Occurrence of Thyroid Autoimmunity in Children with Type 1 Diabetes Mellitus

Introduction: It is well known that patients suffering from an autoimmune disease are more prone to develop another one, too. The authors have previously shown frequent occurrence of celiac disease in patients with type 1 diabetes mellitus compared to the background population. Autoimmune thyroid disease, the most common autoimmune disorder, associated with type 1 diabetes mellitus, generally occurs after the manifestation of diabetes, in the second decade of life. The aim of the study was to investigate the prevalence of thyroid autoimmunity as well as the frequency of autoimmune thyroid disease in patients with type 1 diabetes mellitus. Its aim was also to compare the prevalence of autoimmune thyroid disease in patients with type 1 diabetes mellitus and in those with type 1 diabetes mellitus and celiac disease. Methods: Screening was performed in 268 patients with type 1 diabetes mellitus alone and in 48 children with type 1 diabetes mellitus and celiac disease, with the aid of anti-peroxidase and anti-thyroglobulin antibody. In case of autoantibody positivity testing of thyroid function and ultrasonography confirmed the autoimmune thyroid disease. According to the results, the frequency of autoantibody positivity was significantly higher in diabetic patients suffering from celiac disease (type 1 diabetes mellitus: 43 (16%), type 1 diabetes mellitus + celiac disease: 16 (33.3%, p < 0.01). Hypothyroidism due to thyroiditis was also more prevalent in patients with type 1 diabetes mellitus and celiac disease. Conclusions: Due to increased risk, the authors emphasize the need of frequent screening for autoimmune thyroid disorder in patients with type 1 diabetes mellitus and celiac disease.