INS and Hypoglycemia: Insulin autoimmune syndrome (IAS), also known as Hirata's disease or insulin autoimmune hypoglycemia, is a rare autoimmune disorder which can cause fasting and/or postprandial hypoglycemia with high serum concentrations of total immunoreactive insulin and the presence of insulin autoantibodies in those with no prior exposure to exogenous insulin.[1–3] The disease was first reported in Japan by Hiram in 1970,[4] and 400 cases have since been reported.