Parasites

Question 1

Giardia lambia treatment

exam question

Answer 1

Metronidazole or other azole

Question 2

Toxoplasma gondii treatment

Answer 2

Spiromycin or Pyrimethamine/Sulfadiazine

Question 3

Schistosomes treatment

Answer 3

Praziquantel

Question 4

Filariasis treatment

Answer 4

1. Ivermectin

2. Diethylcarbamazine

Question 5

Babesia microti treatment

Answer 5

1. Clindamycin + quinone

2. Atovaquone + azithromycin

Question 6

Cestodes/trematodes treatment

Answer 6

Praziquantel

Albendazole, etc

Question 7

Nematodes treatment

Answer 7

1. Albendazole
2. Pyrantel pamoate
3. Ivermectin
4. Diethylcarbamazine

Question 8

95% of malaria deaths are due to _____

Answer 8

P. falciparum

Question 9

Calling card of malaria

Answer 9

Flu-like symptoms

Cyclic high fever/chills/rigors every 48-72 hours

Question 10

Which Plasmodium sp. is most prevalent?

Answer 10

P. vivax

Question 11

What is significant about P. vivax and P. ovale?

Answer 11

Contain a latent form of the parasite found in the liver, which can cause relapse. Require additional treatment with Primaquine.

Question 12

Cardiomegaly occurs in 1/3 of patients affected with which parasite?

Answer 12

Trypanosoma cruzi

Question 13

What animal is the most likely source of Trichinella infection to humans in the U.S.?

Answer 13

Bear

Question 14

What is a definitive host?

Answer 14

The host in which the mature or sexually mature parasite lives

Question 15

What is an intermediate host?

Answer 15

The organism in which the parasite develops

Question 16

What is a trophozoite?

Answer 16

Metabolically active, usually motile stage. Replication.

Question 17

What is a cyst?

Answer 17

Non-motile form of parasite, protected by a membrane. Infective stage.

Question 18

What is a vector?

Answer 18

A living carrier that transports the parasite from infected to non-infected host.

Question 19

How do protozoa reproduce?

Answer 19

Budding, schizogony, sexually

Question 20

What is schizogony?

Answer 20

Multiple divisions of the nucleus before cell division

Question 21

What is significant about Entamoeba histolytica?

Answer 21

It is an invasive organism.

Question 22

Entamoeba histolytica is transmitted by ______, but not by ______.

Answer 22

Contaminated water / undercooked meat

Question 23

Structural significance of Entamoeba histolytica cyst

Answer 23

4 nuclei

Thick wall

Question 24

Calling card of Entamoeba histolytica

Answer 24

Inflammation – deep and then lateral, causing “tear-drop, flask-shaped” ulcers

Question 25

Major clinical manifestations of Entamoeba histolytica

Answer 25

Watery stools containing mucus and blood Ulcers Hepatic infection/abscess

Question 26

Giardia lamblia reservoir

Answer 26

Humans and animals

Question 27

Giardia lamblia associated with what conditions?

Answer 27

Crowded conditions--prisons, daycares, etc

Question 28

Giardia lamblia transmission

Answer 28

Fecal-oral / contaminated water

Question 29

Giardia lamblia trophozoite structure | **exam question**

Answer 29

2 prominent nuclei Ventral sucking disk 4 pairs of flagella Pear-shaped

Question 30

Which parasite is highly resistant to chlorine, and is therefore associated with swimming pools?

Answer 30

Cryptosporidium parvum

Question 31

Clinical manifestations of Cryptosporidium parvum in immunocompromised patients

Answer 31

Horrific diarrhea -- 50+ stools per day Dehydration This can last for months or years.

Question 32

Which parasite commonly infects AIDS patients?

Answer 32

Cryptosporidium parvum

Question 33

Treatment for Cryptosporidium parvum

Answer 33

No effective therapy | Azithromycin may be used (hit or miss)

Question 34

Which parasite is commonly lethal to AIDS patients?

Answer 34

Cryptosporidium parvum

Question 35

What is significant about Cryptosporidium parvum?

Answer 35

Its oocytes are acid fast | Used to confirm presence in feces

Question 36

What is a kinetoplast?

Answer 36

The DNA-containing mitochondria of Trypanosoma

Question 37

How is Trypanosoma cruzi transmitted?

Answer 37

Reduviid bug -- kissing bug

Question 38

What does Trypanosoma cruzi cause?

Answer 38

Chagas disease

Question 39

How do you become infected by Trypanosoma cruzi?

Answer 39

Kissing bug lands on you, bites and poops on you. You scratch the bite and rub the feces into the wound. This causes inflammation at the site of infection --> Chagoma.

Question 40

What is Romana's sign and what does it signal?

Answer 40

Painless periorbital swelling. Chagas disease caused by Trypanosoma cruzi.

Question 41

Common chronic implication of Trypanosoma cruzi | **exam question**

Answer 41

Dilated cardiomyopathy

Question 42

Trypanosoma cruzi treatment | YNTKT

Answer 42

Nifurtimox

Question 43

How is Trypanosoma brucei transmitted?

Answer 43

Bite by TseTse Fly

Question 44

What is the calling card of Trypanosoma brucei?

Answer 44

Winterbottom's sign --> Enlargement of cervical lymph | Somnolence

Question 45

Trypanosoma brucei treatment

Answer 45

Suramin | Pentimidine

Question 46

Leishmania vector | YNTKT

Answer 46

Sandfly

Question 47

Leishmania treatment | YNTKT

Answer 47

Sodium stibogluconate | Pentamidine

Question 48

Calling card of Leishmania

Answer 48

Disfiguring, ulcerative lesions with necrotic tissue in the middle

Question 49

Cestode characteristics

Answer 49

Segmented (YNTKT) No body cavity or digestive tube Hermaphroditic Oral sucker, botridias, double hooks

Question 50

Trematode characteristics

Answer 50

``` Unsegmented No body cavity Digestive tube ends in cecum Hermaphroditic (except Schistoma) Oral and ventral suckers ```

Question 51

Nematode characteristics

Answer 51

``` Cylindrical Body cavity Digestive tube ends in anus Dioecious Lips, teeth, filariform extremities, dentary plates ```

Question 52

What are the Cestodes?

Answer 52

Taenia and other tapeworms

Question 53

What is a scolex?

Answer 53

Head of a cestode

Question 54

Taenia solium structure | YNTKT

Answer 54

Scolex with 4 suckers and a circle of hooklets

Question 55

Which parasitic infection can lead to megaloblastic anemia?

Answer 55

Diphyllobothrium latum (cestode)

Question 56

What is the most common tapeworm in the U.S.?

Answer 56

Hymenolepsis nana --> only human tapeworm to complete its cycle in one host

Question 57

How is Hymenolepsis nana different from other cestodes?

Answer 57

Both larval and adult forms may be found in man

Question 58

Clinical manifestations of Ancylostoma duodenale (hookworm)

Answer 58

Pot belly Pica Finger clubbing Black stool

Question 59

Ancylostoma duodenale transmission | YNTKT

Answer 59

Larvae can penetrate skin --> associated with walking barefoot NOT INGESTED

Question 60

Parasitic infection caused by walking/running barefoot

Answer 60

Hookworm (Ancylostoma duodenale)

Question 61

Calling card of Enterobius vermicularis infection

Answer 61

Perianal itching

Question 62

What does Trichuris trichiura cause?

Answer 62

Prolapsed rectum in severe cases

Question 63

How is Oncocera volvulus transmitted?

Answer 63

Black fly

Question 64

Oncocera volvulus treatment | YNTKT

Answer 64

Ivermectin

Question 65

Colloquial name for Dracunculus medinensis

Answer 65

Guinea Fire Worm Disease

Question 66

What is the intermediate host for all trematodes? | YNTKT

Answer 66

Snails

Question 67

What is the infective stage of flukes?

Answer 67

Metacercariae