Treatment with low-dose angiotensin-converting enzyme inhibitor (ACEI) plus angiotensin II receptor blocker (ARB) in pediatric patients with IgA nephropathy

Abstract

IgA nephropathy associated with heavy proteinuria is considered a more progressive form of this disease. In this report, we describe the favorable clinical effect of combination therapy with low doses of an angiotensin-converting enzyme inhibitor (ACEI) and angiotensin II receptor blocker (ARB) in the chronic stage of pediatric IgA nephropathy associated with heavy proteinuria. We initially used ACEI for seven children with IgA nephropathy and heavy proteinuria who did not achieve remission with the routine treatment including steroids. With ACEI therapy alone, only three patients showed an antiproteinuric response. In one of the three patients, the proteinuria decreased by half, but was still over 1 g/day. In the other four patients, the proteinuria did not decrease. In these five patients, of whom one partial was a responder and four were non-responders for ACEI, ARB was added, and in marked contrast to ACEI therapy alone, the antiproteinuric effect was significantly augmented (p < 0.01). The antiproteinuric response induced by combination therapy was not accompanied by blood pressure changes. Urinary low-molecular protein and N-acetyl-beta-D-glucosaminidase (NAG) levels tended to decrease after both ACEI alone and combination therapy. These data indicate that inhibition therapy of the angiotensin system not only decreases proteinuria levels but also protects renal tubular cells. Moreover, there were no obvious side effects associated with this therapy during the follow-up period of our clinical trial. In conclusion, this report shows that the combination of low doses of ACEI and ARB might provide marked antiproteinuric and long-term renoprotective effects in pediatric IgA nephropathy, with this approach appearing to be both well-tolerated and safe.