To avoid false-negative results in celiac testing, the patient should be on what diet during evaluation?

To avoid false-negative results in celiac testing, the patient should be on what diet during evaluation?

• A. Gluten-containing diet
• B. Gluten-free diet
• C. Low FODMAP diet
• D. Ketogenic diet

Answer: (A)

Continuing to eat gluten during evaluation keeps the disease in its active state, so the immune system produces the antibodies and the intestinal changes that the tests are looking for. Serology for celiac disease (like anti-tTG and anti-endomysial antibodies) rises in response to gluten exposure, and small-bowel damage from celiac disease is driven by gluten. If you remove gluten, these antibodies can fall and the mucosa can heal, which can make the tests appear falsely negative even if celiac disease is present. That’s why testing is done while the patient is on a gluten-containing diet. If someone has already started a gluten-free diet, the tests may not reflect true disease status, and clinicians might reintroduce gluten for a period before testing or use genetic testing as supplemental information, since HLA-DQ2/DQ8 positivity supports the possibility of celiac disease but does not confirm it on its own. The other dietary patterns don’t specifically affect the celiac-related immune response in the way that gluten exposure does, so they’re not appropriate for avoiding false negatives.

Continuing to eat gluten during evaluation keeps the disease in its active state, so the immune system produces the antibodies and the intestinal changes that the tests are looking for. Serology for celiac disease (like anti-tTG and anti-endomysial antibodies) rises in response to gluten exposure, and small-bowel damage from celiac disease is driven by gluten. If you remove gluten, these antibodies can fall and the mucosa can heal, which can make the tests appear falsely negative even if celiac disease is present. That’s why testing is done while the patient is on a gluten-containing diet.

If someone has already started a gluten-free diet, the tests may not reflect true disease status, and clinicians might reintroduce gluten for a period before testing or use genetic testing as supplemental information, since HLA-DQ2/DQ8 positivity supports the possibility of celiac disease but does not confirm it on its own. The other dietary patterns don’t specifically affect the celiac-related immune response in the way that gluten exposure does, so they’re not appropriate for avoiding false negatives.