Parasitology - Helminths

Question 1

What type of reproduction do nematodes (round worms) undergo?

Answer 1

sexual

Question 2

What type of reproduction do flat worms (tapeworms, fluke worms) undergo?

Answer 2

asexual

Question 3

What causes whip-worm disease?

Answer 3

Trichuris trichiura

Question 4

Explain life cycle of trichuris trichiura.

Answer 4

• ingest larval egg
• larva hatch in small intestine
• migrate into colon (1-3 mo. to mature)
• worm digs head into intestinal mucosa to feed
• impregnated egg excreted with stool

Question 5

Symptoms of whipworm disease?

Answer 5

• usually asymptomatic
• stomach ache
• diarrhea
• appendicitis can happen

Question 6

Treatment for whip worm disease (Trichuris trichiura)?

Answer 6

• Mebendazole

- albendazole

Question 7

What is the pathogeny of helminths?

Answer 7

obligate pathogens

(must cause disease to be transmitted from one host to another)

Question 8

Diagnosis of whip worm disease?

Answer 8

• sample stool, detection of eggs

Question 9

What is the mode of transmission of ascaris lumbricoides?

Answer 9

• fecal-oral transmission

- -> typically contaminated food

Question 10

Symptoms of ascaris?

Answer 10

• weight loss
• malnutrition
• obstruction at ileocecal valve or biliary obstruction

Question 11

Life cycle of ascaris?

Answer 11

• ingest eggs
• larvae emerge in small intestine
• larvae penetrate intestines, go into blood stream, travel to lungs
• grow in alveoli
• cough up, swallow back into intestines
• mature into adult worms

Question 12

Diagnosis of ascaris lumbricoides?

Answer 12

• sample stool: eggs in stool

- high eosinophil count in blood smear (b/c of tissue invasion, eosinophils increase)

Question 13

Treatment for ascaris lumbricoides?

Answer 13

• mebendazole (intestinal stage)

- thiabendazole (migrating stage)

Question 14

Life cycle of enterobius vermicularis?

Answer 14

• ingest eggs
• hatch in duodenum
• mature in colon
• female lays eggs in perianal folds

Question 15

What causes pinworm disease?

Answer 15

Enterobius vermicularis

Question 16

Symptoms of pinworm disease (enterobius vermicularis)?

Answer 16

-perianal itching at night
(anal pruritis)
-neurotic complaints, appendicitis

Question 17

Diagnosis of pinworm disease?

Answer 17

• adhesive tape at perianal area

- anal swab

Question 18

Treatment of pinworm disease?

Answer 18

• mebendazole

- albendazole

Question 19

How is trichinella spiralis transmitted?

Answer 19

• undercooked meat (often pork, or wild game)

- possibly fecal-oral

Question 20

What does trichinella spiralis cause?

Answer 20

Trichinellosis

Question 21

Symptoms of trichinosis (trichinella spiralis)?

Answer 21

• fever
• vomiting
• nausea
• periorbital edema
• myalgia

Question 22

Diagnosis of trichinella spiralis?

Answer 22

-muscle biopsy: larva detection

Question 23

What type of worm is the trematode class?

Answer 23

Fluke worm

Question 24

What type of worm is the cestode class?

Answer 24

Tape worm

Question 25

What type of worm is a nematode?

Answer 25

Round worm

Question 26

What does the taenia species cause?

Answer 26

- cysticercosis (T.solium) | - taeniasis

Question 27

How do you treat cysticercosis?

Answer 27

praziquantel

Question 28

How do you contract cysticercosis? (T. solium)

Answer 28

Ingesting eggs that are in food contaminated with human faces

Question 29

Where do larvae encyst in cysticercosis (Taenia solium)?

Answer 29

- brain | - skeletal muscle

Question 30

If cystercici reach the brain, what does it cause?

Answer 30

Neurocysticercosis

Question 31

How does taenia solium progress in the body?

Answer 31

- if you ingest the eggs, the larva dig into gut wall - migrate into muscles by blood circulation - encyst in muscle and brain - cause cysticercus

Question 32

How can you diagnose cysticercosis?

Answer 32

Tissue biopsy

Question 33

How do you detect taeniasis?

Answer 33

Detection of proglottids in stool

Question 34

What does echinococcus granulosus cause ?

Answer 34

Hydatid cysts in liver

Question 35

How is taeniasis contracted?

Answer 35

Ingestion of taenia cysts and/or larvae

Question 36

How is cysticercosis contracted?

Answer 36

Ingestion of eggs in fees contaminated water

Question 37

What disease occurs if you ingest taenia cysts and/or larvae?

Answer 37

Taeniasis

Question 38

What disease occurs if you ingest taenia eggs in feces contaminated water?

Answer 38

Cysticercosis | --> if reaches brain, causes neurocysticercosis

Question 39

What does fasciolopsis buski cause?

Answer 39

Gut fluke disease

Question 40

What is gut fluke disease caused by?

Answer 40

Fasciolopsis buski | trematode, ie fluke worm

Question 41

What is/are the a) definitive host b) intermediate host of gut fluke disease?

Answer 41

a) D. host = human | b) I. host = swine, dog, rabbit

Question 42

Symptoms of gut fluke disease (fasciolopsis buski)?

Answer 42

- diarrhea - stomach cramps - mucosal exulcerations

Question 43

Treatment for gut fluke disease?

Answer 43

Praziquantel

Question 44

What disease does wuchereria bancrofti cause?

Answer 44

Elephantiasis

Question 45

What is elephantiasis caused by?

Answer 45

Wuchereria bancrofti

Question 46

How is wuchereria bancrofti transmitted?

Answer 46

via mosquitos: - female anopheles - aedes - culex

Question 47

What type of parasite is wuchereria bancrofti?

Answer 47

Tissue nematode

Question 48

Symptoms of wuchereria bancrofti?

Answer 48

- lymphangitis (inflammation of lymph vessels) - fever - lymphadenitis (swelling of >1 lymph node) - cellulitis

Question 49

Treatment for elephantiasis?

Answer 49

- Diethylcarbamazine | - Mebendazole

Question 50

What is the host of schistosoma species?

Answer 50

Fresh water snails

Question 51

What are the 3-phase disease symptoms of schistosomiasis?

Answer 51

1) Dermatitis - allergic inflamm., erythema, itching (as cercariae penetrate skin) 2) Katayama syndrome - fever, chills, hives, splenomegaly (as eggs laid in venous system) 3) Chronic fibrosis - fibrosis in organs and vessels (as the body tries to wall off the eggs that are on the organs and vessels)

Question 52

In chronic inflammation, what causes urinary bladder cancer?

Answer 52

Schistosoma haematobium | invades venous system of urinary bladder

Question 53

Treatment for schistosomas?

Answer 53

Praziquantel

Question 54

Life cycle of schistosoma spp.?

Answer 54

-eggs hatch in fresh water -find freshwater snails and mature -mature larvae (cercariae) released by snail into water, & are freely-swimming -penetrate human swimmer's skin -migrate to portal blood and mature into adults -some adults migrate to bowel/rectum (eggs circulate to liver and/or shed in stools)