Gastroenteritis Flashcards
1
Q
What is gastroenteritis?
A
- Diarrhoea (+ vomiting)
- Due to enteric infection: viruses, bacteria or parasites
2
Q
Define acute diarrhoea?
A
>=3 episodes of watery stool/day for <14 days
3
Q
Define dysentery?
A
Infectious gastroenteritis with bloody diarrhoea
4
Q
Define persistent diarrhoea?
A
Acutely starting diarrhoea lasting > 14 days
5
Q
Define travellers diarrhoea?
A
Starting during, or shortly after, foreign travel
6
Q
Define food poisoning?
A
Disease cuased by consumption of food/water
7
Q
Common viral causes of gastroenteritis?
A
- Norovirus
- Rotavirus
- Astrovirus
- Adenovirus
- Sapovirus
- CMV
8
Q
Common bacterial causes of gastroenteritis?
A
- Shigella
- Salmonella
- E. coli
- S. aureus
- C. difficle
- C. perfringens
- Campylobacter
- Listeria
- Vibrio cholerae
- Bacillus cereus
9
Q
Parasites which commonly cause gastroenteritis?
A
- Giardia
- Cryptosporidium
- Entamoeba histolytica
- Trichinella
- Trichuriasis
10
Q
Describe Norovirus?
A
- 1d incubation
- Epidemic gastroenteritis
11
Q
Describe Rotavirus?
A
- 1-3d incubation
- Most children affected by 5
- Live vaccine available
12
Q
Describe astrovirus?
A
- 5d incubation
- Less severe than norovirus
13
Q
Describe Adenovirus?
A
- 3-10d incubation
- Enteric adenovirus
- Mainly children
14
Q
describe CMV?
A
- Asymptomatic
- If immunosupressed:
- Colitis, hepatitis, pneumonia
15
Q
Which pathogens cause diarrhoea with and without blood?
A
16
Q
What is a majory cause of traveller’s diarrhoea?
A
Enterotoxigenic E. coli
17
Q
How can traveller’s diarrhoea be prevented?
A
- Boil water
- Cook thoroughly
- Peel fruit and vegetables
18
Q
Presentation of traveller’s diarrhoea?
A
- During first week of travel
- Enterotoxigenic e. coli
- Watery diarrhoea, cramps, nausea
- Giardia lamblia
- Bloating, belching
- Campylobacter and shigella
- Colitic symptoms, cramps
19
Q
Treatment for traveller’s diarrhoea?
A
- Oral rehydration
- Antimotility agents
- Loperamide, bismuth salicylates
- Antibiotics (usually not indicated)
20
Q
Describe a home-made oral rehydration recipe?
A
- 6 teaspoons of sugar
- Half teaspoon of salt
- 1L of clean drinking water
21
Q
Contraindications for antimotility agents?
A
- Severe pain
- Bloody diarrhoea
- ** May indicate invasive colitis
22
Q
Describe Norovirus?
A
- Single-stranded RNA virus
- Transmitted by contact with someone infected, environment or food
- Presents 12-48hrs after exposure, lasts 24-72hrs
- Vomiting, watery diarrhoea, cramps, nausea.
23
Q
Describe the diagnosis and treatment of norovirus?
A
- Diagnosis
- Clinical, stool sample reverse transcriptase PCR
- Treatment
- Supportive
- Anti-motility agents
- Usually self-limiting
24
Q
Describe Rotavirus?
A
- Double stranded RNA, wheel-like appearance
- Most common cause of gastroenteritis in children
- Watery diarrhoea and vomiting, fever, abdo pain
25
Describe the diagnosis and treatment of Rotavirus?
* Diagnosis
* Clinical
* Antigen in stool
* Treatment
* Supportive
* Live vaccine (antigen seen in stool after)
26
Describe Enterotoxigenic E. coli?
* Gram negative anaerobe
* Heat-stable/heat-labile toxin stimulates water efflux into gut lumen
* Watery diarrhoea, cramps
* Important cause of travellers diarrhoea
27
Describe the diagnosis and treatment of Enterotoxigenic e. coli?
* Diagnosis
* Clinical
* Indentification of toxin in stool culture
* Treatment
* Supportive
* Same treatment as traveller's diarrhoea
28
Describe Clostridium perfringens (type A)?
* Gram positive anaerobe
* Produces enterotoxin, spores survive cooking and germinate during unrefridgerated storage
* Sudden-onset diarrhoea, cramps, last \<24 hrs
29
Describe Cholera?
* Gram netative aerobic, coma shaped
* Flagellated so mobile
* Faecally contaminated water
* Types 01 and 0139 cause disease
30
Describe the diagnosis of Cholera?
* Clinical
* Watery, rice-water stool, vomiting, dehydration, metabolic acidosis
* Identification of 01 or 0139 in stool
* Rapid dipstick testing
* Culture
31
Describe the treatment of Cholera?
* Oral rehydration salts
* Requires clean water
* IV fluids if dehydrated
* Ringer's lactate / 0.9% NaCl
* Doxycycline if severe dehydration
* Zinc shortens illness in children
32
Describe the prevention of cholera?
* Clean water
* Oral cholera vaccine
33
Name the types of shigella?
* Boydii
* Sonnei
* Flexneri
* Dysenteriae
34
Describe shigella gastroenteritis?
* Gram negative anaerobe
* Watery/bloody diarrhoea, pain, tenesmus, fever
* Complications: bacteraemia, reactive arthritis, _HUS_
35
Describe the diagnosis and treatment of shigella gastroenteritis?
* Diagnosis
* Stool culture
* PCR/enzyme immunoassay
* Treatment
* Supportive
* Nutrition: green bananas, zinc, vitamin A
* Anitbiotics if systemically unwell
* Avoid antidiarrhoeals =\> toxic dilatation
36
Describe gastroenteritis from enterohaemorrhagic / shiga-toxin producing E. coli (STEC)?
* Gram negative anaerobe
* Produces veratoxins
* Diarrhoea, haemorrhagic colitis, HUS
37
Describe the treatment of STEC?
* Diagnosis
* Stool culture
* PCR/enzyme immunoassay for shiga-toxin
* Treatment
* Supportive
* NO ANTIBIOTICS =\> increased risk of HUS
38
Describe gastroenteritis caused by campylobacter?
* Gram negative, spiral shaped rod
* Bloddy diarrhoea, pain, fever, headache
* Complications: bacteraemia, hepatitis, pancreatitis, miscarriage, Guillain-barre
39
Describe the diagnosis and treatment of campylobacter gastroenteritis?
* Diagnosis
* Stool culture
* PCR/enzyme immunoassay
* Treatment
* Supportive
* Antibiotics only for invasive cases
40
Describe Salmonella enterocolitis?
* Gram negative anaerobe, motile bacilli
* Diarrhoea, cramps, fever
* Invasive infection =\> sepsis, meningitis, osteomyelitis
41
Describe the diagnosis and treatment for salmonella enterocolitis?
* Diagnosis
* Stool culture
* PCR
* Treatment
* Supportive
* Antibiotics only for severe disease
42
Describe Yersinia enterocolitica?
* Gram negative rod
* Diarrhoea, fever, pain (appendicitis mimic)
* Erythema nodosum, reactive arthritis
43
Describe the diagnosis and treatment of Yersinia enterocolitica?
* Diagnosis
* Stool culture
* Agglutination titres
* Treatment
* Antibiotics in severe disease
44
