Mycobacterium tuberculosis: Active disease and latent infection in a renal transplant cohort.

BACKGROUND: Tuberculosis (TB) is a serious opportunistic infection in renal transplant recipients associated with high mortality. Screening and treatment of latent Mycobacterium tuberculosis infection (LTBI) offers an opportunity to prevent subsequent active disease.

METHODS: We retrospectively reviewed the records of all adult patients who underwent renal transplantation at our centre from 2005 to 2014 to assess current screening practices, the risks for and burden of active TB.

RESULTS: A total of 660 individuals underwent renal transplantation during this period, totalling 3647 person years of follow up. Three patients were diagnosed with active TB after renal transplant, resulting in an incidence of 82 per 100,000 person-years. Of 656 transplant recipients, 102 (15.5%) were born in high TB incidence countries and 89 (13.5%) had an interferon gamma release assay (IGRA) at any point. Individuals born in high TB risk countries had a much higher incidence of active TB (530 per 100,000 person-years). Ten individuals had positive IGRA tests, of whom two were treated for active TB, two received chemoprophylaxis and six were not treated.

CONCLUSIONS: In the absence of formal guidelines, IGRA-based screening for LTBI was infrequently performed. Our data suggests that screening and treatment of renal transplant recipients born in high incidence countries is an important preventive measure.