Prevalence, risk factors and Impact of Post-transplant Tuberculosis on Live Donor Kidney Transplant Recipients: A Retrospective Study

Background: TB is encountered worldwide more frequently among renal transplant recipients than in the general population. It is reported to be nearly 50 times higher in the renal transplant population because of immunosuppression. TB may arise from unrecognized infection in the allograft or acquisition of new infection after transplantation. Objective: The aim of the current work was to determine prevalence and risk factors for development post-transplant TB, and the impact of post-transplant TB in live donor renal transplantation on both patient and graft survival. Patients and methods: This retrospective cohort study carried out in the Nephrology Unit, Mansoura Urology and Nephrology Centre in Association with Nephrology Unit, Zagazig University Hospitals in the period between January 2020 to December 2020. Included 210 patients out of 3200 kidney transplant recipients (KTRs) who underwent renal transplantation in the period between March 1976 and December 2019, divided into 2 main groups according to development of post-transplant tuberculosis, a group of 70 (KTRs) who developed tuberculosis after transplantation served as a study group and a matched group of 140 (KTRs) who did not develop tuberculosis after transplantation served as control group and evaluation of two groups through risk factor to develop TB, demographical data, clinical, laboratory and radiological evaluation. After that TB group was subdivided into 2 groups according to the site of infection: pulmonary and urinary TB. Results: Body mass index was higher among control group with statistically significant difference. Associated medical disorders as post-transplant diabetes, post-transplant bacterial and CMV infection had higher incidence among TB group. Liver enzymes and calcineurin (CNI) levels showed statistically significant difference among TB group before and during anti tuberculous treatment, in which liver enzymes were elevated while CNI levels were significantly reduced during antituberculous treatment. Post- transplant CMV infection was higher in patients who developed pulmonary TB. Graft and patient survival were comparable among both groups with no significant difference. Conclusions: It could be concluded that post-transplant diabetes, bacterial and CMV infections increase risk of development of post-transplant TB. There was no effect of post-transplant tuberculosis on both patient and graft survival.