Effect of allopurinol on slowing allograft functional decline in kidney transplant recipients.

OBJECTIVES Hyperuricemia may be a risk factor for graft loss in kidney transplant recipients. The purpose of this study was to evaluate the effects of allopurinol in kidney transplant recipients. MATERIALS AND METHODS A single center retrospective case-control study was performed with kidney transplant recipients who were treated with allopurinol (54 patients) and a control group matched for time of transplant (± 3 months) and estimated glomerular filtration rate (54 patients). We evaluated the relation between allopurinol use and estimated glomerular filtration rate, graft survival, blood pressure, and number of anti-hypertensive drugs used. RESULTS At the start of allopurinol therapy, mean serum uric acid level was greater in the allopurinol (476 ± 119 μmol/L) than control group (404 ± 125 μmol/L; P ≤ .001) and estimated glomerular filtration rate was similar between the 2 groups (allopurinol, 39 ± 16 mL/min; control, 38 ± 16 mL/min; not significant). At 1 year, mean estimated glomerular filtration rate was greater in the allopurinol than control group (allopurinol, 41 ± 15 mL/min; control, 36 ± 13 mL/min; P ≤ .04). At 2 years, mean serum uric acid level was significantly lower in the allopurinol (399 ± 101 μmol/L) than control group (452 ± 95 μmol/L; P ≤ .02). Graft survival, blood pressure, and antihypertensive requirements were similar between the groups. CONCLUSIONS Allopurinol use is associated with preservation of estimated glomerular filtration rate in kidney transplant recipients. There may be potential benefit in treating asymptomatic hyperuricemia in kidney transplant recipients.