Abstract
We report a case of subcutaneous abscess caused by Nocardia farcinica in a 44-year-old man, who had been treated with systemic prednisolone and cyclosporin for aplastic anemia. He had been affected by aplastic anemia for 8 years, and was previously treated with antithymocyte globulin. The effect was insufficient, and platelet and erythrocyte transfusion was required. Bone marrow transplantation was not adopted due to a psychological problem. He had also been treated with prednisolone and cyclosporin for 3 years. Without apparent cause, swelling and pain of left upper extremity developed in April, 2008. There was no abnormality in cutaneous macroscopic findings, such as a wound or a sting. He was administered antibiotics, but they were ineffective and effusion were excreted into the skin. After hospitalization, he was treated by incision and drainage and antibiotics were started. The pathogen was identified as Nocardia farcinica by its biochemical characters. There was no dissemination to other organs like lung or brain and he recovered completely with a treatment of antibiotics for 1 year. We studied the epidemiological and clinical characteristics of Nocardia infections reported in Japan from 2000 to 2008 and identified 92 cases using the medical article search engine Ichushi-Web (Japan Medical Abstract Society). The results indicate that the most important risk factor in systemic nocardiosis ia an immunosuppressive agent such as prednisolone, cyclosporine, or azathioprine. We believe that we should take the possibility of Nocardia infection into consideration in a compromised host.