Cysticercosis and neurocysticercosis
Cysticercosis is tissue infection with the larval stage of Taenia solium, acquired by ingesting eggs shed in the feces of a human tapeworm carrier, and neurocysticercosis, its central nervous system form, is the leading cause of acquired epilepsy worldwide, diagnosed by neuroimaging and serology and treated with albendazole plus a glucocorticoid for viable cysts only.
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What this article covers
- Overview
Cysticercosis is tissue infection with the larval stage (cysticercus) of Taenia solium, acquired by ingesting eggs, not by eating undercooked pork: the eggs come from a human carrier of the…
- Epidemiology
Endemic wherever free-ranging pigs have access to human feces, sustaining the Taenia solium life cycle: Latin America, South and Southeast Asia, and sub-Saharan Africa carry the highest burden.
- Risk factors
Household or close contact with a person who has intestinal Taenia solium taeniasis: living with, or eating food prepared by, an infected household member is the principal risk, regardless of the exposed person's own pork consumption.
- Pathophysiology
Ingested Taenia solium eggs hatch in the small intestine, releasing larvae (oncospheres) that penetrate the bowel wall and disseminate hematogenously: distinct from taeniasis, in which ingested…
- Clinical features
Seizure is the most common presentation, reflecting a parenchymal cyst with surrounding inflammation or a calcified epileptogenic focus: new-onset seizure in a patient with endemic residence, travel…
- Differential diagnosis
Primary central nervous system lymphoma: a single, well-demarcated, periventricular white matter lesion, typically in an immunocompromised host; MRI appearance and biopsy distinguish it from multiple cystic or calcified lesions.
- Diagnosis
The diagnosis of neurocysticercosis is established by characteristic neuroimaging (multiple cystic or calcified brain lesions, sometimes with a visible scolex) supported by serum or CSF serology…
- Management
First, manage active seizures and any signs of raised intracranial pressure before addressing the parasite itself, using standard antiepileptic therapy and, for significant edema or hydrocephalus, glucocorticoids or neurosurgery as needed.
- Complications
Hydrocephalus from intraventricular or subarachnoid cyst obstruction of CSF flow: a leading cause of morbidity, sometimes requiring permanent ventricular shunting.
- Prognosis
Solitary viable parenchymal cysticercosis generally has a favorable prognosis with antiparasitic treatment and seizure control, though some patients need ongoing antiepileptic therapy after the parasite clears.
- Prevention
Identification and prompt treatment of intestinal tapeworm carriers interrupts transmission to household contacts: treating known taeniasis with praziquantel 5 to 10 mg/kg PO as a single dose (see…
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