Protozoa Flashcards
(39 cards)
what are the symptoms of Giardiasis and how do you diagnose it?
Giardia lamblia causes bloating, flatulence and fatty, foul-smelling diarrhea; diagnosed via cycsts or trophozoites in the stool
how is Giardia transmitted and how is it treated?
transmitted via cysts in the water; treated with metronidazole
what are the symptoms of cryptosporidium in AIDS patients vs. nonimmunocompromised patients
severe diarrhea in AIDS patients; mild water diarrhea in noncompromised host
how are cryptosporidium and entamoeba histolytica transmitted
cysts in water
how is cryptosporidium diagnosed
cysts on acid-fast stain
how is entamoeba histolytica diagnosed
serology, trophozoites and/or multinuceated cysts in stool
what organism causes Amebiasis and what are the symptoms
Entamoeba histolytica causes Amebiasis; symptoms include dysentery, liver abscess (with “anchovy paste” exudate), RUQ pain, submucosal abscess of colon
how do you treat symptomatic vs. asymptomatic amebiasis
symptomatic: metronidazole
asymptomatic: iodoquinol
how is crytosporidium treated in immunocompetent hosts?
nitazoxanide
what symptoms does toxoplasma gondii cause in HIV patients and in children born of infected mothers
brain abscess in HIV (ring-enhancing lesions); congenital toxoplasmosis causes “classic triad” of chorioretinitis, hydrocephalus, and intracranial calcifications
how is toxoplasmosis diagnosed? treated?
diagnosed via serology or biopsy; sulfadiazine + pyrimethamine
what does Naegleria fowleri cause
rapidly fatal meningoencephalitis
how is Naegleria fowleri contracted?
swimming in freshwater lakes, it enters via the cribiform plate
how is Naegleria fowleri diagnosed? treated?
amoebas in spinal fluid; amphotericin
what are the three main species of Trypanosoma that cause CNS problems
brucei, gambiense, rhodesiense
what are the symptoms of Trypanosoma
African sleeping sickness: enlarged lymph nodes, recurring fever (due to antigenic variation), somnolence, coma
how is Trypanosoma contracted? diagnosed?
painful bite by tsetse fly; diagnosed via blood smear
how is Trypanosoma treated?
suramin for blood-borne disease
melarsoprol for CNS penetration
name the four main types of Plasmodium
falciparum, vivax, ovale, malariae
what are the symptoms of malaria
fever, headache, anemia, splenomegaly
what are the differences in fevers from falciparum vs. vivax/ovale vs. malariae
falciparum= irregular fever vivax/ovale= 48 hour cycle malariae= 72 hour cycle
what organs are affected by falciparum and how?
occlusions by parasitized RBCs in brain (cerebral malaria), kidneys and lungs
how is malaria treated?
chloroquine which blocks Plasmodium heme polymerase; use mefloquine if resistant
if life-threatening use intravenous quinidine (if patient doesn’t have G6PD def.)
add primaquine for vivax/ovale for hypnozoite (if pt. doesn’t have G6PD def.)
how is malaria dianosed?
trophozoite ring form on blood smear, RBC shizont with merozoites on blood smear
