A case report of Coccidioides posadasii meningoencephalitis in an immunocompetent host

Coccidioides spp. are dimorphic fungi endemic to Central America, regions of South America and southwestern USA. Two species cause most human disease: Coccidioides immitis (primarily California isolates) and Coccidioides posadasii. Coccidioidomycosis is typically acquired through inhalation of soil or dust containing spores. Coccidioidal meningitis (CM), most common in the immunocompromised host, can also affect immunocompetent hosts.

We report a case of C. posadasii meningoencephalitis in a previously healthy 42-year-old Caucasian male who returned to Canada after spending time working in New Mexico. He presented with a 3-week history of headache, malaise and low-grade fevers. He developed progressive confusion and decreasing level of consciousness following hospitalization. Evidence of hydrocephalus and leptomeningeal enhancement was demonstrated on magnetic resonance imaging (MRI) of his brain. Serologic and PCR testing of the patient's CSF confirmed Coccidioides posadasii. Despite appropriate antifungal therapy he continues to have significant short-term memory deficits and has not returned to his full baseline functional status.

Travel to endemic regions can result in disease secondary to Coccidioides spp. and requires physicians in non-endemic areas to have a high index of suspicion. Effective therapeutic options have reduced the mortality rate of CM, however, it is still associated with significant morbidity and requires life-long therapy.