Retrospective evaluation of frequency and related risk factors of autoimmune thyroiditis, glutene-sensitive enteropathy and other autoimmune diseases in children withTYPE 1 diabetes mellitus diagnosed at Uludağ University Pediatric Endocrinology outpatient clinics between 2009-2019

Type 1 Diabetes Mellitus (Type 1 DM) is an autoimmune chronic disorder that occurs with the complex interaction of immune, genetic and environmental factors, progressing with absolute insulin deficiency as a result of damage to pancreatic beta cells. In this study, the files of 725 patients diagnosed with type 1 DM between 2009-2019 in Uludağ University Faculty of Medicine, Pediatric Endocrinology Outpatient Clinic, GAD-65 antibody, anti-insulin antibody, antithyroid antibodies, tissue transglutaminase antibody, c-peptide and insulin at the time of diagnosis. levels, hormonal evaluations, biochemical and demographic characteristics and anthropometric measurements were examined retrospectively. Autoimmune thyroid disease was detected in 3% of the patients, and anti-TPO were positive in 95.20% and anti-TG were found in 94.10% of them. Among the patients included in the study, the rate of those with celiac disease was 2.90% (n=21). One patient had both celiac and autoimmune thyroid disease. Autoimmune thyroid disease, Sjögren's syndrome and autoimmune hepatitis were seen in one patient, celiac and autoimmune hepatitis in one patient, and celiac disease and vitiligo together in one patient. It has been observed that the frequency of autoimmune thyroiditis and celiac disease is increasing in patients with type 1 DM. These two diseases should be considered in the routine follow-up of patients with type 1 DM. For this, the best and quickest evaluation method is the serological study of autoantibodies. Key Words: Type 1 DM, autoimmune thyroiditis, celiac disease.