title: Suitability of the IDMS-traceable MDRD equation method to estimate GFR in early postoperative renal transplant recipients.
abstract: OBJECTIVE
  Accurate measurement of glomerular filtration rate (GFR) is critical for the management of kidney transplant recipients. Comparison of creatinine and cystatin C in renal transplant recipients gave conflicting results. We aimed to compare the performance of creatinine- and cystatin C-based equations and creatinine clearance in 102 early postoperative Korean renal transplant patients.
  
  
  METHODS
  We measured (51)Cr-EDTA clearance using a 2-compartment model and considered this the reference GFR. Then, we estimated GFR using 13 creatinine- and 7 cystatin C-based equations. Serum creatinine value was calibrated to isotope-dilution mass spectrometry (IDMS).
  
  
  RESULTS
  The mean reference GFR was 76.77 +/- 17.01 ml/min/1.73 m(2). The IDMS-traceable MDRD (IDMS-MDRD) equation had the highest accuracy (94.12 within 30% of the reference; 99.02 within 50% of the reference) with a bias of 0.33 ml/min/1.73 m(2) and a precision of 12.57 ml/min/1.73 m(2). The Mayo Clinic equation also performed well (92.16% within 30% of the reference; 99.02% within 50% of the reference; bias: -0.19 ml/min/1.73 m(2)). As for cystatin C-based equations, the Filler equation had the least bias (0.03 ml/min/1.73 m(2)) but low accuracy (78.43% within 30% of the reference).
  
  
  CONCLUSIONS
  We conclude that the IDMS-MDRD equation provided the best estimate of GFR in our early postoperative Korean renal transplant patients.
authors.affiliation: Division of Nephrology, Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
authors.forename: Youngsun
authors.initials: Y
authors.lastname: Yeo
authors.forename: Duck-Jong
authors.initials: DJ
authors.lastname: Han
authors.forename: Dae Hyuk
authors.initials: DH
authors.lastname: Moon
authors.forename: Jung Sik
authors.initials: JS
authors.lastname: Park
authors.forename: Won Seok
authors.initials: WS
authors.lastname: Yang
authors.forename: Jai Won
authors.initials: JW
authors.lastname: Chang
authors.forename: Seung Woon
authors.initials: SW
authors.lastname: Byun
authors.forename: Su-Kil
authors.initials: SK
authors.lastname: Park
mesh_terms: D000293:Adolescent; D000328:Adult; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D016030:Kidney Transplantation / Q000706:statistics & numerical data*; D007723:Korea / Q000453:epidemiology; D008297:Male; D017063:Outcome Assessment, Health Care / Q000379:methods; D011182:Postoperative Care / Q000379:methods / Q000706:statistics & numerical data; D015995:Prevalence; D051437:Renal Insufficiency / Q000175:diagnosis* / Q000453:epidemiology / Q000601:surgery*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016896:Treatment Outcome; D055815:Young Adult