What is the treatment and diagnostic approach for patients exposed to worms by dogs?

Treatment and Diagnostic Approach for Patients Exposed to Worms by Dogs

For patients exposed to worms by dogs, the recommended treatment is albendazole 400 mg daily for 3-5 days or ivermectin 200 μg/kg as a single dose, depending on the specific parasite identified. 1

Diagnostic Approach

• Stool examination: Concentrated stool microscopy is the first-line diagnostic test for confirming intestinal helminth infections. For pinworm infections, the "sellotape test" (placing sticky tape on perianal skin and examining under microscope) is recommended 1
• Serology: For suspected visceral larva migrans (Toxocara), serology is the preferred diagnostic method 1
• Skin examination: For cutaneous larva migrans, diagnosis is typically clinical based on the characteristic serpiginous, itchy rash 1
• Eosinophil count: Elevated eosinophil count (eosinophilia) is common with helminth infections and should prompt investigation 1

Common Dog-Associated Worm Infections and Treatment

1. Cutaneous Larva Migrans (Dog/Cat Hookworm - Ancylostoma braziliense, A. caninum)

• Clinical presentation: Characteristic self-limiting itchy, serpiginous rash migrating at 1–2 cm per day 1
• Treatment options:
  • Ivermectin 200 μg/kg orally as a single dose (preferred) 1, 2
  • OR Albendazole 400 mg orally once daily for 3 days 1

2. Visceral Larva Migrans/Toxocariasis (Toxocara canis, T. cati)

• Clinical presentation: Fever, eosinophilia, dyspnea, wheeze, cough, abdominal pain, hepatosplenomegaly, and urticarial rash 1
• Treatment:
  • For mild-moderate disease: Albendazole 400 mg twice daily for 5 days 1
  • For severe disease: Albendazole 400 mg twice daily for 5 days plus prednisolone 40-60 mg daily 1
  • For ocular disease: Requires joint care with ophthalmology - albendazole 400 mg twice daily for 2-14 days (depending on severity) plus corticosteroids 1

3. Intestinal Worms (Various species)

• Treatment for common intestinal worms:
  • Albendazole 400 mg as a single dose 3, 4
  • OR Mebendazole 100 mg as a single dose for pinworms 1

Prevention Strategies

• Hand hygiene: Thorough handwashing after contact with dogs or soil potentially contaminated with dog feces 1, 5
• Environmental management:
  • Regular removal of pet feces to reduce environmental contamination 5
  • Minimize children's exposure to potentially contaminated environments 5
• Regular deworming of pets: Particularly puppies, pregnant and nursing animals, and hunting dogs which pose highest risk 5
• Education: Pet owners should be educated about zoonotic risks and prevention measures 5

Special Considerations

• Immunocompromised patients: May require more aggressive treatment and monitoring 1
• Pregnant women: Albendazole should ideally be avoided during pregnancy, especially first trimester 1
• Children: Dosing should be adjusted by weight; children <5 years are at higher risk for toxocariasis 1
• Severe infections: May require hospitalization, especially with complications like intestinal or biliary obstruction 1

Common Pitfalls to Avoid

• Misdiagnosis: Symptoms of worm infections may mimic other conditions - eosinophilia is an important clue 1
• Inadequate treatment duration: Some infections require longer treatment courses than others 1
• Neglecting household contacts: Family members and close contacts may need screening and treatment 1
• Overlooking environmental contamination: Dog worm eggs can persist in soil for months to years 5
• Underestimating zoonotic potential: Even well-cared-for pets can transmit parasites 1, 5