A previously healthy 25-year-old woman presented with headache, dysarthria, double vision, and dizziness for 1 week. She denied any history of fever, head trauma, vomiting, diarrhea, abdominal pain, or cough. She had traveled to northeastern Brazil 2 months before the onset of the neurological symptoms.
On examination, she had a mild right-side hemiparesis with hyperreflexia and hemiataxia. She could walk unassisted but presented with a broad base. There were no meningeal signs. She did not present with hepatosplenomegaly of lymphadenopathy. Her cranial magnetic resonance imaging showed a T2-weighted fluid-attenuated inversion recovery hyperintense lesion with heterogeneous gadolinium enhancement in the pons (Figure). There were no signs of diffusion restriction on diffusion-weighted imaging or hemorrhages on susceptibility-weighted imaging.