Journal Article

Creatinine-based GFR predicting equations in renal transplantation: reassessing the tubular secretion effect

Nicolas Maillard, Manolie Mehdi, Lise Thibaudin, François Berthoux, Eric Alamartine and Christophe Mariat

in Nephrology Dialysis Transplantation

Published on behalf of European Renal Association - European Dialysis and Transplant Assoc

Volume 25, issue 9, pages 3076-3082
Published in print September 2010 | ISSN: 0931-0509
Published online March 2010 | e-ISSN: 1460-2385 | DOI: http://dx.doi.org/10.1093/ndt/gfq123
Creatinine-based GFR predicting equations in renal transplantation: reassessing the tubular secretion effect

Show Summary Details

Preview

Background. The real utility of blocking the tubular secretion of creatinine with cimetidine in order to ameliorate the prediction of renal graft function is questionable, particularly in the context of an increasing diffusion of the Modification of Diet in Renal Disease (MDRD) study equation. We have compared the impact of cimetidine on the performances of the Cockcroft–Gault (C–G) and MDRD equations in 56 renal transplant patients with an estimated glomerular filter rate (GFR) >30 mL/min/1.73 m2 for whom true GFR was directly measured by inulin clearance.

Methods. Serum creatinine concentration (SCr) was measured [isotope dilution mass spectrometry (IDMS) traceable enzymatic assay] at the beginning of the inulin clearance procedure and 2 days later, after three oral cimetidine doses of 800 mg every 12 h. Predictive and diagnostic performances of the re-expressed MDRD and C–G formulas were compared before and after cimetidine intake.

Results. Mean SCr (±SD) increased from 120 μmol/L (±34) before to 154 μmol/L (±47) after cimetidine. The beneficial effect of cimetidine was significant only on the accuracy of the C–G formula (accuracy 30% post-cimetidine of 93 and 79% for the C–G and MDRD equations, respectively). Likewise, while a higher proportion of patients were correctly staged using the chronic kidney disease classification after cimetidine with the C–G equation (59% before and 68% after), no improvement was seen with the MDRD formula (59 vs 57%). For both equations, receiver operating characteristic curves analysis showed only a marginal gain in GFR prediction.

Conclusion. Our data do not support the use of a cimetidine-based strategy for the evaluation of renal graft function in the clinic, particularly when the GFR is estimated by the MDRD equation.

Keywords: GFR predicting equations; kidney transplantation; renal function

Journal Article.  4008 words.  Illustrated.

Subjects: Nephrology

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.