What is the most common cause of chronic diarrhea in travelers?
Giardiasis
What is the leading cause of death from parasite worldwide?
Entamoeba histolytica
Which is the most common cause of recreational water-related disease outbreak in the US?
Cryptosporidiosis
Cellularity of protozoa?
Unicellular eukaryotes
How do protozoans reproduce?
By binary fission
Where do Trophozoites replicate?
Inside of us
True/false: trophozoites are the infective stage and they replicate in the outside environment
False; they are not the infective stage and they replicate inside of us
True/false: trophozoites have cytoplasmic membrane in its outermost layer
True
When do trophozites encyst?
They become cysts (encyst) as they move down to the colon
True/false: Cysts are non mobile and do not replicate
True. They are usually passed in feces
When do cysts excyst?
They excyst in small intestines and become trophozoites
Which part of the fecal-oral life cycle does the protozoa feed, move and replicate? Which part of the life cycle is it passed in the feces, resistant and infective form.
Trophozoite- feeding, motile, replicate
Cyst- passed in feces, nonmotile, resistant and infective
Which of the intestinal protozoan is it an obligate intracellular parasite?
Cryptosporidium
Which of the intestinal protozoan has flagella?
Giardia duodenalis
Which of the intestinal protozoan is an ameba?
Entamoeba histolytica
Cholera-like (mild to fulminant) diarrhea is seen in______
Cryptosporidiosis (esp in immunocompromised)
Bloody, mucousy diarrhea, flask shaped ulcers and liver abscesses is seen in_____
Amebiasis
Greasy and fatty, foul-smelling and watery diarrhea is seen in ______
Giardiasis
True/false: benefits of diarrhea in host and the microbe is essentially the same
True; get the microbes out so it can spread
What is the predominant cause of travelers diarrhea?
E coli
How are protozoans transmitted?
Cysts
True/false: protozoans can be transmitted through anal-oral sex
True
Cysts excyst in ______, to become ________. Trophozoites encyst in _______, to become _______.
Small intestine; trophozoite (replicating form)
Colon; cysts (infective form)
How are protozoans diagnosed?
microscopic analysis of cysts in stool
ELISA (fecal immunoassays)
Which intestinal protozoans have shared reservoirs in mammals, fish, amphibians, reptiles, birds?
Giardia
Cryptosporidium
True/false: Entamoeba has reservoir in fish, amphibians, reptile and birds
False; they have a human reservoir. The other two have the common shared reservoris in fish, amphibian, reptile and birds etc.
Which intestinal protozoan has disease stage that penetrate human colon with a secondary infection of liver?
Entamoeba histolytica
Which intestinal protozoan has disease stage in duodenum/ jejunum?
Giardia
Which intestinal protozoan has disease stage that multiply intracellularly in mucosal epithelial cells in the small intestines?
Cryptosporidium
Which one ingests RBC, bacteria as their virulence factor?
Entamoeba histolytica
Which one has pore-forming protein cytotoxin and proteases?
Entamoeba histolytica
True/false: having a lot of diarrhea can sometimes lead to passing of trophozoites
True; these trophozoites do not survive in the environment
Which is the most common extracolonic site for Entamoeba trophozoites to invade?
Liver
True/false: Entamoeba trophozoites penetrate areas with least motility
True
True/false: there are commensal Entamoeba, but ELISA is able to distinguish between commensal ones and diarrheal ones
True
Anchovy paste is seen in surgical drainage of _____
Entamoeba
Little man (aka heart or tear- shaped) shaped trophozoite is indicative of ______
Giardia duodenalis
True/false: Giardia trophozoite is binucleate and flagellated. While the cyst is 4-nucleate
True
Which intestinal protozoa has a large ventral sucker used for attachment to intestinal villi?
Giardia duodenalis
Chronic infection of which organism can lead to malabsorption?
Giardia duodenalis, because of the large sucker that attaches to the intestinal villi causing malabsorption
Cryptosporidium can too
Which organism can cause chronic, life-threatening illness in immunocompromised/ AIDS patients?
Cryptosporidium
Where do cryptosporidium replicate?
they replicate inside the cells and killing the cells that way.
True/false: cryptosporidiosis in non immunocompromised patient is self-limiting, while in immunocompromised patients it can cause fulminant cholera like watery diarrhea
True
Which intestinal protozoan has acid-fast (pink/red) oocysts in fresh stool samples?
Cryptosporidium
Migratory parasite like Entamoeba can cause _____
Eosinophilia
True/false: you cannot see trophs of cryptosporidium in stool because they are too tiny
True. Whereas you may be able to see trophs of giardia because they are larger
