Renal failure, comorbidity and mortality in preterm infants.

OBJECTIVE

To evaluate patient characteristics and risk factors for mortality in critically ill preterm infants with renal failure, with a special focus on infants with extremely low birth weight.

DESIGN

Retrospective cohort study with five year follow-up of all premature infants who were treated in the neonatal intensive care unit in 2002 and developed postnatal serum creatinine > or =1.5 mg/dl and/or urine output <1 ml/kg per h.

SETTING

Tertiary Care University Hospital of the Medical University of Vienna

PATIENTS: Sixteen of 359 premature infants (9 boys, 7 girls) fulfilled the inclusion criteria for renal failure. Their median gestational age was 30 weeks (range 24-36) with a median birth weight of 811.5 g (range 588-2662).

MEASUREMENTS AND MAIN

RESULTS

The most common causes of renal failure were sepsis and ischemic events. All infants were managed conservatively with corrections of fluids, electrolytes and acidosis, including medication with diuretics and dopamine. Eleven infants with renal failure (69%) died in multiorgan failure. Infants with low urine output, higher scores for failed organs or low birth weight were significantly more likely to die. Infants with very low birth weights had higher scores for failed organs (all P < 0.05).

CONCLUSION

Oliguria/anuria, multiorgan failure and immaturity were significant risk factors for mortality in preterm infants with renal failure. Further studies and/or more registry data are needed to determine whether these infants died with or from renal failure, and whether dialysis would improve outcome in this special population.