Diarr Protozoans (lec 7) Flashcards
Giardia lamblia microbe characteristics?
flagellate protoza
G. lamblia morphology stages? (2)
1) Trophozoite:
In SI, eats mucus, Ø tissue invasion
2) Cyst:
In environment, makes 2 trophozoite, 4 nuclei when mature
G. lamblia Life Cycle? (4 steps)
1) Ingestion (infection)
2) Excystation in stomach
3) Replicate in SI bile salt and neutral pH
4) Cysts -> poop
G. lamblia sxs?
aysmp to acute/chronic D
G. lamblia action?
causes malabsorption
G. lamblia epidemiology?
highly contagious,
contaminated H2O,
(U) kids,
travel, camp, oral
G. lamblia diagnostics? (2)
Stool sample
ELISA for GSA65 antigen
G. lamblia tx?
DOC: metronidazole
Human milk has IgA against,
Develop post-exposure Ab
Amebiasis/
E. histolytica morph stages?
1) Trophozoite:
invasive/pathogenic/motile
pseudopod-forming
2) Cyst:
infectious stage
E. histolytica sxs?
Widespread (intestinal/extraintest)
asymp to colitis, abscess, ulcers
(U) bloody D
E. histolytica epidemiology?
Fecal H2O
reportable
kids, compromised
E. histolytica Life Cycle?
1) Ingest cysts
2) Excystation in Colon
3) Trophoz colonize colon mucus
4) Encyst -> poop or disseminate to blood
E. histolytica diagnostics?
stool sample
ELISA
radiology for extraintest
E. histolytica tx?
DOC: metronidazole + iodoquinol
Must boil H2O -> resistant to Cl-
E. histolytica virulence factors? (4)
1) Lectin: adhesion
2) Phospholipases: disrupt host membrane
3) Amebapore: makes channels in host (lysis)
4) Cysteine Proteases: degrade mucus, Ab, complement, cell matrix