Clinical aspects of neurocysticercosis

The clinical features of neurocysticercosis (NCC) largely depend on the number, type, size, localization and stage of development of cysticerci, as well as on the host immune response against the parasite. Seizures are widely reported to be the most common symptom, occurring in 70–90% of patients, while NCC is considered to be the main cause of late-onset epilepsy in endemic areas. When cysticerci lodge within the ventricular system, life-threatening acute intracranial hypertension secondary to hydrocephalus may develop. Cysts in the subarachnoid space may invade the Sylvian fissure and grow to large sizes (giant cysts) causing intracranial hypertension with hemiparesis, partial seizures or other focal neurological signs. Racemose cysts in the basal cisterns can cause an intense inflammatory reaction, fibrosis and progressive thickening of the leptomeninges at the base of the brain. In approximately 60% of the cases, there is an obstruction of the cerebrospinal fluid (CSF) circulation, resulting in hydrocephalus and intracranial hypertension. When hydrocephalus secondary to cysticercotic meningitis is present, the mortality rate is high (50%) and most patients die within 2 years after CSF shunting. Therefore, ventricular and basal cisternal locations are considered to be malignant forms of NCC. The diagnosis of NCC is based upon neuroimaging studies, laboratory analysis of the CSF and antibody detection in the serum. Nowadays, albendazole is considered the medication of choice for the therapy of NCC. Its main use is for symptomatic patients showing multiple viable brain parenchymal cysticerci.