Intestinal protazoa Flashcards
Entamoeba histolytica
Sarconida spread via fecal-oral no mito DNA phago bacterial and RBCs form amebapore via hydrolysis
E. histolytica life cycle
trophozoite –> pathogenic stage; large intestine
cyst –> infectious stage; small intestine
8 tropho : 1 cyst
can withstand head and Cl- in water supply, and stomach acid
adhere via galactose and NaG lectins
E. histolytica patho
diarrhea, farting, cramps acute inflammatory resp may prod hepatic abscesses w/o inflame response can also see chest inf look for organ in wet mounts
Giardia lamblia
binucleated flagellate (4 pairs of flagella)
has sucker for attachment
no mito DNA
grow anaerobically
poor hygiene / daycare centers / crowded conditions
hikers drinking bad water
G. lamblia life cycle
trophozoite –> small intestine; multiplicative form
cyst –> large intestine; has GalNac polymer
sec proteases to degrade mucosal layer of small intestine
G. lamblia patho
acute --> EXPLOSIVE diarrhea greasy, foul smelling stools LOTS OF GAS no blood or mucus chronic --> carrier state malabsorption of B12, fats, and CHO
Cryptosporidium
obligatory intracellular parasite swimming pool illness; resistant to Cl- explosive, profuse watery diarrhea severe fluid loss, wasting and death in compromised boil water
Cryptosporidium life cycle
oocysts –> infectious forms
capable of auto infection
Cyclospora cayetanensis
hard to distinguish from Cryptosporidium
will have larger oocysts in stools
is treatable, unlike Crypto
Enterocytozoon bieneusi
microsporidiosis obligate intracellular protozoan polar tubules that coil inside the spore diarrhea acalculous cholecystitis
Encephalitozoon intestinalis
microsporidiosis obligate intracellular protozoan polar tubules that coil inside the spore diarrhea can disseminate to ocular, GU or resp tracts
Balantidium coli
large parasitic ciliate sometimes confused with E. histolytic Res: PIGS cysts = infectious persistent diarrhea; sometimes dysentery tx, with tetracycline
