하시모토 갑상선염 환자에서의 인슐린자가면역증후군 1예

Abstract

Insulin autoimmune syndrome (IAS) is characterized by fasting hypoglycemia, endogenous hyperinsulinemia,and the presence of autoantibodies to insulin or insulin receptor in patients that have never been exposedto exogenous insulin. This syndrome is occasionally accompanied by several autoimmune disorders. There isno reported case of concurrent IAS with Hashimoto's thyroiditis. A 52-year-old female was diagnosed withHashimoto’s thyroiditis and was treated with 25 μg/d levothyroxine for 3 years. Recently, she experiencedrecurrent fasting hypoglycemic symptoms that disappeared rapidly with a carbohydrate-rich diet, although shehad no history of diabetes or insulin use. Blood analysis showed hypoglycemia and elevated serum levels ofinsulin and C-peptide. Imaging studies did not reveal a mass lesion in the pancreas, and selectivecalcium-stimulated venous sampling also gave a negative result. However, anti-insulin antibody titer was highand assay for anti-insulin receptor antibody was positive. Here, we report a case of IAS concomitant withHashimoto’s thyroiditis.