Treatment Approach for Inflammatory Bowel Disease
Treatment of IBD must be stratified by disease type (ulcerative colitis versus Crohn's disease), anatomic location, and severity, with ulcerative colitis responding best to aminosalicylates and Crohn's disease requiring corticosteroids or biologics for moderate-to-severe presentations. 1, 2, 3
Disease-Specific Treatment Algorithms
Ulcerative Colitis Treatment Strategy
For distal/left-sided ulcerative colitis, combination therapy with topical mesalazine ≥1g daily PLUS oral mesalazine 2-4g daily is superior to either agent alone and represents first-line therapy. 1, 3 Topical mesalazine is more effective than topical corticosteroids and should be preferred. 1 Once-daily dosing is as effective as divided doses and improves adherence. 3
For extensive ulcerative colitis, initiate oral mesalazine 2-4g daily or balsalazide 6.75g daily. 2, 3 If inadequate response occurs, escalate to oral prednisolone 40mg daily. 2, 3
For severe ulcerative colitis (bloody stool frequency ≥6/day plus tachycardia >90/min, temperature >37.8°C, hemoglobin <10.5 g/dL, or ESR >30 mm/h), immediate hospitalization for intravenous therapy is required. 1 This requires joint medical-surgical management with daily physical examination, vital signs four times daily, stool charting, and laboratory monitoring (FBC, ESR/CRP, electrolytes, albumin) every 24-48 hours. 4 Intravenous fluid and electrolyte replacement, blood transfusion to maintain hemoglobin >10 g/dL, and subcutaneous heparin for thromboembolism prophylaxis are essential. 4
Crohn's Disease Treatment Strategy
For mild ileocolonic Crohn's disease, high-dose mesalazine 4g daily may be sufficient initial therapy. 4, 3 For isolated ileocaecal disease with moderate activity, budesonide 9mg daily is appropriate, though marginally less effective than prednisolone. 4, 3
For moderate-to-severe Crohn's disease, advanced therapy such as biologics or small molecules as first-line treatment improves long-term disease control. 2, 3 Alternatively, oral prednisolone 40mg daily is appropriate, reduced gradually over 8 weeks to prevent early relapse. 4, 1, 3 More rapid steroid reduction is associated with early relapse and should be avoided. 4, 1
For fistulizing and perianal Crohn's disease, metronidazole 400mg three times daily and/or ciprofloxacin 500mg twice daily are appropriate first-line treatments for simple perianal fistulae. 4 Infliximab (three infusions of 5mg/kg at weeks 0,2, and 6) should be reserved for patients whose fistulae are refractory to other treatment and used as part of a strategy including immunomodulation and surgery. 4, 5 Among patients with fistulizing disease, 68% receiving 5mg/kg infliximab achieved fistula response (≥50% reduction in draining fistulas) versus 26% with placebo. 5
Maintenance Therapy
Lifelong maintenance therapy is generally recommended for all ulcerative colitis patients, especially those with left-sided or extensive disease. 4, 3 Aminosalicylates (mesalazine, balsalazide, olsalazine) reduce relapse risk and may reduce colorectal cancer risk by up to 75% in extensive ulcerative colitis. 2, 3
For Crohn's disease maintenance, azathioprine 1.5-2.5mg/kg/day or mercaptopurine 0.75-1.5mg/kg/day are effective second-line options. 4, 2, 3 Corticosteroids are not recommended for maintenance therapy in Crohn's disease. 2
Systemic corticosteroids should be used for no longer than 8 weeks, and budesonide for mild ileocaecal disease only with a maximum duration of 12 weeks. 2
Biologic Therapy Escalation
When conventional immunosuppressive therapy (azathioprine, 6-mercaptopurine, methotrexate) fails or is not tolerated, biologics represent the next line in a step-up approach. 4 Anti-TNF agents (infliximab, adalimumab, golimumab) are usually the first biologic prescribed due to lower costs with biosimilars and good effectiveness/safety profile. 4 Next-line biologicals include vedolizumab (anti-integrin) and ustekinumab for Crohn's disease blocking the interleukin 12/23 pathway. 4 Tofacitinib (JAK inhibitor) was recently approved for ulcerative colitis treatment. 4
Surgical Considerations
Surgery should be considered for Crohn's disease patients who have failed medical therapy and may be appropriate as primary therapy for limited ileal or ileocaecal disease. 4, 3 Conservative resections of macroscopic disease only should be performed. 3 The risk of first Crohn's disease surgery after 10 years decreased from 44% to 21% in the last two decades, likely due to anti-TNF therapy and improved multidisciplinary management. 4
For ulcerative colitis, surgery is indicated for disease not responding to intensive medical therapy, dysplasia/carcinoma, or poorly controlled disease. 3 Patients with severe ulcerative colitis should be informed of a 25-30% chance of needing colectomy. 4 The 5-, 10-, 15-, and 20-year cumulative colectomy rates after diagnosis are 4.1%, 6.4%, 10.4%, and 14.4%, respectively. 4
Critical Pitfalls to Avoid
Never use monotherapy when combination therapy is indicated for distal ulcerative colitis—topical plus oral aminosalicylates are more effective than either alone. 1 Avoid rapid steroid tapering, as prednisolone should be reduced gradually over 8 weeks to prevent early relapse. 4, 1 Do not use corticosteroids for maintenance therapy in Crohn's disease. 2 Avoid infliximab in Crohn's disease patients with obstructive symptoms. 4
Surveillance and Multidisciplinary Care
Colonoscopy is recommended after 8-10 years to re-evaluate disease extent, with surveillance decisions individualized based on patient risk factors, particularly for extensive or left-sided disease. 2, 3 A multidisciplinary team including gastroenterologists with IBD expertise, colorectal surgeons, and other specialists is essential for optimal IBD care. 2