Fatal Eosinophilic Meningoencephalitis and Visceral Larva Migrans Caused by the Raccoon Ascarid Baylisascaris procyonis

VISCERAL larva migrans is a subacute inflammatory disease characterized by hepatomegaly, eosinophilia, and hypergammaglobulinemia and due to the larval migration in human beings of nematodes normally parasitic in lower animals.1,2 Most cases in the United States occur in young children and are caused by the dog ascarid Toxocara canis3 A fatal outcome and central nervous system involvement are rare.3 Ingestion of soil contaminated by infective eggs is the usual mode of acquisition. A specific parasite can be identified with certainty, however, only by morphometric analysis of larvae in tissue specimens, so the recent development of serodiagnostic tests for T…