Flashcards in Lower GI Tract Deck (13)
What's the lower GI tract made up of?
Small bowel and large bowel
What are the causes of malabsorption in the small bowel?
Extra intestinal diseases
Intestinal eg. Coeliac disease, tropical sprue, giardiasis, whipple's disease.
What's gluten sensitive enteropathy?
Look this up.
Coeliac disease which shows on hydrology as: villus atrophy, crypt hyperplasia, lymphocytes in the epithelium.
What's tropical sprue?
A cause of intestinal malabsorption. Seen in the tropics (not Africa).
Caused by abnormal bacterial colonisation. Its treatment is antibiotics.
A cause of intestinal (small bowel) malabsorption. Caused by Giardia Lamblia bacteria which is found in contaminated water, food, hands etc.
What's whipple's disease?
Causes intestinal (small bowel) malabsorption. Caused by Tropheryma whippelii.
Pathology: accumulation of macrophages.
Clinical: malabsorption, skin changes, joint pain.
What are examples of chronic idiopathic inflammatory bowel disease?
What's ulcerative colitis?
It's an inflammatory bowel disease whose aetiology is unknown but thought to possibly be autoimmune and maybe genetic factors: HLA-DR2.
It's not infective. It only affects the LARGE BOWEL.
Macroscopic appearances: red mucosa/granular/bleeding. Linear ulcers.
Histological features: inflammation of the mucosa (only the mucosa is inflamed), cryptitis, crypt abscess, regenerative brancrd crypts, inflammatory polyps.
Clinical features: diarrhoea, bleeding.
Complications: toxic megacolon, malignancy.
What's Crohn's disease?
Can affect ANY part of the gut but the ileum is most common. Inflammation is transmittal (not just mucosal). Patchy disease.
Aetiology is unknown but it's autoimmune in genetically predisposed.
Appearance: ulcers, hosepipe structures, cobblestone appearance.
Histology: transmural inflammation, crypt abscess, fissuring ulceration, granuloma.
Clinical features: in the small bowel malabsorption, obstruction, anaemia. In the large bowel bleeding and diarrhoea.
Complications: fistula, perforation (rare), malignancy.
Smoking is a high risk for Crohn's.
What are the systemic complications of ulcerative cholitis and Crohn's?
Skin: pyoderma gangrenosum.
Liver: PSC (look this up)
What are polyps?
Masses projecting into the lumen, either sessile or pedunculated.
Can be: hyperplastic, neoplastic (adenoma), hamartoma.
An adenoma can progress to a carcinoma.
What are the causes of colorectal carcinoma?
Approx 15% are inherited. Diet could be a factor: fibre is protective and protein and fat could cause it?