Postasphyxial renal injury in newborns as a prognostic factor of neurological outcome.

OBJECTIVE: To estimate if an acute postasphyxial renal injury in newborns could indicate a neurological outcome.

METHODS: We conducted a prospective clinical trial on 50 full-term newborns with 5-minute Apgar score <7 (asphyxiated group) and a control group of 50 full-term newborns with 5-min Apgar score ≥ 7 (non-asphyxiated group). Renal function was assessed on the third day of life by serum values of creatinine, cystatin C and β2-microglobulin (β2M) and glomerular filtration rate (GFR). All newborns had brain and renal ultrasonography at early stages and were followed by Amiel-Tison Neurological Assassment (ATNA) throughout the first year of life.

RESULTS: Mean GFR was significantly lower in asphyxiated than in non-asphyxiated group (22.08 ± 6.66 ml/min/1, 73 m(2) versus 35.42 ± 2.26 ml/min/1, 73 m(2); p < 0.001) and serum values of creatinine, cystatin C and β2M were significantly higher (1.13 versus 0.66 mg/dl; 3.92 versus 1.52 mg/l; 1.53 versus 0.99 mg/l; p < 0.001). In asphyxiated group ATNA results throughout the first year of life significantly correlated with renal function (p < 0.01). A correlation of ATNA with Apgar score at 5 min, Sarnat and Sarnat staging of hypoxic ischemic encephalopathy and brain and renal ultrasonography has also been significant (p < 0.01).

CONCLUSIONS: Our study showed a significant correlation between early impairment of renal function due to neonatal asphyxia with neurological outcome at the end of the first year of life.