title: Failure of renal biomarkers to predict worsening renal function in high-risk patients presenting with oliguria.
abstract: OBJECTIVE
  Oliguria is a common symptom in critically ill patients and puts patients in a high risk category for further worsening renal function (WRF). We performed this study to explore the predictive value of biomarkers to predict WRF in oliguric intensive care unit (ICU) patients.
  
  
  METHODS
  Single-center prospective observational study. ICU patients were included when they presented a first episode of oliguria. Plasma and urine biomarkers were measured: plasma and urine neutrophil gelatinase-associated lipocalin (pNGAL and uNGAL), urine α1-microglobulin, urine γ-glutamyl transferase, urine indices of tubular function, cystatin C, C terminal fragment of pro-arginine vasopressin (CT-ProAVP), and proadrenomedullin (MR-ProADM).
  
  
  RESULTS
  One hundred eleven patients formed the cohort, of whom 41 [corrected] had worsening renal function. Simplified Acute Physiology Score (SAPS) II was 41 (31-51). WRF was associated with increased mortality (hazard ratio 8.65 [95 % confidence interval (CI) 3.0-24.9], p = 0.0002). pNGAL, MR-ProADM, and cystatin C had the best odds ratio and area under the receiver-operating characteristic curve (AUC-ROC: 0.83 [0.75-0.9], 0.82 [0.71-0.91], and 0.83 [0.74-0.90]), but not different from serum creatinine (Screat, 0.80 [0.70-0.88]). A clinical model that included age, sepsis, SAPS II, and Screat had AUC-ROC of 0.79 [0.69-0.87]; inclusion of pNGAL increased the AUC-ROC to 0.86 (p = 0.03). The category-free net reclassification index improved with pNGAL (total net reclassification index for events to higher risk 61 % and nonevents to lower 82 %).
  
  
  CONCLUSIONS
  All episodes of oliguria do not carry the same risk. No biomarker further improved prediction of WRF compared with Screat in this selected cohort of patients at increased risk defined by oliguria.
authors.affiliation: Department of Anesthesiology and Critical Care and SMUR and Burn Unit, Assistance Publique-Hopitaux de Paris, AP-HP, GH St-Louis-Lariboisière, University of Paris 7 Denis Diderot, 1 rue Claude Vellefaux, 75010, Paris, France, matthieu.m.legrand@gmail.com.
authors.forename: Matthieu
authors.initials: M
authors.lastname: Legrand
authors.forename: Aurélien
authors.initials: A
authors.lastname: Jacquemod
authors.forename: Etienne
authors.initials: E
authors.lastname: Gayat
authors.forename: Corinne
authors.initials: C
authors.lastname: Collet
authors.forename: Veronique
authors.initials: V
authors.lastname: Giraudeaux
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Launay
authors.forename: Didier
authors.initials: D
authors.lastname: Payen
mesh_terms: D000209:Acute-Phase Proteins / Q000652:urine; D053607:Adrenomedullin / Q000652:urine; D000368:Aged; D000510:Alpha-Globulins / Q000652:urine; D015415:Biomarkers / Q000097:blood / Q000652:urine; D055316:Cystatin C / Q000652:urine; D018450:Disease Progression; D005260:Female; D006020:Glycopeptides / Q000652:urine; D006801:Humans; D007362:Intensive Care Units; D007677:Kidney Function Tests; D000071068:Lipocalin-2; D054834:Lipocalins / Q000097:blood / Q000652:urine; D008297:Male; D008875:Middle Aged; D009846:Oliguria / Q000097:blood* / Q000652:urine*; D063305:Organ Dysfunction Scores; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011498:Protein Precursors / Q000652:urine; D011518:Proto-Oncogene Proteins / Q000097:blood / Q000652:urine; D051437:Renal Insufficiency / Q000097:blood* / Q000628:therapy / Q000652:urine*; D005723:gamma-Glutamyltransferase / Q000097:blood / Q000652:urine
chemical_list: D000209:Acute-Phase Proteins; D000510:Alpha-Globulins; D015415:Biomarkers; D055316:Cystatin C; D006020:Glycopeptides; C489506:LCN2 protein, human; D000071068:Lipocalin-2; D054834:Lipocalins; D011498:Protein Precursors; D011518:Proto-Oncogene Proteins; C016001:alpha-1-microglobulin; C048197:copeptins; C088633:proadrenomedullin; D053607:Adrenomedullin; D005723:gamma-Glutamyltransferase