Gastroenteritis

Question 1

def

Answer 1

acute inflammation of lining of GI tract

manifested by nausea, vomiting, diarrhoea, abdominal discomfort

Question 2

aetiology

Answer 2

commonly contaminated food or water
1 viral
-rotavirus, adenovirus, astrovirus
2 bacterial
-campylobacter jejuni, E.coli, salmonella, shigella, vibrio cholerae
3 protozoal
-entamoeba histolytica, cryptosporidium parvum
4 toxins
-s. aureus, clostridium botulinum + perfringens, b. cereus
-botulism (canned foods)

Question 3

what is s. aureus , c. perfringens commonly found in

Answer 3

improperly cooked meat

Question 4

what is b cereus, s. aureus commonly found in

Answer 4

old rice

Question 5

what is salmonella commonly found in

Answer 5

eggs + poultry

Question 6

what is listeria, campylobacter commonly found in

Answer 6

milk + cheese

Question 7

what are the non-inflammatory mechanisms causing gastroenteritis

Answer 7

v. cholerae + enterotoxigenic e. coli
produce enterotoxins
cause enterocytes to secrete water & electrolytes

Question 8

what are the inflammatory mechanisms causing gastroenteritis

Answer 8

shigella + enteroinvasive e. coli
release cytotoxins
invade + damage epithelium

salmonella has greater bacteraemia

Question 9

epi

Answer 9

common

serious cause of morbidity + mortality in developing world

Question 10

history

Answer 10

sudden onset nausea + vomiting
diarrhoea (can be bloody)
abdominal pain
fever

Question 11

what does early onset (1-24h) say about the cause

Answer 11

toxins

Question 12

what does later onset (>12h) say about the cause

Answer 12

bacterial
viral
protozoal

Question 13

what does botulinum toxin cause

Answer 13

paralysis

Question 14

examination

Answer 14

diffuse abdominal tenderness
abdominal distension
increased bowel sounds

Question 15

examination of severe gastroenteritis

Answer 15

pyrexia
dehydration
hypotension

Question 16

investigations

Answer 16

1 bloods
-FBC
-blood culture (for bacteraemia)
-UEs (dehydration)
2 stool
-faecal microscopy for parasites
-electron microscopy for viral
3 AXR/USS
-for exclusion

Question 17

what is pseudomembranous colitis associated with

Answer 17

c. difficile toxin

Question 18

managment

Answer 18

• fluid + electrolyte replacement with oral rehydration therapy (contains glucose + salt)
• antibiotics with severe infection (ciprofloxacin for salmonella, shigella, campylobacter)

Question 19

management for botulism

Answer 19

botulinum antitoxin IM

Question 20

complications

Answer 20

dehydration, electrolyte imbalance, prerenal failure
sepsis (salmonella + shigella)
haemolytic uraemic syndrome from e. coli 0157 toxins
guillian-barre syndrome may occur after recovery from campylobacter gastroenteritis

Question 21

complications of botulism

Answer 21

respiratory muscle weakness or paralysis

Question 22

prognosis

Answer 22

good

most self-limiting