What are the current recommendations regarding use of angiotensin-converting enzyme (ACE) inhibitors for hypertension after renal transplantation?
ACE inhibitors are generally safe, effective, and well-tolerated in transplant recipients with hypertension. The prevalence of hypertension in this population is high (60% to 85%) and results from the use of immunosuppressive drugs, chronic allograft nephropathy (CAN) with raised creatinine and proteinuria, recurrence of primary disease, renal artery stenosis, and the presence of dysfunctional native kidneys. The National Kidney Foundation Task Force on cardiovascular disease recommends that blood pressure should be 130/85 mm Hg for renal transplant recipients without proteinuria and 125/75 mm Hg for patients with proteinuria. ACE inhibitors are commonly used in such settings and especially so when proteinuria is present. These agents may also stabilize the decline in renal function seen in CAN by inhibiting TGF-beta. Although ACE inhibitors may worsen anemia, this may have a beneficial effect in patients with erythrocytosis. Hyperkalemia may also occasionally be a problem, and when using these agents, monitoring of potassium and serial hemoglobin levels is recommended. The addition of a thiazide or loop diuretic circumvents this problem. By lowering the intraglomerular pressure, ACE inhibitors may result in an increase in serum creatinine. This is usually a transient and reversible effect. As ACE inhibitors are relatively contraindicated in the presence of renal artery stenosis, this condition should be excluded by duplex Doppler prior to prescribing the drug. By improving alterations of the cardiovascular system, ACE inhibitors could reduce cardiovascular morbidity and mortality in kidney transplant recipients. Despite these added effects, some authors suggest that ACE inhibitors be reserved only for patients with erythrocytosis or heavy proteinuria.