Changes of Urinary Neutrophil Gelatinase-associated Lipocalin and Kidney Injury Molecule-1 in Children with Acute Kidney Injury

Objective To determine the function of neutrophil gelatinase-associated lipocalin(NGAL) and kidney injury molecule-1(KIM-1) in children acute kidney injury(AKI) prediction.Methods A prospective single-center evaluation of urinary biomarkers was performed in a cohort of children who presented to Shengjing Hospital Pediatric Clinic and Emergency center from June 2009 to December 2010.Patients were included if the physician ordered a serum creatinine and had been done serum creatinine within one year.Patients with a known diagnosis of chronic kidney disease were excluded.Five mL of urine was obtained for assessment of NGAL and KIM-1 by ELISA method.Patients were classified by the pediatric modified RIFLE(pRIFLE) criteria for AKI.The primary diagnosis and length of hospitalization were also recorded.Results A total of 552 patients were enrolled in the study,316 patients were hospitalized,59 patients were diagnosed AKI.Patients with AKI had a significantly elevated mean urinary NGAL and KIM-1 level compared with normal kidney function patients.AKI-F patients had the highest value of urinary NGAL and KIM-1 and significant statistical difference was found when comparing with normal groups(329.1±366.2,13.9±12.7,and 1129.0±1018.7,280.2±218.6,P 0.001).These values were superior to those for NAG and serum creatinine.Some patients with AKI-R and AKI-I had normal value of serum creatinine and significantly elevated urinary NGAL and KIM-1.The length of hospitalization for the children was correlated with the severity of AKI.Conclusion Pediatric AKI is not only caused by kidney disease but also by other diseases.Urinary NGAL and KIM-1 were significantly elevated in the children with early stage AKI,which may serve well to detect AKI accurately even in cases where serum creatinine levels are normal.