How do I diagnose and treat neurocysticercosis?

Neurocysticercosis: Diagnosis and Treatment

Diagnostic Approach

Diagnose neurocysticercosis using both brain MRI and non-contrast CT scan combined with enzyme-linked immunotransfer blot (EITB) serology for confirmation. 1, 2, 3

Imaging Studies

• Obtain both MRI and CT scan to determine the number, location, stage, and viability of cysts—MRI is superior for detecting small lesions and extraparenchymal disease, while CT is better for identifying calcifications 1, 2, 3
• The imaging findings will guide your entire treatment strategy, as management differs dramatically based on cyst location (parenchymal vs. extraparenchymal), number, and stage 1, 4

Serologic Testing

• Use enzyme-linked immunotransfer blot (EITB) as the confirmatory test—this has superior sensitivity and specificity compared to other serologic methods 1, 2
• Avoid enzyme-linked immunosorbent assays (ELISA) using crude antigen due to poor sensitivity and specificity 1, 2

Pre-Treatment Mandatory Evaluations

Before initiating any anthelmintic therapy, complete these critical steps:

• Perform fundoscopic examination to rule out intraocular cysticerci—antiparasitic drugs can cause blindness if ocular cysts are present 1, 2, 3
• Screen for latent tuberculosis infection in patients who will require prolonged corticosteroids 1, 2, 3
• Screen or provide empiric therapy for Strongyloides stercoralis in patients requiring prolonged corticosteroids to prevent hyperinfection syndrome 1, 2

Treatment Algorithm

Step 1: Assess for Contraindications to Antiparasitic Therapy

Do NOT give antiparasitic drugs if the patient has:

• Untreated hydrocephalus 1, 3
• Diffuse cerebral edema 1, 3
• Intraocular cysticerci (requires surgical removal instead) 1, 3

In these cases, manage elevated intracranial pressure first with anti-inflammatory therapy and/or surgical intervention 1, 3

Step 2: Determine Treatment Based on Cyst Burden

For 1-2 Viable Parenchymal Cysts:

• Albendazole monotherapy: 15 mg/kg/day divided into 2 daily doses (maximum 1200 mg/day) for 10-14 days 2, 3
• Administer with food to enhance absorption 2

For >2 Viable Parenchymal Cysts:

• Combination therapy: Albendazole 15 mg/kg/day PLUS praziquantel 50 mg/kg/day for 10-14 days—this combination demonstrates superior radiologic resolution compared to albendazole alone 2, 3

Step 3: Concurrent Corticosteroid Therapy

• Administer corticosteroids concomitantly with antiparasitic agents to minimize inflammation and cerebral edema associated with parasite death 3, 5
• This is a strong recommendation due to the risk of worsening symptoms during treatment 3

Step 4: Antiepileptic Drug Management

• Initiate antiepileptic drugs for seizure control in patients presenting with seizures 2, 3
• Continue antiepileptic drugs for at least 2 years if seizure-free and cysts resolved 3

Monitoring During Treatment

• Monitor blood counts at the beginning of therapy and every 2 weeks while on albendazole to detect hepatotoxicity and leukopenia 1, 2
• No additional monitoring is needed for combination therapy beyond what is recommended for albendazole monotherapy 1

Follow-Up Protocol

• Repeat MRI at least every 6 months until complete resolution of the cystic component 1, 2, 3
• Consider retreatment if parenchymal cysts persist >6 months after initial therapy 3

Special Populations

Pregnant Women:

• Defer antihelminthic therapy until after delivery—antihelminthic drugs are rarely required emergently 1, 3
• Aggressively manage elevated intracranial pressure as you would in non-pregnant patients 1
• Corticosteroids can be used when necessary 1
• Avoid phenobarbital and valproic acid due to high teratogenicity rates 1
• Avoid methotrexate as it is teratogenic 1

Children:

• Manage identically to adults using weight-based dosing—there is no evidence that management should differ 1, 3

Public Health Considerations

• Screen household members for tapeworm carriage in patients who likely acquired neurocysticercosis in a non-endemic area—this is a public health issue that can be addressed by the local health department 1, 2

Critical Pitfalls to Avoid

• Never start antiparasitic therapy without fundoscopic examination—missing ocular involvement can result in blindness 1, 2, 3
• Never treat patients with untreated hydrocephalus or diffuse cerebral edema with antiparasitic drugs—manage the elevated intracranial pressure first 1, 3
• Never use ELISA with crude antigen for diagnosis—it has poor sensitivity and specificity 1, 2
• Never forget corticosteroids when giving antiparasitic drugs—parasite death causes significant inflammation 3, 5