Diagnostic performance of serum cystatin c and serum creatinine in the prediction of chronic kidney disease in renal transplant recipients

Background Chronic kidney disease (CKD) has adverse impacts on mortality and morbidity of renal transplant recipients. Serum cystatin C (sCysC) is a novel marker in predicting the CKD. We therefore compare sCysC and serum creatinine (sCr) with the aim of improving the detection of CKD in renal transplant recipients. Methods We enrolled 106 renal transplant recipients and estimated glomerular filtration rates (GFR) using the Cockcroft-Gault (GFR CG) and the abbreviated Modification of Diet in Renal Disease (GFR aMDRD) formulae. We defined CKD as the presence of structural or functional kidney damage, irrespective of the diagnosis. Comparisons of sCysC and sCr in detecting CKD were analyzed. Results sCysC correlates with sCr significantly (r = 0.87; P < .001). The receiver operating characteristic curve demonstrates that sCysC has a better specificity and area under the curve, but less sensitivity than sCr in predicting CKD in renal transplant recipients if GFR is estimated by GFR CG. Additionally, if GFR was estimated by GFR aMDRD, the role of sCysC or sCr in prediction of CKD was comparable. Conclusion sCysC may be better than sCr to detect CKD in renal transplant recipients using the GFR CG.