Evaluation of a single sampling method for estimation of plasma iohexol clearance in dogs and cats with various kidney functions

Abstract

Plasma iohexol clearance (PCio) is a practical method for measuring the glomerular filtration rate (GFR) in clinical settings. However, it is too time-consuming for routine application and requires hospitalization for at least half a day. Therefore, the development of a simpler procedure for plasma clearance is necessary to allow the frequent measurement of GFR in clinical settings. The purpose of the present study was to evaluate a single sampling method for estimation of PCio in dogs and cats with various kidney functions. The PCio determined by the 1-compartment model using 3 samples (PCio 3samples) was used as a reference for the evaluation of the single sampling method (PCio single). Plasma iohexol concentration was determined by a cerium arsenite colorimetric method. PCio single was calculated using the equation obtained by nonlinear regression analysis. PCio single was significantly correlated with PCio 3samples in both dogs and cats (dogs: R2=0.985, P2=0.986, Psingle may be very useful for the detection of decreasing GFR in dogs and cats.