Background: Spindle cell pseudotumors may occur due to mycobacterial infection, especially in immunocompromised hosts including those with AIDS. They have been reported from many body sites; the lymph nodes are predominantly involved, most frequently associated with Mycobacterium avium complex infection. To the best of our knowledge, Mycobacterium-associated spindle cell pseudotumors have not been previously described in the brain stem and in association with mixed mycobacterial infection.
Case report: We describe a man with AIDS who presented with right hemiparesis and truncal ataxia. Magnetic resonance imaging revealed enhancing nodular lesions at the cerebral peduncle and medulla. A mycobacterial spindle cell pseudotumor was diagnosed on surgical specimens. Blood and brain tissue cultures grew Mycobacterium haemophilum and Mycobacterium simiae.
Conclusions: To our knowledge, this is the first case of spindle cell pseudotumor of the brain associated with M. haemophilum and M. simiae mixed infection.