title: Reference intervals for serum creatinine with enzymatic assay and evaluation of four equations to estimate glomerular filtration rate in a healthy Chinese adult population.
abstract: BACKGROUND
  With the wide usage of enzymatic assays to determine serum creatinine (Scr) in China, reference interval (RI) needs to be established. At the same time, the performance of Scr based equations to calculate estimated glomerular filtration rate (eGFR) in healthy Chinese adults has not been extensively investigated.
  
  
  METHODS
  This study has strictly followed the International Federation of Clinical Chemistry (IFCC) recommendations and the Clinical Laboratory Standards Institute (CLSI) C28-A2 document. A total number of 778 healthy Chinese adults (male 433, female 345) were enrolled in this study.
  
  
  RESULTS
  By nonparametric method, RIs for males were: <60 years, 58-93 μmol/l and >60 years, 54-109 μmol/l; RIs for females were: <60 years, 42-69 μmol/l and >60 years, 43-83 μmol/l. Modification of Diet in Renal Disease (MDRD) equation and MDRD for Japanese made the percentage of eGFR >90 ml/min/1.73 m(2) 31.7% and 4.9%; percentage of eGFR 60-89 ml/min/1.73 m(2) 65.2% and 64.0%, respectively. Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation and CKD-EPI for Asian made the percentage of eGFR >90 ml/min/1.73 m(2) 89.2% and 94.0%; percentage of eGFR 60-89 ml/min/1.73 m(2) 10.3% and 5.7%, respectively.
  
  
  CONCLUSIONS
  Scr RIs of healthy Chinese adults were found to be lower than those of Caucasians. Two MDRD equations underestimated GFR, while two CKD-EPI equations seemed to estimate a reasonable distribution of eGFR in healthy Chinese adult populations.
authors.affiliation: Department of Clinical Laboratory, Peking University First Hospital, Beijing, China.
authors.forename: XueJing
authors.initials: X
authors.lastname: Wang
authors.forename: GuoBin
authors.initials: G
authors.lastname: Xu
authors.forename: HaiXia
authors.initials: H
authors.lastname: Li
authors.forename: Yan
authors.initials: Y
authors.lastname: Liu
authors.forename: Fang
authors.initials: F
authors.lastname: Wang
mesh_terms: D000328:Adult; D000368:Aged; D002681:China; D003404:Creatinine / Q000097:blood* / Q000592:standards; D057075:Enzyme Assays; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D015203:Reproducibility of Results
chemical_list: D003404:Creatinine