[Anterior Mediastinal Cholesterin Granuloma Associated with Bilateral Pleurisy and Pericarditis].

The patient was a 41-year-old man. He was diagnosed with pleurisy and came to our hospital. The pleural effusion and pleurisy remained even after administration of sufficient doses of antibiotics. A thorough examination revealed an anterior mediastinal tumor. Six months later, pericarditis also developed. Autoimmune diseases, infections, and malignant diseases were suspected, but a definitive diagnosis could not be made. In order to confirm the diagnosis, anterior mediastinal tumor resection and pleural biopsy were performed. The anterior mediastinal tumor was diagnosed as cholesterin granuloma pathollogically. Cholesterin granuloma is a granuloma formed by deposition of cholesterin crystals and cholesterin granuloma occurring in the mediastinum is extremely rare.