Acute kidney injury in preterm neonates with ≤30 weeks of gestational age and its risk factors

BACKGROUND: Acute kidney injury (AKI), an abrupt decline in kidney function, is a challenging diagnosis among preterm infants due to some specific features of this population. The aim of this study was to determine the risk factors of developing AKI and the predictive factors for its severity in preterm neonates with less than 31 weeks of gestational age. METHODS: All neonates with less than 31 weeks of gestational age, admitted in our NICU between January 2012 and December 2015, were included. Maternal and neonatal records about demographics, placental abnormalities, perinatal and neonatal period and evolution in NICU, as well as electrolytic analysis and serum creatinine and urea values during their hospitalization were retrospectively collected and analyzed. RESULTS: A total of 106 neonates were included. Of those, 24 were diagnosed with AKI, resulting in a prevalence of 22.6%, and 82 were used as controls. Gestational age (OR=0.39; 95% CI=0.2-0.76; P=0.006), congenital malformations (OR=36.93; 95%CI=2.48-550.59; P=0.009), vasoactive drugs (OR=27.06; 95%CI=3.58-204.45; P=0.001), nonsteroidal anti-inflammatory drugs (OR=9.61; 95%CI=1.78-51.73; P=0.008) and sepsis (OR=7.78; 95%CI=1.32-46.04; P=0.024) were found to be independent risk factors. Cardiac surgery was a predictive factor for AKI severity (OR=25; 95%CI=2.09-298.29; P=0.011). The mortality rate in the AKI group was 41.7%. CONCLUSIONS: AKI in preterm neonates is an important feature that contributes to increase the mortality in NICUs. Thus, it is crucial to know its risk factors to establish prompt diagnosis and prevention and, in this way, be able to improve the prognosis.