Serologic Testing for Celiac Disease in Graves' Hyperthyroidism: Should We Act Early?

Area of Science:

• Endocrinology
• Gastroenterology
• Immunology

Background:

• Autoimmune thyroid disease (AITD) screening for celiac disease (CD) is common practice.
• Optimal timing for CD screening in Graves' disease (GD) patients remains unclear.
• This study investigates celiac antibody persistence after achieving euthyroidism in GD patients.

Purpose of the Study:

• To determine if positive celiac antibodies in Graves' disease patients persist after achieving a euthyroid state.
• To assess the impact of thyroid status on celiac antibody seropositivity.
• To inform best practices for CD screening in GD management.

Main Methods:

• 35 patients with GD were screened for CD using IgG/IgA antigliadin antibodies (AGA), IgA endomysial antibody (IgA-EMA), and IgA tissue transglutaminase antibody (IgA anti-tTG).
• Antibody levels were reevaluated once patients achieved euthyroidism through antithyroid therapy.
• Small intestine biopsy was offered to patients with persistent antibody positivity.

Main Results:

• Initial screening revealed varying positive rates for different celiac antibodies (e.g., IgA-AGA 17%, IgG-AGA 26%).
• Upon achieving euthyroidism, IgA-AGA, IgG-AGA, and IgA-EMA became negative in previously positive patients.
• Two patients maintained positive IgA anti-tTG antibodies despite euthyroidism; their duodenal biopsies showed normal villi/crypts.

Conclusions:

• False seropositivity for celiac antibodies can occur in patients with Graves' thyrotoxicosis.
• CD screening in GD patients is recommended only after euthyroidism is attained.
• Deferring celiac antibody testing until euthyroidism avoids potential false positives and unnecessary follow-up.