Serum neutrophil gelatinase-associated lipocalin (NGAL) as a marker of acute kidney injury in critically ill children with septic shock

OBJECTIVE: To validate serum neutrophil gelatinase-associated lipocalin (NGAL) as an early biomarker for acute kidney injury in critically ill children with septic shock. DESIGN: Observational cohort study. SETTING: Fifteen North American pediatric intensive care units (PICUs). PATIENTS: A total of 143 critically ill children with systemic inflammatory response syndrome (SIRS) or septic shock and 25 healthy controls. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Serum NGAL was measured during the first 24 hrs of admission to the PICU. Acute kidney injury was defined as a blood urea nitrogen concentration >100 mg/dL, serum creatinine >2 mg/dL in the absence of preexisting renal disease, or the need for dialysis. There was a significant difference in serum NGAL between healthy children (median 80 ng/mL, interquartile ratio [IQR] 55.5-85.5 ng/mL), critically ill children with SIRS (median 107.5 ng/mL, IQR 89-178.5 ng/mL), and critically ill children with septic shock (median 302 ng/mL, IQR 151-570 ng/mL; p < .001). Acute kidney injury developed in 22 of 143 (15.4%) critically ill children. Serum NGAL was significantly increased in critically ill children with acute kidney injury (median 355 ng/mL, IQR 166-1322 ng/mL) compared with those without acute kidney injury (median 186 ng/mL, IQR 98-365 ng/mL; p = .009). CONCLUSIONS: Serum NGAL is a highly sensitive but nonspecific predictor of acute kidney injury in critically ill children with septic shock. Further validation of serum NGAL as a biomarker of acute kidney injury in this population is warranted.