Use of Leflunomide in Renal Transplant Recipients with Ganciclovir-Resistant/Refractory Cytomegalovirus Infection: A Case Series from the University of Chicago

INTRODUCTION: Although antiviral prophylaxis for cytomegalovirus (CMV) is widely used, CMV infection remains common in renal transplant recipients with adverse consequences. METHODS: We report 5 cases of renal transplant recipients with resistant CMV infection who were successfully managed with leflunomide at the University of Chicago Medical Center. RESULTS: Five renal transplant recipients (2 simultaneous pancreas/kidney transplants, 3 deceased donor kidney transplants) were diagnosed with GCV-resistant CMV infection from 2003 to 2011. Of the 4 patients who had resistance genotype testing, 3 showed a UL97 mutation and 1 patient had a clinically resistant CMV infection. All patients received CMV prophylaxis with valganciclovir for 3 months. The number of days from the date of transplant to viremia ranged from 38 to 458 days (median 219). All 5 patients received other antiviral agents (e.g. ganciclovir, foscarnet), and in 4 patients, viremia was cleared before leflunomide was initiated as consolidation (or maintenance) therapy. CONCLUSION: Leflunomide was well tolerated and successful in preventing recurrence of viremia in renal transplant recipients with resistant CMV infection. The beneficial effect of leflunomide in this setting warrants further investigation.