Evaluation of the Effects of a Therapeutic Renal Diet to Control Proteinuria in Proteinuric Non‐Azotemic Dogs Treated with Benazepril

BACKGROUND: Angiotensin‐converting enzyme inhibitors (ACEIs) are currently used to control proteinuria in dogs with chronic kidney disease. Renal diets (RDs) have beneficial effects in the management of azotemic dogs, but its role in proteinuric non‐azotemic (PNAz) dogs has been poorly documented. HYPOTHESIS: Administration of a RD to PNAz dogs treated with benazepril (Be) improves proteinuria control compared with the administration of a maintenance diet (MD). ANIMALS: Twenty‐two PNAz (urine protein/creatinine ratio [UPC] >1) dogs. METHODS: Randomized open label clinical trial design. Dogs were assigned to group‐MD (5.5 g protein/100 kcal ME)/Be or to group‐RD (3.7 g protein/100 kcal ME)/Be group during 60 days. Dogs with serum albumin (Alb) <2 g/dL received aspirin (1 mg/kg/12 hours). A physical examination, systolic blood pressure (SBP) measurement, complete blood count (CBC), biochemistry panel, urinalysis, and UPC were performed at day 0 (D0) and day 60 (D60). RESULTS: At D0, there were no significant differences between groups in the evaluated variables. During the study, logUPC (geometric mean (95% CI) and SBP (mean±SD mmHg) significantly decreased (paired t‐test, P = 0.001) in Group‐RD (logUPC(D0) = 3.16[1.9–5.25]; UPC(D60) = 1.20 [0.59–2.45]; SBP(D0) = 160 ± 17.2; SBP(D60) = 151 ± 15.8), but not in Group‐MD (UPC(D0) = 3.63[2.69–4.9]; UPC(D60) = 2.14 [0.76–6.17]; SBP(D0) = 158 ± 14.7; SBP(D60) = 153 ± 11.5). However, RM‐ANOVA test did not confirm that changes were consequence of dietary modification. Weight and Alb concentration did not change significantly in any group. CONCLUSION AND CLINICAL RELEVANCE: The administration of a RD to PNAz dogs treated with Be might help to control proteinuria and SBP compared with the administration of a MD, without inducing clinically detectable malnutrition, but more studies are warranted.