Gastroenteritis Flashcards
1
Q
What are common causes of diarrhoea?
A
- Bacterial: samlonella, E.Coli, campylobacter, C.Diff, staph aureus
- Non infective
- Viral: Noro/rotavirus
- Parasitic: cryptosporidium, Giardia lamblia, Entamoeba
2
Q
Describe viral gastroenteritis
A
- Norovirus
- Diarrhoea & projectile vomiting
- 24-48hrs
- Aerosol transmission= low infective dose
3
Q
What parasites can cause parasitic gastroenteritis?
A
- Cryptosporidium
- Giardia
- Entamoeba
4
Q
Describe cryptosporidium infection
A
- Cryptospordiosis mainly waterborne disease (contaminated water)
- Oocyst resistant to chlorine based disinfectant
- Watery diarrhoea
- Mild to severe mainly children affected
- 2nd half of the year though to be caused by C.hominis
5
Q
In bacterial gastroenteritis what pathogens produce enterotoxins?
A
- Vibrio cholerae
- E.Coli
- Clostridium perfringens
- Staph aureus
- Bacillus cereus
- C.Diff
6
Q
In bacterial gastroenteritis what pathogens produce adherence?
A
- Shigella sonnei/flexneri
- E.Coli
- Salmonella
- Campylobacter jejuni
7
Q
What is E.Coli’s mechanism of action?
A
- Similar to cholera
- Toxin activates G protein leading to inc levels of cAMP
- Activates ion channels- overexcretes ions
- Water follows out of cell into bowel
- Efflux of K or Cl ions meaning water loss by osmosis
8
Q
How is gastroenteritis treated?
A
-Supportive
-No antibiotics
Except: V. young/old, campylobacter-prolonged/severe symptoms, invasion
9
Q
What antibiotics are associated with a high & medium risk of C.Diff infection?
A
- High: Cephalosporins, Clindamycin
- Medium: Macrolides, fluoroquinolones, co-trimoxazole, ampicillin/amoxicillin
