Indices of renal tubular function in perinatal asphyxia

Abstract

Aims-To determine and compare two urinary indices of renal tubular function, N-acetyl-glucosaminidase (NAG) and β2-microglobulin (β2M), in healthy term neonates and babies with perinatal asphyxia. Methods-In a prospective case-control study using asphyxiated (n=35) and normal control (n=55) infants, urinary NAG and β2M were assayed at 24-48 hours of life, 4- 6 days, and 4-6 weeks. Results-NAG and β2M were significantly increased at 24-48 hours and 4-6 days in the asphyxiated infants compared with the controls. Increased NAG values reflect the degree of perinatal asphyxia more than do β2M. Gentamicin also increased NAG excretion, but to a lesser extent than did perinatal asphyxia. Conclusions-NAG (+/- β2M) may be a useful marker of perinatal asphyxia. Urinary NAG concentrations correlate with the severity of perinatal asphyxia.