Creatinine clearance
What it measures, and what changes the number.
Creatinine clearance estimates how much blood the kidneys clear of creatinine over a given time. It combines the creatinine level in a blood sample with the amount of creatinine collected in urine over a timed period, usually a full day. Spanish language reports may list it as 'Aclaramiento de creatinina'.
It is read alongside blood creatinine, the urine volume from the same collection, and eGFR, which estimates filtration from a single blood sample without urine collection.
Accuracy depends heavily on collecting every drop of urine over the whole period; a missed void or an incorrectly timed collection changes the result. Body size is often factored in when the value is reported, and diet and exercise around the collection can also influence it.
Often read alongside: Creatinine, Urine volume (24h), eGFR (CKD-EPI), Urea