Celiac Disease and Autoimmune Thyroid Disease: The Two Peas in a Pod

Celiac disease (CD) is a small intestinal inflammatory disease commonly seen in the Western population. It has been observed that patients with monoglandular and polyglandular autoimmunity have a higher prevalence of celiac disease. Hashimoto's thyroiditis (HT) and Graves' disease (GD), which mainly constitute the autoimmune thyroid diseases (AITD), characterized by lymphocytic infiltration of the thyroid parenchyma, are noted to be frequently associated with celiac disease. The fundamental mechanism of this frequent coexistence is thought to be a shared genetic background. Due to the subclinical nature of the celiac disease, the diagnosis is often missed or made coincidentally during screening. The rising prevalence of the celiac disease among AITD patients has urged researchers to investigate the link between the two. We reviewed the most recent and relevant literature on the intriguing relationship between celiac disease and thyroid autoimmunity. The objectives of this article were to study the shared genetic background, the incidence of CD in AITD, the effect of a gluten-free diet on AITD, and the need for routine screening of CD in AITD patients.