[Thymoma complicated with miliary tuberculosis]

We report a case of thymoma complicated with miliary tuberculosis. A 69-year-old woman was admitted to a hospital because of body weight loss, general fatigue, and dyspnea. Chest X-ray showed a small, diffuse granular shadows in both lungs. Biopsied-specimens from bone marrow and left pharynx revealed granuloma with both giant cells and caseous necrosis. The diagnosis of miliary tuberculosis was made. The patient was then transferred to our hospital. Both chest X-ray and computed tomography conducted on admission revealed a mass in the mediastinum as well as diffuse granular shadows in both lungs. We suspected a presence of thymoma. Anti-tuberculosis therapy was started, and extended thymectomy was performed. The diagnosis of thymoma was confirmed pathologically. Immunological analysis of peripheral blood lymphocytes was done before and after the operation. Negative conversion of PPD reaction was observed after thymectomy. Although the response of peripheral lymphocytes to phytohaemoagglutinin (PHA) and concanavalin A recovered after thymectomy, a marked decrease of the number of CD 4 T cells, a decrease of T helper 1 cells, a slight increase in the number of B cells and cells expressing natural killer cell-related surface markers were observed throughout the course of illness.