Gastro-enteritis Flashcards
What is THE most common causative organism of diarrhoea in out country?
Campylobacter
What are the 2nd and third most common causes of gastroenteritis?
Salmonella
E.coli 0157
What is the most common cause of travel-related gastroenteritis?
E.coli 0157
How is campylobacter transmitted?
Contaminated food
How salmonella most commonly acquired?
Contaminated food in foreign countries
How is norovirus transmitted?
Person to person spread
What are the 4 factors that provide the host with defences?
Hygiene
Stomach acidity
Normal flora
Immunity
What are the 3 types of diarrhoea?
Non-inflammatory = secretory toxin causing frequent watery stool and abdominal pain
Inflammatory - toxin damage and mucosal destruction causing pain and fever
Mixed picture eg C.diif
What is cholera’s mode of action of causing diarrhoea?
Increases cAMP levels and Cl- secretion and therefore pulls the water into the lumen
Which bacteria causes an inflammatory response?
Shigella
What are the 3 mechanisms of diarrhoea?
Toxin-mediated
Invasion
Attachment
What are 3 parasites that can cause diarrhoea?
Cryptosporidium parvum
Giardia Intestinalis
What are the clinical features of a Salmonella infection?
48hr post-exposure
Lasts for 10 days
Don’t give antibiotics
What are the clinical features of a campylobacter infection?
Incubation up to 7 days
Clears within 3 weeks
Severe abdominal pain
What are the clinical features of a E.coli infection?
Increasing incidence
Excretion >3wks post symtoms
5-9 days later can develop HUS because it produces a toxin which can enter the bloodstream
What organism is involved in antibiotic related diarrhoea?
C.difficile
what 4 C antibiotics are associated with C.Diff?
Clarithromycin,
Co-amoxiclav
Clindamycin
Cephalosporin
What is the diagnostic criteria of gastroenteritis?
Three or more loose stools a day for less than 2 weeks with the following accompanying features: Pain Fever Blood or mucus in the stool Vomiting
What are your key investigations?
Stool culture Blood culture - salmonella U&E FBC: neutrophilic, haemolysis Sigmoiscopy
What things are you looking for on your examination
BP and postural hypotension Skin turgor Pulse Inflammation markers - fever Mainly fluid hydration status
If you suspect a parasite then what investigations are you going to do?
Microscopy
If it is confirmed as non-inflammatory diarrhoea then what is your management?
Rehydration with either oral salt and sugar solution
IV saline
What are the indicators for use of antibiotic in diarrhoea?
Traveller's diarrhoea Immunocompromised Severe sepsis Chronic illness DM Valvular hear disease
How can you treat a C.diff diarrhoea?
STOP the causative antibiotics
Oral metronidazole instead and if segvere then Vancomycin
Give34 differential of Gastro-enteritis
IBD - over 2 weeks
Overflow diarrhoea - contipated
Sepsis outside the GI tract - they have no blood/mucus
What is haemolytic uraemia syndrome?
Microangiopathic Haemolytic Anaemia
Thrombocytopenia
AKI
Result of E.coli infection
