Serum NGAL and copeptin levels as predictors of acute kidney injury in asphyxiated neonates

Background

Acute kidney injury (AKI) is the most common complication of perinatal asphyxia. Recent research indicates that serum neutrophil gelatinase-associated lipocalin (NGAL) is an early marker for AKI, but there are the lacks of data about its use in term neonates with perinatal asphyxia.

Methods

A prospective cohort study was conducted on 43 term neonates. Umbilical cord blood and 24 h after birth serum NGAL, copeptin, creatinine, and molality were measured in all asphyxiated and controls neonates.

Results

During the study period, 8 of asphyxiated nenates (18.6 %) suffered from AKI, while 35 newborns have no signs of AKI and 30 healthy infants. We did not observe any differences in creatinine and copeptin levels, as well as serum osmolality in all three investigated groups (AKI, no-AKI, and controls) in cord blood, and 24 h after birth. Serum NGAL levels in umbilical cord blood were significantly higher in the AKI group (174.3 ng/mL) compared with no-AKI (88.5 ng/mL, p = 0.01) and control groups (28.5 ng/mL, p < 0.001), and 24 h after birth (respectively, AKI 152.5 ng/mL vs no-AKI 74.9 ng/mL, p = 0.02 vs controls 39.1 ng/mL, p < 0.001). NGAL concentration showed a strong negative correlation to umbilical artery pH (Rho = ?0.42, p = 0.04), base excess (Rho = ?0.31, p = 0.03), and Apgar score in 1st min (Rho = ?0.41, p = 0.02) and 5th min of life (Rho = ?0.20, p = 0.001). ROC curve analysis demonstrated a good predictive value for NGAL levels (>140.7 ng/mL) which allows to diagnose AKI in asphyxiated patients with 88.9 % sensitivity (95 % CI 75–95 %) and 95.0 % specificity (95 % CI 76–99 %).

Conclusion

NGAL seems to be a promising marker, even in subclinical AKI in neonates, due to its high specificity, but copeptin did not meet expectations.