Celiac disease is a multisystem autoimmune disorder in genetically predisposed adults and children that is triggered by dietary gluten. Patients with celiac disease who ingest gluten can develop inflammatory damage to their small intestines, which can cause gastrointestinal and nongastrointestinal illness.
Studies of the United States population found an estimated prevalence of celiac disease in adults ranging from 0.4 percent to 0.95 percent. The prevalence is higher than average in non-Hispanic whites, patients with a family history of celiac disease and those with additional autoimmune conditions.
- The U.S. Preventive Services Task Force (USPSTF) released its first-ever draft recommendation statement on May 3 on screening asymptomatic patients for celiac disease.
- This draft recommendation does not apply to patients with symptoms of celiac disease such as diarrhea, abdominal pain and unexplained weight loss.
- The USPSTF is providing an opportunity for public comment on the two draft documents until May 30.
In an effort to better understand the disease, the U.S. Preventive Services Task Force (USPSTF) released its first-ever draft recommendation statement(www.uspreventiveservicestaskforce.org) and draft evidence review(www.uspreventiveservicestaskforce.org) on May 3 on screening asymptomatic patients for celiac disease and concluded evidence was insufficient to assess the balance of benefits and harms of the practice. This is an "I" recommendation.(www.uspreventiveservicestaskforce.org)
This draft recommendation does not apply to patients with symptoms of celiac disease such as diarrhea, abdominal pain and unexplained weight loss.
"More evidence on screening for celiac disease is needed before the task force can recommend for or against screening people who don't have any signs or symptoms of the condition," said USPSTF member Alex Krist, M.D., M.P.H., in a news release.(www.uspreventiveservicestaskforce.org) "In the face of unclear evidence, physicians should use their clinical judgment when deciding whom to screen."
The USPSTF highlighted areas of research on celiac disease that could better inform future recommendations for screening patients, specifically, research into
- the effectiveness of targeted screening in patients at increased risk for celiac disease;
- the accuracy of serological markers in asymptomatic patients, particularly those with risk factors;
- the effect of treatment of celiac disease in asymptomatic patients who have positive blood tests for celiac disease; and
- clinical outcomes such as changes in health and quality of life in people who are screened versus people who are not screened.
Scope of Review
The USPSTF reviewed the evidence on the accuracy of screening in asymptomatic adults, adolescents and children; the potential benefits and harms of screening versus not screening, as well as targeted versus universal screening; and the benefits and harms of treatment of screen-detected celiac disease. For questions regarding the benefits and harms of screening and treatment, outcomes of interest included morbidity, mortality and quality of life.
The task force also reviewed contextual information on the prevalence of celiac disease among patients without overt symptoms and the natural history of subclinical or silent celiac disease.
A recent good-quality systematic review on the accuracy of diagnostic tests for celiac disease, which included studies of patients with symptoms or those in whom symptom status was not described, found high strength of evidence that the tissue transglutaminase (tTG) immunoglobulin A (IgA) test is associated with high (greater than 90 percent) sensitivity and specificity and endomysial antibody (EMA) IgA tests are associated with high specificity, based on consistent results from prior systematic reviews and new studies.
The systematic review included only two studies reporting diagnostic accuracy in asymptomatic patients. These cross-sectional studies, which were both conducted outside the United States, found lower sensitivity and specificity for the tTG and EMA IgA tests (sensitivity, 57 percent to 71 percent; specificity, 83 percent to 98 percent) compared to studies that were not restricted to asymptomatic patients.
The USPSTF said it did not review evidence on nonceliac gluten sensitivity because the condition is defined based on the presence of symptoms rather than diagnostic tests, and it is not known to lead to health complications associated with celiac disease.
The USPSTF is providing an opportunity for public comment on this draft recommendation statement(www.uspreventiveservicestaskforce.org) and draft evidence review(www.uspreventiveservicestaskforce.org) until May 30.
The AAFP is reviewing the USPSTF's draft recommendation and will release its own recommendation after the task force publishes its final recommendation statement.