Incidence and Outcomes of Tuberculosis among Thoracic Organ Transplant Recipients in an Endemic Country - 15 Years of Evaluation

Purpose Tuberculosis (TB) is an endemic disease in Brazil. Therefore, it demands a higher surveillance regarding donors and receptors. Reactivation of latent TB infection (LTBi), new cases of TB and “de novo” TB may occur. For this reason, we revised all cases of post-transplant tuberculosis, and their outcomes, reported in the last 15 years in our heart and lung transplant center. Methods We conducted a retrospective review of medical records between January/2005 - June/2020 of all TB infection and LTBi in thoracic organ transplant recipients in our center at Sao Paulo, Brazil. Diagnosis was done after biopsy, culture or positive smear microscopy at affected sites, except for pleural tuberculosis, when diagnosis was given by the analysis of pleural effusion. Results In this period, 872 thoracic organ transplants were performed: 484 heart transplant (HTx) and 388 lung transplants (LTx). Eighteen recipients had LTBi and received treatment with isoniazid for 6 months: 1 HTx and 17 LTx recipients. Among those, 11 had confirmed previous pulmonary TB and 8 of them had LTx indication for bronchiolitis due to TB sequela. The other patients, received LTBi treatment because: 4 cases of positive Manteaux test, 1 post-exposure and 2 with donor previous treated Pulmonary TB.Post-transplant TB infection was diagnosed in 21 patients (2,4%): 14 LTx and 7 HTx. There sites were 11 pulmonary, 3 donor-derived pulmonary, 3 pleural, 3 ganglionary and, 1pericardium. All patients, until 2013, were initially treated with regular 4-drugs treatment (rifampin+isoniazid+pyrazinamide+ethambutol) however due to great interaction with calcineurin inhibitors, treatment was changed to rifampin-free scheme for 12 months. There were no changes in the immunosuppression. One patient had elevation of liver enzymes and other 2 patients reported nausea and vomiting. Crude mortality was 19% (4 patients). Conclusion We observed higher risk (almost 3 times) for TB infection among LTx recipients compared to HTx patients. Extra-pulmonary TB infection was frequent among HTx recipients in contrast with pulmonary TB presentation in LTx recipients. Treatment for LTBi with isoniazid was effective, since no patient had recurrence of tuberculosis.Our data suggest the importance of active surveillance for TB infection or LTBi in thoracic organ transplant center in endemic countries.