title: Performance of urinary NGAL and L-FABP in predicting acute kidney injury and subsequent renal recovery: a cohort study based on major surgeries.
abstract: BACKGROUND
  Acute kidney injury (AKI) is a frequent complication of major surgery. The current study evaluated the power of two biomarkers [urinary neutrophil gelatinase-associated lipocalin (NGAL) and liver-type fatty acid binding protein (L-FABP)] to detect the occurrence of AKI and to predict the recovery from renal dysfunction in a major surgery cohort.
  
  
  METHODS
  In this prospective study, 199 patients undergoing major surgery were enrolled. Urinary samples collected from participants before surgery, and 0, 4, and 12 h and 1, 2, 7, and 14 days after surgery were tested for NGAL and L-FABP.
  
  
  RESULTS
  Thirty-seven (18.6%) subjects developed AKI. Urinary NGAL and L-FABP were significantly increased from the time surgery was completed (p<0.05). The peak levels of NGAL and L-FABP occurred 12 and 4 h postoperatively (16.4- and 172.0-fold compared to baseline) in AKI group, respectively. The area under the receiver operating characteristic (ROC) curve (AUC) in NGAL (at 12 h), L-FABP (at 4 h), the most predictive model (NGAL at 12 h+L-FABP at 4 h), and the best combination at the same time point (12 h) was 0.83 [95% confidence interval (CI), 0.74-0.91], 0.85 (95% CI 0.77-0.93), 0.94 (95% CI 0.89-0.98), and 0.91 (95% CI 0.85-0.97), respectively. However, the largest AUC of single and combined biomarkers for predicting non-recovery after AKI only reached 0.70.
  
  
  CONCLUSIONS
  Urinary NGAL and L-FABP can be used to detect AKI and combining NGAL and L-FABP may improve the diagnostic performance; however, NGAL and L-FABP may be poor predictors for renal recovery after AKI.
authors.forename: Xian-Fei
authors.initials: XF
authors.lastname: Zeng
authors.forename: Jun-Min
authors.initials: JM
authors.lastname: Li
authors.forename: Yun
authors.initials: Y
authors.lastname: Tan
authors.forename: Zhu-Feng
authors.initials: ZF
authors.lastname: Wang
authors.forename: Yong
authors.initials: Y
authors.lastname: He
authors.forename: Jiang
authors.initials: J
authors.lastname: Chang
authors.forename: Hong
authors.initials: H
authors.lastname: Zhang
authors.forename: Hua
authors.initials: H
authors.lastname: Zhao
authors.forename: Xiao
authors.initials: X
authors.lastname: Bai
authors.forename: Fei
authors.initials: F
authors.lastname: Xie
authors.forename: Juan
authors.initials: J
authors.lastname: Sun
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D058186:Acute Kidney Injury / Q000175:diagnosis* / Q000601:surgery; D000209:Acute-Phase Proteins / Q000652:urine*; D000328:Adult; D000368:Aged; D019540:Area Under Curve; D015415:Biomarkers / Q000652:urine; D015331:Cohort Studies; D004797:Enzyme-Linked Immunosorbent Assay; D050556:Fatty Acid-Binding Proteins / Q000652:urine*; D005260:Female; D006801:Humans; D000071068:Lipocalin-2; D054834:Lipocalins / Q000652:urine*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011518:Proto-Oncogene Proteins / Q000652:urine*; D012372:ROC Curve
chemical_list: D000209:Acute-Phase Proteins; D015415:Biomarkers; C493319:FABP1 protein, human; D050556:Fatty Acid-Binding Proteins; C489506:LCN2 protein, human; D000071068:Lipocalin-2; D054834:Lipocalins; D011518:Proto-Oncogene Proteins