Pathology of Colon Flashcards
What is the functional difference between the small and large bowel?
Small bowel has absorptive role
Large bowl has absorptive and secretory role
What are some features of small bowel histology?
Goblet cells
Columnar absorptive cells
Endocrine cells
Loads of villi
What are some features of large bowel histology?
Flat (no villi)
Tubular crypts
Columnar absorptive cells at surface
What parts of the GI tract may be affected by Crohn’s?
All parts from mouth to anus
What parts of the GI tract may be affected by UC?
Just the colon
Which gene is associated with Crohn’s?
NOD2
Which gene is associated with UC?
HLA
What are some possible complications of UC?
Haemorrhage
Perforation
Toxic dilation
Are granulomas seen in UC?
No
What are some common features of UC?
Pseudopolyps
Ulceration
No granulomas
What are some histological features of Crohn’s Disease?
Crypt inflammation and abscess Ulceration Transmural inflammation Non-caseating granulomas Fibrosis Lymphangiectasia
What is a granuloma?
Area of inflammation
Collection of macrophages
What does caseating mean?
Diseased tissue forms a firm, dry mass like cheese in appearance.
What is lymphangiectasia?
Pathological dilation of lymph vessels
What is ischaemic enteritis?
A major vessel occlusion leads to infarction and transmural injury
What conditions may cause ischaemic enteritis?
Arterial thrombosis
Arterial embolism
Non-occlusive ischaemia
What conditions may predispose an individual to arterial thrombosis?
Artherosclerosis
Dissecting aneurysm
Hypercoagulable states
Oral contraceptive
What conditions may predispose an individual to arterial embolism?
Cardiac vegetations
Cholesterol embolism
What conditions may predispose an individual to non-occlusive ischaemia?
Cardiac failure
Shock
Vasoconstriction
What is appendicitis?
Acute inflammation of the appendix causes by obstruction
Fibrinopurulent exudate
Perforation
Abscess
What are some possible causes of lower GI bleeds?
Diverticular disease Haemorrhoids Angiodysplasia Neoplasia (carcinoma/polyps) Ischaemic colitis Radiation enteropathy Proctitis IBD
What is ischaemic colitis?
Blood supply to colon is disrupted
Crampy abdominal pain
Usually self limiting
