Pathology of Colon Flashcards
(50 cards)
What bowel has the presence of innumerable villi
Small intestine
What are the cryptic and cells present in the large intestine
Tubular crypts
Surface-columnar absorptive cells
Crypts -goblet cells
endocrine cells
How often is the stem cell turnover in the large intestine
3-8days
What is the neural control of the small and large intestine
Both the small and large bowel peristalsis is mediated by intrinsic (myenteric plexus) and extrinsic (autonomic innervation)
What are the two myenteric plexus and where are they located
Meissener’s plexus: base of the submucosa
Auerbach plexus: between the inner circular and outer longitudinal layers of the muscularis propria
What is the definition of inflammatory bowel disease
Chronic inflammatory conditions resulting from inappropriate and persistent activation of the mucosal immune system driven by the presence of normal intraluminal flora
What are the two main and other diseases of IBD
Crohns disease
Ulcerative disease
also
- ischaemic colitis
- radiation colitis
- Appendicitis
What is the differences between Crohns disease and ulcerative colitis
CD - affect any part of the GI tract where UC is limited to the colon
An NOD2 gee mutation is associated with what IBD condition
Crohns disease
HLA is associated with what IBD condition
Ulcerative colitis
What is the pathology of IBD
Strong exaggerated immune response against normal flora due to a defects in the epithelial barrier function allowing microbes access to muscle lymphoid tissue
What is required for the diagnosis
Clinical history Radiographic examination Pathological correlation pANCA (perinuclear antineutrophilic cytoplasmic antibody)
What is the presentation go Ulcerative colitis
Can be localised to the rectum (proctitis)
More commonly spreads proximally
10% Pancolitis, +/- “backwash ileitis”
Appendix can be involved
Association with systemic manifestations
What is the pathology of UC
A continous pattern of inflammation in the large bowel only starting rectum to proximal
Results in
Pseudopolyps
Ulceration
Minimal or no inflammation on serosal surface
Where is UC mostly limited to histologically
Mucosa and submuscia
What happens to the mucosa in UC
Inflammation causing Cryptitis Crypt abscesses Mucosal atrophy
What happens to the submucosa in UC
Ulceration resulting in pseuodopolyps
submucosal fibrosis
What is the complications of UC
Dysplasia can occur increasing risk of cancer if adenomatous change
Haemorrhage
Perforation
Toxic dilatation
What do crohns and UC both have in common
Both have systemic manifestation
What is the pathology of crohns disease
= Granular serosa
Wrapping of mesenteric fat means
- Mesentry
= thickened, oedematous and fibrotic - Wall
= thick and oedematous
so overall narrowing of the lumen occurs
Resulting in Sharp demarcation of disease segments from adjacent normal tissue “skip
lesions”
Ulceration- “cobblestone”
What is present in the histology of crohns disease
Cryptitis and crypt abscesses
Architectural distortion
Atrophy –crypt destruction
Ulceration-deep
Transmural inflammation
(Chain of pearls)
Non-caseating granulomas
Fibrosis
Lymphangiectasia
Hypertrophy of mural nerves
Paneth cell metaplasia
What IBD disease has granulomas present
Crohns
What is the complications of CD
Small intestine malabsorbtion
Strictures
Fistulas
Abscesses
Perforation
Increased risk of cancer.
How does ischeamic enteritis occur
Acute occlusion of 1 of the 3 major supply vessels leads to infarction - (Coeliac, Inferior and Superior mesenteric arteries)
Leading to hypo perfusion injuring mucosal and/or submucosal
Is either acute or chronic
