Insulin resistance in a young man with cystic fibrosis
M. E. Geffner, B. M. Lippe, R. M. Itami, S. A. Kaplan, B. K. Gillard, S. R. Levin and I. L. Taylor
An 18-year-old man had cystic fibrosis (CF) and insulin-resistant
carbohydrate intolerance characterized by (1) obesity, basal
hyperinsulinemia, and hyperglucagonemia; (2) impaired oral glucose
tolerance; (3) hyperinsulinemia in response to oral and intravenous (IV)
administration of glucose and to IV administration of tolbutamide; (4)
exaggerated gastric inhibitory polypeptide secretion following orally
administered glucose; and (5) diminished sensitivity to insulin
administered IV compared with other patients with CF. Both parents also
demonstrate basal and stimulated hyperinsulinemia in response to orally
administered glucose. The long-term outlook for patients with CF is
improving, and more patients are surviving childhood. Thus, it should be
recognized that an insulin-resistant form of carbohydrate intolerance may
develop in patients with CF with obesity and/or genetic risk factors.