Inflammatory bowel disease

Question 1

IBD - overview

Answer 1

1. CD, UC, CD 2x as common as UC
2. Incidence 5/100,000/yr
3. Cause unknown but recognised genetic disposition

Question 2

IBD - UC vs UC

Answer 2

UC

1. Involves colon only
2. Proctitis (rectum) is most common or may extend continuously up to involve the entire colon (pancolitis)
3. Terminal ileum may be affected by ‘backwash ileitis’

CD

4. May affect any part of GI tract, but terminal ileum + proximal colon are commonest sites of involvement
5. Unlike UC, bowel involvement is non-continuous (‘skip’ lesions)

Question 3

IBD - symptoms

Answer 3

1. Anorexia, weight loss, lethargy
2. Abdominal cramps
3. Diarrhoea +/- blood/mucus
4. Urgency and tenesmus (proctitis)
5. Fever

Question 4

IBD - signs

Answer 4

GI

1. Aphthous oral ulcers
2. Abdominal tenderness
3. Abdominal distension (UC>CD)
4. RIF mass (CD)
5. Perianal disease (CD) - i.e. abscess, sinus, fistula, skin tags, fissure, stricture

Non-GI signs and associations (5 + 5 = 10)
1. Fever
2. Finger clubbing
3. Anaemia
4. Poor growth, delayed puberty
5. Nutritional deficiencies (e.g. vitamin B12)
___
6. Skin = erythema nodosum (red tender lumps on shins), pyoderma gangrenosum (deep ulcers, usually on legs)
7. Joints = arthritis, ankylosing spondylitis
8. Eyes = iritis, conjunctivitis, episcleritis
9. Sclerosing cholangitis
10. Renal stones

Question 5

IBD - complications

Answer 5

1. ‘Toxic’ colon dilatation (UC>CD)
2. GI perforation or strictures; massive GI haemorrhage
3. Pseudopolyps (apparent ‘polyps’) resulting from inflammation
4. Colon carcinoma (UC = 50% risk after 10-20y of disease)
5. Fistula involving bowel only or bowel + skin/vagina/bladder (CD); abscesses (CD)

Check Toronto for differences between UC and CD in clinical presentation - ?

Question 6

IBD - ix

Answer 6

1. Bloods (10) = FBE, ESR (raised), CRP (raised), UEC, LFTs, albumin, blood cultures, serum iron (decreased), vitamin B12, folate (decreased)
2. Serum serological markers (ASCA better for CD, p-ANCA better for UC)
3. Stool MCS = checking for infectious colitis
4. Endoscopy + biopsy = colonoscopy to determine extent and pattern of abnormal mucosa + intestinal biopsy
   - UC histology = crypt abscesses, mucosal inflammation only, goblet cell depletion
   - CD = crypt abscesses, granulomas, transmural inflammation
5. Barium enema for both CD and UC - but role is fairly limited

Question 7

IBD - mx

Answer 7

1. Supportive tx = if severe, .e.g bowel rest, IV hydration, PN
2. Drug tx (initial)
   * UC
   - 5-aminosalicylic acid (ASA) orally (+ mesalazine if proctitis)
   - If no response, use prednisolone orally + taper over 6-8 weeks to cease (rectally if proctitis; budesonide or hydrocortisone PR are alternatives)
   * CD
   - Prednisolone orally, taper over 6-8 weeks to cease
   * Both (severe)
   - Use IV hydrocortisone or IV methylprednisolone
3. Maintenance therapy
   * UC
   - 5-ASA (+ mesalazine PR if used previously)
   - If frequent relapses, add azathioprine or mercaptopurine
   - If refractory to tx, add infliximab
   * CD
   - Azathioprine or mercaptopurine
   - If ineffective, consider methotrexate + folic acid
   - If refractory to tx, use infliximab or adalimumab
4. Dietary supplementation to minimise poor growth and correct specific nutritional deficiencies - e.g. vitamin and mineral supplements. Involve a paediatric dietitian
5. Surgery
   - UC = total colectomy and ileostomy, and later pouch creation and anal anastomosis; cures UC. 10-20% complication rate, e.g. pouchitis
   - CD = local surgical resection for severe localised disease, e.g. strictures, fistula. However, there is a high re-operation rate as inflammation recurrence is universal

Question 8

IBD - prognosis

Answer 8

1. Marked by relapse and remission
2. Can still have good QoL
3. Poor prognostic factors = extensive disease, frequent remissions, young age at dx