Microbio-Parasitology And Protozoa Flashcards
(35 cards)
Diagnosis: Serology and/or trophozoites (w/RBC in the cytoplasm); or cysts with up to 4 nuclei in stool.
Disease: bloody diarrhea, liver abscess (anchovy paste exudate), RUQ pain (histol. shows flask-shaped ulcer if colon rupture.
Transmission: cysts in water
Treatment: Metronidazole; iodoquinol for asymptomatic cyst passers.
Entamoeba histolitica
Diagnosis: Trophocytes, or cysts in stool.
Disease: Bloating, flatulence, foul-smelling, fatty diarrhea.
Transmission: cysts in water
Giardia lamblia- Giardiasis
Diagnosis: Oocyts on acid-fast stain.
Disease: Severe diarrhea in AIDS; Mild disease (watery diarrhea) in nonimmunocompromised.
Transmission: Oocysts in water
Treatment: Prevention by filtering H2O in city water supplies, treatment with nitazoxanide in immunocompetent hosts.
Cryptosporidium
Diagnosis: Serology, biopsy (tachyzoite)
Disease: Brain abscess in HIV (seen as ring-enhancing brain lesions on CT/MRI); congenital **=classic triad of chorioretinitis, hydrocephalus, and intracranial calcifications.
Transmission: cysts in meat or oocyts in cat feces; crosses placenta.
What is the organism and the treatment?
Toxoplasma gondii
*toxoplasmosis
Treatment: Sulfadiazine + pyrimethamine
And W/a CD4+ <100 - TMP-SMX
Diagnosis: Ameobas in spinal fluid.
Disease: rapidly fatal meningoencephalitis
Transmission: Swimming in freshwater lakes containing the organism; enters via cribriform plate. What is the microorganism and the treatment?
Naegleria fowleri
Treatment: Amphotericin B has been effective for a few survivors.
Diagnosis: Blood smear
Disease: African sleeping sickness: enlarged lymph nodes, recurring fever (due to antigenic variation), somnolence, coma
Transmission: Tsete fly, a painful bite
What is the microorganism and treatment?
Trypanosoma brucei
Treatment: Suramin for blood-borne disease or melarsoprol for CNS penetration
Diagnosis: Blood smear, ring form, “Maltese cross”; PCR
Disease: Fever and hemolytic anemia; predominantly in NE and North central US; asplenia increases the risk of severe disease.
Transmission: Ixodes tick, same as Lyme disease-may coinfect human
What is the microorganism and treatment?
Babesia - Babesiosis
Treatment: Atovaquone + azithromycin
Disease: fever, headache, anemia, splenomegaly. 48h-cycle: fever on first day and third day (thus 48h); dormant form in liver (hypnozoite).
Transmission: Mosquito (anopheles)
Treatment: Begin with chloroquine, which blocks **** heme polymerase + primaquine
Diagnosis: Blood smear, trophozoite ring form within RBC, schizont containing merozoites.
Plasmodium vivax/ ovale - Malaria
Disease: fever, headache, anemia, splenomegaly. Severe, irregular fever patterns; parasitized RBCs occlude capillaries in brain, kidneys, lungs.
Transmission: Mosquito (anopheles)
Treatment: Begin with chloroquine, which blocks _________ heme polymerase, if resistant: use mefloquine or atovaquone/proguanil
Plasmodium falciparum- (May present cerebral malaria)
Disease: fever, headache, anemia, splenomegaly, 72-hr cycle (quartan).
Transmission: Mosquito (anopheles)
Treatment: Begin with chloroquine, which blocks______ heme polymerase, if resistant: use mefloquine or atovaquone/proguanil
Diagnosis: Blood smear, trophozoite ring form within RBC, schizont containing merozoites.
Plasmodium malariae- malaria
Diagnosis: Macrophages containing amastigotes
Disease: Kala-afar: spiking fevers, hepatosplenomegaly, pancytopenia
Transmission: Sandfly
What is the treatment?
Leishmania donovani
Treatment: Amphotericin B, sodium stibogluconate
Diagnosis: Trophozoites (motile) on wet mount; strawberry cervix.
Disease: Foul-smelling, greenish discharge; itching and burning.
Transmission: Sexual (cannot exist outside human because it cannot form cysts).
Treatment: Metronidazole for Px and partner (prophylaxis).
Trichomonas vaginalis - causes vaginitis.
Disease: intestinal infection causing perianal pruritus (diagnosed via the Scotch Tape test).
Transmission: Fecal-oral
What is the microorganism and treatment?
Enterobius vermicularis- pinworm
Treatment: Bendazoles or pyrantel pamoate
Disease: intestinal infection, may cause obstruction at ileocecal valve, biliary obstruction, intestinal perforation, and migrates from nose/mouth.
Transmission: Fecal oral; eggs visible in feces under microscope
What is the microorganism and treatment? What complication can occur if larvae migrate to alveoli?
Ascaris lumbricoides- giant roundworm
Treatment: Bendazoles or pyrantel pamoate
Complication: Loeffler Syndrome (pulmonary eosinophilia)
Disease: GI infection (duodenitis), pulmonary (causing dry cough, hemoptysis), and cutaneous pruritus.
Transmission: Larvae in soil penetrate the skin.
What is the microorganism and treatment?
Strongyloides stercoralis (threadworm)
Treatment: Ivermectin or bendazoles
Disease: Intestinal infection causing anemia by sucking blood from intestinal wall
Transmission: Larvae penetrate skin from walking barefoot on sand or soil.
What is the microorganism and treatment?
Ancylostoma duodenale, Necantor americanus (hookworms).
Treatment: Bendazoles or pyrantel
Disease: Hyperpigmented skin and river blindness, black skin nodules; allergic reaction to microfilaria possible.
Transmission: Female blackfly bite.
Treatment: Ivermectin
Onchocerca volvulus
Disease: Swelling in skin, worm in conjunctiva
Transmission: Deer fly, horse fly, mango fly.
Treatment: Diethylcarbamazine
Loa Loa
Disease: Blocks lymphatic vessels: elephantiasis; takes 9mo-1yr after bite to become symptomatic
Transmission: Female mosquito
Treatment: Diethylcarbamazine
Wuchereria bancrofti - elephantiasis
Disease: Visceral larva migrans into blood—> inflammation of liver, eyes (visual impairment), CND seizures and coma, and myocarditis.
Transmission: Fecal-oral
what is the microorganism and treatment?
Toxocara canis
Treatment: Bendazoles
Disease: Intestinal infection
Transmission: Ingestion of larvae encysted in undercooked pork.
Treatment: Praziquantel
Taenia solium - (tapeworms)
Disease: Cysticercosis, neurocysticercosis - brain cysts, seizures.
Transmission: Ingestion of eggs
Treatment: Praziquantel; albendazole for neurocysticercosis
Taenia solium - (tapeworms)
Disease: Vitamin B12 deficiency (tapeworm competes for B12 in intestine) –> anemia
Transmission: Ingestion of larvae from raw freshwater fish
Treatment: Praziquantel
Diphyllobothrium latum - (tapeworms)
Disease: hydrated cysts in liver, causing anaphylaxis if antigens released (surgeons preinject with ethanol to kill cysts before removal).
Transmission: Ingestion of eggs from dog feces
Treatment: Albendazole
Echinococcus granulosus - cestodes (tapeworms)
