Rapid therapeutic response of eosinophilic meningoencephalitis in a toddler with Baylisascaris procyonis infection

Introduction: Eosinophilic meningitis is an infrequently encountered condition. Baylisascaris procyonis (raccoon roundworm) infection, rarely diagnosed in North America, is a known cause of eosinophilic meningitis, often producing death or permanent neurologic damage. Case Report: We recently encountered a toddler with geophagia and probable exposure to raccoon feces, who presented with eosinophilic meningitis and encephalitis, and was diagnosed with B procyonis infection and possible Toxocara co-infection. His marked peripheral eosinophilia and neurologic symptoms rapidly responded to corticosteroid and albendazole therapy. Discussion: Since B procyonis infection is infrequently encountered, its diagnosis in the proper clinical and epidemiologic setting may not always be considered, resulting in a delay of appropriate therapy. Our patient, diagnosed and treated early in his course, demonstrated rapid clinical and laboratory improvement with anti-inflammatory and antiparasitic therapy. Conclusion: In cases of eosinophilic meningitis, infection with B procyonis should be routinely considered to allow timely institution of effective therapy for this unusual but potentially fatal or debilitating infection.