Diabetic nephropathy and proliferative retinopathy with normal glucose tolerance

A 61-yr-old man presented with the nephrotic syndrome and normal oral glucose tolerance. Renal biopsy showed the nodular (Kimmelstiel-Wilson) and diffuse glomerulosclerosis lesions characteristic of diabetes. Direct ophthalmoscopy and fluorescein angiography demonstrated a picture of advanced proliferative diabetic retinopathy. The patient had no history of diabetes mellitus and upon testing had normal glucose values in response to an oral glucose tolerance test. Insulin response to an intravenous glucose tolerance test was abnormally low. It is concluded that the nodular glomerulosclerosis lesions and proliferative retinopathy, thought to be specific for diabetes mellitus, may present in the absence of either overt clinical diabetes or impaired glucose tolerance.