- Chronic granulomatous disease (CGD) is a primary immunodeficiency disease symptomized by failure to generate superoxide and recurrent bacterial and fungal infections. Allogeneic bone marrow transplantation (BMT) is one of the therapeutic options available. However, it presents considerable risk to the recipient, especially if the patient is already at an advanced stage of disease, after repeated bacterial and fungal infections and organ damage. We present a case report of a 6-year-old child with long-standing CGD, severe clubbing, and jeopardized pulmonary function after multiple bacterial pulmonary infectious episodes, who had failed treatment with sulphamethazole trimethoprim, multiple antibiotic courses, itraconazole, as well as steroid and interferon-y therapy. He underwent allogeneic peripheral blood stem cell transplantation (alloPBSCT) from his HLA-matched MLC non-reactive sister following non-myeloablative conditioning. His ANC did not fall below 0.2 x 10(9)/l, his lowest WBC was 0.6 x 10(9)/l, and his platelets did not fall below 28 x 10(9)/l. He had normal engraftment, with no mucositis or organ toxicity. Neither parenteral nutrition nor platelet infusions were necessary. Partial donor chimerism following alloPBSCT was converted to full donor chimerism and superoxide production reverted to normal after donor lymphocyte infusions (DLI) from his HLA-matched sister. Twenty four months post transplant the patient is well, with stable and durable engraftment, 100% donor chimerism, normal superoxide production, no GVHD, and stabilization of his pulmonary condition. We suggest that alloPBSCT preceded by non-myeloablative conditioning and followed by DLI may constitute a successful mode of therapy for patients suffering from advanced CGD with recurrent infectious episodes resulting in organ dysfunction, enabling them to achieve full donor chimerism and normal superoxide production with minimal risk of transplant-related toxicity and GVHD.