Protozoa Flashcards
What are the forms of Entamoeba histolitica? Which is the infective form?
Cyst- Infective form
Trophozoite- motile, feeding form
What is the most common site of abscess formation if E. histolytica trophozoites penetrate portal blood circulation?
Liver- Cause RUQ pain
What would be present in the stool sample of a person with active disease from Entamoeba histolytica?
Trophozoites with RBC’s in the cytoplasm
What type of symptoms are characteristic of a Giardia infection?
Abdominal gas, distention
Greasy, frothy diarrhea with bad odor
Where does the life cycle of Cryptosporidium take place?
Intestinal epithelial cells
What protozoa is sexually transmitted and only has a trophozoite stage?
Trichomonas vaginalis
What organism passes through the cribriform plate and causes acute meningoencephalitis? Classic patient history?
Naegleria fowleri
Hx of swimming in fresh water
What is the most common CNS infection in AIDS patients?
Toxoplasma encephalitis
How might an AIDS patient with Toxoplasma encephalitis present?
With seizures, gait instability, HA, focal neurologic signs, often involving a growing mass (seen on CAT scan)
What is the most common opportunistic infection in AIDS patients?
Pneumocystis carinii pneumonia
What protozoa is transmitted via the Reduviid bug (Kissing bug)?
Trypanosoma cruzi- Chagas disease
What is the cause of River blindness? What is the vector?
Onchocera volvulus
Blackfly bite
What protozoa stains acid-fast and causes severe diarrhea in AIDS patients?
Cryptosporidium parvum
What does congenital Toxoplasmosis lead to in a fetus?
Chorioretinitis, hydrocephalus, and intracrainial calcifications, microcephaly
What causes African Sleeping Sickness? What is the vector?
Trypanosoma brucei
Transmitted via Tsetse fly
What types of malaria produce dormant hypnozoites in the liver?
Plasmodium vivax and ovale
What is the difference between tertian and quartan malaria?
Tertian- RBC lysis every 48 hours (P. vivax/ovale)
Quartan- RBC lysis every 72 hours (P. malariae)
What is the vector for Leishmaniasis?
The Sandfly
What are the classic presentations for chronic Chagas disease?
Cardiomyopathy, megacolon, and esophageal dilation, LES hypertrophy, difficulty swallowing
How would a wet mount of Trichomonas vaginalis and Gardnerella vaginosis differ?
Trichamonas- motile, pear-shaped flagellates
Gardnerella- clue cells
