Acanthamoeba

Acanthamoeba

 [ah-kan″thah-me´bah]

a genus of free-living ameboid protozoa found usually in fresh water or moist soil. Certain species, such as A. castella´ni, A. poly´phaga, A. astronyx´is, and A. culbert´soni, may occur as opportunistic human pathogens, causing an acute fatal or chronic infection of the eye, brain, liver, kidney, lung, pancreas, and skin in patients with underlying disease or in immunocompromised patients.

Acanthamoeba

(ă-kan'thă-mē'bă),

A genus of free-living ameba (family Acanthamoebidae, order Amoebida) found in and characterized by the presence of acanthopodia. Human infection includes invasion of skin or colonization following injury, corneal invasion and colonization, and possibly lung or genitourinary tract colonization; a few cases of brain or central nervous system invasion have occurred, but not solely by the olfactory epithelium route of entry as with the more virulent infections caused by Naegleria fowleri. Species responsible are chiefly Acanthamoeba culbertsoni, but cases have been reported involving Acanthamoeba castellanii, Acanthamoeba polyphaga, and Acanthamoeba astronyxis. Most cases have been chronic rather than fulminating and rapidly fatal as with N. fowleri infection.

[G. akantha, thorn, spine, + Mod. L. amoeba, fr. G. amoibē, change]

Acanthamoeba

A genus of free-living pathogenic amoebae, which are ubiquitous in the environment, the cycle of which consists of 2 stages: a trophozoite (which is 14–40 µm in diameter) and a cyst (which has a double-layered wall with a diameter of 12–16 µm).

Sources
Tap water, dust, soil, sewage, air-conditioning units.
 
Diseases caused by:
Amoebic keratitis, acanthamoeba granulomatous encephalitis.

Acanthamoeba

A genus of free-living pathogenic amoebas Sources tap water, dust, soil, sewage, air conditioning units. See Acanthamebiasis. Cf Leptomyxid, Naegleria.