UCSF

BACKGROUND: Neurocysticercosis (NCC) is the most common parasitic infection of the central nervous system and is typically diagnosed through visualization of the cysts in the cerebral parenchyma by neuro-imaging. However, neuro-imaging may not detect extraparenchymal neurocysticercosis (EPNCC), which is a rare manifestation of the disease involving the subarachnoid, meningeal, and intraventricular spaces. We report 2 cases of extraparenchymal neurocysticercosis, and discuss the diagnostic challenges and management of this entity. METHODS: Two cases were identified through clinical records. RESULTS: Both patients had an insidious onset with slow progression of disease, and presented with papilledema and cerebrospinal fluid (CSF) eosinophilia. One case was diagnosed with spinal cord biopsy. The other was diagnosed with CSF serology and next-generation sequencing-based pathogen analysis. Both patients were treated with ventriculoperitoneal shunt, systemic antiparasitic agents, and immunosuppression. CONCLUSIONS: EPNCC is less common than parenchymal NCC. A high level of clinical suspicion is required given its rarity, long incubation period, and slow progression. Diagnosis and treatment can be challenging and requires a multidisciplinary approach.