eGFR (CKD-EPI)
What it measures, and what changes the number.
eGFR is an estimate of how much blood the kidneys filter each minute, adjusted to a standard body size. It is not measured directly but calculated with the CKD-EPI equation, using the blood creatinine result together with age and sex, and in some versions cystatin C.
It is read alongside creatinine, from which it is derived, and often with cystatin C, urea or BUN, and urine protein tests. Creatinine clearance from a timed urine collection is another way to assess filtration.
Because it depends on creatinine, anything that shifts creatinine shifts eGFR: muscle mass, a recent meat-heavy meal, creatine supplements, intense exercise and dehydration. Labs may use different versions of the CKD-EPI equation, which can give different results from the same sample. Labs may print it as EGFR, eGFR, Filtrado glomerular estimado (CKD-EPI), or eGFR (Estimated Glomerular Filtration Rate).
Often read alongside: Creatinine, Cystatin C, BUN (urea nitrogen), Urea, Creatinine clearance