Urinary excretion of N-acetyl-β-D-glucosaminidase (NAG) by children with upper or lower urinary tract infections

Differentiation of upper and lower urinary tract infections (UTI) in infancy is limited by the poor sensitivity and specificity of non-invasive methods. Subjective symptoms and some objective tests which may be helpful in adults are often unreliable in children. Enzymuria as an index of renal damage has been studied in different diseases and the excretion of some enzymes has been found to be significantly increased in adults and children with upper UTI. We therefore investigated urinary excretion of the lysosomal enzyme N-acetyl-β-D-glucosaminidase (NAG) in 2 groups of patients in whom the site of infection had been diagnosed according to commonly accepted criteria. 36 children (11 mth-10 yr old) were included in this study.