infectious diseases
Primary Amebic Meningoencephalitis
Diagnosis
Cerebrospinal fluid examination Primary amebic meningoencephalitis is suspected based on history of swimming in fresh water, but confirmation is difficult because CT and routine cerebrospinal fluid (CSF) tests, although necessary to exclude other causes, are nonspecific. Wet mount of fresh, not refrigerated or frozen, CSF should be done; it may demonstrate motile amebic trophozoites (which can be seen in Giemsa-stained specimens but are destroyed by Gram stain techniques). Immunohistochemistry, amebic culture, polymerase chain reaction of CSF, and/or brain biopsy are available in specialized reference laboratories. Consultation with the Centers for Disease Control and Prevention (CDC) or other experts in the diagnosis of amebic encephalitis is recommended. 