primary amebic meningoencephalitis
(PAM) a rare, acute, often fatal type of meningoencephalitis caused by infection with the usually free-living soil and water ameba Naegleria fowleri. It is characterized by suppuration and fever and is most often seen in young persons who have bathed in contaminated fresh water. Pathogens gain access to the central nervous system through the nasal mucosa and cribriform plate and then follow the olfactory bulbs and nerves to the brain and meninges. Similar but more subacute or chronic infections by species of Acanthamoeba and Balamuthia are called granulomatous amebic encephalitis.
Medical dictionary.
2011.