Evaluation of iohexol as a marker for the clinical measurement of glomerular filtration rate in dogs.

The contrast medium iohexol can be used as a marker for the measurement of glomerular filtration rate. It has the advantages of sample stability and the availability of a simple, automated (though expensive) analyser. The clearance of iohexol was compared with the clearance of Tc-DTPA in 24 dogs with known or suspected renal impairment. The results were comparable but fractionally lower with iohexol. The correction factors developed for human beings were found to be satisfactory in the dogs, thus validating the software routines used in the automated analyser with the canine samples.