Both approaches resulted in function and pain improvement

A 2013 multicenter RCT evaluated 351 adults, 45 years and older, with a meniscal tear and mild to moderate osteoarthritis confirmed by imaging, for functional improvement by physical therapy alone compared with arthroscopic partial meniscectomy and physical therapy.¹

At the beginning of the study and 6 and 12 months after treatment, researchers assessed symptoms using the Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index physical-function score (0-100, with higher scores indicating more severe symptoms), the Knee Injury and Osteoarthritis Outcome Score (KOOS) for pain (0-100, with higher numbers correlating with less pain), and the 36-item Short Form Health Survey (SF-36) for physical activity (0-100, with higher scores indicating greater physical activity).

Modified intention to treat analysis showed no significant difference in function and pain improvement at 6 and 12 months between patients with meniscal injury who underwent arthroscopic repair and physical therapy and patients who underwent physical therapy alone (TABLE¹). A limitation of the study was the crossover of 30% of patients from the nonoperative group to the operative group.

No differences found in Tx outcomes for nontraumatic tears

A 2007 prospective RCT evaluated 90 adults ages 45 to 64 with nontraumatic meniscal tears confirmed by magnetic resonance imaging for improvement in knee pain and function with arthroscopic treatment and supervised exercise (AE) or supervised exercise (E) alone.² Knee pain and function were assessed before intervention, after 8 weeks, and after 6 months of treatment using 3 surveys: the KOOS, the Lysholm Knee Scoring Scale (LKSS; 0-100, with higher scores correlating with good knee function), and the Visual Analogue Scale (VAS) for knee pain (0-10, with 0 indicating no pain and 10 indicating maximum pain).

The KOOS revealed that at 8 weeks and 6 months both groups had significant improvement from the initial evaluation in all subscale scores. In the AE group, the 8-week pain score increased from a baseline of 56 to 89 (P<.001) and remained at 89 at 6 months (P<.001). For the E group, the 8-week pain score improved from a baseline of 62 to 86 (P<.001) and continued at 86 after 6 months (P<.001).

The LKSS score for both groups showed significant improvement from baseline at 8 weeks: 34% of the AE group and 42% of the E group scored higher than 91 (P<.001).

VAS scores showed a significant decrease in pain at 8 weeks for both the AE and E groups: beginning median value for both groups was 5.5 and decreased to 1.0 at 8 weeks and 6 months (P<.001).

The authors concluded that both groups improved significantly from initial evaluation regardless of treatment method and that no statistically significant difference existed between treatment results.

Both approaches resulted in function and pain improvement

A 2013 multicenter RCT evaluated 351 adults, 45 years and older, with a meniscal tear and mild to moderate osteoarthritis confirmed by imaging, for functional improvement by physical therapy alone compared with arthroscopic partial meniscectomy and physical therapy.¹

At the beginning of the study and 6 and 12 months after treatment, researchers assessed symptoms using the Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index physical-function score (0-100, with higher scores indicating more severe symptoms), the Knee Injury and Osteoarthritis Outcome Score (KOOS) for pain (0-100, with higher numbers correlating with less pain), and the 36-item Short Form Health Survey (SF-36) for physical activity (0-100, with higher scores indicating greater physical activity).

Modified intention to treat analysis showed no significant difference in function and pain improvement at 6 and 12 months between patients with meniscal injury who underwent arthroscopic repair and physical therapy and patients who underwent physical therapy alone (TABLE¹). A limitation of the study was the crossover of 30% of patients from the nonoperative group to the operative group.

No differences found in Tx outcomes for nontraumatic tears

A 2007 prospective RCT evaluated 90 adults ages 45 to 64 with nontraumatic meniscal tears confirmed by magnetic resonance imaging for improvement in knee pain and function with arthroscopic treatment and supervised exercise (AE) or supervised exercise (E) alone.² Knee pain and function were assessed before intervention, after 8 weeks, and after 6 months of treatment using 3 surveys: the KOOS, the Lysholm Knee Scoring Scale (LKSS; 0-100, with higher scores correlating with good knee function), and the Visual Analogue Scale (VAS) for knee pain (0-10, with 0 indicating no pain and 10 indicating maximum pain).

The KOOS revealed that at 8 weeks and 6 months both groups had significant improvement from the initial evaluation in all subscale scores. In the AE group, the 8-week pain score increased from a baseline of 56 to 89 (P<.001) and remained at 89 at 6 months (P<.001). For the E group, the 8-week pain score improved from a baseline of 62 to 86 (P<.001) and continued at 86 after 6 months (P<.001).

The LKSS score for both groups showed significant improvement from baseline at 8 weeks: 34% of the AE group and 42% of the E group scored higher than 91 (P<.001).

VAS scores showed a significant decrease in pain at 8 weeks for both the AE and E groups: beginning median value for both groups was 5.5 and decreased to 1.0 at 8 weeks and 6 months (P<.001).

The authors concluded that both groups improved significantly from initial evaluation regardless of treatment method and that no statistically significant difference existed between treatment results.

Both approaches resulted in function and pain improvement

A 2013 multicenter RCT evaluated 351 adults, 45 years and older, with a meniscal tear and mild to moderate osteoarthritis confirmed by imaging, for functional improvement by physical therapy alone compared with arthroscopic partial meniscectomy and physical therapy.¹

At the beginning of the study and 6 and 12 months after treatment, researchers assessed symptoms using the Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index physical-function score (0-100, with higher scores indicating more severe symptoms), the Knee Injury and Osteoarthritis Outcome Score (KOOS) for pain (0-100, with higher numbers correlating with less pain), and the 36-item Short Form Health Survey (SF-36) for physical activity (0-100, with higher scores indicating greater physical activity).

Modified intention to treat analysis showed no significant difference in function and pain improvement at 6 and 12 months between patients with meniscal injury who underwent arthroscopic repair and physical therapy and patients who underwent physical therapy alone (TABLE¹). A limitation of the study was the crossover of 30% of patients from the nonoperative group to the operative group.

No differences found in Tx outcomes for nontraumatic tears

A 2007 prospective RCT evaluated 90 adults ages 45 to 64 with nontraumatic meniscal tears confirmed by magnetic resonance imaging for improvement in knee pain and function with arthroscopic treatment and supervised exercise (AE) or supervised exercise (E) alone.² Knee pain and function were assessed before intervention, after 8 weeks, and after 6 months of treatment using 3 surveys: the KOOS, the Lysholm Knee Scoring Scale (LKSS; 0-100, with higher scores correlating with good knee function), and the Visual Analogue Scale (VAS) for knee pain (0-10, with 0 indicating no pain and 10 indicating maximum pain).

The KOOS revealed that at 8 weeks and 6 months both groups had significant improvement from the initial evaluation in all subscale scores. In the AE group, the 8-week pain score increased from a baseline of 56 to 89 (P<.001) and remained at 89 at 6 months (P<.001). For the E group, the 8-week pain score improved from a baseline of 62 to 86 (P<.001) and continued at 86 after 6 months (P<.001).

The LKSS score for both groups showed significant improvement from baseline at 8 weeks: 34% of the AE group and 42% of the E group scored higher than 91 (P<.001).

VAS scores showed a significant decrease in pain at 8 weeks for both the AE and E groups: beginning median value for both groups was 5.5 and decreased to 1.0 at 8 weeks and 6 months (P<.001).

The authors concluded that both groups improved significantly from initial evaluation regardless of treatment method and that no statistically significant difference existed between treatment results.

ANSWER
The correct answer is nevus sebaceous (choice “a”). This benign hamartomatous lesion is derived from local tissue and grows at the same rate.

It differs considerably from the other items in the differential, including aplasia cutis congenita (choice “b”). In this condition, a focal area of epidermis simply fails to develop, leaving a permanent hairless scar that contrasts sharply with the raised, mammillated plaque of nevus sebaceous.

Epidermal nevus (choice “c”) is usually a collection of tan to brown superficial nevoid papules that can be linear, agminated, or plaque-like. These lesions lack the color and mammillated surface of those seen in nevus sebaceous.

Neonatal lupus (choice “d”) can present at birth with hairless, cicatricial inflamed lesions. However, these tend to resolve quickly, often leaving focal scarring alopecia but no plaque formation.

DISCUSSION
Nevus sebaceous (NS), first described by Jadassohn in 1895, has long been recognized as an unusual but by no means rare congenital lesion. Occurring equally in both sexes and comprising ­sebaceous glands in a nevoid morphologic context, NS is considered a variant of sebaceous nevi and verrucous epidermal nevi in some circles. All three are derived from overgrowth of local, normal tissues that typically grow at the same rate as surrounding structures.

The vast majority of NS lesions are found in the scalp, although they can also develop on the ear or neck and, rarely, elsewhere on the body. This patient’s plaque—with its uniform surface; tiny, smooth, shiny papules; and (perhaps most important) total lack of hair—is typical. Other classic features are congenital onset and permanent nature, which distinguish them from the rest of the differential.

Focal malignant transformation of NS lesions has been reported—in fact, this author has seen two such cases in 30 years. Both were small basal cell carcinomas, although cases of melanoma and other malignancies have been reported.

Such changes are rare enough that most experts consider prophylactic removal to be unwarranted. Watching the lesions for change over the years is certainly reasonable, as is protecting them from sun exposure.

Surgical removal—usually performed by a plastic surgeon—is occasionally necessary for cosmetic reasons. This is particularly so when NS covers a portion of the face, or when the cosmetic implications of having a hairless plaque in the scalp are sufficiently distressing.

This patient and her parents were educated about the nature of the diagnosis and apprised of their options.

Editor's note: For a similar presentation with a very different diagnosis, see the March 2015 DermaDiagnosis case (http://bit.ly/1ye69Ym).

ANSWER
The correct answer is nevus sebaceous (choice “a”). This benign hamartomatous lesion is derived from local tissue and grows at the same rate.

It differs considerably from the other items in the differential, including aplasia cutis congenita (choice “b”). In this condition, a focal area of epidermis simply fails to develop, leaving a permanent hairless scar that contrasts sharply with the raised, mammillated plaque of nevus sebaceous.

Epidermal nevus (choice “c”) is usually a collection of tan to brown superficial nevoid papules that can be linear, agminated, or plaque-like. These lesions lack the color and mammillated surface of those seen in nevus sebaceous.

Neonatal lupus (choice “d”) can present at birth with hairless, cicatricial inflamed lesions. However, these tend to resolve quickly, often leaving focal scarring alopecia but no plaque formation.

DISCUSSION
Nevus sebaceous (NS), first described by Jadassohn in 1895, has long been recognized as an unusual but by no means rare congenital lesion. Occurring equally in both sexes and comprising ­sebaceous glands in a nevoid morphologic context, NS is considered a variant of sebaceous nevi and verrucous epidermal nevi in some circles. All three are derived from overgrowth of local, normal tissues that typically grow at the same rate as surrounding structures.

The vast majority of NS lesions are found in the scalp, although they can also develop on the ear or neck and, rarely, elsewhere on the body. This patient’s plaque—with its uniform surface; tiny, smooth, shiny papules; and (perhaps most important) total lack of hair—is typical. Other classic features are congenital onset and permanent nature, which distinguish them from the rest of the differential.

Focal malignant transformation of NS lesions has been reported—in fact, this author has seen two such cases in 30 years. Both were small basal cell carcinomas, although cases of melanoma and other malignancies have been reported.

Such changes are rare enough that most experts consider prophylactic removal to be unwarranted. Watching the lesions for change over the years is certainly reasonable, as is protecting them from sun exposure.

Surgical removal—usually performed by a plastic surgeon—is occasionally necessary for cosmetic reasons. This is particularly so when NS covers a portion of the face, or when the cosmetic implications of having a hairless plaque in the scalp are sufficiently distressing.

This patient and her parents were educated about the nature of the diagnosis and apprised of their options.

Editor's note: For a similar presentation with a very different diagnosis, see the March 2015 DermaDiagnosis case (http://bit.ly/1ye69Ym).

ANSWER
The correct answer is nevus sebaceous (choice “a”). This benign hamartomatous lesion is derived from local tissue and grows at the same rate.

It differs considerably from the other items in the differential, including aplasia cutis congenita (choice “b”). In this condition, a focal area of epidermis simply fails to develop, leaving a permanent hairless scar that contrasts sharply with the raised, mammillated plaque of nevus sebaceous.

Epidermal nevus (choice “c”) is usually a collection of tan to brown superficial nevoid papules that can be linear, agminated, or plaque-like. These lesions lack the color and mammillated surface of those seen in nevus sebaceous.

Neonatal lupus (choice “d”) can present at birth with hairless, cicatricial inflamed lesions. However, these tend to resolve quickly, often leaving focal scarring alopecia but no plaque formation.

DISCUSSION
Nevus sebaceous (NS), first described by Jadassohn in 1895, has long been recognized as an unusual but by no means rare congenital lesion. Occurring equally in both sexes and comprising ­sebaceous glands in a nevoid morphologic context, NS is considered a variant of sebaceous nevi and verrucous epidermal nevi in some circles. All three are derived from overgrowth of local, normal tissues that typically grow at the same rate as surrounding structures.

The vast majority of NS lesions are found in the scalp, although they can also develop on the ear or neck and, rarely, elsewhere on the body. This patient’s plaque—with its uniform surface; tiny, smooth, shiny papules; and (perhaps most important) total lack of hair—is typical. Other classic features are congenital onset and permanent nature, which distinguish them from the rest of the differential.

Focal malignant transformation of NS lesions has been reported—in fact, this author has seen two such cases in 30 years. Both were small basal cell carcinomas, although cases of melanoma and other malignancies have been reported.

Such changes are rare enough that most experts consider prophylactic removal to be unwarranted. Watching the lesions for change over the years is certainly reasonable, as is protecting them from sun exposure.

Surgical removal—usually performed by a plastic surgeon—is occasionally necessary for cosmetic reasons. This is particularly so when NS covers a portion of the face, or when the cosmetic implications of having a hairless plaque in the scalp are sufficiently distressing.

This patient and her parents were educated about the nature of the diagnosis and apprised of their options.

Editor's note: For a similar presentation with a very different diagnosis, see the March 2015 DermaDiagnosis case (http://bit.ly/1ye69Ym).

EVIDENCE SUMMARY

One-fifth of patients with diabetes who have foot ulcerations will develop osteomyelitis.^1,2 Most cases of diabetic foot osteomyelitis result from the spread of a foot infection to underlying bone.²

MRI has highest sensitivity, probe to bone test is most specific

A meta-analysis³ of 9 cohort trials (8 prospective, 1 retrospective) of 612 patients with diabetes and a foot ulcer examined the accuracy of diagnostic methods for osteomyelitis (TABLE^3,4). MRI had the highest sensitivity (90%), followed by bone scan (81%). Bone scan was the least specific (28%), however. Plain film radiography had the lowest sensitivity (54%). A PTB test was highly specific (91%) but had moderate sensitivity (60%). (PTB involves inserting a sterile, blunt stainless steel probe into an ulcerated lesion. If the probe comes to a hard stop, considered to be bone, the test is positive.)

A meta-analysis of 21 prospective and retrospective trials with 1027 diabetic patients with foot ulcers or suspected osteomyelitis found that ulcer size >2 cm², PTB, and ESR >70 mm/hr were helpful in making the diagnosis.⁴

Combining ESR with ulcer size increases specificity

A prospective trial of 46 diabetic patients hospitalized with a foot infection examined the accuracy of a combination of clinical and laboratory diagnostic features in patients with diabetic foot osteomyelitis that had been diagnosed by MRI or histopathology.⁵ (Twenty-four patients had osteomyelitis, and 22 didn’t.)

ESR >70 mm/hr had a sensitivity of 83% and specificity of 77% (positive likelihood ratio [LR+]=3.6; negative likelihood ratio [LR−]=0.22). Ulcer size >2 cm2 had a sensitivity of 88% and specificity of 77% (LR+=3.8; LR−=0.16). Combined, an ESR >70 mm/hr and ulcer size >2cm² had a slightly better specificity than either finding alone, 82%, but a lower sensitivity of 79% (LR+=4.4; LR−= 0.26).

Serum markers accurately distinguish osteomyelitis from infection

An individual prospective cohort trial of 61 adult patients with diabetes and a foot infection, published after the meta-analysis⁴ described previously, examined the accuracy of serum markers (ESR, CRP, procalcitonin) for diagnosing osteomyelitis.⁶ A positive PTB test and imaging study (plain film, MRI, or nuclear scintigraphy) were used as the diagnostic gold standard.

Thirty-four patients had a soft tissue infection and 27 had osteomyelitis. All markers were higher in patients with osteomyelitis than in patients with a soft tissue infection (ESR=76 mm/hr vs 66 mm/hr; P<.001; CRP=25 mg/L vs 8.7 mg/L; P<.001; procalcitonin=2.4 ng/mL vs 0.71 ng/mL; P<.001). The sensitivity and specificity for each marker at its optimum points were: ESR >67 mm/hr (sensitivity 84%; specificity 75%; LR+=3.4; LR−=0.21); CRP >14 mg/L (sensitivity 85%; specificity 83%; LR+=5; LR−=0.18); and procalcitonin >0.3 ng/mL (sensitivity 81%; specificity 71%; LR+=2.8; LR−=0.27).

RECOMMENDATIONS

The Infectious Diseases Society of America (IDSA) recommends performing the PTB test on any diabetic foot infection with an open wound (level of evidence: strong moderate).⁷ It also recommends performing plain radiography on all patients presenting with a new infection to evaluate for bony abnormalities, soft tissue gas, and foreign bodies (level of evidence: strong moderate).

The IDSA, the American College of Radiology diagnostic imaging expert panel, and the National Institute for Health and Clinical Excellence recommend using MRI in most clinical scenarios when osteomyelitis is suspected (level of evidence: strong moderate).^8,9

EVIDENCE SUMMARY

One-fifth of patients with diabetes who have foot ulcerations will develop osteomyelitis.^1,2 Most cases of diabetic foot osteomyelitis result from the spread of a foot infection to underlying bone.²

MRI has highest sensitivity, probe to bone test is most specific

A meta-analysis³ of 9 cohort trials (8 prospective, 1 retrospective) of 612 patients with diabetes and a foot ulcer examined the accuracy of diagnostic methods for osteomyelitis (TABLE^3,4). MRI had the highest sensitivity (90%), followed by bone scan (81%). Bone scan was the least specific (28%), however. Plain film radiography had the lowest sensitivity (54%). A PTB test was highly specific (91%) but had moderate sensitivity (60%). (PTB involves inserting a sterile, blunt stainless steel probe into an ulcerated lesion. If the probe comes to a hard stop, considered to be bone, the test is positive.)

A meta-analysis of 21 prospective and retrospective trials with 1027 diabetic patients with foot ulcers or suspected osteomyelitis found that ulcer size >2 cm², PTB, and ESR >70 mm/hr were helpful in making the diagnosis.⁴

Combining ESR with ulcer size increases specificity

A prospective trial of 46 diabetic patients hospitalized with a foot infection examined the accuracy of a combination of clinical and laboratory diagnostic features in patients with diabetic foot osteomyelitis that had been diagnosed by MRI or histopathology.⁵ (Twenty-four patients had osteomyelitis, and 22 didn’t.)

ESR >70 mm/hr had a sensitivity of 83% and specificity of 77% (positive likelihood ratio [LR+]=3.6; negative likelihood ratio [LR−]=0.22). Ulcer size >2 cm2 had a sensitivity of 88% and specificity of 77% (LR+=3.8; LR−=0.16). Combined, an ESR >70 mm/hr and ulcer size >2cm² had a slightly better specificity than either finding alone, 82%, but a lower sensitivity of 79% (LR+=4.4; LR−= 0.26).

Serum markers accurately distinguish osteomyelitis from infection

An individual prospective cohort trial of 61 adult patients with diabetes and a foot infection, published after the meta-analysis⁴ described previously, examined the accuracy of serum markers (ESR, CRP, procalcitonin) for diagnosing osteomyelitis.⁶ A positive PTB test and imaging study (plain film, MRI, or nuclear scintigraphy) were used as the diagnostic gold standard.

Thirty-four patients had a soft tissue infection and 27 had osteomyelitis. All markers were higher in patients with osteomyelitis than in patients with a soft tissue infection (ESR=76 mm/hr vs 66 mm/hr; P<.001; CRP=25 mg/L vs 8.7 mg/L; P<.001; procalcitonin=2.4 ng/mL vs 0.71 ng/mL; P<.001). The sensitivity and specificity for each marker at its optimum points were: ESR >67 mm/hr (sensitivity 84%; specificity 75%; LR+=3.4; LR−=0.21); CRP >14 mg/L (sensitivity 85%; specificity 83%; LR+=5; LR−=0.18); and procalcitonin >0.3 ng/mL (sensitivity 81%; specificity 71%; LR+=2.8; LR−=0.27).

RECOMMENDATIONS

The Infectious Diseases Society of America (IDSA) recommends performing the PTB test on any diabetic foot infection with an open wound (level of evidence: strong moderate).⁷ It also recommends performing plain radiography on all patients presenting with a new infection to evaluate for bony abnormalities, soft tissue gas, and foreign bodies (level of evidence: strong moderate).

The IDSA, the American College of Radiology diagnostic imaging expert panel, and the National Institute for Health and Clinical Excellence recommend using MRI in most clinical scenarios when osteomyelitis is suspected (level of evidence: strong moderate).^8,9

EVIDENCE SUMMARY

One-fifth of patients with diabetes who have foot ulcerations will develop osteomyelitis.^1,2 Most cases of diabetic foot osteomyelitis result from the spread of a foot infection to underlying bone.²

MRI has highest sensitivity, probe to bone test is most specific

A meta-analysis³ of 9 cohort trials (8 prospective, 1 retrospective) of 612 patients with diabetes and a foot ulcer examined the accuracy of diagnostic methods for osteomyelitis (TABLE^3,4). MRI had the highest sensitivity (90%), followed by bone scan (81%). Bone scan was the least specific (28%), however. Plain film radiography had the lowest sensitivity (54%). A PTB test was highly specific (91%) but had moderate sensitivity (60%). (PTB involves inserting a sterile, blunt stainless steel probe into an ulcerated lesion. If the probe comes to a hard stop, considered to be bone, the test is positive.)

A meta-analysis of 21 prospective and retrospective trials with 1027 diabetic patients with foot ulcers or suspected osteomyelitis found that ulcer size >2 cm², PTB, and ESR >70 mm/hr were helpful in making the diagnosis.⁴

Combining ESR with ulcer size increases specificity

A prospective trial of 46 diabetic patients hospitalized with a foot infection examined the accuracy of a combination of clinical and laboratory diagnostic features in patients with diabetic foot osteomyelitis that had been diagnosed by MRI or histopathology.⁵ (Twenty-four patients had osteomyelitis, and 22 didn’t.)

ESR >70 mm/hr had a sensitivity of 83% and specificity of 77% (positive likelihood ratio [LR+]=3.6; negative likelihood ratio [LR−]=0.22). Ulcer size >2 cm2 had a sensitivity of 88% and specificity of 77% (LR+=3.8; LR−=0.16). Combined, an ESR >70 mm/hr and ulcer size >2cm² had a slightly better specificity than either finding alone, 82%, but a lower sensitivity of 79% (LR+=4.4; LR−= 0.26).

Serum markers accurately distinguish osteomyelitis from infection

An individual prospective cohort trial of 61 adult patients with diabetes and a foot infection, published after the meta-analysis⁴ described previously, examined the accuracy of serum markers (ESR, CRP, procalcitonin) for diagnosing osteomyelitis.⁶ A positive PTB test and imaging study (plain film, MRI, or nuclear scintigraphy) were used as the diagnostic gold standard.

Thirty-four patients had a soft tissue infection and 27 had osteomyelitis. All markers were higher in patients with osteomyelitis than in patients with a soft tissue infection (ESR=76 mm/hr vs 66 mm/hr; P<.001; CRP=25 mg/L vs 8.7 mg/L; P<.001; procalcitonin=2.4 ng/mL vs 0.71 ng/mL; P<.001). The sensitivity and specificity for each marker at its optimum points were: ESR >67 mm/hr (sensitivity 84%; specificity 75%; LR+=3.4; LR−=0.21); CRP >14 mg/L (sensitivity 85%; specificity 83%; LR+=5; LR−=0.18); and procalcitonin >0.3 ng/mL (sensitivity 81%; specificity 71%; LR+=2.8; LR−=0.27).

RECOMMENDATIONS

The Infectious Diseases Society of America (IDSA) recommends performing the PTB test on any diabetic foot infection with an open wound (level of evidence: strong moderate).⁷ It also recommends performing plain radiography on all patients presenting with a new infection to evaluate for bony abnormalities, soft tissue gas, and foreign bodies (level of evidence: strong moderate).

The IDSA, the American College of Radiology diagnostic imaging expert panel, and the National Institute for Health and Clinical Excellence recommend using MRI in most clinical scenarios when osteomyelitis is suspected (level of evidence: strong moderate).^8,9

ASHEVILLE, N.C. – What are the risk factors for invasive melanoma in patients with lentigo maligna? Size, for one thing, according to Dr. Suzanne M. Olbricht.

In an interview at the annual meeting of the Noah Worcester Dermatological Society, Dr. Olbricht of the Lahey Hospital and Medical Center in Burlington, Mass., reviewed evidence suggesting that the recurrence rate is highest for large lesions. “This is important information that helps us think about the treatments we can use,” she said.

Dr. Olbricht had no financial conflicts to disclose.

[email protected]

ASHEVILLE, N.C. – What are the risk factors for invasive melanoma in patients with lentigo maligna? Size, for one thing, according to Dr. Suzanne M. Olbricht.

In an interview at the annual meeting of the Noah Worcester Dermatological Society, Dr. Olbricht of the Lahey Hospital and Medical Center in Burlington, Mass., reviewed evidence suggesting that the recurrence rate is highest for large lesions. “This is important information that helps us think about the treatments we can use,” she said.

Dr. Olbricht had no financial conflicts to disclose.

[email protected]

ASHEVILLE, N.C. – What are the risk factors for invasive melanoma in patients with lentigo maligna? Size, for one thing, according to Dr. Suzanne M. Olbricht.

In an interview at the annual meeting of the Noah Worcester Dermatological Society, Dr. Olbricht of the Lahey Hospital and Medical Center in Burlington, Mass., reviewed evidence suggesting that the recurrence rate is highest for large lesions. “This is important information that helps us think about the treatments we can use,” she said.

Dr. Olbricht had no financial conflicts to disclose.

[email protected]

A 22-year-old woman with a history of attention-deficit/hyperactivity disorder and childhood asthma came to the emergency department (ED) for treatment of a cramping, substernal, pleuritic chest pain she’d had for a week and the feeling of a “lump in her throat” that made it difficult and painful for her to swallow. The patient’s vital signs were normal and her substernal chest pain was reproducible with palpation. An anteroposterior (AP) chest x-ray (CXR) was unremarkable.

A “GI cocktail” (lidocaine, Mylanta and Donnatal), ketorolac, morphine, and lorazepam were administered in the ED, but did not provide the patient with any relief. She was admitted to the hospital to rule out acute coronary syndrome and was kept NPO overnight. A repeat CXR with posteroanterior (PA) and lateral views was also obtained (FIGURE 1A AND 1B).

WHAT IS YOUR DIAGNOSIS?
HOW WOULD YOU TREAT THIS PATIENT?

The PA and lateral view CXRs revealed the presence of retrosternal air, suggesting the patient had pneumomediastinum. A computed tomography (CT) scan of the chest also showed retrosternal air (FIGURE 2A AND 2B, arrows) and confirmed this diagnosis. To rule out esophageal perforation, the team ordered Gastrografin and barium swallow studies. The patient was kept NPO until both studies were confirmed to be negative.

Patients with pneumomediastinum will report retrosternal, pleuritic pain and may also have difficulty swallowing.

Pneumomediastinum—the presence of free air in the mediastinum—can develop spontaneously (as was the case with our patient) or in response to trauma. Common causes include respiratory diseases such as asthma, and trauma to the esophagus secondary to mechanical ventilation, endoscopy, and excessive vomiting.¹ Other possible causes include respiratory infections, foreign body aspiration, recent dental extraction, diabetic ketoacidosis, esophageal perforation, barotrauma (due to activities such as flying or scuba diving), and use of illicit drugs.¹

Patients with pneumomediastinum often complain of retrosternal, pleuritic pain that radiates to their back, shoulders, and arms. They may also have difficulty swallowing (globus pharyngeus), a nasal voice, and/or dyspnea. Physical findings can include subcutaneous emphysema in the neck and supraclavicular fossa as manifested by Hamman’s sign (a precordial “crunching” sound heard during systole), a fever, and distended neck veins.¹

Differential diagnosis includes inflammatory conditions

The differential diagnosis for pneumomediastinum includes pericarditis, mediastinitis, Boerhaave syndrome, and acute coronary syndrome.

Pericarditis. In a patient with inflammation of the pericardium, you would hear reduced heart sounds and observe electrocardiogram (EKG) changes (eg, diffuse ST elevation in acute pericarditis). These signs typically would not be present in a patient with pneumomediastinum.¹

Mediastinitis. Patients with mediastinitis—inflammation of the mediastinum—are more likely to have hypotension and shock.¹

Boerhaave syndrome, or spontaneous esophageal perforation, has a similar presentation to pneumomediastinum but is more likely to be accompanied by hypotension and shock. Additionally, there would be extravasation of the contrast agent during swallow studies.²

Acute coronary syndrome is also part of the differential. However, in ACS, you would see ST changes on the patient’s EKG and elevated cardiac enzymes.¹

Lateral x-rays are especially useful in making the diagnosis

Diagnosis is made by CXR and/or chest CT. On a CXR, retrosternal air is best seen in the lateral projection. Small amounts of air can appear as linear lucencies outlining mediastinal contours. This air can be seen under the skin, surrounding the pericardium, around the pulmonary and/or aortic vasculature, and/or between the parietal pleura and diaphragm.² A pleural effusion—particularly on the patient’s left side—should raise concern for esophageal perforation.

For most patients, rest and pain control are key

Because pneumomediastinum is generally a self-limiting condition, patients who don’t have severe symptoms, such as respiratory distress or signs of inflammation, should be observed for 2 days, managed with rest and pain control, and discharged home.

If severe symptoms or inflammatory signs are present, a Gastrografin swallow study is recommended to rule out esophageal perforation. If the result of this test is abnormal, a follow-up study with barium is recommended.³ Gastrografin swallow studies are the preferred initial study.³ A barium swallow study is more sensitive, but has a higher risk of causing pneumomediastinitis if an esophageal perforation is present.²

If the swallow study reveals a perforation, surgical decompression and antibiotics may be necessary.^1,4,5

Our patient received subsequent serial CXRs that showed improvement in pneumomediastinum. Once our patient’s pain was well controlled with oral nonsteroidal anti-inflammatory drugs, she was discharged home after a 3-day hospitalization with close follow-up. One week later, she had no further complaints and her pain had almost entirely resolved.

CORRESPONDENCE
Breanna Gawrys, DO, Fort Belvoir Community Hospital Family Medicine Residency, 9300 DeWitt Loop, Fort Belvoir, VA 22060; [email protected]

A 22-year-old woman with a history of attention-deficit/hyperactivity disorder and childhood asthma came to the emergency department (ED) for treatment of a cramping, substernal, pleuritic chest pain she’d had for a week and the feeling of a “lump in her throat” that made it difficult and painful for her to swallow. The patient’s vital signs were normal and her substernal chest pain was reproducible with palpation. An anteroposterior (AP) chest x-ray (CXR) was unremarkable.

A “GI cocktail” (lidocaine, Mylanta and Donnatal), ketorolac, morphine, and lorazepam were administered in the ED, but did not provide the patient with any relief. She was admitted to the hospital to rule out acute coronary syndrome and was kept NPO overnight. A repeat CXR with posteroanterior (PA) and lateral views was also obtained (FIGURE 1A AND 1B).

WHAT IS YOUR DIAGNOSIS?
HOW WOULD YOU TREAT THIS PATIENT?

The PA and lateral view CXRs revealed the presence of retrosternal air, suggesting the patient had pneumomediastinum. A computed tomography (CT) scan of the chest also showed retrosternal air (FIGURE 2A AND 2B, arrows) and confirmed this diagnosis. To rule out esophageal perforation, the team ordered Gastrografin and barium swallow studies. The patient was kept NPO until both studies were confirmed to be negative.

Patients with pneumomediastinum will report retrosternal, pleuritic pain and may also have difficulty swallowing.

Pneumomediastinum—the presence of free air in the mediastinum—can develop spontaneously (as was the case with our patient) or in response to trauma. Common causes include respiratory diseases such as asthma, and trauma to the esophagus secondary to mechanical ventilation, endoscopy, and excessive vomiting.¹ Other possible causes include respiratory infections, foreign body aspiration, recent dental extraction, diabetic ketoacidosis, esophageal perforation, barotrauma (due to activities such as flying or scuba diving), and use of illicit drugs.¹

Patients with pneumomediastinum often complain of retrosternal, pleuritic pain that radiates to their back, shoulders, and arms. They may also have difficulty swallowing (globus pharyngeus), a nasal voice, and/or dyspnea. Physical findings can include subcutaneous emphysema in the neck and supraclavicular fossa as manifested by Hamman’s sign (a precordial “crunching” sound heard during systole), a fever, and distended neck veins.¹

Differential diagnosis includes inflammatory conditions

The differential diagnosis for pneumomediastinum includes pericarditis, mediastinitis, Boerhaave syndrome, and acute coronary syndrome.

Pericarditis. In a patient with inflammation of the pericardium, you would hear reduced heart sounds and observe electrocardiogram (EKG) changes (eg, diffuse ST elevation in acute pericarditis). These signs typically would not be present in a patient with pneumomediastinum.¹

Mediastinitis. Patients with mediastinitis—inflammation of the mediastinum—are more likely to have hypotension and shock.¹

Boerhaave syndrome, or spontaneous esophageal perforation, has a similar presentation to pneumomediastinum but is more likely to be accompanied by hypotension and shock. Additionally, there would be extravasation of the contrast agent during swallow studies.²

Acute coronary syndrome is also part of the differential. However, in ACS, you would see ST changes on the patient’s EKG and elevated cardiac enzymes.¹

Lateral x-rays are especially useful in making the diagnosis

Diagnosis is made by CXR and/or chest CT. On a CXR, retrosternal air is best seen in the lateral projection. Small amounts of air can appear as linear lucencies outlining mediastinal contours. This air can be seen under the skin, surrounding the pericardium, around the pulmonary and/or aortic vasculature, and/or between the parietal pleura and diaphragm.² A pleural effusion—particularly on the patient’s left side—should raise concern for esophageal perforation.

For most patients, rest and pain control are key

Because pneumomediastinum is generally a self-limiting condition, patients who don’t have severe symptoms, such as respiratory distress or signs of inflammation, should be observed for 2 days, managed with rest and pain control, and discharged home.

If severe symptoms or inflammatory signs are present, a Gastrografin swallow study is recommended to rule out esophageal perforation. If the result of this test is abnormal, a follow-up study with barium is recommended.³ Gastrografin swallow studies are the preferred initial study.³ A barium swallow study is more sensitive, but has a higher risk of causing pneumomediastinitis if an esophageal perforation is present.²

If the swallow study reveals a perforation, surgical decompression and antibiotics may be necessary.^1,4,5

Our patient received subsequent serial CXRs that showed improvement in pneumomediastinum. Once our patient’s pain was well controlled with oral nonsteroidal anti-inflammatory drugs, she was discharged home after a 3-day hospitalization with close follow-up. One week later, she had no further complaints and her pain had almost entirely resolved.

CORRESPONDENCE
Breanna Gawrys, DO, Fort Belvoir Community Hospital Family Medicine Residency, 9300 DeWitt Loop, Fort Belvoir, VA 22060; [email protected]

A 22-year-old woman with a history of attention-deficit/hyperactivity disorder and childhood asthma came to the emergency department (ED) for treatment of a cramping, substernal, pleuritic chest pain she’d had for a week and the feeling of a “lump in her throat” that made it difficult and painful for her to swallow. The patient’s vital signs were normal and her substernal chest pain was reproducible with palpation. An anteroposterior (AP) chest x-ray (CXR) was unremarkable.

A “GI cocktail” (lidocaine, Mylanta and Donnatal), ketorolac, morphine, and lorazepam were administered in the ED, but did not provide the patient with any relief. She was admitted to the hospital to rule out acute coronary syndrome and was kept NPO overnight. A repeat CXR with posteroanterior (PA) and lateral views was also obtained (FIGURE 1A AND 1B).

WHAT IS YOUR DIAGNOSIS?
HOW WOULD YOU TREAT THIS PATIENT?

The PA and lateral view CXRs revealed the presence of retrosternal air, suggesting the patient had pneumomediastinum. A computed tomography (CT) scan of the chest also showed retrosternal air (FIGURE 2A AND 2B, arrows) and confirmed this diagnosis. To rule out esophageal perforation, the team ordered Gastrografin and barium swallow studies. The patient was kept NPO until both studies were confirmed to be negative.

Patients with pneumomediastinum will report retrosternal, pleuritic pain and may also have difficulty swallowing.

Pneumomediastinum—the presence of free air in the mediastinum—can develop spontaneously (as was the case with our patient) or in response to trauma. Common causes include respiratory diseases such as asthma, and trauma to the esophagus secondary to mechanical ventilation, endoscopy, and excessive vomiting.¹ Other possible causes include respiratory infections, foreign body aspiration, recent dental extraction, diabetic ketoacidosis, esophageal perforation, barotrauma (due to activities such as flying or scuba diving), and use of illicit drugs.¹

Patients with pneumomediastinum often complain of retrosternal, pleuritic pain that radiates to their back, shoulders, and arms. They may also have difficulty swallowing (globus pharyngeus), a nasal voice, and/or dyspnea. Physical findings can include subcutaneous emphysema in the neck and supraclavicular fossa as manifested by Hamman’s sign (a precordial “crunching” sound heard during systole), a fever, and distended neck veins.¹

Differential diagnosis includes inflammatory conditions

The differential diagnosis for pneumomediastinum includes pericarditis, mediastinitis, Boerhaave syndrome, and acute coronary syndrome.

Pericarditis. In a patient with inflammation of the pericardium, you would hear reduced heart sounds and observe electrocardiogram (EKG) changes (eg, diffuse ST elevation in acute pericarditis). These signs typically would not be present in a patient with pneumomediastinum.¹

Mediastinitis. Patients with mediastinitis—inflammation of the mediastinum—are more likely to have hypotension and shock.¹

Boerhaave syndrome, or spontaneous esophageal perforation, has a similar presentation to pneumomediastinum but is more likely to be accompanied by hypotension and shock. Additionally, there would be extravasation of the contrast agent during swallow studies.²

Acute coronary syndrome is also part of the differential. However, in ACS, you would see ST changes on the patient’s EKG and elevated cardiac enzymes.¹

Lateral x-rays are especially useful in making the diagnosis

Diagnosis is made by CXR and/or chest CT. On a CXR, retrosternal air is best seen in the lateral projection. Small amounts of air can appear as linear lucencies outlining mediastinal contours. This air can be seen under the skin, surrounding the pericardium, around the pulmonary and/or aortic vasculature, and/or between the parietal pleura and diaphragm.² A pleural effusion—particularly on the patient’s left side—should raise concern for esophageal perforation.

For most patients, rest and pain control are key

Because pneumomediastinum is generally a self-limiting condition, patients who don’t have severe symptoms, such as respiratory distress or signs of inflammation, should be observed for 2 days, managed with rest and pain control, and discharged home.

If severe symptoms or inflammatory signs are present, a Gastrografin swallow study is recommended to rule out esophageal perforation. If the result of this test is abnormal, a follow-up study with barium is recommended.³ Gastrografin swallow studies are the preferred initial study.³ A barium swallow study is more sensitive, but has a higher risk of causing pneumomediastinitis if an esophageal perforation is present.²

If the swallow study reveals a perforation, surgical decompression and antibiotics may be necessary.^1,4,5

Our patient received subsequent serial CXRs that showed improvement in pneumomediastinum. Once our patient’s pain was well controlled with oral nonsteroidal anti-inflammatory drugs, she was discharged home after a 3-day hospitalization with close follow-up. One week later, she had no further complaints and her pain had almost entirely resolved.

CORRESPONDENCE
Breanna Gawrys, DO, Fort Belvoir Community Hospital Family Medicine Residency, 9300 DeWitt Loop, Fort Belvoir, VA 22060; [email protected]

Illustrative case

A 22-year-old G2P1 pregnant woman at 18 weeks gestation who has a history of preeclampsia comes to your office for a routine prenatal visit. On exam, her blood pressure continues to be in the 110s/60s, as it has been for several visits. Her history puts her at risk of developing preeclampsia again, and you wonder if anything can be done to prevent this from happening.

The incidence of preeclampsia, which occurs in 2% to 8% of pregnancies worldwide and 3.4% of pregnancies in the United States, appears to be steadily increasing.^2,3 Preeclampsia is defined as new-onset hypertension at >20 weeks gestation, plus proteinuria, thrombocytopenia, renal insufficiency, impaired liver function, pulmonary edema, and/or cerebral or visual symptoms.⁴ The condition is associated with several adverse maternal and fetal outcomes, including eclampsia, abruption, intrauterine growth restriction (IUGR), preterm birth, stillbirth, and maternal death.^2,4 Risk factors for preeclampsia include previous preeclampsia, maternal age ≥40 years, chronic medical conditions, and multi-fetal pregnancy.⁵

The only effective treatment for preeclampsia is delivery.⁴ Given the lack of other treatments, strategies for preventing preeclampsia would be highly valuable.

In 1996, the US Preventive Services Task Force (USPSTF) addressed this issue and concluded that there was insufficient evidence to recommend for or against using aspirin to prevent preeclampsia.⁶ More recently, Henderson et al¹ conducted a systematic review and meta-analysis to support the USPSTF in a revision of its earlier recommendation.

STUDY SUMMARY: Aspirin use lowers risk of preeclampsia and preterm birth

Henderson et al¹ evaluated the impact of low-dose aspirin on maternal and fetal outcomes among pregnant women at risk for preeclampsia. The review of 23 studies included 21 randomized placebo-controlled trials that evaluated 24,666 patients. Slightly more than half of the studies that evaluated maternal and fetal health benefits were graded as good-quality, and 67% of those that evaluated maternal, perinatal, and developmental harms were rated good-quality.

Most women were white and ages 20 to 33 years. Aspirin doses ranged from 60 mg/d to 150 mg/d; most studies used 60 mg/d or 100 mg/d. Aspirin was initiated between 12 to 36 weeks gestation, with 9 trials initiating aspirin before 16 weeks. In most trials, aspirin was continued until delivery.

Among women at high preeclampsia risk (10 studies), the pooled relative risk (RR) for perinatal death was 0.81 (95% confidence interval [CI], 0.65-1.01) for low-dose aspirin compared to placebo. However, this finding was not statistically significant (P=.78).

Researchers found no evidence of increased maternal postpartum hemorrhage with aspirin use.

Among women who received low-dose aspirin, researchers noted a 14% risk reduction for preterm birth (RR=0.86; 95% CI, 0.76-0.98); a 20% risk reduction for IUGR (RR=0.80; 95% CI, 0.65-0.99), and a 24% risk reduction for preeclampsia (RR=0.76; 95% CI, 0.62-0.95). The absolute risk reduction for preeclampsia was estimated to be 2% to 5%.

While the results for preterm birth, IUGR, and preeclampsia were statistically significant, the authors noted that these results could have been biased by small study effects (the tendency of smaller studies to report positive findings, which in turn can skew the results of a meta-analysis based primarily on such studies). The timing and dosage of aspirin had no significant effect on outcomes.

There was no evidence of increased maternal postpartum hemorrhage with aspirin use (RR=1.02; 95% CI, 0.96-1.09). Aspirin use did not seem to increase perinatal mortality among all risk levels (RR=0.92; 95% CI, 0.76-1.11; P=.65). No differences were noted in the toddlers’ development at 18 months.

WHAT'S NEW: Low-dose aspirin use is now recommended

The 1996 USPSTF recommendation concluded that there was insufficient evidence to recommend aspirin use for preventing preeclampsia. This systematic review and meta-analysis, along with findings from a 2007 Cochrane review⁷ and a meta-analysis from the PARIS Collaborative Group,⁸ provide good-quality evidence that aspirin reduces negative maternal and fetal outcomes associated with preeclampsia. In 2014, the USPSTF cited this evidence when it decided to recommend using low-dose aspirin (81 mg/d) to prevent preeclampsia in women who are at high risk for preeclampsia (Grade B).⁹ (For more on the USPSTF, see “Catching up on the latest USPSTF recommendations”.)

CAVEATS: Much of the data came from small studies

A substantial portion of the data in this systematic review and meta-analysis came from small studies with positive findings. Because small studies with null findings tend to not be published, there is concern that the results reported by Henderson et al¹ may be somewhat biased, and that future studies may push the overall observed effect toward a null finding.

Also, the criteria used to define “high risk” for preeclampsia varied by study, so it’s unclear which groups of women would benefit most from aspirin use during pregnancy. Finally, there is a lack of high-quality data on the effects of aspirin use during pregnancy on long-term outcomes in children. Despite these caveats, the cumulative evidence strongly points to greater benefit than harm.

CHALLENGES TO IMPLEMENTATION: You need to determine which patients are at highest risk

The principle challenge lies in identifying which patients are at high risk for preeclampsia, and thus, will likely benefit from this intervention. This systematic review and meta-analysis used a large variety of risk factors to determine whether a woman was high risk. A 2013 American College of Obstetricians and Gynecologists Task Force on Hypertension in Pregnancy report defined high-risk as women with a history of preeclampsia in more than one previous pregnancy or women with a previous preterm delivery due to preeclampsia.⁴

The updated USPSTF recommendation suggests that women be considered high risk if they have any of the following: 1) previous preeclampsia, 2) multifetal gestation, 3) chronic hypertension, 4) diabetes, 5) renal disease, or 6) autoimmune disease.⁹ We consider both sets of criteria reasonable for identifying women who may benefit from low-dose aspirin during pregnancy.

ACKNOWLEDGEMENT
The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.

Illustrative case

A 22-year-old G2P1 pregnant woman at 18 weeks gestation who has a history of preeclampsia comes to your office for a routine prenatal visit. On exam, her blood pressure continues to be in the 110s/60s, as it has been for several visits. Her history puts her at risk of developing preeclampsia again, and you wonder if anything can be done to prevent this from happening.

The incidence of preeclampsia, which occurs in 2% to 8% of pregnancies worldwide and 3.4% of pregnancies in the United States, appears to be steadily increasing.^2,3 Preeclampsia is defined as new-onset hypertension at >20 weeks gestation, plus proteinuria, thrombocytopenia, renal insufficiency, impaired liver function, pulmonary edema, and/or cerebral or visual symptoms.⁴ The condition is associated with several adverse maternal and fetal outcomes, including eclampsia, abruption, intrauterine growth restriction (IUGR), preterm birth, stillbirth, and maternal death.^2,4 Risk factors for preeclampsia include previous preeclampsia, maternal age ≥40 years, chronic medical conditions, and multi-fetal pregnancy.⁵

The only effective treatment for preeclampsia is delivery.⁴ Given the lack of other treatments, strategies for preventing preeclampsia would be highly valuable.

In 1996, the US Preventive Services Task Force (USPSTF) addressed this issue and concluded that there was insufficient evidence to recommend for or against using aspirin to prevent preeclampsia.⁶ More recently, Henderson et al¹ conducted a systematic review and meta-analysis to support the USPSTF in a revision of its earlier recommendation.

STUDY SUMMARY: Aspirin use lowers risk of preeclampsia and preterm birth

Henderson et al¹ evaluated the impact of low-dose aspirin on maternal and fetal outcomes among pregnant women at risk for preeclampsia. The review of 23 studies included 21 randomized placebo-controlled trials that evaluated 24,666 patients. Slightly more than half of the studies that evaluated maternal and fetal health benefits were graded as good-quality, and 67% of those that evaluated maternal, perinatal, and developmental harms were rated good-quality.

Most women were white and ages 20 to 33 years. Aspirin doses ranged from 60 mg/d to 150 mg/d; most studies used 60 mg/d or 100 mg/d. Aspirin was initiated between 12 to 36 weeks gestation, with 9 trials initiating aspirin before 16 weeks. In most trials, aspirin was continued until delivery.

Among women at high preeclampsia risk (10 studies), the pooled relative risk (RR) for perinatal death was 0.81 (95% confidence interval [CI], 0.65-1.01) for low-dose aspirin compared to placebo. However, this finding was not statistically significant (P=.78).

Researchers found no evidence of increased maternal postpartum hemorrhage with aspirin use.

Among women who received low-dose aspirin, researchers noted a 14% risk reduction for preterm birth (RR=0.86; 95% CI, 0.76-0.98); a 20% risk reduction for IUGR (RR=0.80; 95% CI, 0.65-0.99), and a 24% risk reduction for preeclampsia (RR=0.76; 95% CI, 0.62-0.95). The absolute risk reduction for preeclampsia was estimated to be 2% to 5%.

While the results for preterm birth, IUGR, and preeclampsia were statistically significant, the authors noted that these results could have been biased by small study effects (the tendency of smaller studies to report positive findings, which in turn can skew the results of a meta-analysis based primarily on such studies). The timing and dosage of aspirin had no significant effect on outcomes.

There was no evidence of increased maternal postpartum hemorrhage with aspirin use (RR=1.02; 95% CI, 0.96-1.09). Aspirin use did not seem to increase perinatal mortality among all risk levels (RR=0.92; 95% CI, 0.76-1.11; P=.65). No differences were noted in the toddlers’ development at 18 months.

WHAT'S NEW: Low-dose aspirin use is now recommended

The 1996 USPSTF recommendation concluded that there was insufficient evidence to recommend aspirin use for preventing preeclampsia. This systematic review and meta-analysis, along with findings from a 2007 Cochrane review⁷ and a meta-analysis from the PARIS Collaborative Group,⁸ provide good-quality evidence that aspirin reduces negative maternal and fetal outcomes associated with preeclampsia. In 2014, the USPSTF cited this evidence when it decided to recommend using low-dose aspirin (81 mg/d) to prevent preeclampsia in women who are at high risk for preeclampsia (Grade B).⁹ (For more on the USPSTF, see “Catching up on the latest USPSTF recommendations”.)

CAVEATS: Much of the data came from small studies

A substantial portion of the data in this systematic review and meta-analysis came from small studies with positive findings. Because small studies with null findings tend to not be published, there is concern that the results reported by Henderson et al¹ may be somewhat biased, and that future studies may push the overall observed effect toward a null finding.

Also, the criteria used to define “high risk” for preeclampsia varied by study, so it’s unclear which groups of women would benefit most from aspirin use during pregnancy. Finally, there is a lack of high-quality data on the effects of aspirin use during pregnancy on long-term outcomes in children. Despite these caveats, the cumulative evidence strongly points to greater benefit than harm.

CHALLENGES TO IMPLEMENTATION: You need to determine which patients are at highest risk

The principle challenge lies in identifying which patients are at high risk for preeclampsia, and thus, will likely benefit from this intervention. This systematic review and meta-analysis used a large variety of risk factors to determine whether a woman was high risk. A 2013 American College of Obstetricians and Gynecologists Task Force on Hypertension in Pregnancy report defined high-risk as women with a history of preeclampsia in more than one previous pregnancy or women with a previous preterm delivery due to preeclampsia.⁴

The updated USPSTF recommendation suggests that women be considered high risk if they have any of the following: 1) previous preeclampsia, 2) multifetal gestation, 3) chronic hypertension, 4) diabetes, 5) renal disease, or 6) autoimmune disease.⁹ We consider both sets of criteria reasonable for identifying women who may benefit from low-dose aspirin during pregnancy.

ACKNOWLEDGEMENT
The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.

Illustrative case

A 22-year-old G2P1 pregnant woman at 18 weeks gestation who has a history of preeclampsia comes to your office for a routine prenatal visit. On exam, her blood pressure continues to be in the 110s/60s, as it has been for several visits. Her history puts her at risk of developing preeclampsia again, and you wonder if anything can be done to prevent this from happening.

The incidence of preeclampsia, which occurs in 2% to 8% of pregnancies worldwide and 3.4% of pregnancies in the United States, appears to be steadily increasing.^2,3 Preeclampsia is defined as new-onset hypertension at >20 weeks gestation, plus proteinuria, thrombocytopenia, renal insufficiency, impaired liver function, pulmonary edema, and/or cerebral or visual symptoms.⁴ The condition is associated with several adverse maternal and fetal outcomes, including eclampsia, abruption, intrauterine growth restriction (IUGR), preterm birth, stillbirth, and maternal death.^2,4 Risk factors for preeclampsia include previous preeclampsia, maternal age ≥40 years, chronic medical conditions, and multi-fetal pregnancy.⁵

The only effective treatment for preeclampsia is delivery.⁴ Given the lack of other treatments, strategies for preventing preeclampsia would be highly valuable.

In 1996, the US Preventive Services Task Force (USPSTF) addressed this issue and concluded that there was insufficient evidence to recommend for or against using aspirin to prevent preeclampsia.⁶ More recently, Henderson et al¹ conducted a systematic review and meta-analysis to support the USPSTF in a revision of its earlier recommendation.

STUDY SUMMARY: Aspirin use lowers risk of preeclampsia and preterm birth

Henderson et al¹ evaluated the impact of low-dose aspirin on maternal and fetal outcomes among pregnant women at risk for preeclampsia. The review of 23 studies included 21 randomized placebo-controlled trials that evaluated 24,666 patients. Slightly more than half of the studies that evaluated maternal and fetal health benefits were graded as good-quality, and 67% of those that evaluated maternal, perinatal, and developmental harms were rated good-quality.

Most women were white and ages 20 to 33 years. Aspirin doses ranged from 60 mg/d to 150 mg/d; most studies used 60 mg/d or 100 mg/d. Aspirin was initiated between 12 to 36 weeks gestation, with 9 trials initiating aspirin before 16 weeks. In most trials, aspirin was continued until delivery.

Among women at high preeclampsia risk (10 studies), the pooled relative risk (RR) for perinatal death was 0.81 (95% confidence interval [CI], 0.65-1.01) for low-dose aspirin compared to placebo. However, this finding was not statistically significant (P=.78).

Researchers found no evidence of increased maternal postpartum hemorrhage with aspirin use.

Among women who received low-dose aspirin, researchers noted a 14% risk reduction for preterm birth (RR=0.86; 95% CI, 0.76-0.98); a 20% risk reduction for IUGR (RR=0.80; 95% CI, 0.65-0.99), and a 24% risk reduction for preeclampsia (RR=0.76; 95% CI, 0.62-0.95). The absolute risk reduction for preeclampsia was estimated to be 2% to 5%.

While the results for preterm birth, IUGR, and preeclampsia were statistically significant, the authors noted that these results could have been biased by small study effects (the tendency of smaller studies to report positive findings, which in turn can skew the results of a meta-analysis based primarily on such studies). The timing and dosage of aspirin had no significant effect on outcomes.

There was no evidence of increased maternal postpartum hemorrhage with aspirin use (RR=1.02; 95% CI, 0.96-1.09). Aspirin use did not seem to increase perinatal mortality among all risk levels (RR=0.92; 95% CI, 0.76-1.11; P=.65). No differences were noted in the toddlers’ development at 18 months.

WHAT'S NEW: Low-dose aspirin use is now recommended

The 1996 USPSTF recommendation concluded that there was insufficient evidence to recommend aspirin use for preventing preeclampsia. This systematic review and meta-analysis, along with findings from a 2007 Cochrane review⁷ and a meta-analysis from the PARIS Collaborative Group,⁸ provide good-quality evidence that aspirin reduces negative maternal and fetal outcomes associated with preeclampsia. In 2014, the USPSTF cited this evidence when it decided to recommend using low-dose aspirin (81 mg/d) to prevent preeclampsia in women who are at high risk for preeclampsia (Grade B).⁹ (For more on the USPSTF, see “Catching up on the latest USPSTF recommendations”.)

CAVEATS: Much of the data came from small studies

A substantial portion of the data in this systematic review and meta-analysis came from small studies with positive findings. Because small studies with null findings tend to not be published, there is concern that the results reported by Henderson et al¹ may be somewhat biased, and that future studies may push the overall observed effect toward a null finding.

Also, the criteria used to define “high risk” for preeclampsia varied by study, so it’s unclear which groups of women would benefit most from aspirin use during pregnancy. Finally, there is a lack of high-quality data on the effects of aspirin use during pregnancy on long-term outcomes in children. Despite these caveats, the cumulative evidence strongly points to greater benefit than harm.

CHALLENGES TO IMPLEMENTATION: You need to determine which patients are at highest risk

The principle challenge lies in identifying which patients are at high risk for preeclampsia, and thus, will likely benefit from this intervention. This systematic review and meta-analysis used a large variety of risk factors to determine whether a woman was high risk. A 2013 American College of Obstetricians and Gynecologists Task Force on Hypertension in Pregnancy report defined high-risk as women with a history of preeclampsia in more than one previous pregnancy or women with a previous preterm delivery due to preeclampsia.⁴

The updated USPSTF recommendation suggests that women be considered high risk if they have any of the following: 1) previous preeclampsia, 2) multifetal gestation, 3) chronic hypertension, 4) diabetes, 5) renal disease, or 6) autoimmune disease.⁹ We consider both sets of criteria reasonable for identifying women who may benefit from low-dose aspirin during pregnancy.

ACKNOWLEDGEMENT
The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.

Q) Our radiology department is discussing use of IV magnesium for diabetic patients to “protect them from kidney injury.” Is this a standard of care now?

Magnesium, the fourth most abundant cation in the body, plays an important physiologic role. Balance is maintained by renal regulation of magnesium reabsorption, and deficiency occurs when there is increased renal excretion initiated by osmotic diuresis. Clinical manifestations of deficiency include cardiac arrhythmias, neuromuscular hyperexcitability, and biochemical abnormalities of hypocalcaemia and hypokalemia.

Diabetes is one of the leading causes of magnesium deficiency, with incidence ranging from 25% to 39%.¹ Fluctuations in serum magnesium concentrations are directly correlated with fasting blood glucose, A1C levels, albumin excretion, and the duration of diabetes. It has been postulated that magnesium depletion, via its effect on inositol transport, is pathogenic in the progression of diabetic complications.

Contrast-induced acute kidney injury (CI-AKI) is a potentially adverse consequence of percutaneous coronary interventions (PCI), particularly in diabetic patients. It results in significant morbidity and mortality and adds to the costs of diagnostic and interventional cardiology procedures. Intravenous (IV) agents used during radiologic imaging are notorious for causing acute kidney injury in diabetic patients. Preprocedural hydration and discontinuation of all nephrotoxic medications have proven beneficial in protecting these patients from CI-AKI.

A recent prospective, randomized, open-label clinical trial looked at the effect of administering IV magnesium prior to PCI.² The control group underwent standard preprocedural hydration and discontinuation of nephrotoxic medications. The study group added IV magnesium to the standard protocol.

In this single-center study, 26.6% of patients in the control group and 14.5% in the study group sustained CI-AKI, a statistically significant result (P = .01). Neither group experienced mortality or required dialysis.

Although not considered standard of care at this time, prophylactic use of IV magnesium (pending pre-op labs), along with the recognized benefit of preprocedural hydration and discontinuation of nephrotoxic medications, can be supported in primary PCI patients. Your radiology department is on the cutting edge of protecting these very high-risk patients. 

Debra L. Coplon, DNP, DCC
City of Memphis Wellness Clinic, Tennessee

REFERENCES
1. Ayuk J, Gittoes N. Contemporary view of the clinical relevance of magnesium homeostasis. Ann Clin Biochem. 2014;51(Pt 2):179-188.
2. Firouzi A, Maadani M, Kiani R, et al. Intravenous magnesium sulfate: new method in prevention of contrast-induced nephropathy in primary percutaneous coronary intervention. Int Urol Nephrol. 2015;47(3):521-525.

Q) Our radiology department is discussing use of IV magnesium for diabetic patients to “protect them from kidney injury.” Is this a standard of care now?

Magnesium, the fourth most abundant cation in the body, plays an important physiologic role. Balance is maintained by renal regulation of magnesium reabsorption, and deficiency occurs when there is increased renal excretion initiated by osmotic diuresis. Clinical manifestations of deficiency include cardiac arrhythmias, neuromuscular hyperexcitability, and biochemical abnormalities of hypocalcaemia and hypokalemia.

Diabetes is one of the leading causes of magnesium deficiency, with incidence ranging from 25% to 39%.¹ Fluctuations in serum magnesium concentrations are directly correlated with fasting blood glucose, A1C levels, albumin excretion, and the duration of diabetes. It has been postulated that magnesium depletion, via its effect on inositol transport, is pathogenic in the progression of diabetic complications.

Contrast-induced acute kidney injury (CI-AKI) is a potentially adverse consequence of percutaneous coronary interventions (PCI), particularly in diabetic patients. It results in significant morbidity and mortality and adds to the costs of diagnostic and interventional cardiology procedures. Intravenous (IV) agents used during radiologic imaging are notorious for causing acute kidney injury in diabetic patients. Preprocedural hydration and discontinuation of all nephrotoxic medications have proven beneficial in protecting these patients from CI-AKI.

A recent prospective, randomized, open-label clinical trial looked at the effect of administering IV magnesium prior to PCI.² The control group underwent standard preprocedural hydration and discontinuation of nephrotoxic medications. The study group added IV magnesium to the standard protocol.

In this single-center study, 26.6% of patients in the control group and 14.5% in the study group sustained CI-AKI, a statistically significant result (P = .01). Neither group experienced mortality or required dialysis.

Although not considered standard of care at this time, prophylactic use of IV magnesium (pending pre-op labs), along with the recognized benefit of preprocedural hydration and discontinuation of nephrotoxic medications, can be supported in primary PCI patients. Your radiology department is on the cutting edge of protecting these very high-risk patients. 

Debra L. Coplon, DNP, DCC
City of Memphis Wellness Clinic, Tennessee

REFERENCES
1. Ayuk J, Gittoes N. Contemporary view of the clinical relevance of magnesium homeostasis. Ann Clin Biochem. 2014;51(Pt 2):179-188.
2. Firouzi A, Maadani M, Kiani R, et al. Intravenous magnesium sulfate: new method in prevention of contrast-induced nephropathy in primary percutaneous coronary intervention. Int Urol Nephrol. 2015;47(3):521-525.

Q) Our radiology department is discussing use of IV magnesium for diabetic patients to “protect them from kidney injury.” Is this a standard of care now?

Magnesium, the fourth most abundant cation in the body, plays an important physiologic role. Balance is maintained by renal regulation of magnesium reabsorption, and deficiency occurs when there is increased renal excretion initiated by osmotic diuresis. Clinical manifestations of deficiency include cardiac arrhythmias, neuromuscular hyperexcitability, and biochemical abnormalities of hypocalcaemia and hypokalemia.

Diabetes is one of the leading causes of magnesium deficiency, with incidence ranging from 25% to 39%.¹ Fluctuations in serum magnesium concentrations are directly correlated with fasting blood glucose, A1C levels, albumin excretion, and the duration of diabetes. It has been postulated that magnesium depletion, via its effect on inositol transport, is pathogenic in the progression of diabetic complications.

Contrast-induced acute kidney injury (CI-AKI) is a potentially adverse consequence of percutaneous coronary interventions (PCI), particularly in diabetic patients. It results in significant morbidity and mortality and adds to the costs of diagnostic and interventional cardiology procedures. Intravenous (IV) agents used during radiologic imaging are notorious for causing acute kidney injury in diabetic patients. Preprocedural hydration and discontinuation of all nephrotoxic medications have proven beneficial in protecting these patients from CI-AKI.

A recent prospective, randomized, open-label clinical trial looked at the effect of administering IV magnesium prior to PCI.² The control group underwent standard preprocedural hydration and discontinuation of nephrotoxic medications. The study group added IV magnesium to the standard protocol.

In this single-center study, 26.6% of patients in the control group and 14.5% in the study group sustained CI-AKI, a statistically significant result (P = .01). Neither group experienced mortality or required dialysis.

Although not considered standard of care at this time, prophylactic use of IV magnesium (pending pre-op labs), along with the recognized benefit of preprocedural hydration and discontinuation of nephrotoxic medications, can be supported in primary PCI patients. Your radiology department is on the cutting edge of protecting these very high-risk patients. 

Debra L. Coplon, DNP, DCC
City of Memphis Wellness Clinic, Tennessee

REFERENCES
1. Ayuk J, Gittoes N. Contemporary view of the clinical relevance of magnesium homeostasis. Ann Clin Biochem. 2014;51(Pt 2):179-188.
2. Firouzi A, Maadani M, Kiani R, et al. Intravenous magnesium sulfate: new method in prevention of contrast-induced nephropathy in primary percutaneous coronary intervention. Int Urol Nephrol. 2015;47(3):521-525.

In 2014, the United States Preventive Services Task Force released 24 recommendations on 14 topics.¹ There were no level A recommendations, 10 B recommendations, 1 C recommendation, 3 D recommendations, and 10 I statements. A and B recommendations require that commercial insurance plans offer the recommended services at no cost to patients. This Practice Alert focuses on last year’s B and D recommendations (TABLE 1¹).

Cardiovascular disease

When to screen for abdominal aortic aneurism. The Task Force (TF) reaffirmed a previous B recommendation for a one-time abdominal ultrasound (US) screening for abdominal aortic aneurism (AAA) in men ages 65 to 75 years who have ever smoked. This screening and follow-up of abnormal findings results in decreased AAA rupture and AAA-related mortality, although it appears to have no effect on all-cause mortality.² The value of screening men who have never smoked is very small and should be considered selectively for men who have a family history of AAA, or a personal history of cardiovascular risk factors or disease. The prevalence of AAA in men in the target age group is 6% to 7% (it is 0.8% for women overall in the same age range).²

The recommended screening modality, abdominal US, matches the sensitivity and specificity of abdominal CT but at lower cost and with no radiation exposure. Refer patients with AAAs ≥5.5 cm for surgical repair.²

Patients with smaller aneurysms (3.0 to 5.4 cm) can be managed conservatively with repeated US every 3 to 12 months. Patients with AAAs <3 cm that exhibit rapid growth (>1 cm/year) or that cross the threshold of 5.5 cm on repeated US should undergo surgical consultation.²

The TF also looked at the value of AAA screening for women in the same age group who have ever smoked, and it could not find enough evidence to make a recommendation. However, in women who have never smoked, the TF concluded that, largely due to the low prevalence of AAA, potential harms of screening outweigh its benefits.²

General screening for carotid artery stenosis is unhelpful. For asymptomatic adults, the TF gave a thumbs-down D recommendation on screening for carotid artery stenosis.³ Carotid artery screening is conducted with US, followed by, if findings indicate the need, confirmatory testing with angiography. US has reasonable sensitivity (90%) for finding the most significant lesions, but the specificity of 94% often leads to false-positive results that can bring about unnecessary surgery and serious harms, including death, stroke, and myocardial infarction. There is no evidence of any benefit from screening by auscultation of the neck.

The TF believes it is better to focus on primary prevention of stroke, including screening for hypertension and dyslipidemia, counseling on smoking cessation, encouraging healthful diet and physical activity, and recommending aspirin use for those at increased risk for cardiovascular disease.³

Focus on CVD prevention. For adults who are overweight or obese and have additional cardiovascular disease (CVD) risk factors, the TF recommends offering, or referring patients for, intensive behavioral counseling interventions to promote a healthy diet and increased physical activity. A previous Practice Alert discussed the rationale behind this selective intensive approach to CVD prevention, as well as the lack of endorsement of vitamins to prevent CVD or cancer.⁴

Sexually transmitted infections

When to screen for gonorrhea and chlamydia. The TF recommends screening for chlamydial and gonorrheal infections in all sexually active women ages 24 years and younger, and for women older than 24 years who are at high risk.⁵ The TF could not find adequate evidence to make a recommendation for or against screening men for either disease.

The USPSTF recommends screening for chlamydial and gonorrheal infections in all sexually active women ages 24 years and younger.

Risk is defined rather broadly to include having a new sex partner, more than one sex partner, or a sex partner with concurrent partners or a sexually transmitted infection (STI); inconsistent condom use among individuals who are not in mutually monogamous relationships; having a previous or coexisting STI; and exchanging sex for money or drugs. The TF also points out that physicians should know the prevalence of these infections in their community and be aware of particular groups that are at higher risk.

Chlamydia and gonorrhea are the most commonly reported STIs in the United States. In 2012, more than 1.4 million cases of chlamydial infection were reported to the Centers for Disease Control and Prevention (CDC).⁵ This is an underestimate of true prevalence because most infections are asymptomatic and not detected. The rate of chlamydial infection in females was 643.3 cases per 100,000 (more than twice that seen in males—262.6 cases per 100,000), with most infections occurring in females ages 15 to 24 years.⁵

In 2012, more than 330,000 cases of gonococcal infection were reported to the CDC. The rate of gonorrhea infection was similar for females and males (108.7 vs. 105.8 cases per 100,000, respectively), but while most infections in females occurred between the ages of 15 and 24 years, men most often affected were ages 20 to 24 years.⁵

Chlamydial and gonococcal infections can be diagnosed by nucleic acid amplification tests conducted on specimens collected in a number of ways: urine; endocervical, vaginal, and male urethral specimens; and self-collected vaginal specimens in clinical settings. Treatment recommendations for both infections can be found on the CDC STI treatment Web site.⁶

Intensive behavioral counseling as a means of preventing STIs is recommended for all sexually active adolescents and adults at elevated risk—ie, those with current STIs or infected within the past year, those who have multiple sex partners, and those who do not consistently use condoms.⁷

In a change of its previous position, the USPSTF now recommends screening for hepatitis B virus in those at high risk.

Intensive intervention ranges from 30 minutes to 2 hours or more of contact time. All counseling within this range is beneficial, with more time being more effective.⁷ These interventions can be delivered by primary care clinicians or behavioral counselors. The most successful approaches provide basic information about STIs (and STI transmission) and train patients in important skills, such as condom use, communication about safe sex, problem solving, and goal setting.

Hepatitis B screening: A change

The TF changed its previous position on screening for chronic hepatitis B virus (HBV) in those at high risk from an I statement to a B recommendation. Previously, the TF opposed screening of low-risk populations; the new recommendation is silent on this issue. Those at high risk for HBV include:⁸
• individuals born in countries and regions with a prevalence of HBV infection ≥2%
• US-born individuals not vaccinated as infants, whose parents are from regions with a very high prevalence of HBV infection (≥8%)—eg, sub-Saharan Africa or southeast or central Asia
• HIV-positive individuals
• injection drug users
• men who have sex with men
• household contacts or sexual partners of individuals with HBV infection.

Information on countries and regions with a high prevalence of HBV infection can be found at: www.cdc.gov/mmwr/preview/mmwrhtml/rr5708a1.htm.

The TF notes that approximately 700,000 to 2.2 million individuals in the United States have chronic HBV infection.⁸ However, HBV vaccine has been a recommended child vaccine for more than 20 years and the pool of those at risk shrinks annually.

Chronic HBV infection can lead to cirrhosis, hepatic failure, and hepatocellular carcinoma. An estimated 15% to 25% of individuals with chronic HBV infection die of cirrhosis or hepatocellular carcinoma.⁸ Those with chronic infection can also infect others. Screening for HBV infection could identify chronically infected people who may benefit from treatment and be counseled to prevent transmission.

In a new recommendation, the USPSTF endorses low-dose aspirin (81 mg/d) to reduce rates of preeclampsia in women at increased risk.

In screening, test for hepatitis B surface antigen (HBsAg), which has a reported sensitivity and specificity of >98%.⁸ While the TF did not find direct evidence of screening benefits on mortality, it found convincing evidence that antiviral treatment in patients with chronic HBV infection improves intermediate outcomes (virologic or histologic improvement or clearance of hepatitis B e antigen [HBeAg]) and adequate evidence that antiviral regimens improve health outcomes (such as reduced risk for hepatocellular carcinoma).⁸

Prevention of tooth decay in kids

The TF recommends that primary care physicians implement 2 interventions to prevent tooth decay in infants and children: prescribing oral fluoride supplementation starting at age 6 months in areas where the local water supply is deficient in fluoride (defined as <0.6 ppm F); and periodically applying fluoride varnish to primary teeth starting at the age of tooth eruption through age 5 years. The TF emphasizes, however, that the most effective way to prevent dental decay in children is to maintain recommended levels of fluoride in community water supplies.⁹

Both recommended interventions are supported by good evidence, although no study directly assessed the appropriate ages at which to start and stop the application of fluoride varnish or the optimal frequency of applications. Most studies looked at children ages 3 to 5 years, but the TF believes that benefits are likely to begin at the time of primary tooth eruption.

Limited evidence found no clear difference in benefit between performing a single fluoride varnish once every 6 months vs once a year or between a single application every 6 months vs multiple applications once a year or every 6 months.⁹

Pregnancy

Screen for gestational diabetes. The previous TF statement on gestational diabetes mellitus (GDM) found insufficient evidence to screen for this condition. The new recommendation advises screening starting at 24 weeks gestation using the 50-g oral glucose challenge test.¹⁰ Other screening options, such as the use of fasting plasma glucose testing or basing decisions to screen on risk factors, have not been studied as extensively. The USPSTF found inadequate evidence to compare the effectiveness of different screening tests or thresholds in determining positive screen results.

Treating those with GDM with diet, glucose monitoring, and insulin (if needed) can significantly reduce the risk of preeclampsia, fetal macrosomia, and shoulder dystocia, which, according to the TF, adds up to a moderate net benefit for both mother and infant. There is no evidence that treatment will improve long-term metabolic outcomes in women.

The TF found inadequate evidence to determine whether there are benefits to screening for GDM in women before 24 weeks of gestation.

Give low-dose aspirin to prevent preeclampsia. In a new recommendation, the TF endorses low-dose aspirin (81 mg/d) to reduce rates of preeclampsia, preterm birth, and intrauterine growth restriction (IUGR) in women at increased risk for preeclampsia—defined as those with kidney disease, diabetes (type 1 or 2), hypertension, autoimmune disease, a history of preeclampsia, or a current multifetal pregnancy.¹¹

Aspirin should be started after 12 weeks and before 28 weeks of gestation, which has been shown to reduce the risk of preeclampsia by 24%, preterm birth by 14%, and IUGR by 20%.¹¹ The number needed to treat to prevent one case of preeclampsia was 42; 71 for IUGR, and 65 for preterm birth.¹¹ (For more on the evidence behind this recommendation, see “Another good reason to recommend lowdose aspirin” on page 301.)

TABLE 2¹¹ lists risk factors for preeclampsia and recommendations for those in high-, moderate-, and low-risk groups.

Screenings/interventions with insufficient supporting evidence

Three conditions that cause significant morbidity or mortality were looked at by the TF last year, and insufficient evidence was found to make a recommendation—screening for cognitive impairment (early Alzheimer’s); primary care interventions to prevent or reduce illicit drug or nonmedical pharmaceutical use in children and adolescents; and screening for suicide risk in adolescents, adults, and older adults in primary care. In addition, no evidence could be found for the benefit of screening for vitamin D deficiency in adults.

In 2014, the United States Preventive Services Task Force released 24 recommendations on 14 topics.¹ There were no level A recommendations, 10 B recommendations, 1 C recommendation, 3 D recommendations, and 10 I statements. A and B recommendations require that commercial insurance plans offer the recommended services at no cost to patients. This Practice Alert focuses on last year’s B and D recommendations (TABLE 1¹).

Cardiovascular disease

When to screen for abdominal aortic aneurism. The Task Force (TF) reaffirmed a previous B recommendation for a one-time abdominal ultrasound (US) screening for abdominal aortic aneurism (AAA) in men ages 65 to 75 years who have ever smoked. This screening and follow-up of abnormal findings results in decreased AAA rupture and AAA-related mortality, although it appears to have no effect on all-cause mortality.² The value of screening men who have never smoked is very small and should be considered selectively for men who have a family history of AAA, or a personal history of cardiovascular risk factors or disease. The prevalence of AAA in men in the target age group is 6% to 7% (it is 0.8% for women overall in the same age range).²

The recommended screening modality, abdominal US, matches the sensitivity and specificity of abdominal CT but at lower cost and with no radiation exposure. Refer patients with AAAs ≥5.5 cm for surgical repair.²

Patients with smaller aneurysms (3.0 to 5.4 cm) can be managed conservatively with repeated US every 3 to 12 months. Patients with AAAs <3 cm that exhibit rapid growth (>1 cm/year) or that cross the threshold of 5.5 cm on repeated US should undergo surgical consultation.²

The TF also looked at the value of AAA screening for women in the same age group who have ever smoked, and it could not find enough evidence to make a recommendation. However, in women who have never smoked, the TF concluded that, largely due to the low prevalence of AAA, potential harms of screening outweigh its benefits.²

General screening for carotid artery stenosis is unhelpful. For asymptomatic adults, the TF gave a thumbs-down D recommendation on screening for carotid artery stenosis.³ Carotid artery screening is conducted with US, followed by, if findings indicate the need, confirmatory testing with angiography. US has reasonable sensitivity (90%) for finding the most significant lesions, but the specificity of 94% often leads to false-positive results that can bring about unnecessary surgery and serious harms, including death, stroke, and myocardial infarction. There is no evidence of any benefit from screening by auscultation of the neck.

The TF believes it is better to focus on primary prevention of stroke, including screening for hypertension and dyslipidemia, counseling on smoking cessation, encouraging healthful diet and physical activity, and recommending aspirin use for those at increased risk for cardiovascular disease.³

Focus on CVD prevention. For adults who are overweight or obese and have additional cardiovascular disease (CVD) risk factors, the TF recommends offering, or referring patients for, intensive behavioral counseling interventions to promote a healthy diet and increased physical activity. A previous Practice Alert discussed the rationale behind this selective intensive approach to CVD prevention, as well as the lack of endorsement of vitamins to prevent CVD or cancer.⁴

Sexually transmitted infections

When to screen for gonorrhea and chlamydia. The TF recommends screening for chlamydial and gonorrheal infections in all sexually active women ages 24 years and younger, and for women older than 24 years who are at high risk.⁵ The TF could not find adequate evidence to make a recommendation for or against screening men for either disease.

The USPSTF recommends screening for chlamydial and gonorrheal infections in all sexually active women ages 24 years and younger.

Risk is defined rather broadly to include having a new sex partner, more than one sex partner, or a sex partner with concurrent partners or a sexually transmitted infection (STI); inconsistent condom use among individuals who are not in mutually monogamous relationships; having a previous or coexisting STI; and exchanging sex for money or drugs. The TF also points out that physicians should know the prevalence of these infections in their community and be aware of particular groups that are at higher risk.

Chlamydia and gonorrhea are the most commonly reported STIs in the United States. In 2012, more than 1.4 million cases of chlamydial infection were reported to the Centers for Disease Control and Prevention (CDC).⁵ This is an underestimate of true prevalence because most infections are asymptomatic and not detected. The rate of chlamydial infection in females was 643.3 cases per 100,000 (more than twice that seen in males—262.6 cases per 100,000), with most infections occurring in females ages 15 to 24 years.⁵

In 2012, more than 330,000 cases of gonococcal infection were reported to the CDC. The rate of gonorrhea infection was similar for females and males (108.7 vs. 105.8 cases per 100,000, respectively), but while most infections in females occurred between the ages of 15 and 24 years, men most often affected were ages 20 to 24 years.⁵

Chlamydial and gonococcal infections can be diagnosed by nucleic acid amplification tests conducted on specimens collected in a number of ways: urine; endocervical, vaginal, and male urethral specimens; and self-collected vaginal specimens in clinical settings. Treatment recommendations for both infections can be found on the CDC STI treatment Web site.⁶

Intensive behavioral counseling as a means of preventing STIs is recommended for all sexually active adolescents and adults at elevated risk—ie, those with current STIs or infected within the past year, those who have multiple sex partners, and those who do not consistently use condoms.⁷

In a change of its previous position, the USPSTF now recommends screening for hepatitis B virus in those at high risk.

Intensive intervention ranges from 30 minutes to 2 hours or more of contact time. All counseling within this range is beneficial, with more time being more effective.⁷ These interventions can be delivered by primary care clinicians or behavioral counselors. The most successful approaches provide basic information about STIs (and STI transmission) and train patients in important skills, such as condom use, communication about safe sex, problem solving, and goal setting.

Hepatitis B screening: A change

The TF changed its previous position on screening for chronic hepatitis B virus (HBV) in those at high risk from an I statement to a B recommendation. Previously, the TF opposed screening of low-risk populations; the new recommendation is silent on this issue. Those at high risk for HBV include:⁸
• individuals born in countries and regions with a prevalence of HBV infection ≥2%
• US-born individuals not vaccinated as infants, whose parents are from regions with a very high prevalence of HBV infection (≥8%)—eg, sub-Saharan Africa or southeast or central Asia
• HIV-positive individuals
• injection drug users
• men who have sex with men
• household contacts or sexual partners of individuals with HBV infection.

Information on countries and regions with a high prevalence of HBV infection can be found at: www.cdc.gov/mmwr/preview/mmwrhtml/rr5708a1.htm.

The TF notes that approximately 700,000 to 2.2 million individuals in the United States have chronic HBV infection.⁸ However, HBV vaccine has been a recommended child vaccine for more than 20 years and the pool of those at risk shrinks annually.

Chronic HBV infection can lead to cirrhosis, hepatic failure, and hepatocellular carcinoma. An estimated 15% to 25% of individuals with chronic HBV infection die of cirrhosis or hepatocellular carcinoma.⁸ Those with chronic infection can also infect others. Screening for HBV infection could identify chronically infected people who may benefit from treatment and be counseled to prevent transmission.

In a new recommendation, the USPSTF endorses low-dose aspirin (81 mg/d) to reduce rates of preeclampsia in women at increased risk.

In screening, test for hepatitis B surface antigen (HBsAg), which has a reported sensitivity and specificity of >98%.⁸ While the TF did not find direct evidence of screening benefits on mortality, it found convincing evidence that antiviral treatment in patients with chronic HBV infection improves intermediate outcomes (virologic or histologic improvement or clearance of hepatitis B e antigen [HBeAg]) and adequate evidence that antiviral regimens improve health outcomes (such as reduced risk for hepatocellular carcinoma).⁸

Prevention of tooth decay in kids

The TF recommends that primary care physicians implement 2 interventions to prevent tooth decay in infants and children: prescribing oral fluoride supplementation starting at age 6 months in areas where the local water supply is deficient in fluoride (defined as <0.6 ppm F); and periodically applying fluoride varnish to primary teeth starting at the age of tooth eruption through age 5 years. The TF emphasizes, however, that the most effective way to prevent dental decay in children is to maintain recommended levels of fluoride in community water supplies.⁹

Both recommended interventions are supported by good evidence, although no study directly assessed the appropriate ages at which to start and stop the application of fluoride varnish or the optimal frequency of applications. Most studies looked at children ages 3 to 5 years, but the TF believes that benefits are likely to begin at the time of primary tooth eruption.

Limited evidence found no clear difference in benefit between performing a single fluoride varnish once every 6 months vs once a year or between a single application every 6 months vs multiple applications once a year or every 6 months.⁹

Pregnancy

Screen for gestational diabetes. The previous TF statement on gestational diabetes mellitus (GDM) found insufficient evidence to screen for this condition. The new recommendation advises screening starting at 24 weeks gestation using the 50-g oral glucose challenge test.¹⁰ Other screening options, such as the use of fasting plasma glucose testing or basing decisions to screen on risk factors, have not been studied as extensively. The USPSTF found inadequate evidence to compare the effectiveness of different screening tests or thresholds in determining positive screen results.

Treating those with GDM with diet, glucose monitoring, and insulin (if needed) can significantly reduce the risk of preeclampsia, fetal macrosomia, and shoulder dystocia, which, according to the TF, adds up to a moderate net benefit for both mother and infant. There is no evidence that treatment will improve long-term metabolic outcomes in women.

The TF found inadequate evidence to determine whether there are benefits to screening for GDM in women before 24 weeks of gestation.

Give low-dose aspirin to prevent preeclampsia. In a new recommendation, the TF endorses low-dose aspirin (81 mg/d) to reduce rates of preeclampsia, preterm birth, and intrauterine growth restriction (IUGR) in women at increased risk for preeclampsia—defined as those with kidney disease, diabetes (type 1 or 2), hypertension, autoimmune disease, a history of preeclampsia, or a current multifetal pregnancy.¹¹

Aspirin should be started after 12 weeks and before 28 weeks of gestation, which has been shown to reduce the risk of preeclampsia by 24%, preterm birth by 14%, and IUGR by 20%.¹¹ The number needed to treat to prevent one case of preeclampsia was 42; 71 for IUGR, and 65 for preterm birth.¹¹ (For more on the evidence behind this recommendation, see “Another good reason to recommend lowdose aspirin” on page 301.)

TABLE 2¹¹ lists risk factors for preeclampsia and recommendations for those in high-, moderate-, and low-risk groups.

Screenings/interventions with insufficient supporting evidence

Three conditions that cause significant morbidity or mortality were looked at by the TF last year, and insufficient evidence was found to make a recommendation—screening for cognitive impairment (early Alzheimer’s); primary care interventions to prevent or reduce illicit drug or nonmedical pharmaceutical use in children and adolescents; and screening for suicide risk in adolescents, adults, and older adults in primary care. In addition, no evidence could be found for the benefit of screening for vitamin D deficiency in adults.

In 2014, the United States Preventive Services Task Force released 24 recommendations on 14 topics.¹ There were no level A recommendations, 10 B recommendations, 1 C recommendation, 3 D recommendations, and 10 I statements. A and B recommendations require that commercial insurance plans offer the recommended services at no cost to patients. This Practice Alert focuses on last year’s B and D recommendations (TABLE 1¹).

Cardiovascular disease

When to screen for abdominal aortic aneurism. The Task Force (TF) reaffirmed a previous B recommendation for a one-time abdominal ultrasound (US) screening for abdominal aortic aneurism (AAA) in men ages 65 to 75 years who have ever smoked. This screening and follow-up of abnormal findings results in decreased AAA rupture and AAA-related mortality, although it appears to have no effect on all-cause mortality.² The value of screening men who have never smoked is very small and should be considered selectively for men who have a family history of AAA, or a personal history of cardiovascular risk factors or disease. The prevalence of AAA in men in the target age group is 6% to 7% (it is 0.8% for women overall in the same age range).²

The recommended screening modality, abdominal US, matches the sensitivity and specificity of abdominal CT but at lower cost and with no radiation exposure. Refer patients with AAAs ≥5.5 cm for surgical repair.²

Patients with smaller aneurysms (3.0 to 5.4 cm) can be managed conservatively with repeated US every 3 to 12 months. Patients with AAAs <3 cm that exhibit rapid growth (>1 cm/year) or that cross the threshold of 5.5 cm on repeated US should undergo surgical consultation.²

The TF also looked at the value of AAA screening for women in the same age group who have ever smoked, and it could not find enough evidence to make a recommendation. However, in women who have never smoked, the TF concluded that, largely due to the low prevalence of AAA, potential harms of screening outweigh its benefits.²

General screening for carotid artery stenosis is unhelpful. For asymptomatic adults, the TF gave a thumbs-down D recommendation on screening for carotid artery stenosis.³ Carotid artery screening is conducted with US, followed by, if findings indicate the need, confirmatory testing with angiography. US has reasonable sensitivity (90%) for finding the most significant lesions, but the specificity of 94% often leads to false-positive results that can bring about unnecessary surgery and serious harms, including death, stroke, and myocardial infarction. There is no evidence of any benefit from screening by auscultation of the neck.

The TF believes it is better to focus on primary prevention of stroke, including screening for hypertension and dyslipidemia, counseling on smoking cessation, encouraging healthful diet and physical activity, and recommending aspirin use for those at increased risk for cardiovascular disease.³

Focus on CVD prevention. For adults who are overweight or obese and have additional cardiovascular disease (CVD) risk factors, the TF recommends offering, or referring patients for, intensive behavioral counseling interventions to promote a healthy diet and increased physical activity. A previous Practice Alert discussed the rationale behind this selective intensive approach to CVD prevention, as well as the lack of endorsement of vitamins to prevent CVD or cancer.⁴

Sexually transmitted infections

When to screen for gonorrhea and chlamydia. The TF recommends screening for chlamydial and gonorrheal infections in all sexually active women ages 24 years and younger, and for women older than 24 years who are at high risk.⁵ The TF could not find adequate evidence to make a recommendation for or against screening men for either disease.

The USPSTF recommends screening for chlamydial and gonorrheal infections in all sexually active women ages 24 years and younger.

Risk is defined rather broadly to include having a new sex partner, more than one sex partner, or a sex partner with concurrent partners or a sexually transmitted infection (STI); inconsistent condom use among individuals who are not in mutually monogamous relationships; having a previous or coexisting STI; and exchanging sex for money or drugs. The TF also points out that physicians should know the prevalence of these infections in their community and be aware of particular groups that are at higher risk.

Chlamydia and gonorrhea are the most commonly reported STIs in the United States. In 2012, more than 1.4 million cases of chlamydial infection were reported to the Centers for Disease Control and Prevention (CDC).⁵ This is an underestimate of true prevalence because most infections are asymptomatic and not detected. The rate of chlamydial infection in females was 643.3 cases per 100,000 (more than twice that seen in males—262.6 cases per 100,000), with most infections occurring in females ages 15 to 24 years.⁵

In 2012, more than 330,000 cases of gonococcal infection were reported to the CDC. The rate of gonorrhea infection was similar for females and males (108.7 vs. 105.8 cases per 100,000, respectively), but while most infections in females occurred between the ages of 15 and 24 years, men most often affected were ages 20 to 24 years.⁵

Chlamydial and gonococcal infections can be diagnosed by nucleic acid amplification tests conducted on specimens collected in a number of ways: urine; endocervical, vaginal, and male urethral specimens; and self-collected vaginal specimens in clinical settings. Treatment recommendations for both infections can be found on the CDC STI treatment Web site.⁶

Intensive behavioral counseling as a means of preventing STIs is recommended for all sexually active adolescents and adults at elevated risk—ie, those with current STIs or infected within the past year, those who have multiple sex partners, and those who do not consistently use condoms.⁷

In a change of its previous position, the USPSTF now recommends screening for hepatitis B virus in those at high risk.

Intensive intervention ranges from 30 minutes to 2 hours or more of contact time. All counseling within this range is beneficial, with more time being more effective.⁷ These interventions can be delivered by primary care clinicians or behavioral counselors. The most successful approaches provide basic information about STIs (and STI transmission) and train patients in important skills, such as condom use, communication about safe sex, problem solving, and goal setting.

Hepatitis B screening: A change

The TF changed its previous position on screening for chronic hepatitis B virus (HBV) in those at high risk from an I statement to a B recommendation. Previously, the TF opposed screening of low-risk populations; the new recommendation is silent on this issue. Those at high risk for HBV include:⁸
• individuals born in countries and regions with a prevalence of HBV infection ≥2%
• US-born individuals not vaccinated as infants, whose parents are from regions with a very high prevalence of HBV infection (≥8%)—eg, sub-Saharan Africa or southeast or central Asia
• HIV-positive individuals
• injection drug users
• men who have sex with men
• household contacts or sexual partners of individuals with HBV infection.

Information on countries and regions with a high prevalence of HBV infection can be found at: www.cdc.gov/mmwr/preview/mmwrhtml/rr5708a1.htm.

The TF notes that approximately 700,000 to 2.2 million individuals in the United States have chronic HBV infection.⁸ However, HBV vaccine has been a recommended child vaccine for more than 20 years and the pool of those at risk shrinks annually.

Chronic HBV infection can lead to cirrhosis, hepatic failure, and hepatocellular carcinoma. An estimated 15% to 25% of individuals with chronic HBV infection die of cirrhosis or hepatocellular carcinoma.⁸ Those with chronic infection can also infect others. Screening for HBV infection could identify chronically infected people who may benefit from treatment and be counseled to prevent transmission.

In a new recommendation, the USPSTF endorses low-dose aspirin (81 mg/d) to reduce rates of preeclampsia in women at increased risk.

In screening, test for hepatitis B surface antigen (HBsAg), which has a reported sensitivity and specificity of >98%.⁸ While the TF did not find direct evidence of screening benefits on mortality, it found convincing evidence that antiviral treatment in patients with chronic HBV infection improves intermediate outcomes (virologic or histologic improvement or clearance of hepatitis B e antigen [HBeAg]) and adequate evidence that antiviral regimens improve health outcomes (such as reduced risk for hepatocellular carcinoma).⁸

Prevention of tooth decay in kids

The TF recommends that primary care physicians implement 2 interventions to prevent tooth decay in infants and children: prescribing oral fluoride supplementation starting at age 6 months in areas where the local water supply is deficient in fluoride (defined as <0.6 ppm F); and periodically applying fluoride varnish to primary teeth starting at the age of tooth eruption through age 5 years. The TF emphasizes, however, that the most effective way to prevent dental decay in children is to maintain recommended levels of fluoride in community water supplies.⁹

Both recommended interventions are supported by good evidence, although no study directly assessed the appropriate ages at which to start and stop the application of fluoride varnish or the optimal frequency of applications. Most studies looked at children ages 3 to 5 years, but the TF believes that benefits are likely to begin at the time of primary tooth eruption.

Limited evidence found no clear difference in benefit between performing a single fluoride varnish once every 6 months vs once a year or between a single application every 6 months vs multiple applications once a year or every 6 months.⁹

Pregnancy

Screen for gestational diabetes. The previous TF statement on gestational diabetes mellitus (GDM) found insufficient evidence to screen for this condition. The new recommendation advises screening starting at 24 weeks gestation using the 50-g oral glucose challenge test.¹⁰ Other screening options, such as the use of fasting plasma glucose testing or basing decisions to screen on risk factors, have not been studied as extensively. The USPSTF found inadequate evidence to compare the effectiveness of different screening tests or thresholds in determining positive screen results.

Treating those with GDM with diet, glucose monitoring, and insulin (if needed) can significantly reduce the risk of preeclampsia, fetal macrosomia, and shoulder dystocia, which, according to the TF, adds up to a moderate net benefit for both mother and infant. There is no evidence that treatment will improve long-term metabolic outcomes in women.

The TF found inadequate evidence to determine whether there are benefits to screening for GDM in women before 24 weeks of gestation.

Give low-dose aspirin to prevent preeclampsia. In a new recommendation, the TF endorses low-dose aspirin (81 mg/d) to reduce rates of preeclampsia, preterm birth, and intrauterine growth restriction (IUGR) in women at increased risk for preeclampsia—defined as those with kidney disease, diabetes (type 1 or 2), hypertension, autoimmune disease, a history of preeclampsia, or a current multifetal pregnancy.¹¹

Aspirin should be started after 12 weeks and before 28 weeks of gestation, which has been shown to reduce the risk of preeclampsia by 24%, preterm birth by 14%, and IUGR by 20%.¹¹ The number needed to treat to prevent one case of preeclampsia was 42; 71 for IUGR, and 65 for preterm birth.¹¹ (For more on the evidence behind this recommendation, see “Another good reason to recommend lowdose aspirin” on page 301.)

TABLE 2¹¹ lists risk factors for preeclampsia and recommendations for those in high-, moderate-, and low-risk groups.

Screenings/interventions with insufficient supporting evidence

Three conditions that cause significant morbidity or mortality were looked at by the TF last year, and insufficient evidence was found to make a recommendation—screening for cognitive impairment (early Alzheimer’s); primary care interventions to prevent or reduce illicit drug or nonmedical pharmaceutical use in children and adolescents; and screening for suicide risk in adolescents, adults, and older adults in primary care. In addition, no evidence could be found for the benefit of screening for vitamin D deficiency in adults.

Edited by: Arthur T. Skarin, MD, FACP, FCCP

Epithelial ovarian cancer is the fifth leading cause of cancer death among women in the United States. Most women with ovarian cancer present at an advanced stage (International Federation of Gynecology and Obstetrics stage III), for which the standard treatment remains cytoreductive surgery followed by platinum- and taxane-based combination chemotherapy. Although this treatment frequently is curative for patients with early-stage disease, more than 60% of women with advanced disease will develop recurrent disease with progressively shorter disease-free intervals. However, there are many clinical trials in progress that are aimed at refining current therapy and evaluating different approaches to postoperative therapy, with the goal of improving prognosis and quality of life.

To read the full article in PDF:

Click here

Edited by: Arthur T. Skarin, MD, FACP, FCCP

Epithelial ovarian cancer is the fifth leading cause of cancer death among women in the United States. Most women with ovarian cancer present at an advanced stage (International Federation of Gynecology and Obstetrics stage III), for which the standard treatment remains cytoreductive surgery followed by platinum- and taxane-based combination chemotherapy. Although this treatment frequently is curative for patients with early-stage disease, more than 60% of women with advanced disease will develop recurrent disease with progressively shorter disease-free intervals. However, there are many clinical trials in progress that are aimed at refining current therapy and evaluating different approaches to postoperative therapy, with the goal of improving prognosis and quality of life.

To read the full article in PDF:

Click here

Edited by: Arthur T. Skarin, MD, FACP, FCCP

Epithelial ovarian cancer is the fifth leading cause of cancer death among women in the United States. Most women with ovarian cancer present at an advanced stage (International Federation of Gynecology and Obstetrics stage III), for which the standard treatment remains cytoreductive surgery followed by platinum- and taxane-based combination chemotherapy. Although this treatment frequently is curative for patients with early-stage disease, more than 60% of women with advanced disease will develop recurrent disease with progressively shorter disease-free intervals. However, there are many clinical trials in progress that are aimed at refining current therapy and evaluating different approaches to postoperative therapy, with the goal of improving prognosis and quality of life.

To read the full article in PDF:

Click here

Case

An 8-month-old boy with a history of hypotonia, developmental delay, and seizure disorder refractory to multiple anticonvulsant medications, was presented to the ED with a 2-week history of intermittent fever and poor oral intake. His current medications included sodium bromide 185 mg orally twice daily for his seizure disorder.

On physical examination, the boy appeared small for his age, with diffuse hypotonia and diminished reflexes. He was able to track with his eyes but was otherwise unresponsive. No rash was present. Results of initial laboratory studies were: sodium 144 mEq/L; potassium, 4.8 mEq/L; chloride, 179 mEq/L; bicarbonate, 21 mEq/L; blood urea nitrogen, 6 mg/dL; creatinine, 0.1 mg/dL; and glucose, 63 mg/dL. His anion gap (AG) was −56.

What does the anion gap represent?

The AG is a valuable clinical calculation derived from the measured extracellular electrolytes and provides an index of acid-base status.¹ Due to the necessity of electroneutrality, the sum of positive charges (cations) in the extracellular fluid must be balanced exactly with the sum of negative charges (anions). However, to routinely measure all of the cations and anions in the serum would be time-consuming and is also unnecessary. Because most clinical laboratories commonly only measure one relevant cation (sodium) and two anions (chloride and bicarbonate), the positive and negative sums are not completely balanced. The AG therefore refers to this difference (ie, AG = Na – [Cl + HCO₃]).

Of course, electroneutrality exists in vivo, and is accomplished by the presence of unmeasured anions (UA) (eg, lactate and phosphate) and unmeasured cations (UC) (eg, potassium and calcium) not accounted for in the AG (ie, AG = UA – UC). In other words, the sum of measured plus the unmeasured anions must equal the sum of the measured plus unmeasured cations.

What causes a low or negative anion gap?

While most healthcare providers are well versed in the clinical significance of an elevated AG (eg, MUDPILES [methanol, uremia, diabetic ketoacidosis, propylene glycol or phenformin, iron or isoniazid, lactate, ethylene glycol, salicylates]), the meaning of a low or negative AG is underappreciated. There are several scenarios that could potentially yield a low or negative AG, including decreased concentration of UA, increased concentrations of nonsodium cations (UC), and overestimation of serum chloride.

Decreased Concentration of Unmeasured Anions. This most commonly occurs by two mechanisms: dilution of the extracellular fluid or hypoalbuminemia. The addition of water to the extracellular fluid will cause a proportionate dilution of all the measured electrolytes. Since the concentration of measured cations is higher than the measured anions, there is a small and relatively insignificant decrease in the AG.

Alternatively, hypoalbuminemia results in a low AG due to the change in UA; albumin is negatively charged. At physiologic pH, the overwhelming majority of serum proteins are anionic and counter-balanced by the positive charge of sodium. Albumin, the most abundant serum protein, accounts for approximately 75% of the normal AG. Hypoalbuminemic states, such as cirrhosis or nephrotic syndrome, can therefore cause low AG due to the retention of chloride to replace the lost negative charge. The albumin concentration can be corrected to calculate the AG.²

Nonsodium Cations. There are a number of clinical conditions that result in the retention of nonsodium cations. For example, the excess positively charged paraproteins associated with IgG myeloma raise the UC concentration, resulting in a low AG. Similarly, elevations of unmeasured cationic electrolytes, such as calcium and magnesium, may also result in a lower AG. Significant changes in AG, though, are caused only by profound (and often life-threatening) hypercalcemia or hypermagnesemia.

Overestimation of Serum Chloride. Overestimation of serum chloride most commonly occurs in the clinical scenario of bromide exposure. In normal physiologic conditions, chloride is the only halide present in the extracellular fluid. With intake of brominated products, chloride may be partially replaced by bromide. As there is greater renal tubular avidity for bromide, chronic ingestion of bromide results in a gradual rise in serum bromide concentrations with a proportional fall in chloride. However, and more importantly, bromide interferes with a number of laboratory techniques measuring chloride concentrations, resulting in a spuriously elevated chloride, or pseudohyperchloremia. Because the measured sodium and bicarbonate concentrations will remain unchanged, this falsely elevated chloride measurement will result in a negative AG.

What causes the falsely elevated chloride?

All of the current laboratory techniques for measurement of serum chloride concentration can potentially result in a falsely elevated value. However, the degree of pseudohyperchloremia will depend on the specific assay used for measurement. The ion-selective electrode method used by many common laboratory analyzers appears to have the greatest interference on chloride measurement in the presence of bromide. This is simply due to the molecular similarity of bromide and chloride. Conversely, the coulometry method, often used as a reference standard, has the least interference of current laboratory methods.³ This is because coulometry does not completely rely on molecular structure to measure concentration, but rather it measures the amount of energy produced or consumed in an electrolysis reaction. Iodide, another halide compound, has also been described as a cause of pseudohyperchloremia, whereas fluoride does not seem to have significant interference.⁴ 

How are patients exposed to bromide salts?

Bromide salts, specifically sodium bromide, are infrequently used to treat seizure disorders, but are generally reserved for patients with epilepsy refractory to other, less toxic anticonvulsant medications. During the era when bromide salts were more commonly used to treat epilepsy, bromide intoxication, or bromism, was frequently observed.

Bromism may manifest as a constellation of nonspecific neurological and psychiatric symptoms. These most commonly include headache, weakness, agitation, confusion, and hallucinations. In more severe cases of bromism, stupor and coma may occur.^3,5

Although bromide salts are no longer commonly prescribed, a number of products still contain brominated ingredients. Symptoms of bromide intoxication can occur with chronic use of a cough syrup containing dextromethorphan hydrobromide as well as the brominated vegetable oils found in some soft drinks.⁵ 

How is bromism treated?

The treatment of bromism involves preventing further exposure to bromide and promoting bromide excretion. Bromide has a long half-life (10-12 days), and in patients with normal renal function, it is possible to reduce this half-life to approximately 3 days with hydration and diuresis with sodium chloride.³ Alternatively, in patients with impaired renal function or severe intoxication, hemodialysis has been used effectively.⁵

Case Conclusion

The patient was admitted for observation and treated with intravenous sodium chloride. After consultation with his neurologist, he was discharged home in the care of his parents, who were advised to continue him on sodium bromide 185 mg orally twice daily since his seizures were refractory to other anticonvulsant medications.

Dr Repplinger is a medical toxicology fellow in the department of emergency medicine at New York University Langone Medical Center. Dr Nelson, editor of “Case Studies in Toxicology,” is a professor in the department of emergency medicine and director of the medical toxicology fellowship program at the New York University School of Medicine and the New York City Poison Control Center. He is also associate editor, toxicology, of the EMERGENCY MEDICINE editorial board.

Case

An 8-month-old boy with a history of hypotonia, developmental delay, and seizure disorder refractory to multiple anticonvulsant medications, was presented to the ED with a 2-week history of intermittent fever and poor oral intake. His current medications included sodium bromide 185 mg orally twice daily for his seizure disorder.

On physical examination, the boy appeared small for his age, with diffuse hypotonia and diminished reflexes. He was able to track with his eyes but was otherwise unresponsive. No rash was present. Results of initial laboratory studies were: sodium 144 mEq/L; potassium, 4.8 mEq/L; chloride, 179 mEq/L; bicarbonate, 21 mEq/L; blood urea nitrogen, 6 mg/dL; creatinine, 0.1 mg/dL; and glucose, 63 mg/dL. His anion gap (AG) was −56.

What does the anion gap represent?

The AG is a valuable clinical calculation derived from the measured extracellular electrolytes and provides an index of acid-base status.¹ Due to the necessity of electroneutrality, the sum of positive charges (cations) in the extracellular fluid must be balanced exactly with the sum of negative charges (anions). However, to routinely measure all of the cations and anions in the serum would be time-consuming and is also unnecessary. Because most clinical laboratories commonly only measure one relevant cation (sodium) and two anions (chloride and bicarbonate), the positive and negative sums are not completely balanced. The AG therefore refers to this difference (ie, AG = Na – [Cl + HCO₃]).

Of course, electroneutrality exists in vivo, and is accomplished by the presence of unmeasured anions (UA) (eg, lactate and phosphate) and unmeasured cations (UC) (eg, potassium and calcium) not accounted for in the AG (ie, AG = UA – UC). In other words, the sum of measured plus the unmeasured anions must equal the sum of the measured plus unmeasured cations.

What causes a low or negative anion gap?

While most healthcare providers are well versed in the clinical significance of an elevated AG (eg, MUDPILES [methanol, uremia, diabetic ketoacidosis, propylene glycol or phenformin, iron or isoniazid, lactate, ethylene glycol, salicylates]), the meaning of a low or negative AG is underappreciated. There are several scenarios that could potentially yield a low or negative AG, including decreased concentration of UA, increased concentrations of nonsodium cations (UC), and overestimation of serum chloride.

Decreased Concentration of Unmeasured Anions. This most commonly occurs by two mechanisms: dilution of the extracellular fluid or hypoalbuminemia. The addition of water to the extracellular fluid will cause a proportionate dilution of all the measured electrolytes. Since the concentration of measured cations is higher than the measured anions, there is a small and relatively insignificant decrease in the AG.

Alternatively, hypoalbuminemia results in a low AG due to the change in UA; albumin is negatively charged. At physiologic pH, the overwhelming majority of serum proteins are anionic and counter-balanced by the positive charge of sodium. Albumin, the most abundant serum protein, accounts for approximately 75% of the normal AG. Hypoalbuminemic states, such as cirrhosis or nephrotic syndrome, can therefore cause low AG due to the retention of chloride to replace the lost negative charge. The albumin concentration can be corrected to calculate the AG.²

Nonsodium Cations. There are a number of clinical conditions that result in the retention of nonsodium cations. For example, the excess positively charged paraproteins associated with IgG myeloma raise the UC concentration, resulting in a low AG. Similarly, elevations of unmeasured cationic electrolytes, such as calcium and magnesium, may also result in a lower AG. Significant changes in AG, though, are caused only by profound (and often life-threatening) hypercalcemia or hypermagnesemia.

Overestimation of Serum Chloride. Overestimation of serum chloride most commonly occurs in the clinical scenario of bromide exposure. In normal physiologic conditions, chloride is the only halide present in the extracellular fluid. With intake of brominated products, chloride may be partially replaced by bromide. As there is greater renal tubular avidity for bromide, chronic ingestion of bromide results in a gradual rise in serum bromide concentrations with a proportional fall in chloride. However, and more importantly, bromide interferes with a number of laboratory techniques measuring chloride concentrations, resulting in a spuriously elevated chloride, or pseudohyperchloremia. Because the measured sodium and bicarbonate concentrations will remain unchanged, this falsely elevated chloride measurement will result in a negative AG.

What causes the falsely elevated chloride?

All of the current laboratory techniques for measurement of serum chloride concentration can potentially result in a falsely elevated value. However, the degree of pseudohyperchloremia will depend on the specific assay used for measurement. The ion-selective electrode method used by many common laboratory analyzers appears to have the greatest interference on chloride measurement in the presence of bromide. This is simply due to the molecular similarity of bromide and chloride. Conversely, the coulometry method, often used as a reference standard, has the least interference of current laboratory methods.³ This is because coulometry does not completely rely on molecular structure to measure concentration, but rather it measures the amount of energy produced or consumed in an electrolysis reaction. Iodide, another halide compound, has also been described as a cause of pseudohyperchloremia, whereas fluoride does not seem to have significant interference.⁴ 

How are patients exposed to bromide salts?

Bromide salts, specifically sodium bromide, are infrequently used to treat seizure disorders, but are generally reserved for patients with epilepsy refractory to other, less toxic anticonvulsant medications. During the era when bromide salts were more commonly used to treat epilepsy, bromide intoxication, or bromism, was frequently observed.

Bromism may manifest as a constellation of nonspecific neurological and psychiatric symptoms. These most commonly include headache, weakness, agitation, confusion, and hallucinations. In more severe cases of bromism, stupor and coma may occur.^3,5

Although bromide salts are no longer commonly prescribed, a number of products still contain brominated ingredients. Symptoms of bromide intoxication can occur with chronic use of a cough syrup containing dextromethorphan hydrobromide as well as the brominated vegetable oils found in some soft drinks.⁵ 

How is bromism treated?

The treatment of bromism involves preventing further exposure to bromide and promoting bromide excretion. Bromide has a long half-life (10-12 days), and in patients with normal renal function, it is possible to reduce this half-life to approximately 3 days with hydration and diuresis with sodium chloride.³ Alternatively, in patients with impaired renal function or severe intoxication, hemodialysis has been used effectively.⁵

Case Conclusion

The patient was admitted for observation and treated with intravenous sodium chloride. After consultation with his neurologist, he was discharged home in the care of his parents, who were advised to continue him on sodium bromide 185 mg orally twice daily since his seizures were refractory to other anticonvulsant medications.

Dr Repplinger is a medical toxicology fellow in the department of emergency medicine at New York University Langone Medical Center. Dr Nelson, editor of “Case Studies in Toxicology,” is a professor in the department of emergency medicine and director of the medical toxicology fellowship program at the New York University School of Medicine and the New York City Poison Control Center. He is also associate editor, toxicology, of the EMERGENCY MEDICINE editorial board.

Case

An 8-month-old boy with a history of hypotonia, developmental delay, and seizure disorder refractory to multiple anticonvulsant medications, was presented to the ED with a 2-week history of intermittent fever and poor oral intake. His current medications included sodium bromide 185 mg orally twice daily for his seizure disorder.

On physical examination, the boy appeared small for his age, with diffuse hypotonia and diminished reflexes. He was able to track with his eyes but was otherwise unresponsive. No rash was present. Results of initial laboratory studies were: sodium 144 mEq/L; potassium, 4.8 mEq/L; chloride, 179 mEq/L; bicarbonate, 21 mEq/L; blood urea nitrogen, 6 mg/dL; creatinine, 0.1 mg/dL; and glucose, 63 mg/dL. His anion gap (AG) was −56.

What does the anion gap represent?

The AG is a valuable clinical calculation derived from the measured extracellular electrolytes and provides an index of acid-base status.¹ Due to the necessity of electroneutrality, the sum of positive charges (cations) in the extracellular fluid must be balanced exactly with the sum of negative charges (anions). However, to routinely measure all of the cations and anions in the serum would be time-consuming and is also unnecessary. Because most clinical laboratories commonly only measure one relevant cation (sodium) and two anions (chloride and bicarbonate), the positive and negative sums are not completely balanced. The AG therefore refers to this difference (ie, AG = Na – [Cl + HCO₃]).

Of course, electroneutrality exists in vivo, and is accomplished by the presence of unmeasured anions (UA) (eg, lactate and phosphate) and unmeasured cations (UC) (eg, potassium and calcium) not accounted for in the AG (ie, AG = UA – UC). In other words, the sum of measured plus the unmeasured anions must equal the sum of the measured plus unmeasured cations.

What causes a low or negative anion gap?

While most healthcare providers are well versed in the clinical significance of an elevated AG (eg, MUDPILES [methanol, uremia, diabetic ketoacidosis, propylene glycol or phenformin, iron or isoniazid, lactate, ethylene glycol, salicylates]), the meaning of a low or negative AG is underappreciated. There are several scenarios that could potentially yield a low or negative AG, including decreased concentration of UA, increased concentrations of nonsodium cations (UC), and overestimation of serum chloride.

Decreased Concentration of Unmeasured Anions. This most commonly occurs by two mechanisms: dilution of the extracellular fluid or hypoalbuminemia. The addition of water to the extracellular fluid will cause a proportionate dilution of all the measured electrolytes. Since the concentration of measured cations is higher than the measured anions, there is a small and relatively insignificant decrease in the AG.

Alternatively, hypoalbuminemia results in a low AG due to the change in UA; albumin is negatively charged. At physiologic pH, the overwhelming majority of serum proteins are anionic and counter-balanced by the positive charge of sodium. Albumin, the most abundant serum protein, accounts for approximately 75% of the normal AG. Hypoalbuminemic states, such as cirrhosis or nephrotic syndrome, can therefore cause low AG due to the retention of chloride to replace the lost negative charge. The albumin concentration can be corrected to calculate the AG.²

Nonsodium Cations. There are a number of clinical conditions that result in the retention of nonsodium cations. For example, the excess positively charged paraproteins associated with IgG myeloma raise the UC concentration, resulting in a low AG. Similarly, elevations of unmeasured cationic electrolytes, such as calcium and magnesium, may also result in a lower AG. Significant changes in AG, though, are caused only by profound (and often life-threatening) hypercalcemia or hypermagnesemia.

Overestimation of Serum Chloride. Overestimation of serum chloride most commonly occurs in the clinical scenario of bromide exposure. In normal physiologic conditions, chloride is the only halide present in the extracellular fluid. With intake of brominated products, chloride may be partially replaced by bromide. As there is greater renal tubular avidity for bromide, chronic ingestion of bromide results in a gradual rise in serum bromide concentrations with a proportional fall in chloride. However, and more importantly, bromide interferes with a number of laboratory techniques measuring chloride concentrations, resulting in a spuriously elevated chloride, or pseudohyperchloremia. Because the measured sodium and bicarbonate concentrations will remain unchanged, this falsely elevated chloride measurement will result in a negative AG.

What causes the falsely elevated chloride?

All of the current laboratory techniques for measurement of serum chloride concentration can potentially result in a falsely elevated value. However, the degree of pseudohyperchloremia will depend on the specific assay used for measurement. The ion-selective electrode method used by many common laboratory analyzers appears to have the greatest interference on chloride measurement in the presence of bromide. This is simply due to the molecular similarity of bromide and chloride. Conversely, the coulometry method, often used as a reference standard, has the least interference of current laboratory methods.³ This is because coulometry does not completely rely on molecular structure to measure concentration, but rather it measures the amount of energy produced or consumed in an electrolysis reaction. Iodide, another halide compound, has also been described as a cause of pseudohyperchloremia, whereas fluoride does not seem to have significant interference.⁴ 

How are patients exposed to bromide salts?

Bromide salts, specifically sodium bromide, are infrequently used to treat seizure disorders, but are generally reserved for patients with epilepsy refractory to other, less toxic anticonvulsant medications. During the era when bromide salts were more commonly used to treat epilepsy, bromide intoxication, or bromism, was frequently observed.

Bromism may manifest as a constellation of nonspecific neurological and psychiatric symptoms. These most commonly include headache, weakness, agitation, confusion, and hallucinations. In more severe cases of bromism, stupor and coma may occur.^3,5

Although bromide salts are no longer commonly prescribed, a number of products still contain brominated ingredients. Symptoms of bromide intoxication can occur with chronic use of a cough syrup containing dextromethorphan hydrobromide as well as the brominated vegetable oils found in some soft drinks.⁵ 

How is bromism treated?

The treatment of bromism involves preventing further exposure to bromide and promoting bromide excretion. Bromide has a long half-life (10-12 days), and in patients with normal renal function, it is possible to reduce this half-life to approximately 3 days with hydration and diuresis with sodium chloride.³ Alternatively, in patients with impaired renal function or severe intoxication, hemodialysis has been used effectively.⁵

Case Conclusion

The patient was admitted for observation and treated with intravenous sodium chloride. After consultation with his neurologist, he was discharged home in the care of his parents, who were advised to continue him on sodium bromide 185 mg orally twice daily since his seizures were refractory to other anticonvulsant medications.

Dr Repplinger is a medical toxicology fellow in the department of emergency medicine at New York University Langone Medical Center. Dr Nelson, editor of “Case Studies in Toxicology,” is a professor in the department of emergency medicine and director of the medical toxicology fellowship program at the New York University School of Medicine and the New York City Poison Control Center. He is also associate editor, toxicology, of the EMERGENCY MEDICINE editorial board.