Gastrointestinal Flashcards
What is the mortality risk for upper GI bleeds?
10%
What are the possible causes of an upper GI bleed?
50% due to peptic ulcers
oesophageal varices
What is considered an upper GI bleed?
bleeding from anywhere above the ligament of treitz
What does low Hb and high urea indicate?
bleeding
What is melaena?
black stools due to GI bleeding
What is the Glasgow-blatchford score?
a scoring system to grade risk of death for patients with upper GI bleeding
What is ABCDE?
Airway
Breathing
Circulation
Disability
Exposure
What is the difference between variceal bleeds and non-variceal bleeds?
variceal is due to bursting oesophageal varies
suspect variceal bleeds in patients with history of liver disease or alcohol excess, they have a higher mortality rate than non-variceal bleeds
What do patients with variceal bleeds die of?
sepsis
How are variceal bleeds treated?
antibiotics- to prevent sepsis
terlipressin
endoscopy within 12 hours
band ligation of varices
How are non-variceal bleeds treated?
proton pump inhibitors
endoscopy within 24 hours
cauterise/ clip ulcers that are bleeding
What are the causes of intraluminal obstruction?
tumour (carcinoma, lymphoma)
diaphragm disease
meconium ileum
gallstone ileus
What are the causes of intramural obstruction?
inflammatory (Crohn’s, diverticulitis)
tumours
neural (Hirschsprung’s)
What are the causes of extraluminal obstruction?
adhesions
volvulus
tumour (peritoneal deposits)
What are the causes of small bowel obstruction?
adhesions
hernia
cancer
What investigations can confirm a diagnosis of small bowel obstruction?
FBC
U+E
lactate
C-reactive protein
CT scan
What do we CT scan for small bowel obstructions?
localise site of obstruction
indicated cause
tells you if bowel is ischemic (poor enhancement, free fluid, twisted mesentery)
What is coeliac disease?
Inflammation of the mucosa of the upper small bowel that improves when gluten is withdrawn from the diet and relapses when gluten is reintroduced
Which protein causes coeliac disease?
prolamin intolerance (component of gluten protein)
Describe the pathophysiology of coeliac disease.
- a-Gliadin is resistant to digestion from protease enzymes (pepsin and chymotrypsin) in small intestine lumen
- passes through damaged epithelial wall and into cells
- deaminated by tissue transglutaminase
- interacts with antigen-presenting cells via HLA- DQ2
- These activate gluten-sensitive CD4+ T cells
- T-cells produce pro-inflammatory cytokines, leading to inflammatory cascade
- causes villous atrophy and crypt hyperplasia
What % of the population are affected by Coeliac disease?
~1%
but only ~25% of these people are diagnosed
What are the risk factors for coeliac disease?
other autoimmune conditions
IgA deficiency
What are the signs and symptoms of coeliac disease?
GI:
- weight loss
- fatigue and weakness
- diarrhoea
- abdominal pain
- bloating
- nausea and vomiting
- steatorrhoea and odorous stools
Dermatological:
- apthous ulcers (canker sore)
- angular stomatitis (redness at sides of mouth)
- dermatitis herpetiformis (raised red patches of skin and blisters due to deposition of IgA in skin)
- anemia
- failure to thrive in children
- osteomalacia
Why can coeliac disease present as osteomalacia?
decreased absorption of vitamin D due to malabsorption