To describe a case of neurotoxocariasis and review the literature.

Neurotoxocariasis is rare complication of toxocariasis, a zoonosis caused by accidental ingestion of toxocara eggs. In neurotoxicariasis, migrating larvae cross the blood brain barrier. Presentations have included meningitis/encephalitis, seizures, myelitis, or the course may be indolent. Presentations can mimic neurologic tuberculosis, neurocysticercosis, fungal infections, demyelinating conditions, and CNS lymphoma. 

A single patient chart review and literature review was performed.

A 14-year-old male with a history of Angelman syndrome, duplication of 1q21.1q21.2, and epilepsy presented with breakthrough seizures, gradual worsening of baseline imbalance, and lower extremity hyperreflexia. Brain and spine MRI with and without contrast was notable for too numerous to count punctate and small foci of enhancement with slightly larger associated foci of T2/FLAIR signal abnormality throughout cerebral and cerebellar hemispheres and spinal cord. Initial differential included autoimmune, other demyelinating, infectious, and genetic causes. Initial CSF findings only notable for elevated oligoclonal bands. Serum eosinophilia of 2.6 was present. He was initially treated with high dose IV methylprednisolone with oral taper due to concern for an autoimmune process, with some mild improvement in balance. MRI repeated 2 months later demonstrated increased size and number of lesions. Expanded extensive infectious disease testing was unrevealing aside from strongly positive serum antibodies to Toxocara. He was treated with albendazole for 3 weeks and prednisone for 6 weeks with full resolution of spinal lesions and almost complete resolution of the lesions on brain MRI.

Neurotoxocariasis is a rare opportunistic infection more common in areas of poor sanitation or in children with oral fixation. MRI findings include punctate monofocal or polyfocal T2/FLAIR hyperintense lesions with marked contrast enhancement. Treatment for children is albendazole 15 mg/kg for children (800 mg daily max) for 21–28 days and steroid taper. Other diagnoses can mimic neurotoxocariasis.