title: Cystatin C-based formula is superior to MDRD, Cockcroft-Gault and Nankivell formulae in estimating the glomerular filtration rate in renal allografts.
abstract: OBJECTIVE
  There are conflicting reports on the reliability of the various glomerular filtration rate formula in renal allografts, to assess the performance of various glomerular filtration rate formula in estimating renal function of renal allografts.
  
  
  METHODS
  Glomerular filtration rate was measured using an isotope Tc99m DTPA in 97 renal transplant patients and estimated using modification of diet in renal disease, Cockroft-Gault formula, Nankivell, and a cystatin C-based formula. The overall performance of these formula was evaluated by calculating bias, accuracy and precision.
  
  
  RESULTS
  Mean age was 39.8 years (-/+ 12.7), body mass index was 26.9 (-/+ 6.3) and serum creatinine was 114.5 micromol/L (-/+ 39.3). The mean measured glomerular filtration rate was 58.1 mL/min (-/+ 25.6). The bias with modification of diet in renal disease was 7.7 (P = .03), with Cockroft-Gault formula it was 3.2 (P = .3), with Nankivell it was 10.3 (P = .0002), and with cystatin C it was 0.31 (P = .9) The precisions (r) for modification of diet in renal disease, Cockroft-Gault formula, Nankivell, and cystatin C were 0.26 (P = .01), 0.26 (P = .01), 0.42 (P = .0001), and 0.60 (P < .0001), respectively. We also investigated the impact of sex, age, body mass index, and glomerular filtration rate on the performance of these 4 formula.
  
  
  CONCLUSIONS
  The best correlation, highest precision, accuracy, and least bias were seen when using cystatin C. The largest bias was seen when using Nankivell and modification of diet in renal disease formula.
authors.affiliation: King Saud Bin Abdulaziz University for Health Sciences, Kingdom of Saudi Arabia.
authors.forename: Ammar
authors.initials: A
authors.lastname: Qutb
authors.forename: Ghulam
authors.initials: G
authors.lastname: Syed
authors.forename: Hani M
authors.initials: HM
authors.lastname: Tamim
authors.forename: Mohammad
authors.initials: M
authors.lastname: Al Jondeby
authors.forename: Maha
authors.initials: M
authors.lastname: Jaradat
authors.forename: Waleed
authors.initials: W
authors.lastname: Tamimi
authors.forename: Ghormullah
authors.initials: G
authors.lastname: Al Ghamdi
authors.forename: Salem
authors.initials: S
authors.lastname: Al Qurashi
authors.forename: Ahmed
authors.initials: A
authors.lastname: Flaiw
authors.forename: Fayez
authors.initials: F
authors.lastname: Hejaili
authors.forename: Abdulla A
authors.initials: AA
authors.lastname: Al Sayyari
mesh_terms: D000328:Adult; D015982:Bias; D015415:Biomarkers / Q000097:blood; D003404:Creatinine / Q000097:blood; D055316:Cystatin C / Q000097:blood*; D005260:Female; D005919:Glomerular Filtration Rate; D006305:Health Status Indicators; D006801:Humans; D007674:Kidney Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology; D016030:Kidney Transplantation / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D011237:Predictive Value of Tests; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D016284:Technetium Tc 99m Pentetate; D014184:Transplantation, Homologous; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; C525030:CST3 protein, human; D055316:Cystatin C; D019275:Radiopharmaceuticals; D003404:Creatinine; D016284:Technetium Tc 99m Pentetate