Clinical outcomes of tuberculosis in renal transplant recipients

Tuberculosis (TB) is an important cause of morbidity and mortality in renal transplant recipients. Rifampin has a potent sterilizing activity, but it reduces the serum concentrations of the immunosuppressive agents. Moreover, the possible contribution made by mycobacterial infection to the incidence of graft rejection or renal dysfunction remains unclear. In this study, we investigated the recurrence of TB and graft survival duration according to rifampin usage, and we evaluated the factors that could influence the duration time until the recurrence of TB. Seventy-eight TB patients diagnosed after kidney transplantation were studied. Pulmonary TB was diagnosed in 26 of the 78 patients (33.3%), pleural TB in 23 (29.5%), combined pulmonary and pleural TB in 5 (6.4%), miliary TB in 19 (24.4%), and intestinal TB in 2 patients. In the pulmonary (pulmonary TB and pleural TB) TB group, no differences in graft survival and the TB free duration period were observed between the rifampin usage subgroup and the non-rifampin usage subgroup. In the extrapulmonary TB group, no difference was found in mean graft survival time between the rifampin usage subgroup and the non-rifampin usage subgroup, but the rifampin usage subgroup showed that the TB had a tendency to recur later than for the non-rifampin usage subgroup (87 +/- 8 vs. 44 +/- 7 months, respectively, p=0.30). The factor affecting the duration period until the recurrence of TB was the treatment duration (RR=0.761, p=0.030). This study suggests that rifampin does not affect graft survival in renal transplant recipients in whom immunosuppression is carefully monitored. Also, the study results indicate that rifampin may prevent a recurrence of extrapulmonary tuberculosis. Prolonged treatment appears to be appropriate for renal transplant recipients with TB.