GASTROINTESTINAL Flashcards
What is inflammatory bowel disease
It is inflamed intestines resulting in malabsorption and can present as either crohns disease or ulcerative colitis
Where can crohns disease affect
the whole GIT, from mouth to anus. It especially effects the terminal ileum and the proximal colon
It is non continuous
what HLA type predisposes to IBD
HLA B27 - specifically UC
What are risk factors for developing crohns disease
increased risk with family history
increased risk of you’re jewish
smoking (2X more likely)
NSAIDs
chronic stress
depression
What layers of the intestine does Crohns inflammation affect
Transmural - affects all 4 layers
what are the symptoms of Crohns?
Pain in the right lower quadrant
changes in bowel habit
malabsorption
extraintestinal
what malabsorption conditions can you get with crohns
- B12
- folate
- iron disorders
- gall stones and kidney stones
- watery diarrhoea (no water absorption)
what extraintestinal symptoms can you get with crohns
Aphthous mouth ulcers
uveitis
episceritis
eythema nodosum - rash
pyodema gangrenosum
ankylosing spondylitis
how do you diagnose crohns
pANCA negative (could be positive) - antineutrophil antibodies
Fecal calprotectin positive
Biopsy and endoscopy
Endoscopy
- skip lesions
- cobble stoning
- could have strictures “string sign”
Biopsy
- transmural inflammation with non caseating granulomas
What is the treatment for crohns
- for flares = sulfasalazine and prednisolone
- for remission = azathioprine and methotrexate
- Biologics = Infliximab (anti TNFa) and Usterkenumab (anti IL12 and 23)
- Surgery - not curative
what are complications of crohns
Fistula
Strictures
Abscesses
Small bowel obstructions
where is ulcerative colitis found in the GIT
Only in the colon - starts at the rectum and then moves up to the sigmoid and then proximal colon
is smoking damaging or beneficial in ulcerative colitis
it is protective
What layers of the GIT are affected by UC inflammation
only the mucosa
WHat are the symptoms of ulcerative collitis
pain in left lower quadrant
tenesmus (rectal defecation pain)
bloody mucusy watery diarrhoea
Extraintestinal
What are the extraintestinal symptoms of ulcerative colitis
Uveitis
Episceritis
Pyoderma gangrenosum
Erythema nodosum
Spondylarthopathy - spine ache
primary sclerosing cholangitis
how do you diagnose ulcerative colitis
pANCA positive
Increase in fecal calprotectin
Inflammation seen - CRP/ESR and WCC increase
Malabsorption of iron, Vit B, folate
biopsy - mucosal inflammation with crypt hyperplasia
Colonoscopy - continuous leadpipe sign
How do you determine the severity of ulcerative colitis flares
The TRUELOVE and WITTS score
- mild
- moderate
- severe
what is the treatment for ulcerative colitis
- Flares = Sulfasalazine and prednisolone
- Remission = azathioprine, methotrexate, cyclosporin
- Biologics = Infliximab
- Surgery = total or partial colectomy = curative
what are complications of ulcerative colitis
Toxic megacolon
what is the mode of action of infliximab
it is a monoclonal antibody against TNF-a (pro-inflammatory cytokine)
what is coeliac disease
It is an autoimmune T4 hypersensitivity to gluten
What HLA subtype gives a predisposition to coeliac disease
HLA DQ2 and 8
what is the pathophysiology behind coeliacs disease
The prolamins in gluten (alpha gluten) binds to IgA and interacts with tTG (tissue transglutaminase) which is immunogenic. It results in the formation of increased IgA anti-tTG and endomysial antibodies. This causes destruction of the villi in the gut, causing a villous atrophy, crypt hyperplasia and intraepithelial lymphocytes