title: Monitoring of plasma creatinine and urinary γ-glutamyl transpeptidase improves detection of acute kidney injury by more than 20%.
abstract: OBJECTIVE
  We sought to determine how early we can detect acute kidney injury inpatients at intensive care unit admission by combining the use of plasma creatinine and urinary γ-glutamyl transpeptidase.
  
  
  METHODS
  Prospective study including development (n = 100) and validation (n = 56) cohorts.
  
  
  METHODS
  Intensive care unit of a university hospital.
  
  
  METHODS
  None.
  
  
  RESULTS
  To determine acute kidney injury, we subtracted measured creatinine clearance from theoretical creatinine clearance with a 25% reduction signifying acute kidney injury. Its incidence in 100 consecutive patients was 36%. An indexed urinary γ-glutamyl transpeptidase-to-urinary creatinine ratio was significantly increased in the patients with acute kidney injury and did not correlate with plasma creatinine (p = .3). Using a predefined threshold of indexed urinary γ-glutamyl transpeptidase-to-urinary creatinine ratio (>12.4 units/mmol) and plasma creatinine (>89 μmol/L), acute kidney injury detection was significantly improved, making it possible to detect 22 (22%) additional patients with acute kidney injury. This finding was confirmed in the validation group. The rates of false-positive results were 30% and 19% in the data development and internal validation cohorts, respectively.
  
  
  CONCLUSIONS
  The use of low-cost, widely available markers (creatinine and urinary γ-glutamyl transpeptidase) increases the detection of acute kidney injury. Further studies are needed to determine the impact on outcome with the use of these biomarkers.
authors.affiliation: Service d'anesthésie et de réanimation, Hôpital Nord, Assistance Publique-Hôpitaux de Marseille, Université de la Méditerranée, Marseille, France.
authors.forename: Valéry
authors.initials: V
authors.lastname: Blasco
authors.forename: Sandrine
authors.initials: S
authors.lastname: Wiramus
authors.forename: Julien
authors.initials: J
authors.lastname: Textoris
authors.forename: François
authors.initials: F
authors.lastname: Antonini
authors.forename: Carole
authors.initials: C
authors.lastname: Bechis
authors.forename: Jacques
authors.initials: J
authors.lastname: Albanèse
authors.forename: Claude
authors.initials: C
authors.lastname: Martin
authors.forename: Marc
authors.initials: M
authors.lastname: Leone
mesh_terms: D058186:Acute Kidney Injury / Q000175:diagnosis* / Q000453:epidemiology*; D000328:Adult; D015415:Biomarkers / Q000032:analysis; D015331:Cohort Studies; D003404:Creatinine / Q000097:blood*; D016638:Critical Illness / Q000628:therapy; D042241:Early Diagnosis; D005260:Female; D005500:Follow-Up Studies; D006785:Hospitals, University; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric; D005723:gamma-Glutamyltransferase / Q000652:urine*
chemical_list: D015415:Biomarkers; D003404:Creatinine; D005723:gamma-Glutamyltransferase