title: Predictive performance of urine neutrophil gelatinase-associated lipocalin for dialysis requirement and death following cardiac surgery in neonates and infants.
abstract: OBJECTIVE
  Urine neutrophil gelatinase-associated lipocalin (uNGAL) has been shown to accurately predict and allow early detection of AKI, as assessed by an increase in serum creatinine in children and adults. The present study explores the accuracy of uNGAL for the prediction of severe AKI-related outcomes in neonates and infants undergoing cardiac surgery: dialysis requirement and/or death within 30 days.
  
  
  METHODS
  Prospective, observational cohort study conducted in a tertiary referral pediatric cardiac intensive care unit, including 75 neonates and 125 infants undergoing surgery with cardiopulmonary bypass between August 1, 2010, and May 31, 2011. Urine samples were collected before surgery and at median of five time points within 48 hours of bypass. Urine NGAL was quantified as absolute concentration, creatinine-normalized concentration, and absolute excretion rate, and a clusterization algorithm was applied to the individual uNGAL kinetics. The accuracy for the prediction of the outcome was assessed using receiver-operating characteristic areas, likelihood ratios, diagnostic odds ratios, net reclassification index, integrated reclassification improvement, and number needed to screen.
  
  
  RESULTS
  A total of 1176 urine samples were collected. Of all patients, 8% required dialysis and 4% died. Three clusters of uNGAL kinetics were identified, including patients with significantly different outcomes. The uNGAL level peaked between 1 and 3 hours of bypass and remained high in half of all patients who required dialysis or died. The uNGAL levels measured within 24 hours of bypass accurately predicted the outcome and performed best after normalization to creatinine, with varying cutoffs according to the time elapsed since bypass. The number needed to screen to correctly identify the risk of dialysis or death in one patient varied between 1.5 and 2.6 within 12 hours of bypass.
  
  
  CONCLUSIONS
  uNGAL is a valuable predictive tool of dialysis requirement and death in neonates and infants with AKI after cardiac surgery.
authors.affiliation: Department of Anesthesiology and Critical Care and , †Department of Biochemistry, Necker-Enfants Malades Hospital, Assistance Publique-Hôpitaux de Paris, France, ‡Unité de Recherche Clinique, CIC Centre Necker Cochin, Assistance Publique-Hôpitaux de Paris, France;, §Institut National de la Santé et de la Recherche Médicale, Paris Sud University and Paris Descartes University, Paris, France;, ‖Paul Brousse Hospital, Assistance Publique, Hôpitaux de Paris, France;, ¶Paris Descartes University, Paris, France, *Department of Anesthesiology and Critical Care, Georges Pompidou European Hospital, Assistance Publique-Hôpitaux de Paris, France.
authors.forename: Mirela
authors.initials: M
authors.lastname: Bojan
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Vicca
authors.forename: Vanessa
authors.initials: V
authors.lastname: Lopez-Lopez
authors.forename: Agnes
authors.initials: A
authors.lastname: Mogenet
authors.forename: Philippe
authors.initials: P
authors.lastname: Pouard
authors.forename: Bruno
authors.initials: B
authors.lastname: Falissard
authors.forename: Didier
authors.initials: D
authors.lastname: Journois
mesh_terms: D058186:Acute Kidney Injury / Q000175:diagnosis / Q000401:mortality / Q000628:therapy* / Q000652:urine*; D000209:Acute-Phase Proteins / Q000652:urine*; D000367:Age Factors; D019540:Area Under Curve; D015415:Biomarkers / Q000652:urine; D006348:Cardiac Surgical Procedures / Q000009:adverse effects* / Q000401:mortality; D016009:Chi-Square Distribution; D016000:Cluster Analysis; D003404:Creatinine / Q000652:urine; D017052:Hospital Mortality; D006801:Humans; D007223:Infant; D007226:Infant Mortality; D007231:Infant, Newborn; D015278:Intensive Care Units, Pediatric; D016013:Likelihood Functions; D000071068:Lipocalin-2; D054834:Lipocalins / Q000652:urine*; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011518:Proto-Oncogene Proteins / Q000652:urine*; D012372:ROC Curve; D012042:Registries; D006435:Renal Dialysis / Q000009:adverse effects / Q000401:mortality; D012307:Risk Factors; D012720:Severity of Illness Index; D062606:Tertiary Care Centers; D013997:Time Factors; D016896:Treatment Outcome; D016482:Urinalysis
chemical_list: D000209:Acute-Phase Proteins; D015415:Biomarkers; C489506:LCN2 protein, human; D000071068:Lipocalin-2; D054834:Lipocalins; D011518:Proto-Oncogene Proteins; D003404:Creatinine