Mycobacterium tuberculosis infection in allogeneic bone marrow transplantation patients

Bone marrow transplant (BMT) recipients are prone to bacterial, viral and f ungal infections, Mycobacterium tuberculosis infection can occur in these p atients, but the incidence is lower than that of other Infections. This rep ort describes four patients with Mycobacterium tuberculosis infection ident ified from 641 adult patients who received a BMT over a 12-year period (pre valence 0.6%). The pre-transplant diagnosis was AML in two patients and CML in the other two, Pre-transplant conditioning consisted of BU/CY in three patients and CY/TBI in one. Graft-versus-host disease (GVHD) prophylaxis wa s MTX/CsA in three patients and T cell depletion of the graft in one patien t, Sites of infection were lung (two), spine (one) and central nervous syst em (one). Onset of infection ranged from 120 days to 20 months post BMT. Tw o patients had co-existing CMV infection. One patient had graft failure. Th e two patients who received anti-tuberculous (TB) therapy recovered from th e infection. Although the incidence of tuberculosis in BMT patients is not as high as in patients with solid organ transplants, late diagnosis due to the slow growth of the bacterium can lead to delay in instituting anti-TB t herapy. A high index of suspicion should be maintained, particularly in end emic areas.