diarrhoea Flashcards
what is diarrhoea
increased freq (>3x day) loose or liquid increased vol (>200g/day) change in stool consistency
other conditions to be aware of when diagnosing diarrhoea
faecal incontinence
functional bowel disorders eg IBS
change from normal baseline
acute or chronic diarrhoea
acute is less than 4 weeks mostly infectious and self limiting investigate after a week chronic is more than 4 weeks, chronic pathology always investigate
causes of acute diarrhoea
viral -rota, Nora, enteric adenovirus
bacterial - salmonella, shigella, campylobacter, S aureus
parasitic - C parvum, G lambila, E histolytica
causes of chronic diarrhoea
colonic - ulcerative and Crohn’s, colitis, colorectal cancer
small bowel - coeliac, Crohn’s, bile salt malabs, lac int, bac overgrowth
pancreatic - chronic panc, panc cancer, CF
endocrine - hypothyroidism, diabetes, Addison’s, hormone secreting tumours
other - drugs, alcohol, factitious
mechanisms of diarrhoea
osmotic eg lac int steatorrhoea secretory eg cholera, e coli, gut hormones inflammatory eg UC, chrohn's, infections neoplastic ischaemic post irradiation
investigations for diarrhoea
stool tests (microscopy, culture, faecal elastase and calprotectin) blood tests (eg FBC, CRP, TTG, TFTs, B12) Imaging - colonoscopy, CT, MRI, video capsule
what is the endoscopic appearance of ulcerative colitis
red, inflamed and blistered
endoscopic appearance of Crohn’s disease
linear ulceration
patchy erythema
apthous ulcers
what is ulcerative colitis
continuous mucosal inflammation of the colon
no granulomas
affect rectum and variable extent of colon
relapsing and remitting course
what is Crohn’s disease
discontinuous and often granulomatous
transmural inflammation affecting any part of GI tract
signs of UC
bloody diarrhoea, rectal bleeding, mucus, faecal urgency, abdominal pain, nocturnal defecation
often insidious onset
extra intestinal manifestations
how is UC diagnosed
history and exam
stool cultures + CDT
faecal calprotectin, CRP, FBC, Albumin, flexible colonoscopy
who is UC most common in
any age (mostly young)
relapsing course
smoking inc risk
appendectomy before 20 protective
how is severe UC treated
admit hydrocortisone heparin stool chart AXR daily CRP avoid NSAIDs, opiates, anti-motility agents
how is severe UC treated when it fails to respond to steroids
infliximab
(cyclosporin)
colectomy
how is mild to mod UC treated
mesalazine (oral or topical) prednisolone - reducing course azathioprine biologics - anti TNF, a4B7 integrin blocker, tyrosine kinase inhibitor surgery
what is the prevalence of crohn’s disease
any age (peak in teens/early adulthood) equal in M and F smoking prev appendectomy FH infectious gastroenteritis inc risk
what are the symptom’s of Crohn’s disease
wide spectrum chronic diarrhoea IBS abdo pain WL anaemia growth failure blood +/- mucus in stools perianal disease extra intestinal manifestations
what is Crohn’s disease related to
inflammatory disease
stricturing disease
fistulating disease
perianal disease
how is Crohn’s treated
Prednisolone/Budesonide -corticosteroids
Azathioprine/6-Mercaptopurine - purine analogue
Methotrexate- inhibit folic acid metabolism
nutrition (elemental diet)
ABs
Biologics
surgery
what biologic drugs are used to treat IBDs?
infliximab
adalimumab - anti TNF
vedolizumab - a4B7 integrin blocker
Ustekinumab -IL-12 and IL-23 inhibitor
what is inflammatory bowel disease
UC and Crohn’s disease
