CURRENT STANDARDS OF KIDNEY FUNCTION ASSESSMENT: IMPLEMENTATION OF KDIGO AND EFLM GUIDELINES IN LABORATORY PRACTICE
DOI:
https://doi.org/10.11603/mcch.2410-681X.2026.i3.16533Keywords:
chronic kidney disease (CKD); glomerular filtration rate (GFR); creatinine; cystatin C; albumin-to-creatinine ratio (ACR); CKD-EPI EKFC, KFREAbstract
Introduction. Chronic kidney disease (CKD) holds a leading position in the structure of global mortality, which drives the need for prevention and standardization of early disease diagnosis. Although laboratory testing is a key tool for evaluating renal function, a critical heterogeneity in methods, calculation equations, and units of measurement is still observed in European laboratory practice. The aim of the study – to substantiate the necessity of utilizing a unified laboratory-diagnostic approach for the early diagnosis of CKD based on international KDIGO and EFLM guidelines, as well as current scientific literature data. Research Methods. A detailed analysis and systematization of approaches regarding the use of novel biomarkers and CKD assessment tools were performed in accordance with international guidelines (KDIGO 2024), the developments of the EFLM European Kidney Function Consortium / CKD committee, and relevant sources from PubMed and Scopus scientometric databases. The search was conducted using the following keywords: chronic kidney disease (CKD), estimated glomerular filtration rate (eGFR), creatinine, cystatin C, albuminuria, CKD-EPI, EKFC, KFRE. Results and Discussion. Preanalytical and analytical limitations of the Jaffe method for creatinine determination were analyzed, and the advantage of enzymatic assays was demonstrated. It was determined that the implementation of the CKD-EPI 2021 equation in Europe leads to a systematic artificial underestimation of the estimated glomerular filtration rate (eGFR) and an artifactual 25 % increase in CKD prevalence. The introduction of the population-specific EKFC equation for children from 2 years of age and adults, which is based on the age- and sex-specific index Q, was substantiated. Rules for calculating GFR using the combined formula (creatinine/cystatin C) were defined, alongside the standardization of kidney filter damage assessment via the urinary albumin-to-creatinine ratio (ACR) in a random morning urine sample, with a substantiated rejection of the obsolete term “microalbuminuria”. The role of the predictive KFRE equation for assessing the risk of kidney failure was outlined. Conclusions. Early detection of CKD depends on the correct implementation of novel biomarkers, methods for estimating glomerular filtration rate, and the harmonization of laboratory reporting metrics. Prioritizing enzymatic methods for creatinine determination, implementing cystatin C and ACR indicators into daily practice, and utilizing relevant equations for eGFR assessment will allow for the unification of the diagnostic process and optimize the risk assessment of kidney failure in patients.
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