Normalization of insulin and glucagon secretion in ketosis-resistant diabetes mellitus with prolonged diet therapy.

Glucose tolerance and insulin and glucagon secretion were examined sequentially during 6 months of calorie and carbohydrate restriction in an obese, recent-onset, ketosis-resistant diabetic adult. The subject was then followed for 9 additional months, during which some weight was regained. Fasting plasma glucose levels returned to normal after 6 week of calorie restriction and remained normal during periods of carbohydrate refeeding. Normalization of 2-h plasma glucose concentrations after a standard oral carbohydrate load required 5 months, and glucose disposal after an iv glucose load did not return to normal until the end of the study. Insulin secretion in response to oral glucose reached maximal levels during the first months of weight reduction and then decreased as glucose tolerance continued to improve. Acute phase insulin release in response to iv glucose gradually increased throughout the study. Glucagon stimulation by iv arginine and suppression by iv glucose also returned to normal levels slowly over several months. Abnormalities in glucose tolerance and glucoregulatory hormone secretion of ketosis-resistant diabetes are totally reversible with prolonged dietary therapy. Reduction in tissue resistance to the action of insulin also appeared to be of major importance in the recovery of normal glucose tolerance in this subject.