Inflammatory Bowel Disease Flashcards
describe the external longitudinal muscle of the large intestine
incomplete
- three distinct bands: teniae coli
- haustra are sacculations caused by contraction of teniae coli
what is IBD
group of conditions characterised by idiopathic inflammation of the GI tract, affecting the function of the gut
what are the 2 most common types of IBD
crohn’s disease
ulcerative colitis (young adults)
give an overview of ulcerative colitis
- Begins in rectum, can extend to involve entire colon
- Continuous pattern
- Mucosal inflammation (not transmural)
what are systemic complications of IBD
- extra-intestinal: MSK pain (up to 50%), arthritis
- skin (up to 30%): erythema nodosum, pyoderma gangrenosum, psoriasis
- liver/biliary tree: primary sclerosing cholangitis
- eye: uveitis
what are causes of IBD
Genetic:
-1st degree relative increased risk
-Identical twins concordance 70%
Gut organisms
Immune response –>triggers –> antibiotics, infections, smoking, diet
how might a Crohn’s patient present
- Loose stool - non bloody
- Weight loss due to decreased nutrient absorption
- RLQ pain (position of ileum)
- Smoker
what are the examination findings of Crohn’s
- Tender mass (RLQ)
- Mild perianal inflammation/ulceration
- Low grade fever
- Mildly anaemic (blood loss due to perforation of ulcers)
what are the gross pathological features of Crohn’s
- Cobblestone appearence
- Skip lesions
- Hyperaemia (red)
- Mucosal oedema
- Discrete superficial ulcers
- Deeper ulcers
- Transmural inflammation which leads to thickening of bowel wall and narrowing of lumen
- Can lead to formation of fistulae between bowel and bladder/vagina/skin
what are the microscopic features of crohn’s
granuloma formation (pathognomonic): organised collection of epithelioid macrophages
how is Crohn’s investigated
- Bloods - anaemia
-
CT/MRI scans:
-bowel wall thickening
-obstruction
-extramural problems - Barium enema - locates strictures and fistulae
- Gross pathological changes visible during endoscopy
- skip lesions
- cobblestone
- fistulae
- strictures
what are the different types of UC
how might a patient with UC present
Passing MANY loose stools - bloody
-mucus in stools
Weight loss
Mild lower abdominal pain
Painful red eye
what might be found on examination of suspected UC patient
Mildly tender abdomen
No perianal disease - UC is only a superficial process
Normal temp
what gross pathological changes are seen in UC (2)
Pseudopolyps can develop after repeated episodes:
-Inflammation then healing
-Non neoplastic
-More common in UC (vs Crohn’s)
Loss of haustra - haustra are suculations formed by contraction of outer longitudinal muscle (teniae coli)
what microscopic pathological changes can be seen in UC
- Chronic inflammatory infiltrate of lamina propria
- Crypt abscesses (neutrophilic exudate in crypts)
Crypt distortion:
- Irregular shaped glands with dysplasia
- Darker crowded nuclei
- Reduced numbers of goblet cells
compare distinguishing characteristics of crohn’s and ulcerative colitis
compare the pathological features of UC and crohn’s disease
compare endoscopic changes seen in UC and crohn’s disease
what feature of crohn’s can be seen in barium follow through
long strictures known as string sign of kantour
give 5 defining features of crohn’s
give an overview of Crohn’s disease
- Affects anywhere in the GI tract
- Ileum involved in most cases
- Transmural (affects whole thickness of GI wall)
- Skip lesions (parts of inflammation separated by normal tissue)
