Clinical aspects of CNS cysticercosis.

Central nervous system cysticercosis, caused by infection with the larva of the pork tapeworm, is common throughout the world. Infection occurs after ingestion of fecal contaminants containing the ova of Taenia solium. The clinical manifestations depend on the number, age, and location of the larval cysts disrupting neural tissues. Several disease patterns are apparent: (1) basilar cysticercosis resulting in chronic meningitis or progressive hydrocephalus, (2) parenchymal cysts with focal symptoms, (3) diffuse parenchymal cysts with intracranial hypertension, (4) ventricular localization with episodic acute hydrocephalus, and (5) spinal cord cysticercosis mimicking mass lesions. Mixtures of these basic patterns may occur, and asymptomatic infections are common. In the United States, meningeal cysticercosis is often mistaken for tuberculous or fungal meningitis. A diagnosis of CNS cysticercosis should be considered in any patient with these syndromes who has resided in an area of high prevalence of T solium.