Amebae and Balantidium Flashcards
deaths from Amebiasis are highest in ____, people of ___ & ____ descent, and people who are age ____ or above
males, Hispanic, Asian/Pacific Islander, 75
deaths from Amebiasis are associated with ____ infection
HIV
more than 40% of fatal amebiasis occur in which states?
CA & TX
where is Entamoeba histolytica found?
distributed all over the world
what is the reservoir for Entamoeba histolytica?
humans
true or false: many protozoan species in the genus Entamoeba colonize humans, but NOT all are associated with disease
true
E. histolytica is pathogenic as it gobbles up ___, but E. _____ is noninvasive, but is morphologically _______ from E. histolytica
RBCs, dispar, indistinguishable
describe the lifecycle of E. histolytica
an individual who is infected will shed cysts and trophozoites. the trophozoites will not survive, but the cysts are hardy and can survive in the environment for days-weeks, until they’re ingested by a human. once inside a human, the cyst transforms into trophozoites.
name symptoms that fall under “invasive intestinal amebiasis”
- dysentery, ulceration/inflammation of colon
- appendicitis
- toxic megacolon
- amebomas (granuloma that forms around the amoeba)
name symptoms that fall under “invasive extraintestinal amebiasis”
- liver abscess
- pleuropulmonary abscess
- cutaneous and genital amebic lesions
- brain hemorrhages (bleeding)
the content from amebic abscess have a ______ color
chocolate
skin infections from E. histolytica can be intense in the _____ region, because the _____ are excreted and can divide in the surrounding tissue
perianal, trophozoites
how to diagnose amebiasis?
- first try to see the parasites
- rule out with 3x stool exam
- fresh stool wet mount & permanent stain
- biopsy
- liver scan, CT scan, ultrasound
a modern way to diagnose E. histolytica?
PCR (E. histolytica is on the multiplex PCR panel)
size of E. histo/dispar trophozoite?
15-20 microns (15-60 range)
appearance of E. histo/dispar trophozoite?
single nucleus w/ central karyosome, peripheral chromatin
erythrophagocytosis is a clue for E. ____
histolytica
what is the appearance of the cytoplasm of E. histo/dispar trophozoites?
ground glass cytoplasm
E. histo/dispar trophozoites are typically found in _____ stool, while the cyst forms are usually found in ______ stool
diarrheal, formed
how many nuclei are in the cysts of E. histo/dispar?
4 nuclei
what else does the cyst of E. histo/dispar contain?
chromatoidal body
for E. histo/dispar, 1 cyst gives rise to __ trophozoites
4
the chromatid body for E. histo/dispar has _____ ends
rounded
if you see 5, 6, or more nuclei then it is NOT E. ______
histoytica
if you can’t visually see the parasite, use _____ or ____ assays
immuno/molecular
immunoassays include fecal antigen ____
EIA
serology can be useful in ______ disease, but not for ______ disease
extraintestinal, intestinal
serology is ____ sensitive for EI disease, ___ sensitive for intestinal, and ___ for asymptomatic carriers
95%, 70%, 10%
serology (antibody EIA) cannot differentiate between __ vs. ___ infections
new vs. past (maybe look for IgM)
E. dispar is __ times more frequency that E. histolytica
10x
true or false: E. histo and dispar can be distuingished by immunologic, molecular assays (PCR), or isoenzymatic assays, but also erythrophagocytosis
true
Entamoeba coli (E. coli) can be distinguished by E. histolytica because its cyst form has _____ nuclei
8+
Entamoeba coli also has an ____ shaped karyosome
unusually
the cysts for E. coli are 10-___ microns
35
the trophozoite form of E. coli looks different from E. histo because it has a ____ and ____ karyosome. its cytoplasm also appears as ____
unusual, large, dirty
size of E. coli trophozoite?
15-50 microns
Entamoeba hartmanni is like a ___ version of E. histolytica
mini
while E. histo trophozoites are 15-20 (15-60 range) microns, E. hartmanni trophozoites are _____ microns
5-15
while E. histo cysts are 10-20 microns, E. hartmanni cysts are ____
5-10
the cyst of Endolimax nana is different because although it has __ nuclei, it lacks _____ bodies
chromatin
the trophozoite form of Endolimax nana has a large _______, and it is smaller than E. histo (6-12 microns)
karyosome
Iodamoeba buetschlii is different because its cyst has a ______ _____. the trophozoite form is sluggish and has a _____ central karyosome
glycogen vacuole, large
true or false: dientamoeba fragilis is actually not an ameba, but is a flagellate
true
Dientamoeba has no ____ stage
cyst
Dientamoeba trophozoites have __ nuclei
2
Entamoeba polecki’s cyst form has several _____ _____ with _____ ends
chromatoid bodies
pointed
for prevention of amebiasis, handwashing should be practiced, as with washing fruits/veggies with ______
detergents
amebiasis may possibly be transmitted via _____ contact, where if there are ____ lesions involved, they could spread
sexual, perianal
water treatment for prevention of amebiasis?
boiling, iodination (chlorination does not work)
treatment for symptomatic amebiasis?
metronidazole
treatment for asymptomatic amebiasis?
iodoquinol, paromomycin, diloxanide furoate (not available in US)
Balantidium is unique because it is the ONLY _______ parasite known to infect humans. The reservoir is ____. It does invade the __ _____ but it does not typically go beyond that.
ciliated
pigs
GI tract
similar to E. histo, balantidium parasites are excreted as ____ and _____, but the ______ does not survive
trophozoites, cysts, trophozoites
the balatidium ___ is infectious and can contaminate food and water, then it becomes ingested by a human and the cyst forms _____. some of the trophozoites invade the ____ of the colon.
cyst, trophozoites, wall
balantidium’s nucleus is ____-shaped
bean
the balantidium trophozoite is considerably large. it is between __ and ___ microns.
40-200
the balantidium trophozoites also have a _____. this is where nutrients come in.
cystome
balantidium can form _____ ulcers
colonic
