The use of angiotensin-converting enzyme inhibitors in renal transplant patients

New insights in chronic allograft rejection

Chronic allograft nephropathy remains the main cause of renal graft failure. Immunologic mechanisms seem mostly responsible for the injury and subsequent fibrogenic tissue response while nonimmune mechanisms act mostly as progression factors. In this article, these factors are reviewed along with the changes that take place in the graft and new insights into possible therapeutic strategies.

Long-term outcomes of renal transplantation: a result of the original endowment of the donor kidney and the inflammatory response to both alloantigens and injury

Recent data suggest that long-term allograft survival might be affected by two factors. The first is the endowment of the allograft, which consists of two elements: the nephron mass and the ability of these nephrons to repair injuries sustained during the transplant process. The second factor is renal inflammation. Although inflammation is traditionally ascribed to alloreactivity, recent data have shown that there is also a renal inflammatory response to early injury after transplantation, to brain death in the donor, and as part of the maladaptive response to nephron loss. These two factors contribute to the detrimental effects of delayed graft function or acute rejection on the long-term survival seen in most studies, and the beneficial effects of anti-inflammatory agents on the maladaptive response to nephron loss.

ACE inhibitors and angiotensin II antagonists in renal transplantation: an analysis of safety and efficacy

Angiotensin-converting enzyme inhibitors (ACEi) are a class of antihypertensive agents that decrease mortality in congestive heart failure and have established efficacy in the treatment of hypertension and the slowing of established diabetic nephropathy and other proteinuria-associated glomerulonephritides. These drugs have not gained wide acceptance in the treatment of hypertension in renal transplant recipients (RTRs) because of a potential for decreased renal blood flow and glomerular filtration rate associated with a single kidney and concomitant cyclosporine use. Experimental animal models suggest that ACEi may be of benefit in slowing the progression of chronic renal allograft rejection. We undertook a retrospective chart analysis of all RTRs in our institution who had been treated with an ACEi or an angiotensin II (AT II) antagonist, with the objectives of determining the safety, efficacy, and side effect profile of these medications. The minimum follow-up period was 6 months. One hundred seventy-seven of 642 RTRs were prescribed an ACEi or AT II antagonist. Forty-seven patients discontinued therapy, with the most common causes of discontinuation being cough (8 patients) and hyperkalemia (6 patients). The mean arterial blood pressure at each follow-up period was lower than that at the time of initiation of ACEi or AT II antagonist therapy, with a decrease from 92 +/- 12 mm Hg to 86 +/- 9 mm Hg (P < 0.05) after 3 years of treatment. The serum creatinine concentrations did not change throughout the follow-up period. There was a nonsustained increase from the baseline serum potassium of 4.4 +/- 0.5 to 4.6 +/- 0.6 mEq/L at 3 months (P < 0.05), but no further increases in potassium beyond this time. The mean hemoglobin concentration for the cohort did not change, but 13 RTRs given an ACEi for posttransplantation erythrocytosis (PTE) had a decrease in hemoglobin from 17.1 +/- 1.0 g/dL at the start of ACEi therapy to 14.8 +/- 2.2 g/dL at 3 years (P < 0.05). ACEi and AT II antagonists were generally effective antihypertensives, and were safe and well-tolerated agents in this cohort of RTRs. ACEi were also effective in the treatment of PTE.