microbiology Flashcards
what is gastroenteritis?
acute GI infection of the bowels causing diarrhoea
what are the general mechanisms bacteria use in gastroenteritis?
mucosal adherance
mucosal invasion
toxin production of enterotoxins or cytotoxins
what do enterotoxins in gastroenteritis cause?
fluid secretion without mucosal damage resulting in profuse watery diarrhoea
what do cytotoxins in gastroenteritis cause?
damage to the mucosa of the gut resulting in dysentery
what is dysentery?
diarrhoea with blood and mucus in it due to gut mucosa damage
what are the two broad categories of symptoms of bacterial gastroenteritis?
watery diarrhoea
dysentery
how do enterotoxins get into humans?
by being produced by the bacteria once it has entered the gut OR by ingesting pre-formed enterotoxins present on food
which types of bacteria can cause both watery diarrhoea and dysentery?
salmonella
campylobacter
c difficile
what is traveller’s diarrhoea and what are the common causes? List 4
> 3 non-formed stools/day
enterotoxigenic E. coli, shigella spp, salmonella, campylobacter
what is the general management of bacterial gastroenteritis?
Supportive as usually passes after a few days
might need antibiotics if severe or immunocompromised
what is the most common cause of bacterial gastroenteritis?
salmonella
