News

AGA has issued an updated pragmatic review on sclerosing mesenteritis (SM). Published in Clinical Gastroenterology and Hepatology, the update evaluates available evidence for diagnosis and treatment and examines opportunities for future research in SM, previously known by such names as misty mesentery, mesenteric panniculitis, and inflammatory pseudotumor.

Led by Mark T. Worthington, MD, AGAF, a professor of medicine in the Division of Gastroenterology and Hepatology at the University of Virginia in Charlottesville, Virginia, an expert AGA panel described SM as an uncommon benign idiopathic autoimmune disease of the mesenteric fat. Although of poorly understood etiology, gastroenterologists need to be prepared to diagnose it.

“CT radiologists increasingly are reporting SM and related lesions, such as misty mesentery,” Worthington told GI & Hepatology News. “We are also seeing new SM cases caused by immune checkpoint inhibitors in cancer treatment, and the oncologists ask us to manage this because it interferes with the treatment of the underlying malignancy. Those are often readily treated because we catch them so early.” Metabolic syndrome and associated conditions increase the risk for SM, as does aging.

The recent changes are intended to help clinicians predict disease activity and the need for other testing or treatment. “For instance, most cases are indolent and do not require aggressive treatment — often no treatment at all — but for those that are aggressive, we want the clinician to be able to identify those and make sure the treatment is appropriate. The aggressive cases may warrant tertiary referral,” Worthington said. “A secondary cancer is a possibility in this condition, so drawing from the SM radiology studies, we try to help the clinician decide who needs other testing, such as PET-CT or biopsy, and who can be monitored.”

As many as 60% of cases are asymptomatic, requiring no treatment. Abdominal pain is the most frequent symptom and its location on clinical examination should correspond to the SM lesion on imaging. Treatment involves anti-inflammatory medications tailored to disease severity and clinical response.

No biopsy is not necessary if the lesion meets three of the five CT criteria reported by B. Coulier and has no features of more aggressive disease or malignancy. Although some have suggested that SM may be a paraneoplastic syndrome, current evidence does not support this. SM needs to be differentiated from other diagnoses such as non-Hodgkin’s lymphoma, peritoneal carcinomatosis, and mesenteric fibromatosis.

“There are now CT guidelines for who actually has SM, who needs a biopsy or a PET-CT to rule-out malignancy, and who doesn’t,” said Worthington. “Radiologists do not always use the Coulier criteria for diagnosis, but often they will with encouragement. From this review, a GI clinician should be able to identify SM on CT.”

Epidemiologically, retrospective CT studies have reported a frequency of 0.6%-1.1%, the panelists noted. And while demographic data are limited, a large early case series reported that SM patients had a mean age of 55 years and more likely to be men and of White race.

Patients with SM do not have a higher prevalence of autoimmunity in general, but may have increased rates of metabolic syndrome, obesity, coronary artery disease, and urolithiasis, the panelists noted.

The update allows room for differences in clinical judgment. “For instance, a longer or more frequent CT surveillance interval can be justified depending on the patient’s findings, and no one should feel locked in by these recommendations,” Worthington said.

 

Medical Therapy

Although there is no surgical cure, pharmacologic options are many. These include prednisone, tamoxifen, colchicine, azathioprine, thalidomide, cyclophosphamide, and methotrexate, as well as the biologics rituximab, infliximab and ustekinumab. Current corticosteroid-based therapies often require months to achieve a clinical response, however.

Bowel obstruction is managed nonoperatively when feasible, but medically refractory disease may require surgical bypass.

Offering his perspective on the guidance but not involved in its formulation, Gastroenterologist Stephen B. Hanauer, MD, AGAF, a professor of medicine at Northwestern Medicine in Chicago, said, “The most useful component of the practical review is the algorithm for diagnosis and determination when biopsy or follow-up imaging is reasonable in the absence of evidence.” He stressed that the recommendations are pragmatic rather than evidence-based “as there are no controlled trials and the presentation is heterogeneous.”

Hanauer added that none of the recommended treatments have been shown to impact reduction on imaging. “Hence, all of the treatments are empiric without biological or imaging endpoints.”

In his experience, patients with inflammatory features are the best candidates for immune-directed therapies as reduction in inflammatory markers is a potential endpoint, although no therapies have demonstrated an effect on imaging or progression. “As an IBD doctor, I favor steroids and azathioprine or anti-TNF directed therapy, but again, there is no evidence beyond reports of symptomatic improvement.” 

Worthington and colleagues agreed that treatment protocols have developed empirically. “Future investigation for symptomatic SM should focus on the nature of the inflammatory response, including causative cytokines and other proinflammatory mediators, the goal being targeted therapy with fewer side effects and a more rapid clinical response,” they wrote.

Currently, said Worthington, the biggest gaps remain in treatment. “Even the best studies are small and anecdotal, and we do not know the cytokine or other proinflammatory mediators.”

This guidance was supported by the AGA. Worthington reported renumeration from TriCity Surgery Center, Prescott, Ariz. Hanauer had no conflicts of interest relevant to their comments.

A version of this article appeared on Medscape.com.

AGA has issued an updated pragmatic review on sclerosing mesenteritis (SM). Published in Clinical Gastroenterology and Hepatology, the update evaluates available evidence for diagnosis and treatment and examines opportunities for future research in SM, previously known by such names as misty mesentery, mesenteric panniculitis, and inflammatory pseudotumor.

Led by Mark T. Worthington, MD, AGAF, a professor of medicine in the Division of Gastroenterology and Hepatology at the University of Virginia in Charlottesville, Virginia, an expert AGA panel described SM as an uncommon benign idiopathic autoimmune disease of the mesenteric fat. Although of poorly understood etiology, gastroenterologists need to be prepared to diagnose it.

“CT radiologists increasingly are reporting SM and related lesions, such as misty mesentery,” Worthington told GI & Hepatology News. “We are also seeing new SM cases caused by immune checkpoint inhibitors in cancer treatment, and the oncologists ask us to manage this because it interferes with the treatment of the underlying malignancy. Those are often readily treated because we catch them so early.” Metabolic syndrome and associated conditions increase the risk for SM, as does aging.

The recent changes are intended to help clinicians predict disease activity and the need for other testing or treatment. “For instance, most cases are indolent and do not require aggressive treatment — often no treatment at all — but for those that are aggressive, we want the clinician to be able to identify those and make sure the treatment is appropriate. The aggressive cases may warrant tertiary referral,” Worthington said. “A secondary cancer is a possibility in this condition, so drawing from the SM radiology studies, we try to help the clinician decide who needs other testing, such as PET-CT or biopsy, and who can be monitored.”

As many as 60% of cases are asymptomatic, requiring no treatment. Abdominal pain is the most frequent symptom and its location on clinical examination should correspond to the SM lesion on imaging. Treatment involves anti-inflammatory medications tailored to disease severity and clinical response.

No biopsy is not necessary if the lesion meets three of the five CT criteria reported by B. Coulier and has no features of more aggressive disease or malignancy. Although some have suggested that SM may be a paraneoplastic syndrome, current evidence does not support this. SM needs to be differentiated from other diagnoses such as non-Hodgkin’s lymphoma, peritoneal carcinomatosis, and mesenteric fibromatosis.

“There are now CT guidelines for who actually has SM, who needs a biopsy or a PET-CT to rule-out malignancy, and who doesn’t,” said Worthington. “Radiologists do not always use the Coulier criteria for diagnosis, but often they will with encouragement. From this review, a GI clinician should be able to identify SM on CT.”

Epidemiologically, retrospective CT studies have reported a frequency of 0.6%-1.1%, the panelists noted. And while demographic data are limited, a large early case series reported that SM patients had a mean age of 55 years and more likely to be men and of White race.

Patients with SM do not have a higher prevalence of autoimmunity in general, but may have increased rates of metabolic syndrome, obesity, coronary artery disease, and urolithiasis, the panelists noted.

The update allows room for differences in clinical judgment. “For instance, a longer or more frequent CT surveillance interval can be justified depending on the patient’s findings, and no one should feel locked in by these recommendations,” Worthington said.

 

Medical Therapy

Although there is no surgical cure, pharmacologic options are many. These include prednisone, tamoxifen, colchicine, azathioprine, thalidomide, cyclophosphamide, and methotrexate, as well as the biologics rituximab, infliximab and ustekinumab. Current corticosteroid-based therapies often require months to achieve a clinical response, however.

Bowel obstruction is managed nonoperatively when feasible, but medically refractory disease may require surgical bypass.

Offering his perspective on the guidance but not involved in its formulation, Gastroenterologist Stephen B. Hanauer, MD, AGAF, a professor of medicine at Northwestern Medicine in Chicago, said, “The most useful component of the practical review is the algorithm for diagnosis and determination when biopsy or follow-up imaging is reasonable in the absence of evidence.” He stressed that the recommendations are pragmatic rather than evidence-based “as there are no controlled trials and the presentation is heterogeneous.”

Hanauer added that none of the recommended treatments have been shown to impact reduction on imaging. “Hence, all of the treatments are empiric without biological or imaging endpoints.”

In his experience, patients with inflammatory features are the best candidates for immune-directed therapies as reduction in inflammatory markers is a potential endpoint, although no therapies have demonstrated an effect on imaging or progression. “As an IBD doctor, I favor steroids and azathioprine or anti-TNF directed therapy, but again, there is no evidence beyond reports of symptomatic improvement.” 

Worthington and colleagues agreed that treatment protocols have developed empirically. “Future investigation for symptomatic SM should focus on the nature of the inflammatory response, including causative cytokines and other proinflammatory mediators, the goal being targeted therapy with fewer side effects and a more rapid clinical response,” they wrote.

Currently, said Worthington, the biggest gaps remain in treatment. “Even the best studies are small and anecdotal, and we do not know the cytokine or other proinflammatory mediators.”

This guidance was supported by the AGA. Worthington reported renumeration from TriCity Surgery Center, Prescott, Ariz. Hanauer had no conflicts of interest relevant to their comments.

A version of this article appeared on Medscape.com.

AGA has issued an updated pragmatic review on sclerosing mesenteritis (SM). Published in Clinical Gastroenterology and Hepatology, the update evaluates available evidence for diagnosis and treatment and examines opportunities for future research in SM, previously known by such names as misty mesentery, mesenteric panniculitis, and inflammatory pseudotumor.

Led by Mark T. Worthington, MD, AGAF, a professor of medicine in the Division of Gastroenterology and Hepatology at the University of Virginia in Charlottesville, Virginia, an expert AGA panel described SM as an uncommon benign idiopathic autoimmune disease of the mesenteric fat. Although of poorly understood etiology, gastroenterologists need to be prepared to diagnose it.

“CT radiologists increasingly are reporting SM and related lesions, such as misty mesentery,” Worthington told GI & Hepatology News. “We are also seeing new SM cases caused by immune checkpoint inhibitors in cancer treatment, and the oncologists ask us to manage this because it interferes with the treatment of the underlying malignancy. Those are often readily treated because we catch them so early.” Metabolic syndrome and associated conditions increase the risk for SM, as does aging.

The recent changes are intended to help clinicians predict disease activity and the need for other testing or treatment. “For instance, most cases are indolent and do not require aggressive treatment — often no treatment at all — but for those that are aggressive, we want the clinician to be able to identify those and make sure the treatment is appropriate. The aggressive cases may warrant tertiary referral,” Worthington said. “A secondary cancer is a possibility in this condition, so drawing from the SM radiology studies, we try to help the clinician decide who needs other testing, such as PET-CT or biopsy, and who can be monitored.”

As many as 60% of cases are asymptomatic, requiring no treatment. Abdominal pain is the most frequent symptom and its location on clinical examination should correspond to the SM lesion on imaging. Treatment involves anti-inflammatory medications tailored to disease severity and clinical response.

No biopsy is not necessary if the lesion meets three of the five CT criteria reported by B. Coulier and has no features of more aggressive disease or malignancy. Although some have suggested that SM may be a paraneoplastic syndrome, current evidence does not support this. SM needs to be differentiated from other diagnoses such as non-Hodgkin’s lymphoma, peritoneal carcinomatosis, and mesenteric fibromatosis.

“There are now CT guidelines for who actually has SM, who needs a biopsy or a PET-CT to rule-out malignancy, and who doesn’t,” said Worthington. “Radiologists do not always use the Coulier criteria for diagnosis, but often they will with encouragement. From this review, a GI clinician should be able to identify SM on CT.”

Epidemiologically, retrospective CT studies have reported a frequency of 0.6%-1.1%, the panelists noted. And while demographic data are limited, a large early case series reported that SM patients had a mean age of 55 years and more likely to be men and of White race.

Patients with SM do not have a higher prevalence of autoimmunity in general, but may have increased rates of metabolic syndrome, obesity, coronary artery disease, and urolithiasis, the panelists noted.

The update allows room for differences in clinical judgment. “For instance, a longer or more frequent CT surveillance interval can be justified depending on the patient’s findings, and no one should feel locked in by these recommendations,” Worthington said.

 

Medical Therapy

Although there is no surgical cure, pharmacologic options are many. These include prednisone, tamoxifen, colchicine, azathioprine, thalidomide, cyclophosphamide, and methotrexate, as well as the biologics rituximab, infliximab and ustekinumab. Current corticosteroid-based therapies often require months to achieve a clinical response, however.

Bowel obstruction is managed nonoperatively when feasible, but medically refractory disease may require surgical bypass.

Offering his perspective on the guidance but not involved in its formulation, Gastroenterologist Stephen B. Hanauer, MD, AGAF, a professor of medicine at Northwestern Medicine in Chicago, said, “The most useful component of the practical review is the algorithm for diagnosis and determination when biopsy or follow-up imaging is reasonable in the absence of evidence.” He stressed that the recommendations are pragmatic rather than evidence-based “as there are no controlled trials and the presentation is heterogeneous.”

Hanauer added that none of the recommended treatments have been shown to impact reduction on imaging. “Hence, all of the treatments are empiric without biological or imaging endpoints.”

In his experience, patients with inflammatory features are the best candidates for immune-directed therapies as reduction in inflammatory markers is a potential endpoint, although no therapies have demonstrated an effect on imaging or progression. “As an IBD doctor, I favor steroids and azathioprine or anti-TNF directed therapy, but again, there is no evidence beyond reports of symptomatic improvement.” 

Worthington and colleagues agreed that treatment protocols have developed empirically. “Future investigation for symptomatic SM should focus on the nature of the inflammatory response, including causative cytokines and other proinflammatory mediators, the goal being targeted therapy with fewer side effects and a more rapid clinical response,” they wrote.

Currently, said Worthington, the biggest gaps remain in treatment. “Even the best studies are small and anecdotal, and we do not know the cytokine or other proinflammatory mediators.”

This guidance was supported by the AGA. Worthington reported renumeration from TriCity Surgery Center, Prescott, Ariz. Hanauer had no conflicts of interest relevant to their comments.

A version of this article appeared on Medscape.com.

The Veterans Health Administration (VHA) paid about $828 million in recruitment and retention incentives from 2020 to 2023, but the process for providing an estimated $340.9 million of that was not “effectively governed” according to a recent US Department of Veterans Affairs (VA) Office of Inspector General (OIG) investigation.

About one-third of incentives were missing forms or signatures, or lacked sufficient justification, for the payments to about 130,000 VHA employees. In the report, the OIG notes the VHA has faced “long-standing challenges related to occupational shortages,” adding that a shortage occupation designation does not mean there are actual shortages at a facility.

“Most shortage occupations continue to experience annual net growth and are not critically understaffed in most facilities,” the report says.

More than 85% of incentive monies in 2022 and 2023 were paid to employees in occupations on staffing shortage lists. OIG estimated the VHA paid incentives to 38,800 employees (about 30%) where the award justification could not be verified or was insufficient.

Amplified by the COVID-19 pandemic and the PACT Act, the need to recruit and retain employees peaked in 2021, when record numbers of health care workers left their jobs. An October 2021 survey of 1000 medical professionals found nearly 1 in 5 health care workers quit during the pandemic, with most citing stress and burnout, and an additional 31% were considering quitting. When the PACT Act was signed into law in August 2022, it created thousands of newly benefits-eligible veterans.

In May 2022, the VA reported it needed to hire 52,000 employees annually for the next 5 years to keep up. In response, the VA released a 10-step plan to support recruitment and retention, focusing on raising wages when possible and finding other incentives when it wasn’t (ie, relocation bonuses or greater flexibility for remote work). The OIG report acknowledged the pandemic exacerbated VHA’s recruitment and retention challenges. 

By 2024, the VA had not only reduced employee turnover by 20% over the prior 2 years, but had also exceeded its hiring goals. The VHA workforce grew by 7.4% in fiscal year 2023, its highest rate of growth in > 15 years.

VA officials must retain the documentation for incentives for 6 years so the process can be reconstructed if necessary. However, the OIG report noted “numerous instances” where documentation couldn’t be produced and therefore could not determine whether the incentives complied with policy. 

The report also identified 28 employees who received retention incentive payments long after their award period had expired. The VA paid about $4.6 million for incentives that should have been terminated. The VA reported that it is pursuing debt collection for 27 of the 28 employees. 

Only if the “identified weaknesses” are addressed will the VHA have assurance that incentives are being used effectively, the OIG said. Its recommendations included enforcing quality control checks and establishing accountability measures. The OIG also recommended establishing oversight procedures to review retention incentives annually, recertify them if appropriate, or terminate them.

The Veterans Health Administration (VHA) paid about $828 million in recruitment and retention incentives from 2020 to 2023, but the process for providing an estimated $340.9 million of that was not “effectively governed” according to a recent US Department of Veterans Affairs (VA) Office of Inspector General (OIG) investigation.

About one-third of incentives were missing forms or signatures, or lacked sufficient justification, for the payments to about 130,000 VHA employees. In the report, the OIG notes the VHA has faced “long-standing challenges related to occupational shortages,” adding that a shortage occupation designation does not mean there are actual shortages at a facility.

“Most shortage occupations continue to experience annual net growth and are not critically understaffed in most facilities,” the report says.

More than 85% of incentive monies in 2022 and 2023 were paid to employees in occupations on staffing shortage lists. OIG estimated the VHA paid incentives to 38,800 employees (about 30%) where the award justification could not be verified or was insufficient.

Amplified by the COVID-19 pandemic and the PACT Act, the need to recruit and retain employees peaked in 2021, when record numbers of health care workers left their jobs. An October 2021 survey of 1000 medical professionals found nearly 1 in 5 health care workers quit during the pandemic, with most citing stress and burnout, and an additional 31% were considering quitting. When the PACT Act was signed into law in August 2022, it created thousands of newly benefits-eligible veterans.

In May 2022, the VA reported it needed to hire 52,000 employees annually for the next 5 years to keep up. In response, the VA released a 10-step plan to support recruitment and retention, focusing on raising wages when possible and finding other incentives when it wasn’t (ie, relocation bonuses or greater flexibility for remote work). The OIG report acknowledged the pandemic exacerbated VHA’s recruitment and retention challenges. 

By 2024, the VA had not only reduced employee turnover by 20% over the prior 2 years, but had also exceeded its hiring goals. The VHA workforce grew by 7.4% in fiscal year 2023, its highest rate of growth in > 15 years.

VA officials must retain the documentation for incentives for 6 years so the process can be reconstructed if necessary. However, the OIG report noted “numerous instances” where documentation couldn’t be produced and therefore could not determine whether the incentives complied with policy. 

The report also identified 28 employees who received retention incentive payments long after their award period had expired. The VA paid about $4.6 million for incentives that should have been terminated. The VA reported that it is pursuing debt collection for 27 of the 28 employees. 

Only if the “identified weaknesses” are addressed will the VHA have assurance that incentives are being used effectively, the OIG said. Its recommendations included enforcing quality control checks and establishing accountability measures. The OIG also recommended establishing oversight procedures to review retention incentives annually, recertify them if appropriate, or terminate them.

The Veterans Health Administration (VHA) paid about $828 million in recruitment and retention incentives from 2020 to 2023, but the process for providing an estimated $340.9 million of that was not “effectively governed” according to a recent US Department of Veterans Affairs (VA) Office of Inspector General (OIG) investigation.

About one-third of incentives were missing forms or signatures, or lacked sufficient justification, for the payments to about 130,000 VHA employees. In the report, the OIG notes the VHA has faced “long-standing challenges related to occupational shortages,” adding that a shortage occupation designation does not mean there are actual shortages at a facility.

“Most shortage occupations continue to experience annual net growth and are not critically understaffed in most facilities,” the report says.

More than 85% of incentive monies in 2022 and 2023 were paid to employees in occupations on staffing shortage lists. OIG estimated the VHA paid incentives to 38,800 employees (about 30%) where the award justification could not be verified or was insufficient.

Amplified by the COVID-19 pandemic and the PACT Act, the need to recruit and retain employees peaked in 2021, when record numbers of health care workers left their jobs. An October 2021 survey of 1000 medical professionals found nearly 1 in 5 health care workers quit during the pandemic, with most citing stress and burnout, and an additional 31% were considering quitting. When the PACT Act was signed into law in August 2022, it created thousands of newly benefits-eligible veterans.

In May 2022, the VA reported it needed to hire 52,000 employees annually for the next 5 years to keep up. In response, the VA released a 10-step plan to support recruitment and retention, focusing on raising wages when possible and finding other incentives when it wasn’t (ie, relocation bonuses or greater flexibility for remote work). The OIG report acknowledged the pandemic exacerbated VHA’s recruitment and retention challenges. 

By 2024, the VA had not only reduced employee turnover by 20% over the prior 2 years, but had also exceeded its hiring goals. The VHA workforce grew by 7.4% in fiscal year 2023, its highest rate of growth in > 15 years.

VA officials must retain the documentation for incentives for 6 years so the process can be reconstructed if necessary. However, the OIG report noted “numerous instances” where documentation couldn’t be produced and therefore could not determine whether the incentives complied with policy. 

The report also identified 28 employees who received retention incentive payments long after their award period had expired. The VA paid about $4.6 million for incentives that should have been terminated. The VA reported that it is pursuing debt collection for 27 of the 28 employees. 

Only if the “identified weaknesses” are addressed will the VHA have assurance that incentives are being used effectively, the OIG said. Its recommendations included enforcing quality control checks and establishing accountability measures. The OIG also recommended establishing oversight procedures to review retention incentives annually, recertify them if appropriate, or terminate them.

Think your patient may have celiac disease? The harsh reality is that current diagnostic tests require patients to consume gluten for an accurate diagnosis, which poses challenges for individuals already avoiding gluten.

A more tolerable approach appears to be on the horizon. Researchers in Australia have developed a blood test that can identify celiac disease with high sensitivity and specificity, even without consuming gluten.

“This is a simple and accurate test that can provide a diagnosis within a very short time frame, without the need for patients to continue eating gluten and feeling sick, or to wait months for a gastroscopy,” Olivia Moscatelli, PhD candidate, Tye-Din Lab, Walter and Eliza Hall Institute and University of Melbourne, Parkville, Australia, told GI & Hepatology News.

The study was published in Gastroenterology.

 

Most Cases Go Undiagnosed

Celiac disease is an autoimmune disorder triggered by gluten found in wheat, rye, and barley. The only available treatment is a strict, life-long gluten-free diet.

The global prevalence of celiac disease is estimated at around 1%-2%, with 50%-80% of cases either undiagnosed or diagnosed late. That’s because the current reliable diagnosis of celiac disease requires the intake of gluten, which may deter people from seeking a diagnosis.

In earlier work, the researchers, working with Robert Anderson, MBChB, BMedSc, PhD, AGAF, now with Novoviah Pharmaceuticals, made the unexpected discovery that interleukin-2 (IL-2) spiked in the blood of people with celiac disease shortly after they ate gluten.

But would this signal be present when no gluten had been consumed?

The team developed and tested a simple whole blood assay measuring IL-2 release (WBAIL- 2) for detecting gluten-specific T cells to aid in diagnosing celiac disease.

They collected blood samples from 181 volunteers — 75 with treated celiac disease on a gluten-free diet, 13 with active untreated celiac disease, 32 with nonceliac gluten sensitivity and 61 healthy controls. The blood samples were mixed with gluten in a test tube for a day to see if the IL-2 signal appeared.

The WBAIL-2 assay demonstrated high accuracy for celiac disease, even in patients following a strict gluten-free diet.

For patients with HLA-DQ2.5+ genetics, sensitivity was 90% and specificity was 95%, with lower sensitivity (56%) for patients with HLA-DQ8+ celiac disease.

The WBAIL-2 assay correlated strongly with the frequency of tetramer-positive gluten-specific CD4+ T cells used to diagnose celiac disease and monitor treatment effectiveness, and with serum IL-2 levels after gluten challenge.

The strength of the IL-2 signal correlated with the severity of a patient’s symptoms, “allowing us to predict how severely a person with celiac disease might react to gluten, without them actually having to eat it,” Moscatelli said in a news release.

“Current diagnostic practice involves a blood-based serology test followed by a confirmatory gastroscopy if positive. Both tests require the patient to eat gluten daily for 6-12 weeks prior for accurate results. We envision the new blood test (IL-2 whole blood assay) will replace the invasive gastroscopy as the confirmatory test following positive serology,” Moscatelli told GI & Hepatology News.

“In people already following a gluten-free diet, we propose they would have this new blood test done on two separate occasions and two positive results would be required for a celiac diagnosis. This would allow a large number of people who previously have been unable to go through the current diagnostic process to receive a diagnosis,” Moscatelli said.

 

Practice Changing Potential 

A blood-based test that can accurately detect celiac disease without the need for a gluten challenge would be “welcome and practice changing,” said Christopher Cao, MD, director, Celiac Disease Program, Division of Gastroenterology, Mount Sinai Health System, New York City.

“A typical ‘gluten challenge’ involves eating the equivalent of 1-2 slices of bread daily for the course of 6 weeks, and this may be incredibly difficult for patients who have already been on a gluten-free diet prior to an official celiac disease diagnosis. Inability to perform a gluten challenge limits the ability to make an accurate celiac disease diagnosis,” Cao told GI & Hepatology News.

“This study shows that gluten-stimulated interleukin release 2 assays may correlate with the presence of pathogenic gluten-specific CD4+ T cell response in celiac disease,” Cao noted.

He cautioned that “further large cohort, multicenter prospective studies are needed to assess generalizability and may be helpful in evaluating the accuracy of WBAIL-2 in non-HLA DQ2.5 genotypes.” 

Other considerations prior to implementation may include reproducibility across different laboratories and overall cost effectiveness, Cao said. “Ultimately in clinic, the role of WBAIL-2 will need to be better defined within the algorithm of celiac disease testing,” he added.

 

The Path Ahead

The researchers plan to test the performance of the IL-2 whole blood assay in a pediatric cohort, as well as in other countries to demonstrate the reproducibility of the test. In these studies, the test will likely be performed alongside the current diagnostic tests (serology and gastroscopy), Moscatelli told GI & Hepatology News.

“There are some validation studies starting in other countries already as many celiac clinicians globally are interested in bringing this test to their clinical practice. I believe the plan is to have this as an approved diagnostic test for celiac disease worldwide,” she said.

Novoviah Pharmaceuticals is managing the commercialization of the test, and the plan is to get it into clinical practice in the next 2 years, Moscatelli said.

The research was supported by Coeliac Australia, Novoviah Pharmaceuticals (who provided the proprietary test for this study), Beck Family Foundation, Butterfield Family, the Veith Foundation. A complete list of author disclosures is available with the original article. Cao had no relevant disclosures.

A version of this article appeared on Medscape.com.

Think your patient may have celiac disease? The harsh reality is that current diagnostic tests require patients to consume gluten for an accurate diagnosis, which poses challenges for individuals already avoiding gluten.

A more tolerable approach appears to be on the horizon. Researchers in Australia have developed a blood test that can identify celiac disease with high sensitivity and specificity, even without consuming gluten.

“This is a simple and accurate test that can provide a diagnosis within a very short time frame, without the need for patients to continue eating gluten and feeling sick, or to wait months for a gastroscopy,” Olivia Moscatelli, PhD candidate, Tye-Din Lab, Walter and Eliza Hall Institute and University of Melbourne, Parkville, Australia, told GI & Hepatology News.

The study was published in Gastroenterology.

 

Most Cases Go Undiagnosed

Celiac disease is an autoimmune disorder triggered by gluten found in wheat, rye, and barley. The only available treatment is a strict, life-long gluten-free diet.

The global prevalence of celiac disease is estimated at around 1%-2%, with 50%-80% of cases either undiagnosed or diagnosed late. That’s because the current reliable diagnosis of celiac disease requires the intake of gluten, which may deter people from seeking a diagnosis.

In earlier work, the researchers, working with Robert Anderson, MBChB, BMedSc, PhD, AGAF, now with Novoviah Pharmaceuticals, made the unexpected discovery that interleukin-2 (IL-2) spiked in the blood of people with celiac disease shortly after they ate gluten.

But would this signal be present when no gluten had been consumed?

The team developed and tested a simple whole blood assay measuring IL-2 release (WBAIL- 2) for detecting gluten-specific T cells to aid in diagnosing celiac disease.

They collected blood samples from 181 volunteers — 75 with treated celiac disease on a gluten-free diet, 13 with active untreated celiac disease, 32 with nonceliac gluten sensitivity and 61 healthy controls. The blood samples were mixed with gluten in a test tube for a day to see if the IL-2 signal appeared.

The WBAIL-2 assay demonstrated high accuracy for celiac disease, even in patients following a strict gluten-free diet.

For patients with HLA-DQ2.5+ genetics, sensitivity was 90% and specificity was 95%, with lower sensitivity (56%) for patients with HLA-DQ8+ celiac disease.

The WBAIL-2 assay correlated strongly with the frequency of tetramer-positive gluten-specific CD4+ T cells used to diagnose celiac disease and monitor treatment effectiveness, and with serum IL-2 levels after gluten challenge.

The strength of the IL-2 signal correlated with the severity of a patient’s symptoms, “allowing us to predict how severely a person with celiac disease might react to gluten, without them actually having to eat it,” Moscatelli said in a news release.

“Current diagnostic practice involves a blood-based serology test followed by a confirmatory gastroscopy if positive. Both tests require the patient to eat gluten daily for 6-12 weeks prior for accurate results. We envision the new blood test (IL-2 whole blood assay) will replace the invasive gastroscopy as the confirmatory test following positive serology,” Moscatelli told GI & Hepatology News.

“In people already following a gluten-free diet, we propose they would have this new blood test done on two separate occasions and two positive results would be required for a celiac diagnosis. This would allow a large number of people who previously have been unable to go through the current diagnostic process to receive a diagnosis,” Moscatelli said.

 

Practice Changing Potential 

A blood-based test that can accurately detect celiac disease without the need for a gluten challenge would be “welcome and practice changing,” said Christopher Cao, MD, director, Celiac Disease Program, Division of Gastroenterology, Mount Sinai Health System, New York City.

“A typical ‘gluten challenge’ involves eating the equivalent of 1-2 slices of bread daily for the course of 6 weeks, and this may be incredibly difficult for patients who have already been on a gluten-free diet prior to an official celiac disease diagnosis. Inability to perform a gluten challenge limits the ability to make an accurate celiac disease diagnosis,” Cao told GI & Hepatology News.

“This study shows that gluten-stimulated interleukin release 2 assays may correlate with the presence of pathogenic gluten-specific CD4+ T cell response in celiac disease,” Cao noted.

He cautioned that “further large cohort, multicenter prospective studies are needed to assess generalizability and may be helpful in evaluating the accuracy of WBAIL-2 in non-HLA DQ2.5 genotypes.” 

Other considerations prior to implementation may include reproducibility across different laboratories and overall cost effectiveness, Cao said. “Ultimately in clinic, the role of WBAIL-2 will need to be better defined within the algorithm of celiac disease testing,” he added.

 

The Path Ahead

The researchers plan to test the performance of the IL-2 whole blood assay in a pediatric cohort, as well as in other countries to demonstrate the reproducibility of the test. In these studies, the test will likely be performed alongside the current diagnostic tests (serology and gastroscopy), Moscatelli told GI & Hepatology News.

“There are some validation studies starting in other countries already as many celiac clinicians globally are interested in bringing this test to their clinical practice. I believe the plan is to have this as an approved diagnostic test for celiac disease worldwide,” she said.

Novoviah Pharmaceuticals is managing the commercialization of the test, and the plan is to get it into clinical practice in the next 2 years, Moscatelli said.

The research was supported by Coeliac Australia, Novoviah Pharmaceuticals (who provided the proprietary test for this study), Beck Family Foundation, Butterfield Family, the Veith Foundation. A complete list of author disclosures is available with the original article. Cao had no relevant disclosures.

A version of this article appeared on Medscape.com.

Think your patient may have celiac disease? The harsh reality is that current diagnostic tests require patients to consume gluten for an accurate diagnosis, which poses challenges for individuals already avoiding gluten.

A more tolerable approach appears to be on the horizon. Researchers in Australia have developed a blood test that can identify celiac disease with high sensitivity and specificity, even without consuming gluten.

“This is a simple and accurate test that can provide a diagnosis within a very short time frame, without the need for patients to continue eating gluten and feeling sick, or to wait months for a gastroscopy,” Olivia Moscatelli, PhD candidate, Tye-Din Lab, Walter and Eliza Hall Institute and University of Melbourne, Parkville, Australia, told GI & Hepatology News.

The study was published in Gastroenterology.

 

Most Cases Go Undiagnosed

Celiac disease is an autoimmune disorder triggered by gluten found in wheat, rye, and barley. The only available treatment is a strict, life-long gluten-free diet.

The global prevalence of celiac disease is estimated at around 1%-2%, with 50%-80% of cases either undiagnosed or diagnosed late. That’s because the current reliable diagnosis of celiac disease requires the intake of gluten, which may deter people from seeking a diagnosis.

In earlier work, the researchers, working with Robert Anderson, MBChB, BMedSc, PhD, AGAF, now with Novoviah Pharmaceuticals, made the unexpected discovery that interleukin-2 (IL-2) spiked in the blood of people with celiac disease shortly after they ate gluten.

But would this signal be present when no gluten had been consumed?

The team developed and tested a simple whole blood assay measuring IL-2 release (WBAIL- 2) for detecting gluten-specific T cells to aid in diagnosing celiac disease.

They collected blood samples from 181 volunteers — 75 with treated celiac disease on a gluten-free diet, 13 with active untreated celiac disease, 32 with nonceliac gluten sensitivity and 61 healthy controls. The blood samples were mixed with gluten in a test tube for a day to see if the IL-2 signal appeared.

The WBAIL-2 assay demonstrated high accuracy for celiac disease, even in patients following a strict gluten-free diet.

For patients with HLA-DQ2.5+ genetics, sensitivity was 90% and specificity was 95%, with lower sensitivity (56%) for patients with HLA-DQ8+ celiac disease.

The WBAIL-2 assay correlated strongly with the frequency of tetramer-positive gluten-specific CD4+ T cells used to diagnose celiac disease and monitor treatment effectiveness, and with serum IL-2 levels after gluten challenge.

The strength of the IL-2 signal correlated with the severity of a patient’s symptoms, “allowing us to predict how severely a person with celiac disease might react to gluten, without them actually having to eat it,” Moscatelli said in a news release.

“Current diagnostic practice involves a blood-based serology test followed by a confirmatory gastroscopy if positive. Both tests require the patient to eat gluten daily for 6-12 weeks prior for accurate results. We envision the new blood test (IL-2 whole blood assay) will replace the invasive gastroscopy as the confirmatory test following positive serology,” Moscatelli told GI & Hepatology News.

“In people already following a gluten-free diet, we propose they would have this new blood test done on two separate occasions and two positive results would be required for a celiac diagnosis. This would allow a large number of people who previously have been unable to go through the current diagnostic process to receive a diagnosis,” Moscatelli said.

 

Practice Changing Potential 

A blood-based test that can accurately detect celiac disease without the need for a gluten challenge would be “welcome and practice changing,” said Christopher Cao, MD, director, Celiac Disease Program, Division of Gastroenterology, Mount Sinai Health System, New York City.

“A typical ‘gluten challenge’ involves eating the equivalent of 1-2 slices of bread daily for the course of 6 weeks, and this may be incredibly difficult for patients who have already been on a gluten-free diet prior to an official celiac disease diagnosis. Inability to perform a gluten challenge limits the ability to make an accurate celiac disease diagnosis,” Cao told GI & Hepatology News.

“This study shows that gluten-stimulated interleukin release 2 assays may correlate with the presence of pathogenic gluten-specific CD4+ T cell response in celiac disease,” Cao noted.

He cautioned that “further large cohort, multicenter prospective studies are needed to assess generalizability and may be helpful in evaluating the accuracy of WBAIL-2 in non-HLA DQ2.5 genotypes.” 

Other considerations prior to implementation may include reproducibility across different laboratories and overall cost effectiveness, Cao said. “Ultimately in clinic, the role of WBAIL-2 will need to be better defined within the algorithm of celiac disease testing,” he added.

 

The Path Ahead

The researchers plan to test the performance of the IL-2 whole blood assay in a pediatric cohort, as well as in other countries to demonstrate the reproducibility of the test. In these studies, the test will likely be performed alongside the current diagnostic tests (serology and gastroscopy), Moscatelli told GI & Hepatology News.

“There are some validation studies starting in other countries already as many celiac clinicians globally are interested in bringing this test to their clinical practice. I believe the plan is to have this as an approved diagnostic test for celiac disease worldwide,” she said.

Novoviah Pharmaceuticals is managing the commercialization of the test, and the plan is to get it into clinical practice in the next 2 years, Moscatelli said.

The research was supported by Coeliac Australia, Novoviah Pharmaceuticals (who provided the proprietary test for this study), Beck Family Foundation, Butterfield Family, the Veith Foundation. A complete list of author disclosures is available with the original article. Cao had no relevant disclosures.

A version of this article appeared on Medscape.com.

WASHINGTON — For years, oncologist Jonathan Peled, MD, PhD, and his colleagues at Memorial Sloan Kettering Cancer Center (MSKCC) in New York City have been documenting gut microbiota disruption during allogeneic hematopoietic stem cell transplantation (allo-HSCT) and its role in frequent and potentially fatal bloodstream infections (BSIs) in the first 100 days after transplant.

Modulating microbiome composition to improve outcomes after allo-HSCT for hematological malignancies is a prime goal, and at the Gut Microbiota for Health (GMFH) World Summit 2025, Peled shared two new findings.

In one study, his team found that sucrose can exacerbate antibiotic-induced microbiome injury in patients undergoing allo-HSCT — a finding that “raises the question of whether our dietary recommendations [for] allo-HSCT patients are correct,” said Peled, assistant attending at MSKCC, during a session on the gut microbiome and oncology.

And in another study, they found that a rationally designed probiotic formulation may help lower the incidence of bacterial BSIs. In December 2024, the probiotic formulation (SER-155, Seres Therapeutics, Inc.) was granted breakthrough therapy designation by the FDA.

With immunotherapies more broadly, researchers are increasingly looking at diet and modulation of the microbiome to improve both treatment tolerance and efficacy, experts said at the meeting convened by the AGA and the European Society of Neurogastroenterology and Motility.

“Cancer patients and caregivers are asking, ‘What should I eat?’” said Carrie Daniel-MacDougall, PhD, MPH, a nutritional epidemiologist at the University of Texas MD Anderson Cancer Center in Houston. “They’re not just focused on side effects — they want a good outcome for their treatment, and they’re exploring a lot of dietary strategies [for which there] is not a lot of evidence.”

Clinicians are challenged by the fact that “we don’t typically collect dietary data in clinical trials of cancer drugs,” leaving them to extrapolate from evidence-based diet guidelines for cancer prevention, Daniel-MacDougall said.

But “I think that’s starting to shift,” she said, with the microbiome being increasingly recognized for its potential influences on therapeutic response and clinical trials underway looking at “a healthy dietary pattern not just for prevention but survival.”

 

Diet and Probiotics After allo-HSCT

The patterns of microbiota disruption during allo-HSCT — a procedure that includes antibiotic administration, chemotherapy, and sometimes irradiation — are characterized by loss of diversity and the expansion of potentially pathogenic organisms, most commonly Enterococcus, said Peled.

This has been demonstrated across transplantation centers. In a multicenter, international study published in 2020, the patterns of microbiota disruption and their impact on mortality were similar across MSK and other transplantation centers, with higher diversity of intestinal microbiota associated with lower mortality.

Other studies have shown that Enterococcus domination alone (defined arbitrarily as > 30% of fecal microbial composition) is associated with graft vs host disease and higher mortality after allo-HSCT and that intestinal domination by Proteobacteria coincides temporally with BSIs, he said.

Autologous fecal microbiota transplantation (FMT) has been shown to largely restore the microbiota composition the patient had before antibiotic treatment and allo-HSCT, he said, making fecal sample banking and posttreatment FMT a potential approach for reconstituting the gut microbiome and improving outcomes.

But “lately we’ve been very interested in diet for modulating [harmful] patterns” in the microbiome composition, Peled said.

In the new study suggesting a role for sugar avoidance, published last year as a bioRxiv preprint, Peled and his colleagues collected real-time dietary intake data (40,702 food entries) from 173 patients hospitalized for several weeks for allo-HSCT at MSK and analyzed it alongside longitudinally collected fecal samples. They used a Bayesian mixed-effects model to identify dietary components that may correlate with microbial disruption.

“What jumped out as very predictive of a low diversity fecal sample [and expansion of Enterococcus] in the 2 days prior to collection was the interaction between antibiotics and the consumption of sweets” — foods rich in simple sugars, Peled said. The relationship between sugar and the microbiome occurred only during periods of antibiotic exposure.

“And it was particularly perplexing because the foods that fall into the ‘sweets’ category are foods we encourage people to eat clinically when they’re not feeling well and food intake drops dramatically,” he said. This includes foods like nutritional drinks or shakes, Italian ice, gelatin dessert, and sports drinks.

(In a mouse model of post-antibiotic Enterococcus expansion, Peled and his co-investigators then validated the findings and ruled out the impact of any reductions in fiber.)

In addition to possibly revising dietary recommendations for patients undergoing allo-HSCT, the findings raise the question of whether avoiding sugar intake while on antibiotics, in general, is a way to mitigate antibiotic-induced dysbiosis, he said.

To test the role of probiotics, Peled and colleagues collaborated with Seres Therapeutics on a phase 1b trial of an oral combination (SER-155) of 16 fermented strains “selected rationally,” he said, for their ability to decolonize gut pathogens, improve gut barrier function (in vitro), and reduce gut inflammation and local immune activation.

After a safety lead-in, patients were randomized to receive SER-155 (20) or placebo (14) three times — prior to transplant, upon neutrophil engraftment (with vancomycin “conditioning”), and after transplant. “The strains succeeded in grafting in the [gastrointestinal] GI tract…and some of them persisted all the way through to day 100,” Peled said.

The incidence of pathogen domination was substantially lower in the probiotic recipients compared to an MSK historical control cohort, and the incidence of BSIs was significantly lower compared to the placebo arm (10% vs 43%, respectively, representing a 77% relative risk reduction), he said.

 

Diet and Immunotherapy Response: Trials at MD Anderson

One of the first trials Daniel-MacDougall launched at MD Anderson on diet and the microbiome randomized 55 patients who were obese and had a history of colorectal cancer or precancerous polyps to add a cup of beans to their usual diet or to continue their usual diet without beans. There was a crossover at 8 weeks in the 16-week BE GONE trial; stool and fasting blood were collected every 4 weeks.

“Beans are a prebiotic super-house in my opinion, and they’re also something this population would avoid,” said Daniel-MacDougall, associate professor in the department of epidemiology at MD Anderson and faculty director of the Bionutrition Research Core and Research Kitchen.

“We saw a modest increase in alpha diversity [in the intervention group] and similar trends with microbiota-derived metabolites” that regressed when patients returned to their usual diet, she said. The researchers also documented decreases in proteomic biomarkers of intestinal and systemic immune and inflammatory response.

The impact of diet on cancer survival was shown in subsequent research, including an observational study published in Science in 2021 of patients with melanoma receiving immune checkpoint blockade (ICB) treatment. “Patients who consumed insufficient dietary fiber at the start of therapy tended to do worse [than those reporting sufficient fiber intake],” with significantly lower progression-free survival, Daniel-MacDougall said.

“And interestingly, when we looked at dietary fiber [with and without] probiotic use, patients who had sufficient fiber but did not take probiotics did the best,” she said. [The probiotics were not endorsed or selected by their physicians.]

Now, the researchers at MD Anderson are moving into “precision nutrition” research, Daniel-MacDougall said, with a phase 2 randomized, double-blind trial of high dietary fiber intake (a target of 50 g/d from whole foods) vs a healthy control diet (20 g/d of fiber) in patients with melanoma receiving ICB.

The study, which is underway, is a fully controlled feeding study, with all meals and snacks provided by MD Anderson and macronutrients controlled. Researchers are collecting blood, stool, and tumor tissue (if available) to answer questions about the microbiome, changes in systemic and tissue immunity, disease response and immunotherapy toxicity, and other issues.

Peled disclosed IP licensing and research support from Seres Therapeutics; consulting with Da Volterra, MaaT Pharma, and CSL Behring; and advisory/equity with Postbiotics + Research LLC and Prodigy Biosciences. Daniel-MacDougall reported having no disclosures.

A version of this article appeared on Medscape.com.

WASHINGTON — For years, oncologist Jonathan Peled, MD, PhD, and his colleagues at Memorial Sloan Kettering Cancer Center (MSKCC) in New York City have been documenting gut microbiota disruption during allogeneic hematopoietic stem cell transplantation (allo-HSCT) and its role in frequent and potentially fatal bloodstream infections (BSIs) in the first 100 days after transplant.

Modulating microbiome composition to improve outcomes after allo-HSCT for hematological malignancies is a prime goal, and at the Gut Microbiota for Health (GMFH) World Summit 2025, Peled shared two new findings.

In one study, his team found that sucrose can exacerbate antibiotic-induced microbiome injury in patients undergoing allo-HSCT — a finding that “raises the question of whether our dietary recommendations [for] allo-HSCT patients are correct,” said Peled, assistant attending at MSKCC, during a session on the gut microbiome and oncology.

And in another study, they found that a rationally designed probiotic formulation may help lower the incidence of bacterial BSIs. In December 2024, the probiotic formulation (SER-155, Seres Therapeutics, Inc.) was granted breakthrough therapy designation by the FDA.

With immunotherapies more broadly, researchers are increasingly looking at diet and modulation of the microbiome to improve both treatment tolerance and efficacy, experts said at the meeting convened by the AGA and the European Society of Neurogastroenterology and Motility.

“Cancer patients and caregivers are asking, ‘What should I eat?’” said Carrie Daniel-MacDougall, PhD, MPH, a nutritional epidemiologist at the University of Texas MD Anderson Cancer Center in Houston. “They’re not just focused on side effects — they want a good outcome for their treatment, and they’re exploring a lot of dietary strategies [for which there] is not a lot of evidence.”

Clinicians are challenged by the fact that “we don’t typically collect dietary data in clinical trials of cancer drugs,” leaving them to extrapolate from evidence-based diet guidelines for cancer prevention, Daniel-MacDougall said.

But “I think that’s starting to shift,” she said, with the microbiome being increasingly recognized for its potential influences on therapeutic response and clinical trials underway looking at “a healthy dietary pattern not just for prevention but survival.”

 

Diet and Probiotics After allo-HSCT

The patterns of microbiota disruption during allo-HSCT — a procedure that includes antibiotic administration, chemotherapy, and sometimes irradiation — are characterized by loss of diversity and the expansion of potentially pathogenic organisms, most commonly Enterococcus, said Peled.

This has been demonstrated across transplantation centers. In a multicenter, international study published in 2020, the patterns of microbiota disruption and their impact on mortality were similar across MSK and other transplantation centers, with higher diversity of intestinal microbiota associated with lower mortality.

Other studies have shown that Enterococcus domination alone (defined arbitrarily as > 30% of fecal microbial composition) is associated with graft vs host disease and higher mortality after allo-HSCT and that intestinal domination by Proteobacteria coincides temporally with BSIs, he said.

Autologous fecal microbiota transplantation (FMT) has been shown to largely restore the microbiota composition the patient had before antibiotic treatment and allo-HSCT, he said, making fecal sample banking and posttreatment FMT a potential approach for reconstituting the gut microbiome and improving outcomes.

But “lately we’ve been very interested in diet for modulating [harmful] patterns” in the microbiome composition, Peled said.

In the new study suggesting a role for sugar avoidance, published last year as a bioRxiv preprint, Peled and his colleagues collected real-time dietary intake data (40,702 food entries) from 173 patients hospitalized for several weeks for allo-HSCT at MSK and analyzed it alongside longitudinally collected fecal samples. They used a Bayesian mixed-effects model to identify dietary components that may correlate with microbial disruption.

“What jumped out as very predictive of a low diversity fecal sample [and expansion of Enterococcus] in the 2 days prior to collection was the interaction between antibiotics and the consumption of sweets” — foods rich in simple sugars, Peled said. The relationship between sugar and the microbiome occurred only during periods of antibiotic exposure.

“And it was particularly perplexing because the foods that fall into the ‘sweets’ category are foods we encourage people to eat clinically when they’re not feeling well and food intake drops dramatically,” he said. This includes foods like nutritional drinks or shakes, Italian ice, gelatin dessert, and sports drinks.

(In a mouse model of post-antibiotic Enterococcus expansion, Peled and his co-investigators then validated the findings and ruled out the impact of any reductions in fiber.)

In addition to possibly revising dietary recommendations for patients undergoing allo-HSCT, the findings raise the question of whether avoiding sugar intake while on antibiotics, in general, is a way to mitigate antibiotic-induced dysbiosis, he said.

To test the role of probiotics, Peled and colleagues collaborated with Seres Therapeutics on a phase 1b trial of an oral combination (SER-155) of 16 fermented strains “selected rationally,” he said, for their ability to decolonize gut pathogens, improve gut barrier function (in vitro), and reduce gut inflammation and local immune activation.

After a safety lead-in, patients were randomized to receive SER-155 (20) or placebo (14) three times — prior to transplant, upon neutrophil engraftment (with vancomycin “conditioning”), and after transplant. “The strains succeeded in grafting in the [gastrointestinal] GI tract…and some of them persisted all the way through to day 100,” Peled said.

The incidence of pathogen domination was substantially lower in the probiotic recipients compared to an MSK historical control cohort, and the incidence of BSIs was significantly lower compared to the placebo arm (10% vs 43%, respectively, representing a 77% relative risk reduction), he said.

 

Diet and Immunotherapy Response: Trials at MD Anderson

One of the first trials Daniel-MacDougall launched at MD Anderson on diet and the microbiome randomized 55 patients who were obese and had a history of colorectal cancer or precancerous polyps to add a cup of beans to their usual diet or to continue their usual diet without beans. There was a crossover at 8 weeks in the 16-week BE GONE trial; stool and fasting blood were collected every 4 weeks.

“Beans are a prebiotic super-house in my opinion, and they’re also something this population would avoid,” said Daniel-MacDougall, associate professor in the department of epidemiology at MD Anderson and faculty director of the Bionutrition Research Core and Research Kitchen.

“We saw a modest increase in alpha diversity [in the intervention group] and similar trends with microbiota-derived metabolites” that regressed when patients returned to their usual diet, she said. The researchers also documented decreases in proteomic biomarkers of intestinal and systemic immune and inflammatory response.

The impact of diet on cancer survival was shown in subsequent research, including an observational study published in Science in 2021 of patients with melanoma receiving immune checkpoint blockade (ICB) treatment. “Patients who consumed insufficient dietary fiber at the start of therapy tended to do worse [than those reporting sufficient fiber intake],” with significantly lower progression-free survival, Daniel-MacDougall said.

“And interestingly, when we looked at dietary fiber [with and without] probiotic use, patients who had sufficient fiber but did not take probiotics did the best,” she said. [The probiotics were not endorsed or selected by their physicians.]

Now, the researchers at MD Anderson are moving into “precision nutrition” research, Daniel-MacDougall said, with a phase 2 randomized, double-blind trial of high dietary fiber intake (a target of 50 g/d from whole foods) vs a healthy control diet (20 g/d of fiber) in patients with melanoma receiving ICB.

The study, which is underway, is a fully controlled feeding study, with all meals and snacks provided by MD Anderson and macronutrients controlled. Researchers are collecting blood, stool, and tumor tissue (if available) to answer questions about the microbiome, changes in systemic and tissue immunity, disease response and immunotherapy toxicity, and other issues.

Peled disclosed IP licensing and research support from Seres Therapeutics; consulting with Da Volterra, MaaT Pharma, and CSL Behring; and advisory/equity with Postbiotics + Research LLC and Prodigy Biosciences. Daniel-MacDougall reported having no disclosures.

A version of this article appeared on Medscape.com.

WASHINGTON — For years, oncologist Jonathan Peled, MD, PhD, and his colleagues at Memorial Sloan Kettering Cancer Center (MSKCC) in New York City have been documenting gut microbiota disruption during allogeneic hematopoietic stem cell transplantation (allo-HSCT) and its role in frequent and potentially fatal bloodstream infections (BSIs) in the first 100 days after transplant.

Modulating microbiome composition to improve outcomes after allo-HSCT for hematological malignancies is a prime goal, and at the Gut Microbiota for Health (GMFH) World Summit 2025, Peled shared two new findings.

In one study, his team found that sucrose can exacerbate antibiotic-induced microbiome injury in patients undergoing allo-HSCT — a finding that “raises the question of whether our dietary recommendations [for] allo-HSCT patients are correct,” said Peled, assistant attending at MSKCC, during a session on the gut microbiome and oncology.

And in another study, they found that a rationally designed probiotic formulation may help lower the incidence of bacterial BSIs. In December 2024, the probiotic formulation (SER-155, Seres Therapeutics, Inc.) was granted breakthrough therapy designation by the FDA.

With immunotherapies more broadly, researchers are increasingly looking at diet and modulation of the microbiome to improve both treatment tolerance and efficacy, experts said at the meeting convened by the AGA and the European Society of Neurogastroenterology and Motility.

“Cancer patients and caregivers are asking, ‘What should I eat?’” said Carrie Daniel-MacDougall, PhD, MPH, a nutritional epidemiologist at the University of Texas MD Anderson Cancer Center in Houston. “They’re not just focused on side effects — they want a good outcome for their treatment, and they’re exploring a lot of dietary strategies [for which there] is not a lot of evidence.”

Clinicians are challenged by the fact that “we don’t typically collect dietary data in clinical trials of cancer drugs,” leaving them to extrapolate from evidence-based diet guidelines for cancer prevention, Daniel-MacDougall said.

But “I think that’s starting to shift,” she said, with the microbiome being increasingly recognized for its potential influences on therapeutic response and clinical trials underway looking at “a healthy dietary pattern not just for prevention but survival.”

 

Diet and Probiotics After allo-HSCT

The patterns of microbiota disruption during allo-HSCT — a procedure that includes antibiotic administration, chemotherapy, and sometimes irradiation — are characterized by loss of diversity and the expansion of potentially pathogenic organisms, most commonly Enterococcus, said Peled.

This has been demonstrated across transplantation centers. In a multicenter, international study published in 2020, the patterns of microbiota disruption and their impact on mortality were similar across MSK and other transplantation centers, with higher diversity of intestinal microbiota associated with lower mortality.

Other studies have shown that Enterococcus domination alone (defined arbitrarily as > 30% of fecal microbial composition) is associated with graft vs host disease and higher mortality after allo-HSCT and that intestinal domination by Proteobacteria coincides temporally with BSIs, he said.

Autologous fecal microbiota transplantation (FMT) has been shown to largely restore the microbiota composition the patient had before antibiotic treatment and allo-HSCT, he said, making fecal sample banking and posttreatment FMT a potential approach for reconstituting the gut microbiome and improving outcomes.

But “lately we’ve been very interested in diet for modulating [harmful] patterns” in the microbiome composition, Peled said.

In the new study suggesting a role for sugar avoidance, published last year as a bioRxiv preprint, Peled and his colleagues collected real-time dietary intake data (40,702 food entries) from 173 patients hospitalized for several weeks for allo-HSCT at MSK and analyzed it alongside longitudinally collected fecal samples. They used a Bayesian mixed-effects model to identify dietary components that may correlate with microbial disruption.

“What jumped out as very predictive of a low diversity fecal sample [and expansion of Enterococcus] in the 2 days prior to collection was the interaction between antibiotics and the consumption of sweets” — foods rich in simple sugars, Peled said. The relationship between sugar and the microbiome occurred only during periods of antibiotic exposure.

“And it was particularly perplexing because the foods that fall into the ‘sweets’ category are foods we encourage people to eat clinically when they’re not feeling well and food intake drops dramatically,” he said. This includes foods like nutritional drinks or shakes, Italian ice, gelatin dessert, and sports drinks.

(In a mouse model of post-antibiotic Enterococcus expansion, Peled and his co-investigators then validated the findings and ruled out the impact of any reductions in fiber.)

In addition to possibly revising dietary recommendations for patients undergoing allo-HSCT, the findings raise the question of whether avoiding sugar intake while on antibiotics, in general, is a way to mitigate antibiotic-induced dysbiosis, he said.

To test the role of probiotics, Peled and colleagues collaborated with Seres Therapeutics on a phase 1b trial of an oral combination (SER-155) of 16 fermented strains “selected rationally,” he said, for their ability to decolonize gut pathogens, improve gut barrier function (in vitro), and reduce gut inflammation and local immune activation.

After a safety lead-in, patients were randomized to receive SER-155 (20) or placebo (14) three times — prior to transplant, upon neutrophil engraftment (with vancomycin “conditioning”), and after transplant. “The strains succeeded in grafting in the [gastrointestinal] GI tract…and some of them persisted all the way through to day 100,” Peled said.

The incidence of pathogen domination was substantially lower in the probiotic recipients compared to an MSK historical control cohort, and the incidence of BSIs was significantly lower compared to the placebo arm (10% vs 43%, respectively, representing a 77% relative risk reduction), he said.

 

Diet and Immunotherapy Response: Trials at MD Anderson

One of the first trials Daniel-MacDougall launched at MD Anderson on diet and the microbiome randomized 55 patients who were obese and had a history of colorectal cancer or precancerous polyps to add a cup of beans to their usual diet or to continue their usual diet without beans. There was a crossover at 8 weeks in the 16-week BE GONE trial; stool and fasting blood were collected every 4 weeks.

“Beans are a prebiotic super-house in my opinion, and they’re also something this population would avoid,” said Daniel-MacDougall, associate professor in the department of epidemiology at MD Anderson and faculty director of the Bionutrition Research Core and Research Kitchen.

“We saw a modest increase in alpha diversity [in the intervention group] and similar trends with microbiota-derived metabolites” that regressed when patients returned to their usual diet, she said. The researchers also documented decreases in proteomic biomarkers of intestinal and systemic immune and inflammatory response.

The impact of diet on cancer survival was shown in subsequent research, including an observational study published in Science in 2021 of patients with melanoma receiving immune checkpoint blockade (ICB) treatment. “Patients who consumed insufficient dietary fiber at the start of therapy tended to do worse [than those reporting sufficient fiber intake],” with significantly lower progression-free survival, Daniel-MacDougall said.

“And interestingly, when we looked at dietary fiber [with and without] probiotic use, patients who had sufficient fiber but did not take probiotics did the best,” she said. [The probiotics were not endorsed or selected by their physicians.]

Now, the researchers at MD Anderson are moving into “precision nutrition” research, Daniel-MacDougall said, with a phase 2 randomized, double-blind trial of high dietary fiber intake (a target of 50 g/d from whole foods) vs a healthy control diet (20 g/d of fiber) in patients with melanoma receiving ICB.

The study, which is underway, is a fully controlled feeding study, with all meals and snacks provided by MD Anderson and macronutrients controlled. Researchers are collecting blood, stool, and tumor tissue (if available) to answer questions about the microbiome, changes in systemic and tissue immunity, disease response and immunotherapy toxicity, and other issues.

Peled disclosed IP licensing and research support from Seres Therapeutics; consulting with Da Volterra, MaaT Pharma, and CSL Behring; and advisory/equity with Postbiotics + Research LLC and Prodigy Biosciences. Daniel-MacDougall reported having no disclosures.

A version of this article appeared on Medscape.com.