Flashcards in Micro 29 - Protozoa Deck (63)
How is cryptosporidium spread and can we remove it from the source?
Transmitted by oocysts in water or person to person. Filtration removes oocysts from water.
How does one get infected with Giardia lamblia what are the symptoms?
Ingested cysts turn into trophozoites that interfere with fat absorption. It causes acute, fatty, foul-smelling diarrhea, flatulence, and abdominal bloating.
How is the diagnosis of Giardia lamblia made?
Pear-shaped trophozoites or cysts in stool.(O and P).
What is the treatment for Giardia lamblia?
Metronidazole or Tinidazole.
What does Entomaoeba histolytica cause?
Amebiasis causing bloody diarrhea, causing Amoebic dysentery. Can perforated colon, causing a flask-shaped ulcer with a narrow opening and submucosal ulceration. Can also cause liver abscesses causing RUQ pain.
How is Entamoeba histolytica spread?
Transmitted through fecal-oral route.
How is Entamoeba histolytica diagnosed?
Trophozoites or cysts in stool (may see ingested RBC's). (O an P).
Or serology, or stool antigen.
What is the treatment for Entamoeba histolytica?
Kill trophozoites with Metronidazole > Tinidazole. Kill the cysts that may remain in the intestine with Iodoquinol or paromomycin.
On which infections do we use Metronidazole?
"GET GAP on the Metro!"
Pylori (H. pylori).
What is the most common protozoal infection in the US?
What are the symptoms of Trichomonas vaginalis and how is it spread?
"The three F's for Trichomonas vaginalis"
Causes vaginitis and a foul-smelling, greenish vaginal discharge. Primarily transmitted through sexual activity.
How is Trichomonas vaginalis diagnosed?
A wet mount of vaginal discharge, looking for trophozoites (pear shaped and move around fast in their characteristic twitching motion.)
What are the similarities and diferences of Trichomoniasis and bacterial vaginosis (BV)?
Both are due to increase of vaginal pH and are treated with metronidazole.
Trichomoniasis is caused by sexually transmitted protozoan while the latter is caused by overgrowth of anaerobe (Gardnerella vaginalis).
Why are cats so important in Toxoplasma gondii?
Cats are the only host where the protozoan can complete it's reproductive cycle.
How is toxoplasma gondii transmitted to humans?
Handling of cat feces or litter because of oocysts that are liberated through the cat. Or by eating cysts infected meats.
What does toxoplasmosis cause in the brain of AIDS patients?
Ring enhancing lesions in the brain in MRI of AIDS patients.
What is the classic triad that Congenital toxoplasmosis cause on the fetus?
3. Intracranial calcifications.
How is toxoplasmosis diagnosed?
Serology or biopsy (because primary CNS lymphoma can also present as ring enhancing lesion on MRO).
What is the treatment for toxoplasmosis?
Sulfadiazine + pyrimethamine + folinic acid.
What is naegleria fowleri and what does it cause and how is it transmitted?
It is a ameba that causes rapidly fatal meningoencephalitis. Transmission from swimming in freshwater lakes. Enters nose and passes through cribriform plate to brain.
What is the treatment for Naegleria fowleri?
Amphotericin B (offlabel use) but few people have gotten the treatment in time to survive the infection.
What does cryptosporidium cause in AIDS patients?
Chronic, watery diarrhea.
What is Trypanosomiasis and what are the 2 relevant subspecies?
It is the bacteria that causes African sleeping sickness.
It is caused by Trypanosoma brucei rhodesiense and Trypanosoma brucei gambiense.
How is trypanosomiasis transmitted?
Blood-borne by vector, specifically through the tsetse fly.
What are the symptoms of African sleeping sickness?
A bloodstream infection, it causes fever, enlarged lymph nodes and somnolence. Late stage infection involves encephalitis, coma and death.
How is trypanosomiasis diagnosed?
Bloodsmear, long, wispy looking organisms in the blood.
What is the treatment for trypanosomiasis?
Suramin for early bloodstream infection. Melarsoprol for CNS involvement.
What does Trypanosoma cruzi cause?
How is Chagas disease transmitted?
By the reduviid bug, the "kissing" bug. It is a painless bite but it defecates, and the bacteria is in the dropping. The human scratches the site of bite near the dropping and that is how it gets infected.