Serologic testing in celiac disease: Practical guide for clinicians.

OBJECTIVE To address the questions and challenges commonly faced by primary care physicians when ordering serologic tests for celiac disease (CD) and provide practical clinical tips to help in the interpretation of test results. SOURCES OF INFORMATION MEDLINE was searched from 2000 to 2015 for English-language guidelines on the diagnosis and management of CD published by professional gastroenterological organizations. MAIN MESSAGE To screen patients for CD, measurement of the immunoglobulin A (IgA) tissue transglutaminase antibody is the preferred test. Total serum IgA level should be measured to exclude selective IgA deficiency and to avoid false-negative test results. Patients with positive serologic test results should be referred to a gastroenterologist for endoscopic small intestinal biopsies to confirm the diagnosis. Testing for human leukocyte antigens DQ2 and DQ8 can help exclude the diagnosis. A gluten-free diet should not be started before confirming the diagnosis of CD. CONCLUSION Serologic testing is very useful for screening patients with suspected CD. Early diagnosis is essential to prevent complications of CD.