Insulin autoimmune syndrome in a patient with methimazole and carbimazole-treated Graves' disease: a case report.
Insulin autoimmune syndrome (IAS) includes fasting or reactive hypoglycemia, hyperinsulinemia and the presence of insulin-binding antibodies in patients who have never been exposed to exogenous insulin. The report concerns a 34-year-old male patient with Graves' disease who had history of having taken methimazole for two months, without any consequence, 4 years previously. However, when methimazole was again administered for three weeks followed by a week of carbimazole, the patient suffered hypoglycemia 4 times during the next 4 weeks. He denied history of diabetes mellitus (DM), of taking any oral hypoglycemic agent or of having received insulin injection. Laboratory data showed total serum insulin level > 320 microU/mL, free insulin 55 microU/mL and insulin antibody 88.3%. Oral glucose tolerance test (OGTT) revealed DM pattern. Since the patient had history of allergy to anti-thyroid drugs before this event, so he was treated with radioiodine (131I). There was no episode of hypoglycemic attack during 15 months of follow-up.
Lu
C C
CC
Department of Medicine, National Yang-Ming University, Taipei, Taiwan, R.O.C.
Lee
J K
JK
Lam
H C
HC
Yang
C Y
CY
Han
T M
TM
D000328:Adult; D001327:Autoimmune Diseases / Q000209:etiology*; D002231:Carbimazole / Q000009:adverse effects*; D006111:Graves Disease / Q000188:drug therapy*; D006801:Humans; D007328:Insulin / Q000276:immunology*; D008297:Male; D008713:Methimazole / Q000009:adverse effects*
D007328:Insulin; D008713:Methimazole; D002231:Carbimazole