GI Diseases Flashcards
Where is stomach acid produced?
Parietal cells in the stomach.
What do proton pump inhibitors do?
Prevent stomach acid secretion into the stomach.
- prevents the excretion of hydrogen ions from the parietal cells, so that HCL cannot be made.
What is GORD?
Gastro-oesophageal reflux disease.
What are the three main causes of GORD?
Defective lower oesophageal sphincter.
Impaired lower clearing
Impaired gastric emptying.
What are the signs and symptoms of GORD?
Epigastric burning- worse laying down.
Dysphagia.
GI bleeding
Severe pain- mimics MI.
What is the long term effect of GORD?
Ulceration of the oesophagus, inflammation.
Barrett’s oesophagitis- stratified squamous epithelium converts to columnar- precancerous.
What can cause dysphagia?
External compression from lungs, aorta, atrial enlargement. GORD
Parkinson’s
Diabetes melitus
Achalasia
What is peptic ulcer disease?
Discontinuation of the mucosal lining of parts of the GI tract caused by acid.
What can cause peptic ulcer disease?
Drugs- NSAIDs, steroids
High acid secretion- oesophageal, duodenal
Normal acid secretion- stomach, associated with H.Pylori
What are the effects of H.Pylori?
Gastric ulcers
Chronic gastric wall inflammation
Lymphoma of the stomach- causes activation of lymphoid tissue in the gastric wall.
What are the signs and symptoms of peptic ulcer disease?
Epigastric burning- worse before’ just after meals, worse at night, relieved with food, alkali and vomiting.
Usually no physical signs- i.e. bleeding.
What medication must be avoided in people with peptic ulcer disease?
NSAIDs- inhibit COX-1in the GI tract which leads to a reduction in prostaglandin secretion.
Less cytoprotective effects in the GI tract.
What medication is used for PUD?
Proton pump inhibitors.
Triple therapy for H.Pylori.
What is coeliac disease?
sensitivity to alpha-gliaden component of gluten.
What happens if someone with coeliac disease eats alpha-gliaden?
Alpha-gliaden is absorbed in the small intestine.
Produces an immune response, autoantibodies produced- TTG and anti-gliadin/anti-endomyseal antibodies.
T cells produced- damages mucosal tissue.
Causes villous atrophy of the jejunum, loss of surface area, reduced absorption.
What are the histological signs of coeliac disease?
Villous atrophy
Lymphoid tissue infiltration
Lamina propria inflammation
What oral effects occur in coeliac?
Aphthous ulceration
Tongue papillary loss
What other extra-oral symptoms of coeliac disease are there?
Weight loss
Weakness
Abdominal pain/swelling
Diarrhoea
Dysphagia
Steatorrhoea
What is Dermatitis Herpetiformis?
Associated with coeliac disease.
Causes ulceration abd listers in the mouth and blister on the skin caused by granular igA deposition within the tissue.
Causes loss of adhesion between the epithelium and the connective tissue- inflammatory exudate forms between the two tissues.
If you suspect coeliac disease, what investigations would you suggest?
Autoantibody test- TTG, anti-gliadin/anti-endomyseal antibodies.
Jejunal biopsy
Faecal fat
Haematinics
What is Crohn’s disease?
Chronic inflammatory condition which affects the full thickness of the bowel wall and anywhere within the GI tract, from the oral cavity to the anus.
What signs are present in Crohn’s disease?
Mucosa is thickened, entire wall is thickened, with a very narrow lumen.
Granulomas- multinucleate cells which causes blockage of lymphatics.
lymphocytes throughout the wall of the bowel.
Cobblestone appearance in the bowel wall and also seen in the mouth- tissue oedema separated by fibrous bands.
What is Ulcerative colitis?
Chronic inflammatory condition which affects the rectum and terminal part of the large intestine.
Starts in the rectum and works its way back.
What are the main differences with UC and Crohn’s?
UC is continuous from the rectum, whereas Crohn;s is discontinuous and can develop anywhere in the GI tract.
Crohn’s disease can extend to the skin, UC is unlikely to do so.
UC has a more vascular appearance, increased vascular supply and inflammatory changes, whereas Crohn’s is cobbled and fissures.
UC only extends through the superficial layer of the gut wall- present until the submucosal layer.
What are the symptoms of inflammatory bowel diseases?
Abdominal pain
Diarrhoea
PR bleeding
In crohn’s- orofacial granulomatosis.
What is a long term risk of UC?
Carcinoma.
What medication might someone with Crohn’s or UC be on?
Systemic steroids- prednisolone.
Anti-inflamamtory drugs.
Non-steroid immunosuppressants- methotrexate, axothioprine.
Anti- TNFalpha therapy- infliximab.
