Molecular Dx Significance 4/10

CKD-EPI 2009 outperforms MDRD-IDMS for eGFR estimation in heterogeneous hospital cohorts

Investigators compared four estimated glomerular filtration rate equations, including the legacy MDRD-IDMS, CKD-EPI 2009, CKD-EPI 2021, and the European Kidney Function Consortium model, in a retrospective cohort of 1,438 patients. The analysis revealed that MDRD-IDMS lacks consistency at eGFR values above 80 mL/min/1.73 m2, while CKD-EPI 2021 yields systematically higher results and EKFC reclassifies approximately 12% of patients into more advanced chronic kidney disease stages. CKD-EPI 2009 demonstrated the strongest agreement with current staging and the most balanced impact on patient classification. The study recommends CKD-EPI 2009 as the most suitable alternative for laboratory implementation, offering clinical chemists a validated pathway to modernize renal function reporting without disrupting established care pathways.

The original study

Retrospective and comparative assessment of MDRD, CKD-EPI, and EKFC equations for estimating glomerular filtration rate in a clinically heterogeneous hospital population.

Authors
Baldetti M, Belardi R, Velocci S, Luffarelli R, Di Carlo S, Bernardini S, et al.
Journal
International urology and nephrology
Type
Journal Article
PMID
42496793
Read the original study →

Original abstract

BACKGROUND: Chronic kidney disease (CKD) is projected to become the fifth leading cause of death by 2040. Accurate estimation of glomerular filtration rate (eGFR) is essential for diagnosis, staging, and management. Our laboratory still uses Modification of Diet in Renal Disease (MDRD) traceable to the Isotope Dilution Mass Spectrometry (IDMS) equation, which is now considered outdated due to reduced accuracy at higher eGFR values. More recent equations may offer improved performance. This study aimed to compare these four eGFR equations from both analytical and clinical perspectives to support the change of equation used in our laboratory. METHODS: Retrospectively, this study compared the routinely used MDRD equation with alternative eGFR formulas in order to evaluate the impact of adopting newer equations. RESULTS: The study population included 1438 patients (886 males and 552 females; mean ages of 60 and 63 years for males and females, respectively). MDRD-IDMS showed limited consistency above 80 mL/min/1.73 m2. Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) 2009 had the strongest agreement and similar staging, while CKD-EPI 2021 generated higher eGFR values. European Kidney Function Consortium (EKFC) reclassified about 12% of patients into more advanced stages, possibly influencing clinical management. CONCLUSIONS: Both CKD-EPI 2009 and EKFC proved to be suitable alternatives to MDRD-IDMS. However, CKD-EPI 2009 was identified as the most potentially appropriate equation for implementation in our hospital setting due to the characteristics of the served population and its balanced impact on CKD stage reclassification.