title: Detection of decreased glomerular filtration rate in intensive care units: serum cystatin C versus serum creatinine.
abstract: BACKGROUND
  Detecting impaired glomerular filtration rate (GFR) is important in intensive care units (ICU) in order to diagnose acute kidney injuries and adjust the dose of renally excreted drugs. Whether serum Cystatin C (SCysC) may better reflect glomerular filtration rate than serum creatinine (SCr) in the context of intensive care medicine is uncertain.
  
  
  METHODS
  We compared the performance of SCysC and SCr as biomarkers of GFR in 47 critically ill patients (median SOFA (Sepsis-related Organ Failure Assessment) score of 5) for whom GFR was measured by a reference method (urinary clearance of iohexol).
  
  
  RESULTS
  Mean Iohexol clearance averaged 96 ± 54 mL/min and was under 60 mL/min in 28% of patients. Mean SCr and SCysC concentrations were 0.70 ± 0.33 mg/dL and 1.26 ± 0.61 mg/L, respectively. Area under the ROC curve for a GFR threshold of 60 mL/min was 0.799 and 0.942 for SCr and SCysC, respectively (p = 0.014).
  
  
  CONCLUSIONS
  We conclude that ScysC significantly outperfoms SCr for the detection of an impaired GFR in critically ill patients.
  
  
  BACKGROUND
  ClinicalTrials.gov: B7072006347.
authors.affiliation: Department of Nephrology-Dialysis, University of Liège, CHU Sart Tilman, Liège 4000, Belgium. pierre_delanaye@yahoo.fr.
authors.forename: Pierre
authors.initials: P
authors.lastname: Delanaye
authors.forename: Etienne
authors.initials: E
authors.lastname: Cavalier
authors.forename: Jérôme
authors.initials: J
authors.lastname: Morel
authors.forename: Manolie
authors.initials: M
authors.lastname: Mehdi
authors.forename: Nicolas
authors.initials: N
authors.lastname: Maillard
authors.forename: Guillaume
authors.initials: G
authors.lastname: Claisse
authors.forename: Bernard
authors.initials: B
authors.lastname: Lambermont
authors.forename: Bernard E
authors.initials: BE
authors.lastname: Dubois
authors.forename: Pierre
authors.initials: P
authors.lastname: Damas
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Krzesinski
authors.forename: Alexandre
authors.initials: A
authors.lastname: Lautrette
authors.forename: Christophe
authors.initials: C
authors.lastname: Mariat
mesh_terms: D058186:Acute Kidney Injury / Q000097:blood* / Q000175:diagnosis*; D015415:Biomarkers / Q000097:blood*; D003404:Creatinine / Q000097:blood*; D003422:Critical Care; D055316:Cystatin C / Q000097:blood*; D005260:Female; D005602:France; D005919:Glomerular Filtration Rate; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D015415:Biomarkers; D055316:Cystatin C; D003404:Creatinine