Insulin autoimmune syndrome: An analysis of clinical features, following up data, and review of literature

Abstract

Objective To analyze the clinical characteristics and prognosis of patients with insulin autoimmune syndrome (IAS) and to get better understanding of IAS by literatures reviewing.Methods Nine cases of IAS who were diagnosed in the General Hospital of the People's Liberation Army from 2001 to 2011 were analyzed.Results All patients had hypoglycemic syndrome and episodes of hypoglycemia during both postprandial and fasting states.Most cases (8/9) were accompanied with autoimmune diseases,including 6 cases of Graves' disease treated with methimazole.The biochemical data showed extremely elevated serum insulin level (9/9) during hypoglycemic episode.For most patients,the tests of insulin autoantibodies were positive (7/9) while results of imaging examinations were negative(8/9).After removal of possible offending medications and with diet treatment,hypoglycemic episodes were ameliorated in 5 of 9 cases.For severe patients,acarbose (1/9) and prednisone (3/9)therapy were useful.During the period of follow-up,four cases experienced no episode of hypoglycemia and 3 cases with markedly reduced episodes.Conclusions IAS is characterized by hypoglycemic episodes,elevated blood insulin levels,and positive insulin autoantibodies.It is strongly related with autoimmune disease and is able to be induced by methimazole.Most patients undergo remission after diet treatment,drug withdrawal,and oral prednisone. Key words: Insulin autoimmune syndrome; Hypoglycemia; Insulin autoantibodies