks infected one of the groups with canine distemper virus (CDV), a surrogate for MeV. At 14 weeks after vaccination, the uninfected group maintained high levels of influenza-specific neutralizing antibodies while the infected group saw impaired B cells and a subsequent reduction in neutralizing antibodies.
 

Understanding the impact of measles on the immune system

“How measles infection has such a long-lasting deleterious effect on the immune system while allowing robust immunity against itself has been a burning immunological question,” Duane R. Wesemann, MD, PhD, of Brigham and Women’s Hospital in Boston, said in an accompanying editorial. The research from Petrova et al. begins to answer that question.

Among the observations he found most interesting was how “post-measles memory cells were more diverse than the pre-measles memory pool,” despite expectations that measles immunity would be dominant. He speculated that the void in memory cells is filled by a set of clones binding to unidentified or nonnative antigens, which may bring polyclonal diversity into B memory cells.

More research is needed to determine just what these findings mean, including looking beyond memory cell depletion and focusing on the impact of immature immunoglobulin repertoires in naive cells. But his broad takeaway is that measles remains both a public health concern and an opportunity to understand how the human body counters disease.

“The unique relationship measles has with the human immune system,” he said, “can illuminate aspects of its inner workings.”

The study was funded by grants to the investigators the Indonesian Endowment Fund for Education, the Wellcome Trust, the German Centre for Infection Research, the Collaborative Research Centre of the German Research Foundation, the German Ministry of Health, and the Royal Society. The authors declared no conflicts of interest. Dr. Wesemann reported receiving support from National Institutes of Health grants and an award from the Burroughs Wellcome Fund; he also reports being a consultant for OpenBiome.

SOURCE: Petrova VN et al. Sci Immunol. 2019 Nov 1. doi: 10.1126/sciimmunol.aay6125; Wesemann DR. Sci Immunol. 2019 Nov 1. doi: 10.1126/sciimmunol.aaz4195.

A new study has uncovered how the measles virus (MeV) can induce immunosuppression by delaying the reconstitution of B cells.

CDC/ Cynthia S. Goldsmith; William Bellini, Ph.D.

“Our findings provide a biological explanation for the observed increase in childhood mortality and secondary infections several years after an episode of measles,” said Velislava N. Petrova, PhD, of the Wellcome Sanger Institute in Cambridge, England, and coauthors. The study was published in Science Immunology.

To determine if B-cell impairment can lead to measles-associated immunosuppression, the researchers investigated genetic changes in 26 unvaccinated children from the Netherlands who previously had measles. Their antibody genes were sequenced before any symptoms of measles developed and roughly 40 days after rash. Two control groups also were sequenced accordingly: vaccinated adults and three unvaccinated children from the same community who were not infected with measles.

Naive B cells from individuals in the vaccinated and uninfected control groups showed high correlation of immunoglobulin heavy chain (IGHV-J) gene frequencies across time periods (R² = 0.96 and 0.92, respectively) but no significant differences in gene expression (P greater than .05). At the same time, although B cell frequencies in measles patients recovered to levels before infection, they had significant changes in IGHV-J gene frequencies (P = .01) and decreased correlation in gene expression (R² = 0.78).

In addition, individuals in the control groups had “a stable genetic composition of B memory cells” but no significant changes in the third complementarity-determining region (CDR3) lengths or mutational frequency of IGHV genes (P greater than .05). B memory cells in measles patients, however, showed increases in mutational frequency (P = .0008) and a reduction in CDR3 length (P = .017) of IGHV genes, Dr. Petrova and associates said.

Finally, the researchers confirmed a hypothesis about the depletion of B memory cell clones during measles and a repopulation of new cells with less clonal expansion. The frequency of individual IGHV-J gene combinations before infection was correlated with a reduction after infection, “with the most frequent combinations undergoing the most marked depletion” and the result being an increase in genetic diversity.

To further test their findings, the researchers vaccinated two groups of four ferrets with live-attenuated influenza vaccine (LAIV) and at 4 weeks infected one of the groups with canine distemper virus (CDV), a surrogate for MeV. At 14 weeks after vaccination, the uninfected group maintained high levels of influenza-specific neutralizing antibodies while the infected group saw impaired B cells and a subsequent reduction in neutralizing antibodies.
 

Understanding the impact of measles on the immune system

“How measles infection has such a long-lasting deleterious effect on the immune system while allowing robust immunity against itself has been a burning immunological question,” Duane R. Wesemann, MD, PhD, of Brigham and Women’s Hospital in Boston, said in an accompanying editorial. The research from Petrova et al. begins to answer that question.

Among the observations he found most interesting was how “post-measles memory cells were more diverse than the pre-measles memory pool,” despite expectations that measles immunity would be dominant. He speculated that the void in memory cells is filled by a set of clones binding to unidentified or nonnative antigens, which may bring polyclonal diversity into B memory cells.

More research is needed to determine just what these findings mean, including looking beyond memory cell depletion and focusing on the impact of immature immunoglobulin repertoires in naive cells. But his broad takeaway is that measles remains both a public health concern and an opportunity to understand how the human body counters disease.

“The unique relationship measles has with the human immune system,” he said, “can illuminate aspects of its inner workings.”

The study was funded by grants to the investigators the Indonesian Endowment Fund for Education, the Wellcome Trust, the German Centre for Infection Research, the Collaborative Research Centre of the German Research Foundation, the German Ministry of Health, and the Royal Society. The authors declared no conflicts of interest. Dr. Wesemann reported receiving support from National Institutes of Health grants and an award from the Burroughs Wellcome Fund; he also reports being a consultant for OpenBiome.

SOURCE: Petrova VN et al. Sci Immunol. 2019 Nov 1. doi: 10.1126/sciimmunol.aay6125; Wesemann DR. Sci Immunol. 2019 Nov 1. doi: 10.1126/sciimmunol.aaz4195.