Indirect markers of glomerular filtration rate in dogs and cats: a review

Abstract

Early diagnosis of kidney disease continues to be a subject of intense interest. Direct measurement of glomerular filtration rate is too complicated for first-line practices; thus, indirect markers of renal function have also been evaluated. Creatinine, traditionally measured as a readout of renal function, has limitations in its sensitivity. In dogs and cats, cystatin C became popular approximately 15 years ago, but recent reports question its usefulness, especially in cats. Symmetric dimethylarginine seems to be very promising as a marker of glomerular filtration rate with the ability to detect renal impairment earlier than creatinine. This article presents current knowledge of qualities, limitations, advantages and availability of novel and traditionally used biomarkers of glomerular filtration rate in dogs and cats.