2015 ACVIM Forum Research Abstract Program

The records from 2 first opinion practices were searched for cats >9 years of age with and without renal azotemia. Renal azotemia was defined as a plasma creatinine concentration >2.0 mg/ dL with a concurrent urine specific gravity (USG) <1.035, or demonstration of azotemia on 2 consecutive occasions (at least 14 days apart) without evidence of a pre-renal cause. Cats were excluded if concurrent hyperthyroidism or other significant systemic disease were suspected. Active TGF-b1 concentrations were measured in feline urine using an active TGF-b1 ELISA developed for use with human samples, validated by intra-and interassay variability, assessment of dilutional parallelism and spike and recovery of exogenous TGF-b1. For the purposes of the cross-sectional study, cases were classified based upon baseline status and subsequent renal function, resulting in three groups: cats with renal azotemia (Group 1), non-azotemic cats which remained non-azotemic for 24 months (Group 2) and non-azotemic cats which developed azotemia within 24 months (Group 3). Comparisons between groups were made using the Kruskal-Wallis test. For the purposes of the longitudinal study cases with three consecutive urine samples leading up to a deterioration of renal function were classified into two groups: non-azotemic cats which developed azotemia after~12 months and azotemic cats with progression of CKD after~12 months. Progression was defined as a repeatable >25% increase in plasma creatinine from baseline. Comparisons between visits within these two groups were made using the Friedman test with post-hoc Wilcoxon sign rank tests where appropriate. Results are reported as median [range] or mean (AE S.D) as appropriate.