Protozoans

Question 1

What are the sources of exposure of Cryptoisospora?

Answer 1

Person to person (daycare, family)-oocysts are infectious when shed ; Drinking water (very resistant to chlorination); Recreational water (swimming pools); Contaminated food; Animals

Question 2

Cryptosporidiosis in resource poor countries

Answer 2

children <24 months, AIDS, Acute diarrhea, wasting, can be prolonged>7 days

Question 3

Cyrptosporidiosis in HIV
CD4>180
CD4<100
CD4<50

Answer 3

> 180: self limited
<100, chronic
<50, Severe, cholera like
<50, biliary tract involvement

Question 4

Answer 4

Cryptospoidiosis

Question 5

Protozoa that can cause sclerosing cholangitis, papillary stenosis, acalculous cholecystitis, RUQ pain.

Answer 5

Cryptosporidiosis , usually in HIV

Question 6

Treatment of cryptosporidiosis

Answer 6

self limited usually; fluids/electrolytes
If immunocompromised, consider nitazoxanide or paromomycin +azithromycin)

Question 7

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

Answer 7

cyclospora cayetanensis

Question 8

Where is cyclospora cayetanensis endemic

Answer 8

Peru, Haiti, Nepal (also africa, caribbean); can have outbreaks from raspberries as well

Question 9

Life cycle of cyclospora cayetanensis

Answer 9

Food chain contamination–>ingest the sporulated oocyst–>excretion of unsporulated oocysts int he stool–>unsporulated oocyst infects food etc

Question 10

Host of cyclospora cayetanensis

Answer 10

HUMANS (oocysts are not immediate infectious, so no person to person)

Question 11

Difference between cryptosporidium and cyclospora

Answer 11

Person to person transmission with crypto

Question 12

Auto fluorescence under UV light, protozoa

Answer 12

Cyclospora Cayatensis

Question 13

Treatment of cyclospora

Answer 13

TMP/SMX

Question 14

Round oocyst, 8-10um

Answer 14

Cyclospora

Question 15

which protozoa causes eosinophilia

Answer 15

cystoisospora belli

Question 16

what is the difference between cyrpto and cyclospora/cystoisospora

Answer 16

cyclospora/cystoisospora are in the cytoplasm

Question 17

coccidian parasites by size, treatment

Answer 17

Question 18

AIDS patient with severe watery diarrhea, volume depletion

Answer 18

Microsporidium

Question 19

Treatment of microsporidiosis

Answer 19

asymptomatic/self limited in immunocompetent
In AIDS: ART

Question 20

common childhood diarrhea, diarrhea/biliary AIDS patients, transplant pt

Answer 20

cryptosporidium

Question 21

Diarrhea AIDS, Keratoconjunctiviis, rare myositis

Answer 21

Microsporidia

Question 22

How to diagnose intestinal protozoa

Answer 22

PCR, AFB stain, Ag detection

Question 23

What are the evolutive forms of trypanosoma cruzi

Answer 23

Amastigote (TISSUES)
Epimastigote (VECTOR)
Trypomastigote (Infective blood form)

Question 24

Vectors of Chagas

Answer 24

Trypanosoma Cruzi: Triatoma, Panstrongylus, Rhodnius

Question 25

Toxoplasmosis: What is the definitive host? What ist he intermediate host? How is it acquired?

Answer 25

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)

Question 26

Symptoms of acute infection of toxo

Answer 26

mono like syndrome 80-90% immunocompetent asymptomatic

Question 27

LAD, Mono-like, chorioretinitis, hepatitis, myocarditis, pneumonitis, focal abscess-AIDS

Answer 27

toxoplasmosis (toxoplasma gondii)

Question 28

Answer 28

Toxoplasma gondii Cotton wool spots

Question 29

When you have cerebral toxo, what are you concerned about?

Answer 29

Re-activation in AIDS -cause cerebral lesions

Question 30

What is the most common infectious cause of posterior uveitis in south america

Answer 30

posterior uveitis

Question 31

what happens with latent infection

Answer 31

bradyzoites in the tissue cysts in immunocompromised individuals causes reactivation

Question 32

What is the diagnosis of Toxoplasma

Answer 32

IgM and IgG PCR

Question 33

If immunocompetent and NOT pregnant and active chorioretinitis

Answer 33

pyrimethamine and sulfadiazine (can add prednisone until CSF protein falls or vision improves)

Question 34

For prevention of recurrent episodes of chorioretinitis in toxo

Answer 34

TMP-SMX

Question 35

If acute illness in pregnancy with toxoplasma, how to treat

Answer 35

If diagnosed <16-18 weeks of gestational age: Spiramycin If >16-18 weeks of gestational age , pyrimethamine and sulfadiazine and folinic acid

Question 36

If Fetal toxo, congenital

Answer 36

pyrimethamine + sulfadiazine + leucovorin

Question 37

Toxoplasma encephalitis treatment

Answer 37

consider brain biopsy if 7-10 days of no improvement after treatment -Pyrimethamine Sulfadiazine + Folonic acid and then TMP/SMX for secondary suppression