Diarrhoea Flashcards
Define Diarrhoea
> 200g stool/24hrs
OR
3+ stools/day + loose
acute <2 weeks
chronic >4 weeks
How much fluid is secreted in the GI tract? How much is absorbed?
9L in (saliva, intestine, bile, pancreas, gastric, diet) 0.1L out (small bowel, large bowel)
What is ORS made up of?
1L water 3.5g NaCl 2.5g NaCO3 1.5g KCl2 20g glucose
What are the most common causes of acute diarrhoea?
virus - rota/adeno/noravirus
bacteria - Campylobacter jejuni, then E.Coli, salmonella, shigella
parasitic - Giardia lamblia is most common, Entamoeba histolytica, Cryptosporidium spp
non-infectious - food intolerances, IBD, drugs, alcohol
How can you differentiate between pancreatic and SB steatorrhoea?
Pancreatic: normal RBC folate faecal fat >20g/24hrs faecal elastase ERCP + normal imaging
Small Bowel: low RBC folate Anti-TTG antibodies Bx CT/MRE
List some drugs which can cause diarrhoea
alcohol abx anti-depressants NSAIDs anti-hypertensives statins GI drugs biguanides
What is Osmotic Diarrhoea?
= a high concentration of solute in bowel
drags water back into the lumen
eg high salt/sugar, malabsorption
What is Secretory Diarrhoea?
= an increase in the active secretion or there is an inhibition of absorption
little to no structural damage
eg enterotoxins from E.Coli
What are the types of diarrhoea?
Osmotic Secretory Motility Inflammatory Exudative = blood in the stool
What is FODMAP?
fermentable oligosaccharides dissacharides monosaccharides and polyols
What is Clostridium Difficile?
anaerobic gram -ve spore-forming bacteria faecal-oral route toxins A & B most common in elderly, IBD --> life-threatening
What defines the severity of C.Difficile and how is it managed?
mild - 3 stools/24hrs, normal WCC - PO Metronidazole
moderate - 3-5 stools, <20 WCC - PO M
severe - >20 WCC, >38.5 temp, raised CRP, abdo pain - PO vancomycin
complicated - hypotensive, partial ileus, severe disease on CT - PO vancomycin + IV metronidazole
life-threatening - complete ileus or TMC - PO vancomycin + IV metronidazole + faecal transplant (potential colectomy)