Teaching NeuroImages: brucellosis mimicking demyelinating disease.

A 57-year-old man presented with a 4-week history of fever, visual loss, and progressive ataxic gait. He worked as a truck driver and had been in contact with raw sheepskin a few months prior. Neurologic examination showed drowsiness, pseudobulbar syndrome, hyperreflexia, ataxia, and optic disc edema. He had a lymphocytic pleocytosis and diffuse hyperintense white matter lesions on brain MRI (figure). Serum and urine PCR were positive for Brucella spp. Rheumatologic and other serologic tests were negative. Partial improvement was achieved with doxycycline, rifampin, and trimethoprim-sulfamethoxazole. Brain MRI suggesting demyelinating disease with atypical clinical presentation should raise other diagnostic possibilities such as nervous system infections and acute disseminated encephalomyelitis.1,2