title: Detection of acute kidney injury in premature asphyxiated neonates by serum neutrophil gelatinase-associated lipocalin (sNGAL)--sensitivity and specificity of a potential new biomarker.
abstract: BACKGROUND
  Acute kidney injury (AKI) is common in neonatal intensive care units (NICU). In recent years, every effort is made for early detection of AKI. Our hypothesis was that serum neutrophil gelatinase-associated lipocalin (sNGAL) may be a reliable screening test for early diagnosis of AKI in premature neonates after perinatal asphyxia. Therefore, our aim was to assess the diagnostic accuracy of sNGAL for AKI in premature asphyxiated neonates.
  
  
  METHODS
  AKI was defined in the third day of life (DOL 3) as a serum creatinine (sCr) increase ≥26.5 μmol/L from baseline (the lowest previous sCr). According to the increase of sCr, AKI patients were divided in AKIN1 (sCr increase up to 1.9 baseline) and AKIN2 (sCr increase from 2.0 to 2.9 baseline). sNGAL levels were measured on DOL 1, 3 and 7.
  
  
  RESULTS
  AKI was diagnosed in 73 (0.676) of 108 enrolled premature asphyxiated neonates. Sixty one patients (0.836) were classified in AKIN1 and 12 patients (0.164) in AKIN2. sNGAL reached the maximal concentrations on DOL 1 within 4 hours after admission to NICU, being higher in AKI compared with no-AKI group (160.8±113.1 vs. 87.1±81.6; P<0.001) as well as in AKIN2 compared with AKIN1 group (222.8±112.9 vs. 147.8±109.9; P<0.001). The best areas under the receiver operating characteristic curves (AUC) for prediction of AKI were 0.72 [95% (0.62-0.80) P<0.001] on DOL1 at 2h and 0.72 [95% (0.63-0.80) P<0.001] at 4th hour after admission respectively. The corresponding sNGAL cutoff concentrations were 84.87 ng/mL (sensitivity 69.0% and specificity 71.9%) and 89.43 ng/mL (sensitivity 65.7% and specificity 74.3%).
  
  
  CONCLUSIONS
  In premature asphyxiated neonates sNGAL measured within the first 4 hours of DOL 1 is predictive of the occurrence and severity of AKI. Therefore, plasma levels of NGAL may be used for early diagnosis of AKI in these patients.
authors.affiliation: Institute of Neonatology, Neonatal Intensive Care Unit, Belgrade, Serbia.
authors.forename: Biljana
authors.initials: B
authors.lastname: Pejović
authors.affiliation: School of Medicine, Institute of Medical Statistics and Informatics, University of Belgrade, Belgrade, Serbia.
authors.forename: Jelena
authors.initials: J
authors.lastname: Erić-Marinković
authors.affiliation: School of Medicine, University of Belgrade, Belgrade, Serbia.
authors.forename: Marija
authors.initials: M
authors.lastname: Pejović
authors.affiliation: Faculty of Pharmacy, University of Belgrade, Belgrade, Serbia.
authors.forename: Jelena
authors.initials: J
authors.lastname: Kotur-Stevuljević
authors.affiliation: School of Medicine, University of Belgrade, University Children's Hospital, Department of Nephrology, Belgrade, Serbia.
authors.forename: Amira
authors.initials: A
authors.lastname: Peco-Antić
mesh_terms: D058186:Acute Kidney Injury / Q000097:blood / Q000175:diagnosis* / Q000209:etiology; D000209:Acute-Phase Proteins; D019540:Area Under Curve; D001238:Asphyxia Neonatorum / Q000097:blood / Q000150:complications*; D015415:Biomarkers / Q000097:blood; D003430:Cross-Sectional Studies; D042241:Early Diagnosis; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D007235:Infant, Premature, Diseases / Q000097:blood* / Q000175:diagnosis; D007363:Intensive Care Units, Neonatal; D000071068:Lipocalin-2; D054834:Lipocalins / Q000097:blood*; D008297:Male; D018579:Patient Selection; D011518:Proto-Oncogene Proteins / Q000097:blood*; D012372:ROC Curve; D012680:Sensitivity and Specificity; D055771:Serbia
chemical_list: D000209:Acute-Phase Proteins; D015415:Biomarkers; C489506:LCN2 protein, human; D000071068:Lipocalin-2; D054834:Lipocalins; D011518:Proto-Oncogene Proteins
keywords: acute kidney injury; biomarker; premature neonates; serum neutrophil gelatinase-associated lipocalin