The Development and Characterization of Diabetes Mellitus in Cystic Fibrosis

Abstract

The association of cystic fibrosis with chemical glucose intolerance and overt diabetes mellitus is becoming increasingly more common. It is noty yet clear whether this results from genetic interwinning or pancreatic islet cell destruction or both. 200 children with cystic fibrosis over 7 years of age were screened for glucose intolerance. Factors as sex, age, severity of cystic fibrosis and family history of diabetes mellitus were analyzed. 48 of the 200 were classified as glucose intolerant (1-h blood sugar over 175 mg%). 3-h oral glucose tolerance tests were performed on these 48. Significant impairment of glucose tolerance was demonstrated in 85% (values greater than 97th percentile of normal established by PICKENS et al.). No relation was established as to sex, age or ideal body weight. Two and one half years later, these 48 were re-studied. Six had developed overt insulin requiring diabetes melitus. These were evaluated by blood glucose measurements and serum immunoreactive insulin and growth hormone assays following oral and intravenous glucose, intravenous tolbutamide and intramuscular glucagon tolerance tests. Findings compatible with a severe insulin deficient state were obtained.