What are the complications of Neurocysticercosis (NCC)?

Complications of Neurocysticercosis

The two most common and clinically significant complications of neurocysticercosis are seizures (occurring in 70-90% of symptomatic patients) and increased intracranial pressure from obstructive hydrocephalus (occurring in approximately 20% of cases). 1, 2

Major Neurological Complications

Seizure Disorders

• Epilepsy is the predominant complication, with NCC causing approximately 29% of seizures in endemic areas and representing the leading cause of late-onset epilepsy worldwide 1, 2
• Seizures can manifest as focal, focal with secondary generalization, or generalized seizures 1
• The seizure risk persists even after cyst resolution, as calcified lesions can serve as ongoing epileptogenic foci 2, 3

Increased Intracranial Pressure

• Obstructive hydrocephalus occurs in approximately 20% of NCC cases, primarily from ventricular or cisternal involvement 1
• When hydrocephalus develops secondary to cysticercotic meningitis, the mortality rate reaches 50%, with most patients dying within 2 years despite CSF shunting 2
• Acute intracranial hypertension can be life-threatening, particularly with intraventricular cysts 2, 4

Location-Specific Complications

Ventricular and Cisternal Disease (Malignant Forms)

• Ventricular and basal cisternal locations are considered malignant forms of NCC due to high morbidity and mortality 2
• Racemose cysts in basal cisterns cause intense inflammatory reaction, fibrosis, and progressive leptomeningeal thickening at the brain base 2
• CSF circulation obstruction occurs in approximately 60% of cases with cisternal involvement 2

Subarachnoid Space Involvement

• Giant cysts can develop in the Sylvian fissure, causing intracranial hypertension, hemiparesis, partial seizures, or other focal neurological signs 2
• Chronic arachnoiditis can develop, leading to progressive neurological deterioration 5, 6

Spinal Involvement

• Spinal cord or nerve root compression can occur with intramedullary or extramedullary cysts 4, 6
• Radiculopathies may develop as a less common manifestation 1

Cerebrovascular Complications

• Cerebrovascular accidents can occur, including lacunar infarctions, thrombotic strokes, and hemorrhagic strokes 1
• Arteritis secondary to inflammatory response around cysts can lead to ischemic cerebrovascular disease 6

Ophthalmologic Complications

• Retinal involvement represents a critical complication that requires fundoscopic examination before initiating anthelmintic therapy 1, 7
• Intraocular cysts can cause visual changes and potential retinal damage, particularly if antiparasitic treatment causes inflammatory destruction of the parasite 7

Cognitive and Psychiatric Complications

• Dementia can develop, particularly with chronic or extensive disease 6
• Psychic complaints and cognitive impairment may occur with chronic brain involvement 5
• Headaches, including migraine-type headaches, are common manifestations 1, 8

Treatment-Related Complications

Inflammatory Response to Antiparasitic Therapy

• Neurological symptoms can worsen during treatment due to inflammatory reaction from parasite death within the brain 7
• Cerebral hypertensive episodes, seizures, and focal neurologic deficits may occur after initiating therapy, necessitating prophylactic corticosteroids and anticonvulsants 7

Medication Toxicity

• Bone marrow suppression, including granulocytopenia, pancytopenia, aplastic anemia, and agranulocytosis can occur with albendazole, with fatalities reported 7
• Hepatotoxicity with mild to moderate liver enzyme elevations occurs in approximately 16% of patients, with rare cases of acute liver failure 7

Chronic Complications

• Chronic brain edema can persist as a long-term complication 5
• Calcified lesions remain as permanent sequelae and can serve as ongoing epileptogenic foci 2, 3
• Impaired fourth ventricle syndrome may develop in specific cases 5

Critical Pitfalls to Avoid

• Do not overlook the possibility of asymptomatic disease—patients can harbor viable cysticerci without symptoms until the parasite dies and triggers massive antigen exposure 6
• Always perform fundoscopic examination before starting antiparasitic treatment to identify retinal lesions that could be damaged by treatment-induced inflammation 1, 7
• Screen for undiagnosed neurocysticercosis in patients from endemic areas being treated for other conditions, as treatment may unmask previously asymptomatic NCC 7
• Recognize that CSF may be completely normal even with viable cysticerci present, so normal CSF does not exclude the diagnosis 5