Multifocal neutrophilic meningoencephalitis: a novel disorder responsive to anakinra.

We report a 57-year-old man with recurrent meningoencephalitis resulting in bouts of altered consciousness, encephalopathy, tremors, focal seizures, and paraparesis. The neurological manifestations were accompanied by fever and leukocytosis in the absence of other systemic manifestations. MRI abnormalities of the brain, brainstem, spinal cord and meninges and CSF pleocytosis and elevated protein were observed. Exhaustive studies failed to reveal an etiology. Brain biopsy revealed nodules of neutrophils and macrophages, but no vasculitis. The lesions were not vasocentric as would be expected with neuro-Behcet's disease and neuro-Sweet's disease. The disorder was responsive to high-dose corticosteroid therapy and, ultimately, to anakinra, an IL-1α and IL-1β receptor antagonist.