Abnormal glucose tolerance in patients with chronic glomerulonephritis without renal failure

An oral glucose tolerance test and an assay of insulin receptor activity were performed in patients with chronic glomerulonephritis (CGN) to elucidate the aberration of glucose metabolism in such patients. Ninety of 123 patients with CGN without renal failure showed abnormal glucose tolerance, including 72.6% with IgA nephropathy, 81% with benign recurrent hematuria, 87% with chronic proliferative glomerulonephritis, 100% with membranoproliferative glomerulonephritis, and 80.0% with membranous nephropathy. Insulin responses in CGN patients during oral glucose tolerance tests showed lower levels of basal insulin and significantly higher levels after 90, 120, and 180 min compared with those of normal controls. The binding of radiolabeled insulin to blood mononuclear cells in 22 CGN patients with abnormal glucose tolerance was significantly (P = 0.0023) decreased in comparison with 5 normal controls. However, plasma obtained from such patients showed no significant (P = 0.4761) inhibition of the binding of insulin to normal mononuclear cells. It was concluded that glucose tolerance capacity was impaired in 80.4% of patients with CGN without renal failure. Such impairment of glucose metabolism might be due to decreased activity of insulin receptors on cells in CGN patients.