Effects of Enalapril versus Placebo as a Treatment for Canine Idiopathic Glomerulonephritis

A blinded, multicenter, prospective clinical trial assessed the effects of enalapril (EN) versus standard care in dogs with naturally occurring, idiopathic glomerulonephritis (GN). Twenty-nine adult dogs with membranous (n = 16) and membranoproliferative (n = 13) GN were studied. Dogs were randomly assigned to receive either EN (0.5 mg/kg PO q12–24h; n = 16) or placebo (n = 14) for 6 months (1 dog was treated first with the placebo and then with EN). All dogs were treated with low-dose aspirin (0.5–5 mg/kg PO q12–24h) and fed a commercial diet. At baseline, serum creatinine (SrCr), systolic blood pressure (SBP), and glomerular histologic grade were not different between groups, but the urine protein/creatinine ratio (UP/C) was greater in the EN group compared with the placebo group (8.7 ± 4.4 versus 4.7 ± 2.3). After 6 months of treatment, the change in UP/C from baseline was significantly different between groups (EN =—4.2 ± 1.4 versus 1.9 ± 0.9 in the placebo group). When data were adjusted for changes in SrCr (SrCr X UP/C) a similar significant reduction was noted (—2.2 ± 15.2 versus 8.4 ± 10.1). The change in SBP after 6 months of treatment also was significantly different between groups (EN =—12.8 ± 27.3 versus 5.9 ± 21.5 mm Hg in the placebo group). Response to treatment was categorized as improvement (assigned a value of 2), no progression (assigned a value of 1), and progression (assigned a value of 0). Response was significantly better in the EN group (1.4 ± 0.8) compared with the placebo group (0.3 ± 0.5). These results suggest that EN treatment is beneficial in dogs with naturally occurring idiopathic GN.