Isolated meningeal vasculopathy associated with Clostridium septicum infection.

A 28-year-old patient with acute lymphoblastic leukemia and neutropenia developed necrotizing enterocolitis and Clostridium septicum bacteremia, followed by rhabdomyolysis, skin rash, and acute neurologic changes. Numerous cortical leptomeningeal enhancements were present on head MRI. Meningeal and brain biopsy showed segmental, full-thickness lysis of smooth muscle cells of medium-sized meningeal vessels with overall preservation of the structure of the vessel wall.