3.2 - ENTEROBIUS VERMICULARIS

Question 1

other name for E. vermicularis

Answer 1

Oxyuris vermicularis

Question 2

common names

Answer 2

pin worm, society worm, seat worm

Question 3

most common helminth parasite found in crowded and temperate areas

Answer 3

Enterobius vermicularis

Question 4

Final host

Answer 4

man

Question 5

habitat

Answer 5

large intestine (cecum)

Question 6

mode of transmission

Answer 6

ingestion, retroinfection, inhalation, autoinfection

Question 7

infective stage

Answer 7

embryonated egg

Question 8

diagnostic stage

Answer 8

egg, adult worm

Question 9

unique diagnostic feature

Answer 9

• cephalic alae - lateral wings
• esophageal bulb

Question 10

• 2-5 mm
• curved tail and single spicule

Answer 10

male adult

Question 11

• 8-13 mm
• pointed posterior end lays 15,000 eggs

Answer 11

female adult

Question 12

• light yellowish white
• meromyarian muscle arrangement

Answer 12

general morphology

Question 13

• colorless, ovoid with one side flattened
• measures 20-30um wide by 50-60 um long

Answer 13

eggs

Question 14

shape of eggs

Answer 14

D-shaped

Question 15

outer egg layer

Answer 15

albuminous layer
provides mechanical protection

Question 16

inner egg layer

Answer 16

embryonic lipoidal membrane
provides chemical protection

Question 17

eggs can survive ? into the environment

Answer 17

2-3 weeks

Question 18

embryonation of eggs takes ?

Answer 18

4-6 hours

Question 19

life cycle

Answer 19

1. mouth
2. small intestine
3. large intestine
4. copulation (adult male and female)
5. perianal region (deposition of eggs)
6. random objects
7. other members would be in contact, eggs could float
8. accidentally ingest and inhale
9. new host

Question 20

Once someone has ingested pinworm eggs, there is an incubation period of ? or longer for the adult gravid female to mature in the small intestine

Answer 20

1 to 2 months

Question 21

Males usually die after

Answer 21

copulation

Question 22

Females usually die after

Answer 22

egg deposition

Question 23

eggs from the perianal region are accidentally ingested by the same person

Answer 23

Autoinfection

Question 24

when eggs in the perianal region hatch and the larva crawls back up into the intestine or intestinal tract

Answer 24

Retroinfection

Question 25

female adult lays

Answer 25

15,000 eggs

Question 26

Enterobius infection

Answer 26

Enterobiasis or oxyuriasis

Question 27

• nocturnal pruritus ani
• local irritation of the vagina
• inflammation of the intestinal wall
• formation of granuloma
• salpingitis

Answer 27

pathogenesis and clinical manifestations

Question 28

most sensitive diagnostic test

Answer 28

cellulose tape technique

Question 29

clearing agent for cellulose tape technique

Answer 29

toluene

Question 30

when to perform cellulose tape technique?

Answer 30

• late at night
• first thing in the morning before bathing or defecation

Question 31

Adult worms can only deposit eggs ?

Answer 31

late at night

Question 32

? of cases are detected using routine stool examination

Answer 32

5%-10%

Question 33

Before releasing results, it should be conducted on ?

Answer 33

3 consecutive mornings

Question 34

types of perianal swabs

Answer 34

1. National Institute of Health Swab
2. Swellen Grebel Swab
3. Scotch Tape Graham’s
4. Petroleum Coated Swab

Question 35

type of perianal swab that uses cellophane

Answer 35

National Institute of Health Swab

Question 36

type of perianal swab that uses a pestle moistened with water

Answer 36

Swellen Grebel Swab

Question 37

• Common within families with school-aged children, in primary caregivers of infected children, and in institutionalized children
• Only intestinal nematode that cannot be controlled through sanitary disposal of human feces
• Infection through close contact

Answer 37

epidemiology

Question 38

treatment

Answer 38

albendazole