REDUCED INCIDENCE OF HYPERURICEMIA, GOUT, AND RENAL FAILURE FOLLOWING LIVER TRANSPLANTATION IN COMPARISON TO HEART TRANSPLANTATION: A LONG-TERM FOLLOW-UP STUDY

Background. Hyperuricemia and gout are common complications of heart transplantation, reaching a prevalence of 84% and 30%, respectively, in heart transplant recipients. In contrast, they are seldom reported following orthotopic liver transplantation (OLT). Methods. We retrospectively evaluated 75 consecutive liver transplant recipients and 47 consecutive heart transplant recipients, followed for at least 3 years after transplantation in a single transplantation center in Jerusalem, Israel. Data was collected on demographic and clinical variables, levels of uric acid, the occurrence of gout, renal function, and variables effecting hyperuricemia, such as weight and medications. Results. Clinical gout was significantly more prevalent in heart recipients than in liver recipients (25.5% and 2.6%, respectively). Hyperuricemia was present in 100% of heart recipients, with an average uric acid level of 451 mol/l, as compared with 85.7% and 403 mol/l for liver recipients (P<0.001 for both variables). Univariate analysis identified several parameters which significantly influenced the difference in hyperuricemia and gout among the two groups including age, gender, rejection episodes, hypertension, diabetes mellitus, the level of uric acid prior to transplantation, and the use of cyclosporine A, diuretics, steroids, and aspirin. Use of tacrolimus and azathioprine were associated with decreased incidence of hyperuricemia and gout. Multivariate analysis identified the type of transplantation as the only independent risk factor predicting the development of hyperuricemia and gout. Conclusion. Clinical gout and hyperuricemia were significantly more prevalent in heart recipients than in liver recipients. The disparity can be explained by differences in age, gender and renal function among the groups, as well as by the use of different medication regimens. Hyperuricemia and gout are common complications of heart transplantation, reaching a prevalence of up to 84% and 30%, respectively, in heart transplant recipients (1– 4). In contrast, they are seldom reported following orthotopic liver transplantation (OLT) (5, 6). Recently, Neal et al. (5) reported a prevalence of hyperuricemia of 47% in 134 consecutive OLT recipients, with a 6% prevalence of clinical gout. The difference between the heart and liver transplantation groups has been attributed to different immunosuppression regimens, use of diuretics, and the presence of renal function impairment (7–12), but no direct comparison of hyperuricemia and gout between different solid organ transplantation patient groups has been previously executed. We retrospectively compared the prevalence of hyperuricemia and clinical gout in heart and liver organ recipients, and analyzed variables affecting uric acid metabolism and excretion, such as body weight, renal function and different medication regimens. Our results show that clinical gout and hyperuricemia are significantly less prevalent in liver recipients, a difference that can be attributed to clinical and laboratory differences between the groups, as well as to the use of different medical regimens following transplantation.