American Board of Internal Medicine (ABIM) Certification Practice Exam

When should serologic testing for celiac disease ideally be conducted?

1. While the patient is on a gluten-free diet

2. During hospitalization

3. While the patient is consuming gluten

4. As part of routine health screening

The correct answer is: While the patient is consuming gluten

The ideal time to conduct serologic testing for celiac disease is while the patient is consuming gluten. This is crucial because the tests for celiac disease, such as tissue transglutaminase antibodies (tTG-IgA) and immunoglobulin A (IgA) endomysial antibodies (EMA), are designed to detect antibodies that the immune system produces in response to gluten intake. If a patient is on a gluten-free diet, the levels of these antibodies may return to normal or decrease, which could lead to false-negative test results. This means the tests might not accurately reflect the presence of celiac disease. Testing during hospitalization can occur for various reasons, but it is not necessarily the appropriate time for celiac disease evaluations unless the patient is actively consuming gluten during that stay. Routine health screening does not typically include celiac testing unless there are specific risk factors or symptoms present that suggest the disease. Therefore, for accurate serological results, ensuring that the patient is consuming gluten prior to testing is essential.