Protozoa Flashcards
Describe the life cycle of malaria?
Mosquito injects sporozoite into skin
Sporozoites go to the liver
Exoerythrocytic cycle: sporozoites–>early schizont–>late schizont–>merozoites rupture the hepatocyte and go into the bloodstream and attach to RBCs.
Erythrocytic cycle: Trophozoite (looks like engagement ring)–>early schizont–>late schizont–>merozoites that rupture.
Get gametocytes that go back into mosquito
Which conditions can be treated with metronidazole?
GET GAP on the Metro giardia entamoeba trichomonas gardnerella anaerobic bacteria H. Pylori
How do you treat malaria?
chloroquine (heme polymerase inhibitor)
latent phase–primaquine
resistant malaria: quinine + doxycycline
What is the most common protozoal diarrhea?
giardia
What are the important things to know about giardia?
campers drink water w/ giardia
causes fatty diarrhea, flatulence, bloating
Owl body b/c 2 nuclei
can see trophozoites in stool
treat w/ metronidazole
What are the important things to know about entamoeba histolytica?
causes amebiasis
bloody diarrhea
liver abscess-anchovy paste, flask-shaped ulcer, RUQ pain
have multiple nuclei
What are the important things to know about cryptosporidium?
causes severe diarrhea
oocysts that are acid fast
nitazoxanide used to treat
What causes bacterial dysentery? What causes bloody diarrhea protozoal?
bacterial dysentery: shigella
protozoal dysentery: entamoeba histolytica
Cryptococcus causes what? Cryptosporidium causes what?
cryptococcus–meningitis
cryptosporidium–severe diarrhea
What are the important things to know about toxoplasma gondii?
AIDS: ring-enhancing lesion
found in meat, cat feces, crosses placenta
congenital toxoplasmosis
What are the features of congenital toxoplasmosis?
chorioretinitis
hydrocephalus
intracranial calcifications
What is the treatment for toxoplasma?
sulfadiazine
pyrimethamine
folinic acid
WHat do you need to know about naegleria fowleri?
Nalgene-filled w/ fresh water
swimming in fresh water lakes
Naegleria enters cribriform plate–>meningoencephalitis
HOw do you treat naegleria fowleri?
amphotericin B
What are the important things to know about African Sleeping Sickness?
Trypanosoma brucei rhodesiense + gambiense
enlarged lymph nodes, fever, somnolence, coma, encephalitis
spread by tsetse fly
treated w/ suramin and melarsoprol (CNS penetration)
Sure is nice to sleep. Melatonin helps you sleep.
What are the important things to know about malaria?
Plasmodium Vivax/Ovale-tertian 48 hour cycle. dormant form in liver (hypnozoite).
Plasmodium malaria–72 hour cycle, quartan
Plasmodium Falciparum–most severe, occlude capillaries in brain, kidney, lungs.
Which bug spreads malaria?
Anopheles mosquito
When do you see schuffner stippling?
red granules seen in malaria seen in RBC cytoplasm of P vivax/ovale
What’s the deal with babesiosis?
northeastern US–ixodes tick
fever and hemolytic anemia
see Maltese cross and ring form on blood smear
What is the treatment for basesiosis?
atovaquone + azithromycin
quinine + clindamycin
What causes chagas disease?
Trypansoma Cruzi Everything gets big! cardiomyopathy megacolon megaesophagus found in South America **sometimes unilateral periorbital swelling (romana sign)
spread by reduviid bug (kissing bug)
What are the important features of Leishmania donovani?
causes visceral and cutaneous leishmaniasis
spread by sandfly
see macrophages w/ amastigotes (lack flagella)
What are the features of visceral leishmaniasis?
spiking fevers
HSM
pancytopenia
What is the treatment for leishmaniasis?
Amphotericin B–visceral
Sodium stibogluconate for cutaneous
What are the important features of trichomonas?
foul-smelling flagellated vaginal itching greenish discharge increases vaginal pH see trophozoites on wet mount get strawberry cervix treated w/ metronidazole.
Which protozoa are spread this way? sandfly reduviid bug ixodes tick tsetse fly anopheles mosquito?
sandfly--leishmaniasis reduviid bug--trypansoma cruz (chagas) ixodes tick-Lyme dx and babesiosis tsetse fly-trypansoma brucei anopheles mosquito-malaria
