14.1

Question 1

nematodes are

Answer 1

roundworms

common worldwide

Question 2

most infections with nematodes occur in

Answer 2

conditions of poor sanitation

in australia - most commonly in returned travellers, immigrants, refugees, impoverished people, children

Question 3

roundworms contracted by

Answer 3

faecal oral transmission

ingestion of eggs - fecal contamination of fomites, soil, food

Question 4

ascaris lumbricoides

Answer 4

largest human parasite
eggs hatch in small intestine
penetrate mucosa to access venous circulation, migrate tot the lungs
larvae migrate to the trachea and are swallowed
develop into adults in small intestine
eggs shed into small intestine
infections usually asymptomatic
heavy worm burdens may cause intestinal obstruction, malnutrition and impaired growth in children

Question 5

enterobius vermicularis

Answer 5

pinworm and threadworm
very common paediatric parasitic infection worldwide
adult worms inhabit caecum, colon, appendix
female lays ova on perianal skin
causes pruritis ani (itchy anus) especially in children

Question 6

transmission of enterobius vermicularis

Answer 6

direct contact with mouth from contaminated fingers or fomites

Question 7

ova of enterobius vermicularis

Answer 7

characteristic, delicate football shaped ova

Question 8

eggs of enterobius vermicularis are demonstrated by

Answer 8

cellulose tape test

Question 9

trichuris trichiura

Answer 9

whipworm

adult worms inhabit large intestine

Question 10

trichuris trichiura seen in

Answer 10

mainly seen in tropics and sub-tropics in areas of poor sanitation and contaminated soil

Question 11

trichuris trichiura life cycle

Answer 11

adult worms inhabit large intestine 
thin, whip like anterior end (head) burrows into intestinal mucosa 
thicker end (tail) contains reproductive tract extends into the intestinal human 
ova shed into lumen, passed in feaces into soil 
ova embryonate in the soil after 2-4 weeks become infectious

Question 12

trichuris trichina tranmission

Answer 12

ingestion of embryonate eggs

Question 13

trichuris trichiura diagnosis

Answer 13

microscopy, demonstration of ova in faeces

characteristic lemon shaped tea tray ova

Question 14

adult worms of trichuris trichiura

Answer 14

adult worms rarely seen in faeces - may be seen on colonoscopy

Question 15

light infection with trichuris trichiura

Answer 15

usually asymptomatic

Question 16

heavy infections with trichuris trichiura

Answer 16

may cause abdominal pain, vomiting, anorexia, weight loss

in children may cause anaemia and growth retardation

Question 17

common parasite of children in developed countries

Answer 17

enterobius

Question 18

parasitic nematode infections are usually diagnosed by

Answer 18

light microscopy of concentrated stool specimens, when the clinician requests a formal examination for ova, cysts and parasites

Question 19

cellulose tape examination is used for

Answer 19

enterobius infection diagnosis

Question 20

whipworm is

Answer 20

trichuris

Question 21

pinworm/threadworm is

Answer 21

enterobius

Question 22

identification of gut nematodes is based on

Answer 22

morphology of the ova

Question 23

gut nematodes are acquired through

Answer 23

feacal oral route or contaminated fomites