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Flashcards in Protozoa Deck (14):
1

Giardia lamblia

p/w giardiasis
tranmission
dx
tx

giardiasis = bloating, flatulene, foul smelling fatty diarrhea

cyts in water

multinucleated trophozoites/ cysts in stool/antigen detection

metronidazole

2

Entamoeba histolytica

p/w amebiasis
transmission
dx
tx

amebiasis = bloddy diarrhea (dysentary), liver abscess & RUQ pain, flask shaped ulcers on colon bx

cysts in water

trophozoites with engulfed RBCs or up to 4 nuclei
serology or antigen

metronidazole
paromomycin or iodoquinol for asx cyts passers

3

Cryptosporidium

p/w
tranmission
dx
tx

Severe diarrhea in AIDS
mild watery diarrhea in immunocompetent

oocysts in water

oocyst on acid fast stain; antigen

immunocompetent - nitazoxanide
prevention

4

Toxoplasm gondii

p/w immunocompetent, reactivation in AIDS, congenital
tramission
dx
tx

immunocompetent - mononucleosis like syndrome w/ (-) monospot test
AIDS - brain abscesses - multiple ring enhancing lesions on MRI
congenital - IC calcifications, hydrocephalus, chorioretinitis

cysts in meat; oocysts in cat feces; crosses placenta

serology; bx (tachyzoite)

sulfadiazine + pyrimethamine

5

Naegleria fowleri

p/w
transmission
dx
tx

rapidly fatal meningoencephalitis

swimming in fresh water; enters cribiform plate

ameobas in CSF

amphotericin B; very fatal

6

Trypanosoma brucei

p/w African sleeping sickness
transmission
dx
tx

african sleeping sickness:
enlarged LNs, recurring fever, somnolence, coma

tsetse fly, painful bite

trypomastigote on blood smear

suramin - blood bourne dx
melarsoprol - CNS penetration

7

Plasmodium

p/w malaria
tranmission
dx
tx (general)

fever, H/A, anemia, splenomegaly

anopheles misquito

blood smear: trophozite ring form w/in RBC
schizont containing merozoites

chloroquine (blocks plasmodium heme polymerase)
if resistant: mefloquine or atovaquone/proguanil
if life threatening: IV quinidine or artesunate
(test for G6PD def)

8

Plasmodium vivax/ovale

cycle
blood smear
tx

48hr cycle:
dormant form/hypnozoite lives in liver
fever on 1st & 3rd days, 48hrs apart

red granules throughout RBC cytoplasm
*Schuffner staining

add primaquine for hypnozoite

9

Plasmodium falciparum

cycle
virulence

severe

irregular fever patterns

parasitized RBCs occlude capillaries in brain, kidney & lungs

10

Plasmodium malariae
cycle

72 hr cycle (quartan)

11

Babesia

p/w babesiosis
transmission
dx
tx

fever & hemolytic anemia (increased UCB)
in NE US
asplenia increased risk for sever dx

ixodes tick

blood smear: ring form, maltese cross
PCR

atovaquone & azithromycin

12

Trypanosoma cruzi

p/w Chagas dx
transmission
dx
tx

Chagas dx
= DCM w/ apical atrophy, megacolon, megaesophagus & u/l periorbital swelling in acute stage

triatomine bug ("kissing bug") - deposites feces in painless bite

blood smear: trypomastigote

benznidazole or nifurtimox

13

Leishmania donovani

p/w visceral leishmaniasis, cutaneous leishmaniasis
transmission
dx
tx

visceral leishmaniasis
= spiking fevers, HSM, pancytopenia
cutaneous leishmaniasis
= skin ulcers

sandfly

blood smear: macrophages w/ amastigotes

amphotericin B, stibogluconate

14

Trichomonas vaginalis
p/w vaginitis
transmission
dx
tx

vaginitis
= foul smelling greenish d/c, vaginal inflammation, ph >4.5
itching, burning

STI

trophozoites on wet mount, strawberry cervix

metronidazole, tx partner