Brain MRI showed multiple diffusely increased T2/FLAIR signal abnormalities with enhancement in the bilateral cerebral hemispheres, confluent hyperdense lesions at the gray-white junction across the bilateral frontal and temporal lobes. Cerebrospinal fluid (CSF) analysis showed elevated protein without pleocytosis. Microbiological testing for a wide array of bacterial, viral and fungal pathogens was unremarkable, as was testing for heavy metals, paraneoplastic and autoimmune antibodies and free light chains.

After treatment with intravenous methylprednisolone and PLEX, patient showed significant improvement.

Three months after the initial clinical presentation, the patient’s cognitive-linguistic skills were improved in all measured domains. Both brain MRI (6/10/24) and EEG (5/13/24) showed remarkable improvement.

In patients presenting with encephalitis-like symptoms, an extensive history should be taken regarding supplement and drug use, especially among people with recent travel to countries endemic for parasitic infections, where it is available with or without a prescription. Although levamisole-adulterated cocaine has been more commonly seen in the US, clinicians should also be aware of sole ingestion of levamisole as a possible cause of encephalopathy.