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 antihypertensive drugs used. Results: At the start of allopurinol therapy, mean serum uric acid level was greater in the allopurinol (476 +/- 119 mu mol/L) than control group (404 +/- 125 mu mol/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 mu mol/L) than control group (452 +/- 95 mu mol/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.