An Unusual Form of Diabetes Mellitus in Ataxia Telangiectasia

Abstract

Five of eight patients with documented ataxia telangiectasia had an unusual form of diabetes mellitus, characterized by marked hyperglycemia, resistance to ketosis, absence of glycosuria and markedly elevated plasma insulin levels in response to the administration of glucose or tolbutamide. Moreover, the blood glucose response to both exogenous and endogenous insulin was decreased, signifying insulin resistance similar to that found in pregnancy, acromegaly and obesity. In addition, the five subjects with diabetes had evidence of hepatic disease, which has not previously been reported in ataxia telangiectasia. Although the etiology of the hepatic dysfunction is not known, the immunologic deficiency commonly present in this disease may be responsible. Carbohydrate intolerance and the hypersecretion of insulin have been attributed to hepatic disease in some patients, or to certain lesions of the central nervous system in others, but it is not known if the diabetic state in ataxia telangiectasia results from dysfunction of either of these systems.