Amoeba & Ciliates Flashcards
what are amoeba?
protozoa, infects wide variety of species (inc. humans)
what type of parasites are amoeba?
facultative
aka do NOT require host to live, just feed
what are the most important amoeba in vet med?
Entramoeba histolytica
Entramoeba invadens
Ancanthamoeba spp
Naegleria fowleri
Entramoeba histolytica affect which species?
dogs, cats, humans
Entramoeba invadens affects which species?
reptiles
Acanthamoeba spp affect which species?
humans, can rarely affect vet species
Naegleria fowleri affects which species?
humans, primates, cattle
describe the cyst stage of amoeba
round
non-motile
environmentally resistant
describe the trophozoite stage of amoeba
amoeboid
motile
feeding/pathogenic stage!!!
what are the two life stages of amoeba?
trophozoites
cysts
can amoeba cysts be infectious?
yes, if ingested
amoeba routes of infection
fecal-oral
nasal mucosa (inhaled)
eye
skin abrasions
what parts of the body can amoeba effect?
intestinal, extraintestinal, liver, lung, brain
which nerve allows movement of amoeba to the brain?
olfactory nerve
list the mechanisms of amoebic infection pathogenesis?
malabsorption
direct tissue destruction
incite inflammatory response
ID the life stage of Entamoeba histolytica
cyst
ID the red and yellow circles. which amoeba life stage and species is it?
cyst of Entamoeba histolytica
red = 4 nuclei
yellow = blunt chromatoidal bar
ID the life stage of Entamoeba histolytica amoeba
trophozoite
ID the red and blue circles. which amoeba life stage and species is it?
red = 1 nucleus
blue = central karyosome
Entamoeba histolytica
what is a karyosome?
endosome in the trophozoite of Entamoeba histolytica
Entamoeba histolytica is morphologically indistinguishable from ___
Entamoeba invadens
who is Entamoeba invdens NOT transmissible to?
mammals
does Entamoeba invadens have reservoir hosts?
yes
some reptiles are resistant
which reptiles are most susceptible to Entamoeba invadens?
boas, colubrids, vipers, crotalids
which amoeba is this?
Entamoeba invadens
intestinal
Transmural necrohemorrhagic enterocolitis
what are clinical signs of Entamoeba invadens?
anorexia, V, mucoid/hemorrhagic D, sudden death
Loss of ___ predisposes reptiles with Entamoeba invadens to sepsis
intestinal barrier
what type of Entamoeba invadens is this?
intestinal
Transmural necrohemorrhagic colitis
describe Entamoeba invadens enterocolitis
subsequent hepatitis following hematogenous dissemination via portal vein
which life stage of Acanthamoeba is this?
trophozoite
which life stage of Acanthamoeba is this?
cyst
ID the arrows in a Acanthamoeba trophozoite
ID the arrows in a Acanthamoeba cyst
what’s the main transmission mode of Naegleria fowleri?
inhalation
can you get infected by swallowing water contaminated with Naegleria?
NO
ID the issue caused by Naegleria fowleri
primary amoebic meningocephalitis (PAM)
what’s the drug of choice for amoeba?
Metronidazole
inhibits DNA synthesis
NOT in food animals
what are ciliates?
has TWO life stages (trophozoite and cyst)
cilia are all around
dimorphic nucleus
macronucleus
>1 micronuclei
what type of parasite are cilia?
commensal
rarely cause disease
is this amoeba or ciliate?
ciliate
Answer the following
