Primary amebic meningoencephalitis diagnosed in the emergency department.

Reported is a case of primary amebic meningoencephalitis diagnosed in the emergency department. The patient, a previously healthy teenager, developed Naegleria meningoencephalitis after swimming in a freshwater public pool. The Naegleria caused acute fulminating infection culminating in the death of the patient 36 hours after admission. Results of a spinal tap, together with the history of swimming in warm fresh water, led to the emergency department diagnosis.