Sections of the cerebellum show necrotizing granulomatous inflammation. There are well-defined crowded granulomas, comprising nodular aggregates of epithelioid histiocytes and multinucleated giant cells. Areas of necrosis are seen in the neuropil. The granulomas are surrounded by lymphocytes, plasma cells and some neutrophils. No tumor is identified. The Gram stain shows no bacteria. The Grocott stain shows no fungi. The Ziehl-Neelsen stain shows two acid fast bacilli, in keeping with mycobacterial infection.
Necrotizing granulomatous inflammation with acid fast bacilli, in keeping with mycobacterial infection (tuberculoma)