Universal celiac screening lacks evidence, U.S. panel finds

There is not enough evidence to encourage or discouragedoctors from testing all their patients for celiac disease, according to a U.S.government-backed panel.

Even when close relatives have been diagnosed with the autoimmune condition,there isn't enough evidence to say screening should always be done.

The new statement from the U.S. Preventive Services Task Force (USPSTF)applies to adults without celiac disease symptoms, which can include abdominalpain, bloating, gas, diarrhea, anemia and weight loss.

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"I think if individuals are concerned or they're having symptoms, theyshould talk to their doctor about it," said Dr. Alex Krist, who is a USPSTFmember and an associate professor of family medicine and population health atVirginia Commonwealth University in Richmond.

In people with celiac disease, consuming the gluten protein in wheat, rye orbarley triggers an autoimmune response that harms the lining of the smallintestine. As a result, people with the condition are advised to go on agluten-free diet.

The USPSTF writes in JAMA that between 0.40 and 0.95 per cent of people inthe U.S. have celiac disease. The condition is more common among non-Hispanicwhites, people with a family history of celiac disease and people with otherautoimmune conditions, such as Type 1diabetes.

Recommendations of other organizations vary, but some like the AmericanCollege of Gastroenterology and the North American Society of PediatricGastroenterology do recommend testing certain individuals who are at anincreased risk for the condition, such asthose with immediate family with celiac disease.

Family doctors in Canada are also advised that since celiac disease can be present with mild or "atypical symptoms, a high index of suspicion is required."

"The term 'asymptomatic'can be tricky," said Dr. MohsinRashid, a gastroenterology professor at Dalhousie University in Halifax. "Many of these people once diagnosed and start a gluten-free diet realize that they were really not that 'asymptomatic.' The symptoms can be very mild and non-specific and people may not seek medical help," he added in an email to CBC News.

Testing for celiac disease starts out with a blood sample, Krist told Reuters Health. If the blood test is positive, a biopsy of the small intestinemay be needed to confirm the results.

"We don't want to subject patients to that type of test if it's not going tohelp them," he said.

The USPSTF says more research on screening people at an increased risk ofceliac disease who are not showing symptoms is needed.

Additionally, Krist said, research is needed on the course of the diseaseamong people living with the condition but not showing symptoms known assilent or asymptomatic celiac disease.

In an editorial, Drs. Rok Seon Choung and Joseph Murray from the Mayo Clinicin Rochester, Minnesota agree there is a lack of evidence supporting universaltesting for celiac disease in people without symptoms.

"Recognizing that most celiac disease is undetected and may present withdiverse symptoms, it is reasonable that clinicians should have a low thresholdfor testing for celiac disease, especially in high-risk populations such asthose with an affected family member or Type 1 diabetes mellitus," they add.

Krist said the USPSTF regularly evaluates the evidence on its statements andrecommendations. Depending on evidence, the statement may change during a futureupdate.

Until then, he said, people should bring up their concerns to their doctors.

The new statement was previously published as a draft in May 2016.