Gastroenteritis Flashcards
bacilus cereus
1-6 hours incubation lasts 24 hours reheating starchy foods - rice profuse vomiting due to heat resistant spores gram +ve bacilus
staph aureus
1-6 hours incubation preformed toxin causing rapid absorption lasts 1-2 days food left at room temperature milk, meat, fish vomiting abdominal pain
campylobacter
16-48 hours incubation lasts 2-20 days raw poultry, raw milk D&V may be bloody abdomen pain, fever risk of Guillain Barre syndrome
salmonella
outbreaks 12-48 hours lasts 2-7 days poultry meat, raw egg, raw milk transmitted from reptiles D&V unlikely to be bloody abdomen pain, fever serotyped according to o antigen
shigella
1-7 days incubation lasts 2-7 days contaminated food and water bloody diarrhoea/mucous and vomiting abdominal cramps, fever
shigella toxin
toxin binds to receptors on renal cells, RBCs and other cells
toxin inhibits protein synthesis
toxin type 2 is more potent than type 1
E.coli 0157
1-14 days incubation lasts 5-10 days rare, outbreaks cattle/beef, raw milk bloody diarrhoea, may have vomiting abdomen pain often no fever risk of HUS don't give antibiotics very low infectious dose must notify health protection unit
verotoxin
shiga like toxin
binds to enterocytes causing inhibition of protein synthesis
enterocyte dies providing a route into the blood stream
death of vascular endothelial cells
clots form in small vessels
clots and verotoxin travel to kidneys eventually renal failure
bloody urine, low urine output
resulting in HUS
HUS
haemolytic uraemic syndrome
antibiotics, antimotility and NSAIDs may precipitate HUS
abdomen pain, fever, pallor, petechiae (purple spots), oliguria (small urine output)
HUS management
investigations bloody stool test FBC, U&Es, LFT, urine samples lactate dehydrogenase - released from damaged cells must notify relevant health board supportive treatment
listeria
3-70 days incubation
lasts weeks
pregnant women, immunocompromised at risk
soft cheese, deli meats, unpasteurised milk
fever, stiff neck, confusion, vomiting
sometimes preceded by diarrhoea
c.diff
after hospital antibiotics
toxin A (enterotoxin) and toxin B (cytotoxin)
watery diarrhoea
may progress to pseudomembranous colitis or bowel perforation
abdomen pain and fever
c.diff treatment
non severe - metronidazole
severe - vancomycin and metrnidazole
rotavirus
48 hours incubation lasts a week usually children <3yrs most common cause of diarrhoea in kids <3 mild watery or profuse diarrhoea can b severe in immunocompromised child not bloody can cause malabsorption
norovirus
24-48 hours incubation lasts 1-3 days cruise ships, wards and nursing homes, shellfish highly infectious explosive D&V not bloody
stool culture
salmonella
campylobacter
stool toxin
E.coli
c.diff
shigella
staph aureus
stool PCR
norovirus
rotavirus
stool microscopy
parasitic infection
treatment
don’t give antibiotics except c.diff
rehydration is key
acute traveller’s diarrhoea
3 loose stools in 24hrs on the back of travelling
1/3rd of people have associated fever
usual causative organism is enterotoxigenic e.coli
acute traveller’s diarrhoea management
stool culture
rehydration
if travelling a single dose of a ciprofloxacin can be given
cholera
gram -ve bacilus usually from drinking faeces contaminated water profuse watery diarrhoea rice water stools toxin mediated
enteric fever
fever, headache and abdominal discomfort
GI bleeding and perforation
typhoid caused by salmonella typhi
paratyphoid caused by s.paratyphi - less severe
SE Asia, Indian subcontinent
