Teaching Clinic - Inflammatory bowel disease Flashcards
What are environmental factors of IBD?
- Infection
- Antibiotics: gut microbiota alteration (dietary and bacterial antigens penetrate intestinal wall) and activate immune system to produce inflammation
- Diet
- Smoking
- Stress
- Drugs (NSAIDs)
Crohns Disease vs Ulcerative Colitis
- Region of involvement
- Pattern of lesions
Crohns disease
* Affects mouth to anus and transmural involvement
* Regional enteritis: skip lesions
* Granulomatous enteritis: secondary to granulomas
Ulcerative colitis
* Affects colon and mucosal involvement (except in backwash ileitis)
* Continuous lesions
Crohns disease pattern of distribution in bowel?
- Small bowel disease: 80%, with one-third ileitis only
- 50% ileocolitis
- 20% colon only
- <5% mouth or gastroduodenal area
Crohns disease common clinical features?
Crohns disease endoscopic features?
A. Early: apthous ulcers
B. Large ulcer interspersed with normal mucosa
C. Cobblestone appearance: nodular thickening, with linear or serpiginous ulcers
D. Stricture due to fibrosis
Other GI features of Crohns disease?
Phlegmon/ abscess
Perianal disease (skin tags, anal fissure, perirectal abscesses)
Malabsorption: bile salt malabsorption
What is the ddx for crohns disease?
How to make dx of Crohns disease?
Avoid doing capsule endoscopy: if necessary then do barium meal through study first
What lab Ix for crohns disease?
What is the crohns disease activity index (CDAI)? (no need to remember)
What are CD complications?
Fistula formation
Perforation/ abscess
Stricture/ SB obstruction
Nutrition deficiencies: Vit B12 (TI disease or resection)
Increased risk of adenoCA
What is the ulcerative colitis disease pattern?
SS of ulcerative colitis
Ix for UC?
- Clinical features (bloody diarrhea)
- Laboratory studies
- Endoscopy (colonoscopy)
- Histology
Colonoscopy features of UC?
Histology of UC
- Plasma cell infiltration
- Lymphocytes,macrophages
- Crypt abscess
No granuloma formation
ddx for UC?
Infection: bacterial colitis (salmonella, shigella, campylobacter, Yersinia, E coli 0157:H7, C difficile); Amoeba
Non-infectious: Crohn’s disease, ischemic colitis, radiation colitis
Immunocompromised: CMV and HSV
UC complications
Toxic megacolon: 15-50% mortality
Perforation
Cancer: increasing risk of dysplasia with increased time (except procitis). If proctitis only, then CA risks not increased.
summary of clinical findings, colonoscopy, radiologic and histologic findings for UC vs crohns disease
Extraintestinal manifestation of IBD
Arthritis: large joints, AS, sacroilitis
Uveitis, iritis, episcleritis
Erythema nodosum, pyoderma gangrenosum
Primary sclerosing cholangitis
Bone loss and osteoporosis
Vit B12 deficiency
Mild IBD treatment
- 5-ASA/ mesalamine: oral formula, suppository (preferred in rectal disease)
- Antibiotics: metronidazole (anaerobic bacteria)
Moderate to severe IBD treatment
- Corticosteroids
- Azathioprine and 6-mercaptopurine (purine analogs that inhibit T cell function): for maintenace. Action onset delay 3-6 months. Efficacy maintained up to 4 years post op. AE: pancreatitis, hepatotoxicity, bone marrow suppression
- Infliximab and other TNF inhibitors
Not a routine to check TPMT
AE to TNF inhibitors?
- Infection, multiple sclerosis, lupus-like reactions are common to all anti-TNFs
- Higher risk of common bacterial infections
- TB and fungal infections
- Before commencement (check HBsAg, QuantiFERON-TB Gold, CXR)
- Treat abscess (antibiotics + drainage), withhold anti-TNF
What is seen?
Toxic megacolon
Started in infliximab (check hep B, HIV, CMVp66 PCR (gancyclovir))
