The Role of Urinary N-acetyl-beta-glucosaminidase in Diagnosis of Kidney Diseases

N-acetyl-beta-D-glucosaminidase (NAG) is a lysosomal enzyme present in the proximal convoluted tubules of the kidneys that may be used as a marker of proximal tubular damage and nephrotoxicity. An abnormal urinary NAG excretion has been reported in different kinds of renal disorders such as acute kidney injury, urinary tract infection, vesicoureteral reflux; diabetes mellitus; nephrotic syndrome; glomerulonephritis; hypertension; perinatal asphyxia; heavy metals poisoning; drug nephrotoxicity, renal allograft rejection; and heart failure. This paper provides an overview of the diagnostic value of urinary NAG in the nephrourology field.