Crohn's Flashcards
compare crohn’s and ulcerative colitis?
Define crohn’s disease?
outline the aetiology of crohn’s disease?
- Cause unknown but thought to be due to interplay between genetic and environmental factors
Th1 mediated, with main cytokine being TNF-a. As it is Th1-mediated, causes more severe inflammatory response which can penetrate all the way through the gut and affect any point of GI tract from mouth to anus.
Inflammation can occur anywhere from mouth to anus - 40% involves the terminal ileum
In the terminal ileum you have many lymphatic cells so more Imms
Usually there are ‘skip’ lesions with inflamed segments of bowel interspersed with normal segments – hence, can’t remove affected areas surgically as easily as UC
Characterised by COBBLESTONE appearance – as different areas of inflammation heal differently and there is inflammation in patches
Likely to get abscesses, fissures (perforation through bowel) and fistulae (abnormal fusion between a hollow tubular organ and the body surface, or between two hollow/tubular organs – makes sense for chron’s because it goes through all the layers)
summarise the epidemiology of crohn’s disease?
Affects any age but peaks in teens, 20s and 40s
Think 25yr old Jewish
SMOKERS
what are the risk factors for crohn’s disease?
white ancestry
age 15-40 age 60-80 years old
family history of CD
what are the presenting symptoms of CD?
Crampy abdominal pain (due to inflammation, fibrosis or bowel obstruction)
Diarrhoea (may be bloody or steatorrhoea)
Fever, malaise, weight loss
fatigue- malnutrition, weight loss and inflammation
Sometimes right iliac fossa pain due to inflammation of terminal ileum
what are the signs of CD on physical examination>
Weight loss
Clubbing
Signs of anaemia
Aphthous ulcers in mouth
Perianal skin tags, fistulae and abscesses
Signs of complications: Uveitis, erythema nodosum, pyoderma gangrenosum
APIESAC: Aphthous ulcers, pyoderma gangrenosum, iritis, erythema nodosum, sacroilitis (back pain), arthritis, clubbing
describe the investigations for crohns
raised inflammatory markers
increased faecal calprotectin
anaemia
low vitamin B12 and vitamin D
what is seen on endoscopy?
Deep ulcers, skip lesions - ‘cobble-stone’ appearance
describe the radiology appearance?
Small bowel enema
high sensitivity and specificity for examination of the terminal ileum
strictures: ‘Kantor’s string sign’
proximal bowel dilation
‘rose thorn’ ulcers
fistulae
describe the induction of remission in crohns?
- STEROIDS (oral or IV +/- topical)
- Prednisolone, Budesonide - IMMUNOMODULATORS (oral or IV)
- Azathioprine, Mercaptopurine, Methotrexate - BIOLOGICAL THERAPY (IV)
- Adalimumab, Infliximab, Vedolizumab - SURGERY
- For severe remissions/presentation, refractory disease and obstructed pts
describe how remission is maintained in crohns ?
•IMMUNOMODULATORS
•Azathioprine, Mercaptopurine, Methotrexate
•+ / - BIOLOGICS
•Infliximab, Adalimumab, Vedolizumab
what is the general advice given to people with crohns?
patients should be strongly advised to stop smoking
some studies suggest an increased risk of relapse secondary to NSAIDs and the combined oral contraceptive pill but the evidence is patchy
when is surgery indicated for crohns?
Medical treatment fails
Failure to thrive in children in the presence of complications
Involves resection of affected bowel and stoma formation - NOTE: there is a risk of disease recurrence
what are the GI complications of crohns?
Haemorrhage
Strictures
Perforation
Fistulae (between bowel, bladder, vagina)
Perianal fistulae and abscesses
GI cancer
Malabsorption
compare the extra-intestinal features of CD and UC?
