Effect of enalapril on proteinuria after kidney transplantation.

We studied the effect of enalapril, an inhibitor of angiotensin-converting enzyme (iACE), on proteinuria and renal function in recipients of renal allografts. Twenty-two patients with post-transplant nephrotic syndrome were treated with incremental doses of enalapril for 1 year. Urinary protein excretion decreased after 2 months of treatment from a mean of 8.9 g/day (range 4.0-18.9 g/day) to 4.5 g/day (range 0.4-10.0 g/day; P < 0.01) and remained significantly low for the rest of the study. However, in the same period, creatinine clearance did not change significantly; it went from 47.8 ml/min (range 17.1-110.3 ml/min) before treatment to 44.2 ml/min (range 16.5-88.5 ml/min) after 2 months of iACE therapy. Analysis of individual data showed that there was a significant reduction in proteinuria in 14 of the 22 patients and that the rate of deterioration of renal function did not increase in 17 of the 22 patients. We did not observe any serious side effects of enalapril administration. The results of our study prove that iACE can be used safely and effectively to reduce post-transplant proteinuria.