The purpose of this study was to determine the prevalence and types of acute renal failure in asphyxiated full-term neonates and to evaluate the accuracy of an asphyxia morbidity score in predicting acute renal failure. Neonates admitted to one institution from 1990 through 1993 with a gestational age > or = 36 weeks and 5-min Apgar score < or = 6, without congenital malformations or sepsis, were studied retrospectively for acute renal failure in the 1st week of life. Acute renal failure was defined as serum creatinine > 1.5 mg/dl (133 mumol/l) with normal maternal renal function. Nonoliguric renal failure was defined as renal failure with urine output > 1 ml/kg per hour after the 1st day. An asphyxia morbidity scoring system was used to distinguish severe from moderate asphyxia. The score ranged from 0 to 9 and was based upon fetal heart rate, Apgar score at 5 min, and base deficit in the 1st h of life. The score for severe asphyxia was defined as 6-9 and for moderate asphyxia as 1-5. Sixty-six neonates fulfilled study criteria. Acute renal failure was present in 20 of 33 (61%) infants with severe asphyxia scores and 0 of 33 with moderate asphyxia scores (P < 0.0001). Acute renal failure was nonoliguric in 12 of 20 (60%), oliguric in 5 of 20 (25%) and anuric in 3 of 20 (15%). In conclusion 1) acute renal failure occurred in 61% of infants with severe asphyxia, 2) acute renal failure associated with severe asphyxia was predominantly nonoliguric and 3) an asphyxia morbidity score, which can be determined at 1 h of age, predicted acute renal failure in full-term infants with 100% sensitivity and 72% specificity.