Visceral larva migrans

Background

Organism	Host	Notes
Toxocara canis	canines	most common cause in humans
Toxocara cati	felines
Baylisascaris procyonis	raccoons

• Humans are dead-end hosts

Clinical Manifestations

• Most frequently in young children (who are effective at getting dirt into their mouths)
  • Mean age 2 to 4 years
• Most infection is asymptomatic
• Severe symptoms eosinophilia, fever, and hepatomegaly
• Other common symptoms include cough, wheezing
• Rarely, urticaria and nodules
• Very rarely, ocular involvement

Different Diagnosis

• Other parasites
  • Baylisascaris procyonis
  • Acute schistosomiasis
  • Fasciola hepatica, Clonorchis sinensis, and Opisthorchis viverrini
  • Ascaris lumbricoides liver abscess
  • Echinococcus
  • Capillaria hepatica
• Other diseases

Diagnosis

• Mostly clinical ± serology
• May be able to see larvae on tissue histopathology

Management

• For mild or moderate disease, clinical monitoring is all that is needed as it self-resolves in most cases
• For severe or life-threatening disease, can try treating with albendazole, mebendazole, diethylcarbamazine
  • Adjunctive corticosteroids are used due to intense inflammatory reaction to dying parasites

Prevention

• Do not eat dog, cat, or raccoon poop
• Keep sandboxes closed when not in use, and keep pets away from them
• Test and treat dogs regularly