title: Early detection of acute kidney injury by serum cystatin C in critically ill children.
abstract: BACKGROUND
  We prospectively evaluated whether serum cystatin C (CysC) detected acute kidney injury (AKI) earlier than basal serum creatinine (Cr).
  
  
  METHODS
  In 107 pediatric patients at high risk of developing AKI, serum Cr and serum CysC were measured upon admission. Baseline estimated creatinine clearance (eCCl) was calculated using a CysC-based glomerular filtration rate (GFR) equation from a serum Cr measured at the pediatric intensive care unit (PICU) entrance.
  
  
  RESULTS
  The median age was 10 months (interquartile range, 3-36 months). Serum Cr, serum CysC, and eCCl (mean ± standard deviation [range]) were 0.5 ± 0.18 mg/dl (0.2-1.1 mg/dl), 0.53 ± 0.78 (0.01-3.7 mg/l), and 72.55 ± 28.72 (20.6-176.2) ml/min per 1.73 m(2), respectively. The serum CysC level in patients with AKI was significantly higher than children with normal renal function (p < 0.001). The values for the cut-off point, sensitivity, specificity, and the area under curve (AUC) were determined for CysC as 0.6 mg/l, 73.9 %, 78.9 %, and 0.92 [95 % confidence interval (0.82-1)], respectively, and for Cr the values were 0.4 mg/dl, 68 %, 46.2 %, and 0.39, [95 % confidence interval (0.24-0.54)], respectively. The receiver operating characteristics (ROC) curve analysis revealed that CysC had a significantly higher diagnostic accuracy than eCCl (p < 0.001).
  
  
  CONCLUSIONS
  Our results identify that the sensitivity of serum CysC for detecting AKI is higher than that of serum Cr in a heterogeneous pediatric intensive care unit (PICU) population.
authors.affiliation: Department of Pediatric Nephrology, Children's Hospital Medical Center, Tehran University of Medical Sciences, Dr. Gharib St. Azadi Avenue, 14197, Tehran, Iran.
authors.forename: Neamatollah
authors.initials: N
authors.lastname: Ataei
authors.forename: Behnaz
authors.initials: B
authors.lastname: Bazargani
authors.forename: Sonbol
authors.initials: S
authors.lastname: Ameli
authors.forename: Abbas
authors.initials: A
authors.lastname: Madani
authors.forename: Faezeh
authors.initials: F
authors.lastname: Javadilarijani
authors.forename: Mastaneh
authors.initials: M
authors.lastname: Moghtaderi
authors.forename: Arash
authors.initials: A
authors.lastname: Abbasi
authors.forename: Sedigheh
authors.initials: S
authors.lastname: Shams
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Ataei
mesh_terms: D058186:Acute Kidney Injury / Q000097:blood* / Q000175:diagnosis*; D019540:Area Under Curve; D015415:Biomarkers / Q000097:blood*; D002675:Child, Preschool; D003401:Creatine / Q000097:blood; D016638:Critical Illness; D055316:Cystatin C / Q000097:blood*; D042241:Early Diagnosis; D006801:Humans; D007223:Infant; D012372:ROC Curve
chemical_list: D015415:Biomarkers; D055316:Cystatin C; D003401:Creatine