Inflammatory bowel disease is the umbrella term for the two main diseases that cause inflammation of the GI tract: ulcerative colitis and Crohn’s disease. They both involve inflammation of the walls of the GI tract and are associated with periods of remission and exacerbation.
Crohn’s versus Ulcerative Colitis
Crohn’s and ulcerative colitis have features that are distinct from each other. These features are often tested in exams.
Crohn’s (crows NESTS)
- N – No blood or mucus (these are less common in Crohns.)
- E – Entire GI tract
- S – “Skip lesions” on endoscopy
- T – Terminal ileum most affected and Transmural (full thickness) inflammation
- S – Smoking is a risk factor (don’t set the nest on fire)
Crohn’s is also associated with weight loss, strictures and fistulas.
Ulcerative Colitis (remember U – C – CLOSEUP)
- C – Continuous inflammation
- L – Limited to colon and rectum
- O – Only superficial mucosa affected
- S – Smoking is protective
- E – Excrete blood and mucus
- U – Use aminosalicylates
- P – Primary sclerosing cholangitis
Presentation
Suspect inflammatory bowel disease in children and teenagers presenting with perfuse diarrhoea, abdominal pain, bleeding, weight loss or anaemia. They may be systemically unwell during flares, with fevers, malaise and dehydration.
Extra-Intestinal Manifestations
Patients with inflammatory bowel disease can develop signs outside the gastrointestinal system that examiners like to test. It is worth remembering these extra-intestinal manifestations:
- Finger clubbing
- Erythema nodosum
- Pyoderma gangrenosum
- Episcleritis and iritis
- Inflammatory arthritis
- Primary sclerosing cholangitis (ulcerative colitis)
Testing
Blood tests for anaemia, infection, thyroid, kidney and liver function. A raised CRP indicates active inflammation.
Faecal calprotectin is released by the intestines when inflamed. It is a useful screening test and is more than 90% sensitive and specific for IBD in adults.
Endoscopy (OGD and colonoscopy) with biopsy is the gold standard investigation for diagnosis of IBD.
Imaging with ultrasound, CT and MRI can be used to look for complications such as fistulas, abscesses and strictures.
General Management
Any child presenting with symptoms suggestive of inflammatory bowel disease should be referred to secondary care for specialist assessment and management. They will be closely followed up by the multi-disciplinary team. This team includes paediatricians, specialist nurses, pharmacists, dieticians and surgeons if necessary.
It is essential to monitor the growth and pubertal development in children with inflammatory bowel disease, particularly when they are having exacerbations or being treated with steroids.
Management involves a combination of inducing remission during flares and maintaining remission when well. It is essential to monitor and supporting growth and development, and patients are likely to need input from a dietician.
Management of Crohn’s
This section is based on NICE guidelines last updated May 2019. Please see the full guidelines and talk to seniors before treating patients.
Inducing Remission
First line are steroids (e.g. oral prednisolone or IV hydrocortisone).
If steroids alone don’t work, consider adding immunosuppressant medication under specialist guidance:
- Azathioprine
- Mercaptopurine
- Methotrexate
- Infliximab
- Adalimumab
Maintaining Remission
Treatment is tailored to individual patients based on risks, side effects, nature of the disease and patient preference. It is reasonable not to take any medications whilst well.
First line:
- Azathioprine
- Mercaptopurine
Alternatives:
- Methotrexate
- Infliximab
- Adalimumab
Surgery
When the disease only affects the distal ileum it is possible to surgically resect this area to prevent further flares. Crohn’s typically involves the entire GI tract. Surgery can also be used to treat strictures and fistulas secondary to Crohn’s disease.
Management of Ulcerative Colitis
This section is based on NICE guidelines last updated May 2019. Please see the full guidelines and talk to seniors before treating patients.
Inducing Remission
Mild to moderate disease
- First line: aminosalicylate (e.g. mesalazine oral or rectal)
- Second line: corticosteroids (e.g. prednisolone)
Severe disease
- First line: IV corticosteroids (e.g. hydrocortisone)
- Second line: IV ciclosporin
Maintaining Remission
- Aminosalicylate (e.g. mesalazine oral or rectal)
- Azathioprine
- Mercaptopurine
Surgery
Ulcerative colitis usually only affects the colon and rectum. Therefore, removing the colon and rectum (panproctocolectomy) will remove the disease. The patient is then left with either a permanent ileostomy or something called an ileo-anal anastomosis (J-pouch). This is where the ileum is folded back on itself and fashioned into a larger pouch that functions like a rectum. This “J-pouch” is then attached to the anus and collects stools prior to the person passing a motion.
Last updated August 2019