Pulmonary miliary tuberculosis and T-cell abnormalities in a severe combined immunodeficient patient reconstituted with haploidentical bone marrow transplantation.

We report the development of miliary tuberculosis in a 7-year-old boy with severe combined immunodeficiency (SCID), whose immune system had been only partially reconstituted by haploidentical bone marrow transplantation. Although alpha beta and gamma delta T cells were of donor origin, alpha beta T cells in this patient showed defective interleukin-2 (IL-2) production, impaired IL-2 responsiveness and decreased cytolytic activity. However, gamma delta T cells could exhibit enough cytolytic activity after incubation with IL-2. Despite the presence of disseminated infection, C-reactive protein (CRP) remained negative. IL-2 therapy aggravated the disseminated tuberculosis though gamma delta T cells were supposed to be activated, and concurrently CRP became positive. These findings suggest that gamma delta T cells have no more than limited immunological roles in mycobacterium tuberculosis infection.