INCIDENCE OF TUBERCULOSIS AFTER BONE-MARROW TRANSPLANTATION IN A SINGLE-CENTER FROM TURKEY

Tuberculosis (TB) is generally seen in immunodeficient states and its incidence would be expected to increase after hematopoietic stem cell transplantation (SCT), particularly in the allogeneic setting. However , recent reports from developed countries did not support this hypothe sis. Turkey is one of the countries where the disease is endemic. Over a period of 10 years two cases of TB among 120 allogeneic and 65 auto logous bone marrow or peripheral blood SCT were encountered. The first patient was a 42-year-old male with acute nonlymphoblastic leukemia ( ANLL) who underwent allogeneic SCT from his HLA-identical sister in fi rst remission. His early post transplant period was unremarkable and s howed no clinical acute or chronic graft versus host disease (GVHD). H is chest X-ray and CT scan revealed alveolar infiltrate of the left ap ical lobe one year after the procedure and sputum showed acid-fast bac illi, later identified as Mycobacterium tuberculosis. He was put on co mbination chemotherapy. He is now well and disease-free 30 months afte r transplant with no complaints of pulmonary TB. The second patient wi th chronic phase CML underwent allogeneic peripheral SCT from his HLA- identical sister. He suffered from,grade II acute and extensive chroni c GVHD partially treated with immunosuppressive therapy. He showed pul monary TB 15 months after transplantation. He is still on combination chemotherapy. Although our numbers are small, the annual incidence of TB after SCT is 1.1% (2/185) which is nearly 30 to 40 times higher tha n the incidence of TB in the general Turkish population. In other word s, an immunosuppressive state after allogeneic SCT seems to increase t he risk of TB in Turkey. In conclusion, TB should be considered in the differential diagnosis of unexplained infections after SCT, especiall y in countries, where the disease is endemic.