Protozoal gastroenteritis

Question 1

What are the most common causes of protozoal gastroenteritis? (3)

Answer 1

1. giardia lamblia
2. cryptosporidium parvum
3. entamoeba histolytica

Question 2

Who gets entamoeba histolytica infections in developed countries?

Answer 2

1. migrants from endemic areas

2. travellers to endemic areas

Question 3

What forms does entamoeba histolytica exist in?

Answer 3

1. cyst

2. trophozoite

Question 4

What is a complication of entamouba histolytica infection?

Answer 4

trophozoites can ascend portal venous system and cause liver abscesses

Question 5

What is the onset of amoebic dysentry?

Answer 5

subacute onset 1-3 weeks

Question 6

What are the symptoms of amoebic dysentry? (4)

Answer 6

1. diarrhoea - bloody
2. abdominal pain
3. weight loss
4. fever

Question 7

How is amoebic dysentry diagnosed?

Answer 7

1. stool microscopy
2. antigen detection
3. serology

Question 8

How is stool microscopy done in the case of amoebic dysentry? (2)

Answer 8

1. detection of cysts or trophozoites

2. 3 samples from separate days

Question 9

What is the problem with using serology to diagnose amoebic dysentry?

Answer 9

positive serology will not distinguish between acute and past infection

Question 10

Who are amoebic liver abscesses seen in?

Answer 10

8-20 weeks after a traveller returns

Question 11

What are the symptoms of amoebic liver abscess? (4)

Answer 11

1. right upper quadrant pain - may radiate
2. fever
3. diarrhoea
4. hepatomegaly

Question 12

How is amoebic liver abscess diagnosed?

Answer 12

1. imaging
2. serology
3. aspirate microscopy

Question 13

How is imagine used to diagnose amoebic liver abscess?

Answer 13

1. ultrasound , CT, MRI
2. 70-80% solitary lesions
3. usually in right lobe of liver

Question 14

how is amoebiasis treated?

Answer 14

1. oral metronidazole

2. paromomycin to eradicate intraluminal cysts