Inflammatory Bowel Disease
(somewhat of a misnomer as Crohn can extend beyond s/l intestine)
2 distinct chronic inflammatory intestinal diseases
idiopathic
Can present from 1yo but generally early onset is 10-20y (25%) (Late onset at 50-80y)
Genetic (NOD2, IBD5)
~20% chase of developing if 1 parent has IBD, >35% if both
If relative has IBD more likely to get the same one eg UC if relative has UC, both at risk of both
Cigarettes increased risk of Crohn, but protects against UC
Crohn Disease (mouth to anus)
(indeterminate colitis when cant decide which ~10%)
Pathology: Crohn v UC
Transmural involvement Common Unusual
- Strictures Common Rare
- Abdominal pain Common Variable
- Abdominal mass Common Not present
Mouth ulceration Common Rare
Stomach-esophageal disease More common Chronic gastritis can be seen
Ileal disease Common None except backwash ileitis
- Growth failure Common Variable
Discontinuous (skip) lesions Common Not present
Granulomas Common None
Perianal disease/Fissures/Fistulas Common Rare
Erythema nodosum Common Less common (erythema swelling inflammation of from subcutaneous fat)
Risk for cancer Increased Greatly increased
Colonic disease 50-75% 100%
Rectal involvement Occasional Universal
Rectal bleeding Sometimes Common
Diarrhea, mucus, pus Variable Common
Toxic megacolon None Present
Crypt abscesses Less common Common
Linear ulcerations Uncommon Common
Pyoderma gangrenosum Rare Present (rapidly enlarging ulcer)
Thrombosis Less common Present
Sclerosing cholangitis Less common Present
Rx
Stop smoking in crohn
Screen for latent infection before commencing immunomodulators (HepB, TB, HIV...)
Immunised prior to immunomodulation (check immunity)
see immunosuppression to standard workup before immunosuppression
Corticosteriods (both)
Azathioprine and mercaptopurine (Crohn)
Cyclosporin (IBD)
2 distinct chronic inflammatory intestinal diseases
idiopathic
- perinuclear antineutrophil antibody (pANCA) pos in ∼70% of UC, <20% with Crohn's
- 'physiologic' inflammation normal in bowel from high antigen/infectious load becomes pathological
Can present from 1yo but generally early onset is 10-20y (25%) (Late onset at 50-80y)
Genetic (NOD2, IBD5)
~20% chase of developing if 1 parent has IBD, >35% if both
If relative has IBD more likely to get the same one eg UC if relative has UC, both at risk of both
Cigarettes increased risk of Crohn, but protects against UC
Crohn Disease (mouth to anus)
- if presents in very young generally
(indeterminate colitis when cant decide which ~10%)
Pathology: Crohn v UC
Transmural involvement Common Unusual
- Strictures Common Rare
- Abdominal pain Common Variable
- Abdominal mass Common Not present
Mouth ulceration Common Rare
Stomach-esophageal disease More common Chronic gastritis can be seen
Ileal disease Common None except backwash ileitis
- Growth failure Common Variable
Discontinuous (skip) lesions Common Not present
Granulomas Common None
Perianal disease/Fissures/Fistulas Common Rare
Erythema nodosum Common Less common (erythema swelling inflammation of from subcutaneous fat)
Risk for cancer Increased Greatly increased
Colonic disease 50-75% 100%
Rectal involvement Occasional Universal
Rectal bleeding Sometimes Common
Diarrhea, mucus, pus Variable Common
Toxic megacolon None Present
Crypt abscesses Less common Common
Linear ulcerations Uncommon Common
Pyoderma gangrenosum Rare Present (rapidly enlarging ulcer)
Thrombosis Less common Present
Sclerosing cholangitis Less common Present
Rx
Stop smoking in crohn
Screen for latent infection before commencing immunomodulators (HepB, TB, HIV...)
Immunised prior to immunomodulation (check immunity)
see immunosuppression to standard workup before immunosuppression
Corticosteriods (both)
- for induction (1-2 weeks) then wean (not effective for maintenance)
- For induction ?maintenance
- poorly absorbed anti-inflammatory: mode of action unclear
- Mesalazine
- sulfasalazine
Azathioprine and mercaptopurine (Crohn)
- Induction and maintenance
- Steriod sparing
- Purine antimetabolite. Azathioprine > mercaptopurine > thioguanine nucleotides, which interfere with purine synthesis, impairing lymphocyte proliferation, cellular immunity and antibody responses.
Cyclosporin (IBD)