Mycobacterial spindle cell pseudotumor of the brain - A case report and review of the literature

Spindle cell pseudotumors found in the skin, lymph nodes, bone marrow, sple en, lungs, and retroperitoneum have been reported recently in immunosuppres sed patients, including those with acquired immunodeficiency syndrome. The authors report a similar lesion limited to the brain in a 38-year-old human immunodeficiency virus-negative man receiving steroid therapy for treatmen t of sarcoidosis. Histopathologically the lesions were composed of spindle and epithelioid histiocytes, small foci of necrosis, and numerous acid-fast bacilli. The acid-fast bacilli were determined by culture and polymerase c hain reaction to be Mycobacterium avium intracellulare. Because of the unco mmon histologic appearance of this lesion and the potential for treatment i f recognized, mycobacterial spindle cell pseudotumors should be included in the differential diagnosis of spindle cell lesions in the brain in immunos uppressed patients.