protozoa

Question 1

Parasites are divided to

Answer 1

1. Protozoa

2. Helminthes

Question 2

Protozoa infections are divided to

Answer 2

1. GI infections
2. CNS infections
3. Hematologic infections
4. other infections (visceral infections and STD)

Question 3

Protozoa GI infections - bugs and diseases

Answer 3

1. Giardia lamblia - giardiasis
2. Entamoeba histolytica - amebiasis
3. Cryptosporidium - diarrhea

Question 4

Giardia lamblia - disease and symptoms / seen in

Answer 4

Giardiasis: 1. bloating 2. flatulence
3. foul smelling, fatty diarrhea
campers + hikers

Question 5

Giardia lamblia - transmission / diagnosis / treatment

Answer 5

cysts in water
multinucleated trophozoites or cysts in stool
treatment: metronidazole

Question 6

Entamoeba histolytica - disease and symptoms

Answer 6

Amebasis: 1. bloody diarrhea (dysentery)

2. liver abscess (anchovy paste exudate)
3. RUG pain

Question 7

Entamoeba histolytica - transmission / treatment

Answer 7

cysts in water
treatment: metronidazole
or iodoquinol for asymptomatic cyst passers
- a luminal agent, eg. paromomycin) is also recommended to eradicate intestinal colonizationcyst
- drainage is not recommended

Question 8

Entamoeba histolytica infection - diagnosis

Answer 8

• serology and/or
• trophozoites with RBCs in the cytoplasm
  or cysts with up to 4 nuclei in stool

Question 9

Cryptosporidium - disease and symptoms

Answer 9

severe nonbloody diarrhea in AIDS
Mild disease (watery diarrhea) in immunocompoment

Question 10

Cryptosporidium - transmission / diagnosis

Answer 10

oocysts in water

diagnosis: oocysts on acid-fast stain

Question 11

Cryptosporidium - treatment/prevention

Answer 11

prevention by filtering city water supplies
notazoxamide in immunocompetent hosts
no clear treatment for AIDS patient

Question 12

Protozoa - CNS infection - bugs and diseases

Answer 12

Toxoplasma gondi - toxoplasmosis
Naegleria fowleri - rapidly fatal meningoencephalitis
Trypanosoma brucei - African sleeping diseas

Question 13

Toxoplasma gondi infection and symptoms

Answer 13

1. Congenital toxoplasmosis –> classic triad of chorioretinitis, hydrocephalus, intracranial calcification
2. reactivation in aids –> brain abscess

Question 14

Toxoplasma gondi transmission

Answer 14

cysts in undercooked meat (MC)
oocysts in cat feces
crosses placenta

Question 15

Toxoplasma gondi - diagnosis

Answer 15

serology
biopsy (tachyzoite)
CT/MIR ring-enhancing lesion

Question 16

Trypanosoma brucei - disease and symptoms

Answer 16

African sleeping disease: 1. enlarged lymph nodes

2. recurring fever 3. somnolence 4. Coma

Question 17

African sleeping disease - transmission / diagnosis

Answer 17

Tsetse fly, a painful bit

diagnosis: Trypomastigote in blood smear

Question 18

African sleeping disease - treatment

Answer 18

suramin for blood-borne disease

melarsoprol for CNS penetration

Question 19

Naegleria fowleri - diagnosis

Answer 19

amoebas in spinal fluid

Question 20

Malaria - fever according to bug

Answer 20

P. vivax/ovale –> 48hr cycle (tertian: fever on first day and third day, thus fever are actually 48hr apart)
P. falciparum –> severe. irregular fever pattern
P. malariae –> 72 hr cycle (quartan)

Question 21

other complications of malaria, beside general symptoms

Answer 21

occlude capillaries in brain (cerebral malaria), kidney, lung (esp with P. Falciparum)

Question 22

Malaria - relapse vs recrudescence

Answer 22

Relapse occurs in P. vivax and P. ovale infection ressults from hypnozoites –> reactivation of hypnozoites in liver
Recrudescence occurs in P. malariae and P. falciparum infections and results from incomplete eradication of the parasites

Question 23

Malaria - diagnosis

Answer 23

1. Blood smear: trophozoites ring within RBCs, schizont containing merozoites
2. Red granules (Schuffner stippling) through RBC cytoplasm seen with P. vivax/ovale

Question 24

Malaria - treatment for every situation

Answer 24

1. Chloroquine (for sensitive species)
2. Mefloquine or atovaquone/proquanil (for resistant)
3. IV quinidine or artesunate (If life threatening) –> test for G6PD
4. P. vivax/ovale add primaquine for hypnozoite –> test for G6PD

Question 25

Protozoa visceral infections - bugs and disease

Answer 25

1. Trypanosoma cruzi --> Chagas disease | 2. Leishmania donovani --> Visceral leishmaniasis (kala-azar), cutaneous leismaniasis

Question 26

Leishmania donovani - disease and symptoms / aka

Answer 26

``` A. Visceral leishmaniasis (kala-azar): 1. spiking fevers 2. hepatosplenomegaly 3. pancytopenia B. cutaneous leismaniasis: 1. Skin ulcers ```

Question 27

Leishmania donovani - transmission

Answer 27

sandfly

Question 28

Visceral leishmaniasis (kala-azar) - diagnosis / treatment

Answer 28

macrphages contating amastigotes amphotericin B sodium stibogluconate

Question 29

Trypanosoma cruzi - disease / map / transmission

Answer 29

Chagas disease SOUTH AMERICA transmission: Reduviid bug (kissing bug) feces, deposited in a painless bite

Question 30

Chagas disease sign

Answer 30

ROMANA SIGN: unilateral periorbital swelling --> characteristic of acute stage

Question 31

chagas disease - diagnosis / treatment

Answer 31

Trypomastigote in blood smear | - Benzidazole or nifurtimox

Question 32

Protozoa sexual transmitted infections - bugs and disease / symptoms

Answer 32

Trichomonas vaginalis --> vaginitis --> foul-smelling, greenish discharge, itching and burning

Question 33

bacterial vaginosis vs protozoal vaginitis according to

Answer 33

vaginitis: foul-smelling, greenish discharge, itching and burning Bcterial vaginosis: gray vaginal discharge with fishy smell, nonpainful

Question 34

Trichomonas vaginalis - outside human form

Answer 34

cannot exits outside human because it cannot form cysts

Question 35

Trichomonas vaginalis - diagnosis / treatment

Answer 35

trophozoites (motile) on wet mount strawberry cervix - Metronidazole for patient and partner (prophylaxis)

Question 36

treatment for all protozoal infections (except malaria)

Answer 36

Giardiasis --> Metronidazole amebiasis --> metronidazole, iodoquinol for asymptomatic cyst passers cryptosporidium --> prevention by filtering city water supplies, nitazoxanide in immunocompetent, no clear treatment for aids Toxoplasma gondi --> Sulfadiazine+pyrimethamine Naegleria fowleri --> Amphotericin B Trypanosoma brucei --> Suramin for blood-borne disease or melarsoprol for CNS penetration Babesia --> atovaquone + azithromycin Tripanosoma cruzi --> Benzidazole or nifurtimox Leishmania donovavi --> amphotericin sodium stibogluconate trichomonas vaginalis --> Metronidazole for patient and partner (prophylaxis)

Question 37

Babesiosis - epidimiology / diagnosis

Answer 37

ixode scapularis like lyme and anaplasmosis | thin blood smear: intraerythrocytic rings (Maltese cross)

Question 38

Babsiosis - manifestation

Answer 38

- flu like - if severe: ARDS, CHF, DIC, splenic rupture - anemia, thrombocytopenia, increased bilirubinm LDH, LFTs

Question 39

Babesia - treatment

Answer 39

- atovaquone + azithromycin | - Quinine + clindamycin (if severe)

Question 40

RFs for severe babesiosis

Answer 40

1. immonucompr 2. splenectomy 3. older than 50

Question 41

complications of malaria in children

Answer 41

seizure, coma, hypoglycemia, met acidosis

Question 42

complications of malaria in adults

Answer 42

jaundice, acute renal failure, acute pulm edema

Question 43

C. parvum in immunocomprement

Answer 43

traveler's diarrhea - prolonged, profuse, watery - self limited in 10-14 days

Question 44

E. histolytica - most common symptom

Answer 44

asymptomatic (only 10% has colitis) `

Question 45

malaria prevention

Answer 45

travelers new to endemic areas require chemoprophylaxis atovaquone - proguanil, doxycycline or melfoquine (2 weeks prior to travels, continued during statyy, discont 4 weeks after returning other measures to protect from mosquitos

Question 46

toxoplasmic encephalitis - stereotactic brain biopsy

Answer 46

only if not respond to antibiotic