N-acetyl-beta-glucosaminidase and beta 2-microglobulin. Their urinary excretion in patients with renal parenchymal disease

Abstract

The urinary excretion of N-acetyl-.beta.-glucosaminidase (NAG) and .beta.2-microglobulin (.beta.2M) was studied in 43 patients with various forms of renal parenchymal disease. Patients with membranous nephropathy, membranoproliferative glomerulonephritis, focal segmental glomerulosclerosis, obstructive pyelonephritis, nephrosclerosis, and minimal change nephropathy generally had urinary NAG and .beta.2M levels more than 3 SDs above those seen in normal subjects. Patients with progressive renal disease averaged higher NAG and .beta.2M urinary levels than those with the same renal lesion and stable function. Since elevated urinary levels of NAG and .beta.2M suggest renal tubular injury or dysfunction, tubulointerstitial involvement may exist in a wide variety of renal diseases.