Protozoans Flashcards
What are the sources of exposure of Cryptoisospora?
Person to person (daycare, family)-oocysts are infectious when shed ; Drinking water (very resistant to chlorination); Recreational water (swimming pools); Contaminated food; Animals
Cryptosporidiosis in resource poor countries
children <24 months, AIDS, Acute diarrhea, wasting, can be prolonged>7 days
Cyrptosporidiosis in HIV
CD4>180
CD4<100
CD4<50
> 180: self limited
<100, chronic
<50, Severe, cholera like
<50, biliary tract involvement
Cryptospoidiosis
Protozoa that can cause sclerosing cholangitis, papillary stenosis, acalculous cholecystitis, RUQ pain.
Cryptosporidiosis , usually in HIV
Treatment of cryptosporidiosis
self limited usually; fluids/electrolytes
If immunocompromised, consider nitazoxanide or paromomycin +azithromycin)
27yoF with 4 weeks of watery diarrhea, >5 x day. No blood, no mucus, +fatigue, nausea, anorexia. Travels around nepal for 4 months s/p flagyl but no improvement
cyclospora cayetanensis
Where is cyclospora cayetanensis endemic
Peru, Haiti, Nepal (also africa, caribbean); can have outbreaks from raspberries as well
Life cycle of cyclospora cayetanensis
Food chain contamination–>ingest the sporulated oocyst–>excretion of unsporulated oocysts int he stool–>unsporulated oocyst infects food etc
Host of cyclospora cayetanensis
HUMANS (oocysts are not immediate infectious, so no person to person)
Difference between cryptosporidium and cyclospora
Person to person transmission with crypto
Auto fluorescence under UV light, protozoa
Cyclospora Cayatensis
Treatment of cyclospora
TMP/SMX
Round oocyst, 8-10um
Cyclospora
which protozoa causes eosinophilia
cystoisospora belli
what is the difference between cyrpto and cyclospora/cystoisospora
cyclospora/cystoisospora are in the cytoplasm
coccidian parasites by size, treatment
AIDS patient with severe watery diarrhea, volume depletion
Microsporidium
Treatment of microsporidiosis
asymptomatic/self limited in immunocompetent
In AIDS: ART
common childhood diarrhea, diarrhea/biliary AIDS patients, transplant pt
cryptosporidium
Diarrhea AIDS, Keratoconjunctiviis, rare myositis
Microsporidia
How to diagnose intestinal protozoa
PCR, AFB stain, Ag detection
What are the evolutive forms of trypanosoma cruzi
Amastigote (TISSUES)
Epimastigote (VECTOR)
Trypomastigote (Infective blood form)
Vectors of Chagas
Trypanosoma Cruzi: Triatoma, Panstrongylus, Rhodnius
Toxoplasmosis: What is the definitive host? What ist he intermediate host? How is it acquired?
Toxoplasma Gondii, FElines are definitive host, humans and other animals are intermediate hosts, it may be acquired by ingestion of cysts with bradyzoites (raw meat), oocysts with sporozoites (cat feces) or congenital (transplacenta)
Symptoms of acute infection of toxo
mono like syndrome
80-90% immunocompetent asymptomatic
LAD, Mono-like, chorioretinitis, hepatitis, myocarditis, pneumonitis, focal abscess-AIDS
toxoplasmosis (toxoplasma gondii)
Toxoplasma gondii
Cotton wool spots
When you have cerebral toxo, what are you concerned about?
Re-activation in AIDS -cause cerebral lesions
What is the most common infectious cause of posterior uveitis in south america
posterior uveitis
what happens with latent infection
bradyzoites in the tissue cysts in immunocompromised individuals causes reactivation
What is the diagnosis of Toxoplasma
IgM and IgG
PCR
If immunocompetent and NOT pregnant and active chorioretinitis
pyrimethamine and sulfadiazine (can add prednisone until CSF protein falls or vision improves)
For prevention of recurrent episodes of chorioretinitis in toxo
TMP-SMX
If acute illness in pregnancy with toxoplasma, how to treat
If diagnosed <16-18 weeks of gestational age: Spiramycin
If >16-18 weeks of gestational age , pyrimethamine and sulfadiazine and folinic acid
If Fetal toxo, congenital
pyrimethamine + sulfadiazine + leucovorin
Toxoplasma encephalitis treatment
consider brain biopsy if 7-10 days of no improvement after treatment
-Pyrimethamine Sulfadiazine + Folonic acid and then TMP/SMX for secondary suppression
