title: Urinary biomarkers and renal recovery in critically ill patients with renal support.
abstract: OBJECTIVE
  Despite significant advances in the epidemiology of acute kidney injury (AKI), prognostication remains a major clinical challenge. Unfortunately, no reliable method to predict renal recovery exists. The discovery of biomarkers to aid in clinical risk prediction for recovery after AKI would represent a significant advance over current practice.
  
  
  METHODS
  We conducted the Biological Markers of Recovery for the Kidney study as an ancillary to the Acute Renal Failure Trial Network study. Urine samples were collected on days 1, 7, and 14 from 76 patients who developed AKI and received renal replacement therapy (RRT) in the intensive care unit. We explored whether levels of urinary neutrophil gelatinase-associated lipocalin (uNGAL), urinary hepatocyte growth factor (uHGF), urinary cystatin C (uCystatin C), IL-18, neutrophil gelatinase-associated lipocalin/matrix metalloproteinase-9, and urine creatinine could predict subsequent renal recovery.
  
  
  RESULTS
  We defined renal recovery as alive and free of dialysis at 60 days from the start of RRT. Patients who recovered had higher uCystatin C on day 1 (7.27 versus 6.60 ng/mg·creatinine) and lower uHGF on days 7 and 14 (2.97 versus 3.48 ng/mg·creatinine; 2.24 versus 3.40 ng/mg·creatinine). For predicting recovery, decreasing uNGAL and uHGF in the first 14 days was associated with greater odds of renal recovery. The most predictive model combined relative changes in biomarkers with clinical variables and resulted in an area under the receiver-operator characteristic curve of 0.94.
  
  
  CONCLUSIONS
  We showed that a panel of urine biomarkers can augment clinical risk prediction for recovery after AKI.
authors.affiliation: 604 Scaife Hall, Department of Critical Care Medicine, University of Pittsburgh, 3550 Terrace Street, Pittsburgh, PA 15261, USA.
authors.forename: Nattachai
authors.initials: N
authors.lastname: Srisawat
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Wen
authors.forename: Minjae
authors.initials: M
authors.lastname: Lee
authors.forename: Lan
authors.initials: L
authors.lastname: Kong
authors.forename: Michele
authors.initials: M
authors.lastname: Elder
authors.forename: Melinda
authors.initials: M
authors.lastname: Carter
authors.forename: Mark
authors.initials: M
authors.lastname: Unruh
authors.forename: Kevin
authors.initials: K
authors.lastname: Finkel
authors.forename: Anitha
authors.initials: A
authors.lastname: Vijayan
authors.forename: Mohan
authors.initials: M
authors.lastname: Ramkumar
authors.forename: Emil
authors.initials: E
authors.lastname: Paganini
authors.forename: Kai
authors.initials: K
authors.lastname: Singbartl
authors.forename: Paul M
authors.initials: PM
authors.lastname: Palevsky
authors.forename: John A
authors.initials: JA
authors.lastname: Kellum
mesh_terms: D058186:Acute Kidney Injury / Q000503:physiopathology / Q000628:therapy* / Q000652:urine*; D000209:Acute-Phase Proteins / Q000652:urine; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000652:urine*; D016009:Chi-Square Distribution; D003404:Creatinine / Q000652:urine; D016638:Critical Illness; D055316:Cystatin C / Q000652:urine; D005260:Female; D017228:Hepatocyte Growth Factor / Q000652:urine; D006801:Humans; D020382:Interleukin-18 / Q000652:urine; D007668:Kidney / Q000503:physiopathology*; D000071068:Lipocalin-2; D054834:Lipocalins / Q000652:urine; D016015:Logistic Models; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000652:urine; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011518:Proto-Oncogene Proteins / Q000652:urine; D012372:ROC Curve; D020127:Recovery of Function; D017582:Renal Replacement Therapy; D013997:Time Factors; D016896:Treatment Outcome; D014481:United States
chemical_list: D000209:Acute-Phase Proteins; D015415:Biomarkers; C525030:CST3 protein, human; D055316:Cystatin C; C066855:HGF protein, human; D020382:Interleukin-18; C489506:LCN2 protein, human; D000071068:Lipocalin-2; D054834:Lipocalins; D011518:Proto-Oncogene Proteins; D017228:Hepatocyte Growth Factor; D003404:Creatinine; D020780:Matrix Metalloproteinase 9