Makindo Medical Notes.com

Related Subjects: |Colorectal cancer |Colorectal polyps |Ulcerative Colitis |Acute Severe Colitis |Crohn's disease

Anti-TNF agents have improved the ability to achieve and maintain remission

About

• A chronic relapsing inflammatory granulomatous disease
• Can affect any part of the Gut from mouth to anus
• UK incidence 5-8/100,000 per year
• UK prevalence is 50-80 per 100,000

Aetiology

• Caucasion/Jewish, Smoking is a risk factor x 3-4
• Familial types - polymorphisms in NOD2/CARD15 gene on chromosome 16 correlate ileal disease
• Exposure to antigens, Oral contraceptive increases the risk

Pathology

• The inflammation is oedematous with granulomatous transmural inflammation
• Granulomas deep and may not be seen in biopsies. Deep ulcers.
• Skip lesions are seen i.e. 2 affected areas with unaffected bowel between
• Deep ulceration and fistula formation may be seen
• Fistulas - bladder, uterus, vagina

Disease Location - Discontinuous skip lesions

• Terminal Ileal disease 90%
• Ileocolonic 40%
• Small intestine 40%
• Crohn's colitis 20%
• Perianal disease < 10% - rectal sparing in the vast majority

Clinical

• Proximal small bowel disease - crampy abdominal pain - inflammation, fibrosis, partial bowel obstruction, weight loss, anorexia.
• Terminal ileal disease - Right lower quadrant pain mimicking appendicitis, right lower quadrant inflammatory mass, Malabsorption, Steatorrhoea
• Colonic disease - Crohn's colitis with diarrhoea which may be bloody with mucus
• Perianal lesions - skin tags and fistula, abscesses
• Finger clubbing and anaemia, Fever malaise, Mouth ulcers

Complications

• Eye - Uveitis, Episcleritis, Conjunctivitis
• Kidney stones - due to raised oxalate in urine
• Arthropathy, Sacroiliitis , Ankylosing spondylitis
• Erythema nodosum, Pyoderma gangrenosum, Amyloidosis
• Risk of colonic malignancy with long term Crohn's colitis
• Increased Venous thromboembolism

Investigations

• ? Hb ? B12 ?folate ? ferritin
• ?Elevated WCC and ? platelets
• ? ESR ?CRP correlates with disease activity
• LFT's, Bone profile
• Stool for ova, cysts and parasites
• Capsule endoscopy for staging small bowel disease
• AXR - look for obstruction
• Small bowel barium follow-through - "string sign of Kantor", deep rose thorn ulcers, cobblestone mucosa.
• CT with contrast has a high sensitivity for disease
• Small bowel histology usually not needed where diagnosis clear but one can do a technetium labelled white cell scan to pick up areas of disease activity
• Where the diagnosis is in doubt laparotomy and resection and biopsy may be needed
• MRI - best for assessing perianal disease
• OGD/Colonoscopy for biopsies
• Positive antibody to Saccharomyces cerevisiae in 60%

Differential

• Tuberculosis
• Yersinia

Management

• Mild disease is managed with a reducing dose of Prednisolone over 1 month. Such as Prednisolone 40mg for one week then 20 mg thereafter. Sulfasalazine or Mesalazine (Pentasa) 500 mg qds is only in Crohn's colitis in inducing remission. Given orally, rectally.
• Moderate disease really involves more pronged course of oral Prednisolone. Steroid enemas for proctosigmoid disease. Budesonide may be preferred as less pronounced side effects. There is a pattern of ongoing episodes of intestinal obstruction which need hospitalization and IV fluids and a Nasogastric tube for gastric decompression. May settle conservatively. Steroids may be followed up by immunosuppressive therapy with azathioprine or methotrexate.
• Severe disease really encompasses the acute abdomen and toxic megacolon. Severe colitis - life-threatening colonic inflammation can occur in inflammatory bowel disease even with the initial attack of colitis. There is abdominal pain and the patient is toxic. AXR shows dilated bowel, thumb printing and mucosal oedema and if bowel diameter > 6 cms there is a high risk of perforation. Joint care from both gastroenterologists and surgeons. Transfuse > 10 g/dl. IV methylprednisolone. Nutritional support, Antibiotics, VTE prophylaxis. Consider IV Ciclosporin or Infliximab or Adalimumab if no response to high dose steroids after 3-5 days reduces the need for surgery. Laparotomy and urgent colectomy if fails to settle.
• Fistulating Crohn's: Treatment may not be needed if asymptomatic perianal disease. Some may need Metronidazole or Ciprofloxacin depending on location and anatomy and some may need surgery. Pelvic MRI is the imaging modality of choice.
• Surgery: Colectomy for urgent management of ongoing severe colitis/toxic megacolon. Surgery is also for abscess formation and stricture management in those with Crohn's disease. Stricturoplasty is used to preserve the bowel. Drainage of abscesses. Over 2/3rds of those with Crohn's will require surgery at some point.

Other agents

• Azathioprine as a steroid-sparing agent
• Sulfasalazine - very minor effectiveness in Crohn's disease
• Elemental diets - effective as steroids but unpalatable
• Methotrexate - used in those with active Crohn's disease resistant to steroids. Given once weekly.
• Ciclosporin [US Cyclosporine] - severe acute disease who fail to settle with IV steroids
• Infliximab/Adalimumab: Anti TNF monoclonal antibody given as infusion for Crohn's disease which fails to respond to steroids. Useful for those with fistulas. Infusions are given every 8 weeks.
• Metronidazole - Useful in perianal Crohn's disease. Has antibacterial and immunosuppressive actions
• Dietician involvement to maximise nutrition
• Specialist nurse advice to support and inform and educate patient and help coordinate treatment