Studies of Muscle Capillary Basement Membranes in Normal Subjects, Diabetic, and Prediabetic Patients

Abstract

measurement of muscle capillary basement mem-branes by electron microscopic examination of needle biopsies of the quadriceps muscle. With this procedure it has been possible to obtain an ob-jective evaluation of the significance of capillary basement membrane hypertrophy in diabetic mi-croangiopathy. The results *of such studies of muscle capillary basement membrane thickness in 50 normal, 51 diabetic, and 30 prediabetic pa-tients have demonstrated the following. First, that the average capillary basement membrane width of diabetic patients is over twice that of normal subjects; moreover, such basement membrane thickening is a very constant finding among overtly diabetic patients, in that approximately 98%o of individual diabetic subjects demonstrated this lesion. The degree of basement membrane thickening in diabetic patients is, however, un-related to age, weight, severity, or duration of diabetes. Second, capillary basement membrane hypertrophy has been found in approximately 50%o of patients who are genetically prediabetic but who have not yet demonstrated evidence of the manifest carbohydrate disturbances of dia-betes mellitus. Third, in contrast to the results obtained in genetically diabetic patients, subjects with severe hyperglycemia due to causes othe