Teaching Clinic - Inflammatory bowel disease

Question 1

What are environmental factors of IBD?

Answer 1

• Infection
• Antibiotics: gut microbiota alteration (dietary and bacterial antigens penetrate intestinal wall) and activate immune system to produce inflammation
• Diet
• Smoking
• Stress
• Drugs (NSAIDs)

Question 2

Crohns Disease vs Ulcerative Colitis
- Region of involvement
- Pattern of lesions

Answer 2

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

Question 3

Crohns disease pattern of distribution in bowel?

Answer 3

• Small bowel disease: 80%, with one-third ileitis only
• 50% ileocolitis
• 20% colon only
• <5% mouth or gastroduodenal area

Question 4

Crohns disease common clinical features?

Answer 4

Question 5

Crohns disease endoscopic features?

Answer 5

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

Question 6

Other GI features of Crohns disease?

Answer 6

Phlegmon/ abscess
Perianal disease (skin tags, anal fissure, perirectal abscesses)
Malabsorption: bile salt malabsorption

Question 7

What is the ddx for crohns disease?

Answer 7

Question 8

How to make dx of Crohns disease?

Answer 8

Avoid doing capsule endoscopy: if necessary then do barium meal through study first

Question 9

What lab Ix for crohns disease?

Answer 9

Question 10

What is the crohns disease activity index (CDAI)? (no need to remember)

Answer 10

Question 11

What are CD complications?

Answer 11

Fistula formation
Perforation/ abscess
Stricture/ SB obstruction
Nutrition deficiencies: Vit B12 (TI disease or resection)
Increased risk of adenoCA

Question 12

What is the ulcerative colitis disease pattern?

Answer 12

Question 13

SS of ulcerative colitis

Answer 13

Question 14

Ix for UC?

Answer 14

• Clinical features (bloody diarrhea)
• Laboratory studies
• Endoscopy (colonoscopy)
• Histology

Question 15

Colonoscopy features of UC?

Answer 15

Question 16

Histology of UC

Answer 16

• Plasma cell infiltration
• Lymphocytes,macrophages
• Crypt abscess

No granuloma formation

Question 17

ddx for UC?

Answer 17

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

Question 18

UC complications

Answer 18

Toxic megacolon: 15-50% mortality
Perforation
Cancer: increasing risk of dysplasia with increased time (except procitis). If proctitis only, then CA risks not increased.

Question 19

summary of clinical findings, colonoscopy, radiologic and histologic findings for UC vs crohns disease

Answer 19

Question 20

Extraintestinal manifestation of IBD

Answer 20

Arthritis: large joints, AS, sacroilitis
Uveitis, iritis, episcleritis
Erythema nodosum, pyoderma gangrenosum
Primary sclerosing cholangitis
Bone loss and osteoporosis
Vit B12 deficiency

Question 21

Mild IBD treatment

Answer 21

• 5-ASA/ mesalamine: oral formula, suppository (preferred in rectal disease)
• Antibiotics: metronidazole (anaerobic bacteria)

Question 22

Moderate to severe IBD treatment

Answer 22

• 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

Question 23

AE to TNF inhibitors?

Answer 23

• 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

Question 24

What is seen?

Answer 24

Toxic megacolon
Started in infliximab (check hep B, HIV, CMVp66 PCR (gancyclovir))