Ulcerative colitis

What is ulcerative colitis?

Ulcerative colitis (UC) belongs, together with Crohn’s disease, to the inflammatory bowel diseases. These are chronic inflammations of unknown cause with an autoimmune component. Frequency: 20-130 per 100,000 people (more common in men); the number of new cases is rising, with peaks in the second and seventh decades of life. It is more common in the developed Western world and in families where inflammatory bowel disease already occurs. UC is confined to the large bowel; it is continuous rather than segmental and, unlike Crohn’s disease, does not affect the full thickness of the bowel wall. Causes: an inflammatory process of unknown origin, in which external factors (infections, allergic environmental factors) and internal factors (genetics, association with other inherited conditions, cow’s milk sensitivity in childhood) play a role, together with an immunological background.

What are the symptoms?

diarrhoea (6-12 times a day), stools containing pus or blood

increased bowel activity and urgency (tenesmus)

delayed growth (less common)

rarely, a severe acute form (toxic megacolon) with:

abdominal bloating

tachycardia (fast heartbeat),

fever,

absent bowel sounds,

this can easily lead to perforation of the large bowel, and sepsis and heavy bleeding can also occur.

Symptoms outside the bowel:

– immune-related conditions,

– primary sclerosing cholangitis,

– chronic active hepatitis,

– eye and skin involvement.

How is it diagnosed?

Diagnosis: medical history, physical examination (including rectal examination), blood tests, colonoscopy, tissue biopsy, barium X-ray and barium enema to detect ulcers and pseudopolyps, and CT scan. Differential diagnosis: Crohn’s disease, indeterminate colitis (where Crohn’s and UC cannot be distinguished), appendicitis, infectious colitis (stool culture), and in infants allergic colitis caused by milk allergy. Phases: acute phase, dominated by inflammation and ulcers (shallower than in Crohn’s disease), which can be very severe (toxic megacolon, sepsis); regenerative (chronic) phase, with incomplete, pseudopolypous healing and inflammatory tissue growth; ‘healed’ phase, which can be completely symptom-free for years, although a flare-up is always possible. Complications: ulcerative colitis carries an increased risk of bowel cancer.

What treatments are available?

Induction treatment: mild UC, 5-ASA by mouth and/or rectally; moderately severe UC, 5-ASA by mouth and/or rectally, with or without oral and/or rectal steroids (budesonide); severe UC, hospital admission, supportive care (fluids, electrolytes and blood proteins by infusion), oral or intravenous steroids with or without rectal steroids and oral or rectal 5-ASA, plus antibiotics; fulminant UC (sudden, rapidly progressing, severe condition), intensive care, supportive care, intravenous nutrition and medication, and surgery to remove the affected section of bowel if there is no improvement within 72-96 hours or if complications develop; toxic megacolon, treated as for fulminant UC, with removal of the colon (colectomy) if there is no improvement within 24-48 hours or if complications are present. Maintenance treatment: 5-ASA, sulfasalazine with folic acid, steroids (at the lowest necessary dose, then tapered), azathioprine, methotrexate, ciclosporin and mycophenolate mofetil (when steroids do not work or to reduce steroid use), colectomy (for chronic active disease or significant side effects of medication), prevention of osteoporosis (calcium, vitamin D, alendronate, risedronate), prompt treatment of relapses after excluding infection, and bowel cancer screening every 2-3 years once UC has been present for 8-10 years. Surgical treatment: the whole lining of the large bowel needs to be removed, which usually requires a permanent stoma and has a significant impact on quality of life. Outlook: removal of the colon can be curative.