Gastroenteritis Flashcards
E. coli
Commonest among travellers
Watery stools
Abdominal cramps and vomiting
Giardiasis
Prolonged, non-bloody diarrhoea
Travel to developing countries; ?contaminated water
Cholera
Profuse, watery diarrhoea
Severe dehydration –> weight loss
Not common in travellers
Contaminated water in Africa
Shigella
Bloody diarrhoea
Vomiting + Abdominal Pain
Staph Aureus
Severe vomiting
Found in cream - exotoxin –> Short incubation period
Campylobacter
'flu-like prodrome followed by: - Crampy abdominal pain - Fever - Diarrhoea +/- blood Complication: Guillain Barre
Bacillus Cereus
Two types:
- Vomiting in less than 6 hours from rice
- Diarrhoea after 6 hours
Amoebiasis
Gradual onset Bloody Diarrhoea Abdominal pain + tenderness May last a few weeks Liver abscess; Rx metronidazole
Which organisms have an incubation period of 1-6 hours?
Staph aureus + Bacillus cereus
Due to Preformed Toxin
Which organisms have an incubation period of 12-48 hours?
Salmonella + E. coli
Which organisms have an incubation period of 48-72 hours?
Shigella + Campylobacter
Which organisms have an incubation period of > 7 days?
Giardiasis
Amoebiasis
Which organisms have an incubation period of 1-9 days?
Cholera
What is the general guideline behind treating gastroenteritis`
Supportive: (iv/oral) fluid rehydration
If bloody and systemic upset may warrant treatment
How do you treat Campylobacter if systemic features?
Erythromycin or Ciprofloxacin
How do you treat Salmonella (if systemic features)?
Ciprofloxacin
How do you treat Giardiasis?
PO Metronidazole
How do you treat Enterebius vermicularis?
PO mebendazole
Clostridium perfringes
Normal gut flora but spores
Preformed toxin
Salmonella typhi/paratyphi
Poor sanitation, water, food
Fever, ‘Rose spots’ + diarrhoea
14-21 days incubation
How do you treat salmonella typhi/paratyphi?
Ceftriaxone OR Azithromycin OR Ciprofloxacin
Helminth infections are often associate with?
Eosinophlia
How are helminth infections diagnosed?
Adult worm or eggs passed in stool
What are the most common intestinal nematodes?
Ascariasis
What is the mechanism of intestinal nematode?
Invade tracheoalveolar tree, swallowed and then invade gut and produce eggs
What are examples of trematodes (flukes)?
Schistosomiasis (fresh water exposure - acute/chronic infection) Liver flukes (Clonorchis/Fasciola) - SE Asia
What are examples of cestodes (tapeworms)?
Taenia Solium (pork) or saginatum (beef) - acquired from undercooked meat containing infectious larval cysts Taenia salium (autoinoculated or from human faeces) can cause cysticerlosis - tissue cysts in muscle and brain)
What is Chagas Disease?
Transmitted by the kissing bug (triatomic)
Causes parasympathetic denervation affecting the colon or oesophagus
Megaoesophagus
