Equazioni per la stima della velocità di filtrazione glomerulare: lontani da un punto di arrivo
Equations for estimating glomerular filtration rate: far from an end point

AUTORI

ABSTRACT

Equations for estimating glomerular filtration rate: far from an end point

The recent position paper by the European Federation of Laboratory Medicine (EFLM) advises against following
the US recommendations on the use of the new race-free version of the Chronic Kidney Disease-Epidemiology
Consortium (CKD-EPI 2021) equation to estimate the glomerular filtration rate (eGFR). The main concern derives
from a possible poor CKD estimation, causing an underestimation of renal impairment for the Caucasian population,
and therefore for all Europeans. Considering the relevance of the EFLM indication, Biochimica Clinica published the
Italian translation of the document and an accompanying editorial suggesting that the European position could be an
end point for a better eGFR harmonization.
However, the use of different equations for eGFR in US and Europe will entail rather a worse harmonisation: the eGFR
values are used for patients enrolment in numerous clinical studies, for the admission to diagnostic procedures or
therapies and for the evaluation of their complications and adverse effects. As a consequence, many clinical trials will
not be comparable, guidelines and recommendations will be less easily transferable from one country to another and
the “regionality” of the equations will not slow down the search for new equations, for different groups and different
countries. With equally shared responsibility between US and Europe, this situation seems to be a paradigmatic
example of how recommendations in laboratory medicine should not be developed.
Nevertheless, the EFLM indication not to adopt the CKD-EPI 2021 race-free equation should be accepted for the
moment in Europe, since the harmonization between neighbouring and regional sanitary structures is a priority in the
patient care. It should be strengthened that the problem has not been solved yet, and that a greater harmonization
action must be rapidly sought, with the aim of a homogeneous calculation and reporting of this widely diffused estimate

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