Deficiency of immunity to Mycobacterium avium that can be restored by allogeneic lymphocytes.

A 3-year-old girl developed a disseminated Mycobacterium avium infection despite treatment with eight antimycobacterial drugs. She had no pre-existent general humoral or cellular immunodeficiency. In the course of the disease B lymphocyte areas in the lymphoid tissues were replaced by histiocytes and an IgM and IgA deficiency evolved. The patient still made antibodies to concomitant micro-organisms and to transfused blood cells. Peripheral blood mononuclear cells (PBMC) had normal responses to mitogens and various antigens in vitro. However, she lacked any response to mycobacterial antigens, in vivo and in vitro. The defect appeared not to be dependent on immunosuppression by lymphocytes or monocytes or on deficient antigen presentation by monocytes. because a genetic origin could not be substantiated, acquired immunological paralysis for mycobacterial antigens was the most likely explanation. Addition of irradiated PBMC from her HLA-A, -B, -C and -DR phenotypically identical father, transferred a response to mycobacterial antigens of the patient's PBMC in vitro. We concluded that the disseminated M. avium infection was accompanied by a selective deficiency of the lymphocyte response to mycobacterial antigens which could be restored by allogeneic antigen responsive lymphocytes.