Inflammatory Bowel Disease Flashcards
Examples of IBD
Ulcerative colitis
Crohn’s disease
What is UC
Continuous chronic inflammation of only the colon
What is Crohn’s disease
Intermittent chronic inflammation of the entire GI tract
Difference between UC and Crohns
- Ulcerative colitis is limited to the colon while Crohn’s disease can occur anywhere along GI tract
- In Crohn’s disease, there are healthy parts of the intestine mixed in between inflamed areas. Ulcerative colitis, on the other hand, is continuous inflammation of the colon
- Crohns = skip lesions; UC = continous
- Ulcerative colitis only affects the inner most lining of the colon (crypt abscesses) while Crohn’s disease can occur in all the layers of the bowel walls (transmural inflammation)
- Crohns has more genetic component (NOD2)
Clinical presentation of UC
5Ps: (signs and symptoms) Pyrexia Pseudopolyps lead Pipe radiological appearances Poo (bloody diarrhoea) Proctitis
Recurrent diarrhoea, often with blood and mucus
Some extra gastrointestinal manifestations: arthralgia, fatty liver and gall stones
Which IBD does smoking protect you against and which does it cause damage to it
UC - smoking protects
Crohns - smoking damages
Pathophysiology of UC
Mucosal inflammation originating in the anus and continuously progressing proximally
No granulomata
Goblet cell depletion and crypt abcesses
Clinical presentation of Crohns
Symptoms depend on the region affected.
Small bowel: Weight loss, abdominal pain.
Terminal ileum: Right iliac fossa pain mimicking appendicitis.
Colonic: Blood and mucus with diarrhoea, with pain.
Pathophysiology of Crohns
Transmural inflammation with granulomata in 50% of cases.
Ocurs anywhere in the GI tract with ‘skip lesions’.
Deep ulcers and fissures -> cobblestone appearance.
Aetiology of IBD
Genetics: Mild genetic link (Strong in Crohn’s).
Environmental: Stress and depression -> attacks.
Immune response: Effector T cells predominating over regulatory T cells -> Pro-inflammatory cytokines (IL-12, IL-5, IL-17 and interferon gamma/IFG) -> Stimulate macrophages to produce Tumour Necrosis Factor Alpha, IL-1 and IL-6. Neutrophils, mast cells and eosinophils are also activated. All this causes a wide variety of inflammatory mediators -> Cell damage
Epidemiology of IBD
Usually presents in teens and 20s. Common In northern europe. 400 per 100,000 in UK. Smoking is a RF.
Diagnosis of IBD
Seek to distinguish between UC and Crohns.
Sigmoidoscopy/rectal biopsy
Treatment of UC
5-Aminoslicylic acid (mesalazine) - drug of choice for remission and relapse prevention
Surgical resection
Complications of UC
Psychosocial and sexual problems Frequent relapse Colorectal cancer risk doubled Osteoporosis from steroid use Toxic megacolon Primary sclerosing cholangitis
Treatment of Crohn’s
Stop smoking.
Corticosteroids induce remission (but don’t prevent relapse).
Thiopurines maintain remission (but have side effects) Azathioprine
Complications of Crohns
Bowel obstruction from strictures May cause short stature in children Osteoporosis Anaemia Fistula formation Pyoderma gangrenosum
Similarities of UC and Crohns
- Both diseases often develop in teenagers and young adults although the disease can occur at any age
- Ulcerative colitis and Crohn’s disease affect men and women equally
- The symptoms of ulcerative colitis and Crohn’s disease are very similar
- The causes of both UC and Crohn’s disease are not known and both diseases have similar types of contributing factors such as environmental, genetic and an inappropriate response by the body’s immune system
Symptoms of Crohns
Diarrhoea Abdominal pain Weight loss/failure to thrive Systemic symptoms: fatigue, fever, malaise, anorexia
Signs of Crohns
Bowel ulceration Abdominal tenderness/mass Perianal abscess/fistulae/skin tags Anal strictures Beyond gut:Clubbing, Skin, joint and eye problems (systemic problems also)
Symptoms of UC
Episodic or chronic diarrhoea (with or without blood and mucus) Crampy abdominal discomfort Bowel frequency relates to severity Systemic symptoms in severe/attacks: fever, malaise, anorexia, decreased weight
Signs of UC
May be none
In acute UC may be fever, tachycardia and a tender dissented abdomen
Extraintestinal signs = clubbing, aphthous oral ulcers, conjunctivitis, large joint arthritis etc
Which IBD is associated with granuloma formation
Crohns disease
Conservative treatment of ulcerative colitis
Patient education; smoking has been shown to be protective but is not advised
Medical treatment of ulcerative colitis
1st line: 5-aminosalicylic acid analogues (5-ASA analogues) 2nd line: Corticosteroids Mesalazine 6-mercaptopurine Azathioprine
Example of 5-aminosalicylic acid analogue
Sulfasalazine
Surgical treatment of ulcerative colitis
Colectomy
Conservative treatment of Crohns disease
Smoking cessation
Low residue diet may be encouraged, but usually diet is normal
Medical treatment of Crohns disease
- Corticosteroids
- Immunosuppressants
Infliximab (TNF alpha inhibitor and thus immunosuppressant)
5-ASA analogues (sulfasalazine)
Azathiopurine (prevents flare up as its an immunosuppressant)
Methotrexate
Thiopurine (retains remission)
Surgical treatment of Crohns disease
Remove strictured or obstructed region of bowel
What is ulcerative colitis
This is a relapsing remitting autoimmune condition that is NOT associated with granulomas.
It affects the colon and rarely the terminal ileum (backwash ileitis)
What is Crohns disease
This is a disordered response to intestinal bacteria with transmural inflammation
It may affect any part of the gastrointestinal tract but often targets the terminal ileum
Associated with granuloma formation
Investigations of UC or Crohns
Bloods - FBC and platelets, U and Es, LFTs and albumin, ESR and CRP
Colonoscopy (DIAGNOSTIC)
Radiology - small bowel follow through (diagnostic) and abdominal X-ray (for toxic megacolon and excluding perforation)
Corticosteroid function
Stop production of prostaglandins which stops inflammation
5-ASA acid fucntion
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