What is the treatment for parasitic infections associated with eosinophilia?

Treatment of Parasitic Infections Associated with Eosinophilia

The treatment of parasitic infections associated with eosinophilia requires specific antiparasitic medications targeted to the causative organism, with albendazole, ivermectin, and praziquantel being the most commonly used first-line agents depending on the specific parasite identified. 1

General Treatment Principles

• Helminth infections (worms) are the most common cause of parasitic eosinophilia, while protozoan infections rarely cause significant eosinophilia 2
• Treatment selection depends on identifying the specific parasite through appropriate diagnostic testing including stool microscopy, serology, and travel history 1
• For empirical treatment of asymptomatic eosinophilia with negative diagnostic workup, a combination of albendazole 400 mg single dose plus ivermectin 200 μg/kg single dose can be considered 1
• Always exclude Loa loa infection before administering ivermectin in patients who have traveled to endemic regions, as severe reactions can occur 1
• Monitor for potential side effects of antiparasitic medications, particularly bone marrow suppression with albendazole 3

Treatment by Specific Parasites

Intestinal/Tissue Nematodes

• Strongyloidiasis: Ivermectin 200 μg/kg daily for 2 days is the treatment of choice 1, 4

  • For hyperinfection syndrome in immunocompromised patients, extended treatment and specialist consultation is required 1
  • Albendazole 400 mg twice daily for 7 days is an alternative but less effective 1

• Ascariasis: Albendazole 400 mg as a single dose 1

  • Alternative: Mebendazole 500 mg as a single dose 1

• Hookworm infections: Albendazole 400 mg as a single dose 1

  • Alternative: Mebendazole 500 mg as a single dose 1

• Toxocariasis (Visceral larva migrans): Albendazole 400 mg twice daily for 5 days 1

  • For ocular or CNS involvement, add corticosteroids 1

• Trichinellosis: Albendazole 400 mg daily for 3 days in mild disease; longer courses for severe disease 1

  • Add corticosteroids for severe inflammatory reactions 1

Trematodes (Flukes)

• Schistosomiasis: Praziquantel 40 mg/kg in two divided doses for 1 day 1

  • For acute schistosomiasis (Katayama syndrome) with neurological symptoms, start with corticosteroids alone before adding praziquantel 1
  • For neuroschistosomiasis: Praziquantel 40 mg/kg twice daily for 5 days plus dexamethasone 4 mg four times daily, tapering over 2-6 weeks 1

• Liver flukes (Clonorchis, Opisthorchis): Praziquantel 25 mg/kg three times daily for 2-3 days 1

• Paragonimiasis: Praziquantel 25 mg/kg three times daily for 2 days 1

  • Can cause extremely high eosinophilia (>80%) with elevated IL-5 levels 5

Cestodes (Tapeworms)

• Taenia saginata/T. solium: Praziquantel 10 mg/kg as a single dose 1

  • For neurocysticercosis: Albendazole plus corticosteroids, with specialist consultation 1

• Hymenolepis nana: Praziquantel 25 mg/kg as a single dose 1

• Echinococcosis: Complex management requiring specialist consultation 1

  • Albendazole 400 mg twice daily for prolonged periods, sometimes with praziquantel 1
  • Surgical or percutaneous interventions may be necessary 1

Filarial Infections

• Onchocerciasis: Ivermectin 200 μg/kg monthly for 3 months, then every 3-6 months until asymptomatic 1

  • Add doxycycline 200 mg daily for 6 weeks to target symbiotic Wolbachia bacteria 1

• Lymphatic filariasis: Diethylcarbamazine (DEC) with specialist advice 1

  • Exclude co-existing onchocerciasis before using DEC 1

Special Considerations

• Pregnancy: Many antiparasitic medications are contraindicated; albendazole may cause fetal harm 3
• Immunocompromised patients: Higher risk of disseminated disease, particularly with strongyloidiasis; may require longer treatment courses 1
• CNS involvement: Add corticosteroids to prevent inflammatory reactions when treating neurocysticercosis or neuroschistosomiasis 1, 3
• Liver disease: Patients require more frequent monitoring of blood counts when on albendazole due to increased risk of bone marrow suppression 3

Monitoring and Follow-up

• Monitor blood counts at the beginning of treatment and every 2 weeks while on albendazole therapy 3
• Monitor liver enzymes before starting treatment and at least every 2 weeks during albendazole treatment 3
• Consider repeat stool examinations or serology to confirm parasite clearance 6
• Eosinophil counts typically normalize rapidly after effective treatment, confirming treatment efficacy 2