Inflammatory Bowel Disease

Inflammatory Bowel Disease (IBD) is where there's chronic inflammation of the gut wall with periods of remission and exacerbation. Patients present with:

• Diarrhoea

• Mucous/blood in stool

• Abdominal pain - LLQ with UC, RLQ with Crohn’s

• Weight loss

Differentials - IBS (diagnosis of exclusion), Diverticulitis, and Appendicitis.

Investigations:

• Bloods - FBC, U&E, LFT, CRP, ESR, INR, Ferritin, B12, Folate, TFT, Albumin

• Stool culture - exclude c.diff

• Faecal Calprotectin - Raised in IBD, therefore differentiating it from IBS

N.B. Faecal calprotectin can also be raised with NSAIDs and PPIs.

Crohn’s:

This is characterised by transmural inflammation, which affects the entire GI tract. The terminal ileum and proximal colon (RLQ) is the most common area affected. The manifestations of this disease are:

• Mouth ulcers

• Perianal abscesses/fistulas, Skin tags

• Erythema nodosum

• Anterior uveitis

• Gallstones

Smoking is a major risk factor here.

Investigations:

• Colonoscopy - Skip lesions, Cobblestone appearance (due to ulceration and mural oedema), Non-caseating granulomas

• CT/MRI - Bowel wall thickening, Increased bowel wall brightness (damaged area takes up more contrast), Comb sign (Hyper-vascularity of mesentery)

Complications:

• Strictures

• Fistulas

• Adhesions

Management:

Conservative - Smoking cessation

Induce remission - Steroids (1st line) e.g. pred, hydro

• Azathioprine or Methotrexate 2nd line

Maintain remission - Azathioprine (1st line)

• Methotrexate 2nd line

Ulcerative Colitis:

This is characterised by inner mucosal inflammation, which only affects the colon. The manifestations of this disease are:

• PR blood and mucous

• Anterior uveitis

Investigations:

• Colonoscopy - Continuous inflammation, Crypt abscesses (full of neutrophils)

• CT/MRI

  • Thumbprinting - thickened mucosal folds due to bowel wall oedema)

  • Lead piping - occurs in chronic cases as bowel becomes featureless w/loss of haustral marking, luminal narrowing and bowel shortening

Complications:

• Toxic megacolon

• Colorectal cancer

• Primary Sclerosing Cholangitis

• Cholangiocarcinoma

• Stricture

Management:

Induce remission:

• Mild-moderate disease - Topical/Oral Aminosalicylate (1st line) e.g. Mesalazine. Consider adding prednisolone if no response in 72 hours.

• Severe disease - IV Prednisolone (1st line). Add IV Ciclosporin or consider surgery if no response in 72 hours.

Maintain remission - Topical/Oral Aminosalicylate

Curative - Total panproctocolectomy