GI and Liver Flashcards
what are some broad causes of IBD
environmental factors
genetic predisposition
gut microbiota
host immune response (innate/adaptive)
common presentation of infective colitis
- short history of diarrhoea that can be accompanied by vomiting
- abrupt onset
- systemic upset and fevers
- recent travel
- unwell contacts
- immunocompromised
what investigations would you perform if you suspected infective colitis
stool Cx/CDT
you require 4 for 90% sensitivity
what is the treatment for infective colitis
conservative treatment if patient is immunocompromised but symptoms should resolve on their own
What is the presentation of ischaemic colitis
indicated in patients that are elderly, with CV disease and heart failure
- abrupt onset with bloody diarrhoea with or without systemic inflammatory response syndrome (tachycardia, hypotension, tachypnoea, and occasionally raised temperature without an infective focus)
- CT may show segmental colitis in watershed areas (SPLENIC FLEXURE)
treatment for ischaemic colitis
conservative (IV fluids with or without antibitocs
When would you admit a patient with diarrhoea
if they had stools more than 6 times a day combined with systemic upset
what initial investigations would you perform if a patient was admitted to hospital with diarrhoea
abdominal xray - helps to assess disease extent and severity
stool cultures
endoscopy - flexible sigmoidoscopy or colonoscopy
CT Scan
what are the parameters to diagnose toxic megacolon
more than 5.5 cm or a caecum of more than 9
how can you diagnose toxic megacolon
if there is a megacolon on xray accompanied with signs of systemic toxicity and requires emergent colectomy
what are the four layers of the bowel
mucosa
sub mucosa
muscular mucosa
sub serosa
acute changes which occur in chronic inflammatory bowel disease
- acute inflammation
- ulceration
- loss of goblet cells
- crypt abscess formation
MEDIATED BY NEUTROPHILS
Chronic changes in chronic inflammatory bowel disease
- architectural changes
- panted cell metaplasia
- chronic inflammatory infiltrates in the lamina propria - more lymphocytes and plasma cells
- neuronal hyperplasia
- fibrosis
what are some macroscopic features of UC
there is predominantly diffuse involvement of the lower GIT
terminal ileum is only involved in severe illness where the whole bowel is involved inlcluding the caecum (back wash ileitis)
what are some macroscopic features of UC
there is predominantly diffuse involvement of the lower GIT
terminal ileum is only involved in severe illness where the whole bowel is involved inlcluding the caecum (back wash ileitis)
what re some microscopic features of UC
- crypt architectural changes are generally very marked
- little/no fibrosis
- no granulomas
what is the usual treatment for UC
5-ASA/Mesalazine best to be combined with topical as this has better effectiveness if the UC was effecting far down the bowel towards the rectum
escalated:
- azathioprine = used in severe relapse/frequently relapsing disease RISK OF LYMPHOMA, NMSC and Ca
- biologics/surgery
what is the treatment for ASUC - acute severe ulcerative colitis
high-dose intravenous corticosteroids such as methylprednisolone 60mg daily or hydrocortisone 100mg - 6 hourly
also should receive prophylactic low-molecular weight heparin
what is the indication that a patient who has been admitted with ASUC needs a colectomy
if after treatment, on day three they still have a stool frequency of over 8 stools a day OR more than three plus a CRP of over 45
85 %
TO PREVENT THIS
considerr infliximab or ciclosporin or surgery
iinfliximab
monoclonal antibody to TNF-alpha
complications of UC
local:
haemorrhage
toxic dilation
systemic:
- skin = erythema nodosum
- liver = sclerosing cholangitis and cholangiocarcinoma
- eyes = iritis, uveitis and episcleritis
- ankylosing spondylitis
MALIGNANCY - 1 3 or 5 year screening
crohns disease class. presentation
x2 more likely in smokers - stopping reduces relapse, reduces the needs for immunosuppression and surgery (PEAK INCIDENCE AT 15-25)
- abdominal pain (central indicating the small bowel)
- diarrhoea (more watery than bloody)
- weight loss
- fistulae, abscesses, oropharyngeal, gastroduodenal
crohns disease class. presentation
x2 more likely in smokers - stopping reduces relapse, reduces the needs for immunosuppression and surgery (PEAK INCIDENCE AT 15-25)
- abdominal pain (central indicating the small bowel)
- diarrhoea (more watery than bloody)
- weight loss
- fistulae, abscesses, oropharyngeal, gastroduodenal
what is faecal calprotectin
calcium binding protein which is predominantly derived from neutrophils
- normal is less than 50
good to differentiate between IBS and IBD
