Proteinuria and enzymuria in non-insulin-dependent diabetics

Urine albumin, alpha 1- and beta 2-microglobulins, retinol-binding protein (RBP) and N-acetyl-beta-D-glucosaminidase (NAG) were measured in early morning urine samples from 99 non-insulin-dependent diabetic (NIDDM) patients receiving ambulatory care at a primary health care polyclinic. Elevated NAG levels were found in 90% of diabetics regardless of the duration of their disease. Almost half (43.4%) of the subjects had microalbuminuria. Over a third of the subjects without albuminuria had elevated alpha 1-microglobulin levels in their urine. The proportion of subjects with elevated alpha 1 levels increased significantly with the presence of albumin, poor glycaemic control and increased duration of disease. These findings suggest that proximal tubular as well glomerular dysfunction coexist in the NIDDM patients studied.