Protazoa Flashcards
Entamoeba histolytica disease
amebiasis: bloody diarrhea, RUQ pain
immunocomp’d: liver abcess, lung, brain- systemic dissemination
trophozoites attach and invade intestinal mucosa forming “flask-shaped” lesions
incubation= 10-12 days
Entamoeba histolytica transmission/diagnosis
transmitted: infectious cysts in water
diagnosed by detecting trophs/cysts in stool on 3 consecutive days
Entamoeba histolytica histo
trophozoite: gound glass cytoplasm with single nucleus, RBCs as inclusion bodies
Cysts: spherical with 1-4 nuclei and sausage shaped chromatoid bodies
Acanthamoeba
Non-GI ameoba free-living protazians immunocomp'd: pneumonitis, dermal ulcerations, fatal encephalitis healthy: ulcerative keratitis CONTACT LENSES
Naegleria fowleri
free living ameoba in warm fresh water
enters brain via olfactory route–> primary amebic meningoencephalitis- 7 days fatal
giardia lamblia disease
Giardiasis: bloating, flatulence, foul-smelling, fatty diarrhea
infective cysts in mountain spring water
trophozoites cover villi of small intestine and interfere with absorption of fat and fat soluble vitamins
NO INVASION=NO BLOOD
giardia lamblia diagnosis
2-3 week incubation, detect trophozoites or cysts in stool “string test”
giardia lamblia histo/morph
troph: pear-shaped with sucking disk, 2 nuclei and 4 pairs of flagella
cyst is a football shaped with 2-4 nuclei
trichomonas vaginalis disease
GU Flagellate
no cyst stage, transmitted by sexual contact and or contaminated towels
symptoms only in women: vaginal irritation, burning, purulent discharge
trichomonas vaginalis histo/morph
one nucleus, oval-pear shaped
motile with 4 flagella
microscopic detection of trophozoites in vaginal secretions
Cryptosporidium disease
mild watery diarrhea in non-immunocompromised
SEVERE DISEASE IN AIDS
Cryptosporidium epi/morph
infective cysts in water, resistant to chlorination of water, waterborne outbreaks known
acid fast intracellular organism
cyclospora cayetanensis
larger than cyrptosporidium
acid fast oocysts
contaminated fruit, SA (raspberries)
DIARRHEA
Isospora belli
MAJOR PROBLEM IN AIDS PT’s
diagnostic is large oval oocyst, with 2 embryos
acid fast
balantidum coli
CILIATE, causes bloody diarrhea, does not invade beyond gut wall though, cyst is diagnostic and infectious
