Evaluation of Kidney Function in Cats

March 19, 2009

Heiene, R., B. S. Reynolds, et al. (2009). “Estimation of glomerular filtration rate via 2- and 4-sample plasma clearance of iohexol and creatinine in clinically normal cats.” American Journal of Veterinary Research 70(2): 176-185.

Large numbers of elderly cats develop renal disease. Survival time after diagnosis is variable. The ability to estimate glomerular filtration rate (GFR) could lead to early detection of renal disease and allow earlier institution of therapeutic measures that protect renal function. GFR is considered the overall best indicator of renal function in healthy and diseased animals and is estimated by measurement of clearance of a marker substance. This study used 51 cats to compare 2 methods for estimating GFR, evaluate the effect of ages and body size and their interaction on GFR estimates, and establish reference ranges for GFR in clinically normal cats. The two contrast markers evaluated were iohexol and creatinine. No adverse drug reactions were noted with the use of iohexol for GFR estimation. GFR values were established in all the cats in the study. A difference in estimated GFR between young and old cats was not evident in this study. The study did find a small but significant effect of body size on estimated GFR and this was more important than the effect of age. The 4-sample method was a convenient and reliable means to establish GFR in cats with values considered normal or near normal. The 2-sample method also provided acceptable approximations for GFR and worked well in non-sedated cats. However, the 4-sample method is more accurate in cats with low renal function. Since body weight should be taken into account for estimating GFR, further studies are indicated to provide more information. [VT]
>> PubMed Abstract

Related articles:
van Hoek, I., H. P. Lefebvre, et al. (2008). “Plasma clearance of exogenous creatinine, exo-iohexol, and endo-iohexol in hyperthyroid cats before and after treatment with radioiodine.” J Vet Intern Med 22(4): 879-885.
>> PubMed Abstract

van Hoek, I., E. Vandermeulen, et al. (2007). “Comparison and reproducibility of plasma clearance of exogenous creatinine, exo-iohexol, endo-iohexol, and 51Cr-EDTA in young adult and aged healthy cats.” J Vet Intern Med 21(5): 950-8.
>> PubMed Abstract