SKIN, EYE and CNS PARASITES
LOBOSEA Order: Amoebida

ACANTHAMOEBA SP.

aca1-ic

Acanthamoeba spp.: free living amoebae of the Acanthamoeba genus
cause two clinical syndrome:
1) Granulomatous amoebic encephalitis (GAE)
2) Subacute and chronic amoebic keratitis
A disseminated form of GAE is described in individuals with the Acquired
Immunodeficiency Syndrome (AIDS)
Several species of Acanthamoeba have been identified:
A.castellani, A.culberstoni, A.polyphaga, A.zhysodes, A.hatchetti, 
A.astronyxis, A.palestinensis.
(Trophozoites, trichrome stain).

aca2-ic

Acanthamoeba spp.: clinical manifestations include chronic
granulomatous encephalitis and keratitis
(in particular in individuals who wear contact lens); some case of disseminated
cutaneous infection have been reported in AIDS patients.

aca3.ic

Acanthamoeba spp.: the trophozoite is irregular, 15-45 µm,
having micropseudopodia called acanthopodia;
in trichrome stain the cytoplasm of trophozoites appears greenish pink,
the central located kariosome pink or red.
(Trichrome stain).

aca4.ic

Acanthamoeba spp.: the cysts are spherical, 15-20 µm in diameter,
having a thick double wall. The outer wall may be spherical or wrinkled,
the inner wall appear stellate or polyhedral.
(Acanthamoeba trophozoites and a cyst, trichrome stain).

aca5.ic

Acanthamoeba spp.: both forms have a single nucleus with a large
centrally located nucleolus. With trichrome stain, the cysts stain red.
Species identification is based on morphology of cysts (stellate, polyhedral). 

38saygi.ic

Acanthamoeba spp.: trophozoite as seen under phase contrast microscope. 
Its big nucleolus, both lobopodia and acanthopodia 
and various vacuoles can be seen clearly.

40saygi.ic

Acanthamoeba spp.: trophozoites as seen 
under phase contrast microscope.

43saygi.ic

Acanthamoeba spp.: cysts stained with 
Heidenhain’s iron alum-haematoxylin method.


 

Feed_tracts_4x	Feed_tracts_10x

Trophozoites_400X	A_castellani_ 1000X

Acanthamoeba spp.: Acanthamoeba may be cultured on non nutrient
agar flooded with Page's saline solution and overlaid with Escherichiacoli.
"Feed" tracks on agar plate (Feed_tracts_4x ; Feed_tracts_10x ). 

Trophozoites on agar plate (Trophozoites_400X); trophozoite of
Acanthamoeba castellani  (A_castellani_1000X).

 
 
 


SKIN....   EYE.... CNS....