The relation between urinary NAG and glomerular lesions studied in association with isozyme A and NAG/protein ratio and effects of walking

Abstract

Relations between urinary NAG and glomerular lesions were studied. The incidence of elevated urinary NAG levels in normal school childron was only 0.8% (5/575) in contrast to 65.5% (19/29) of patients with prolif erative glomerular lesions. Isozyme A of urinary NAG was 75.0% in normal controls with age over 5 years old, and decreased in patients with nephrotic syndrome with positive urinary protein (p<0.001) and chronic glomerulonephritis (but statistically not significant), presumably because of filtered serum protein which had lower % of isozyme A. Decreased NAG/protein ratio was also noted for the same reason as the decreased isozyme A. The patients who had normal urinary NAG levels despite the presence of proliferative renal glomerular lesions showed increased urinary NAG excretion after standing, walking or routine daily activities in upright position for 3-4 hours.