What is the recommended treatment for a patient with Crohn's disease?

Treatment of Crohn's Disease

For patients with moderate to severe Crohn's disease or those with high-risk features (stricturing/penetrating disease, perianal fistulas, age <40, or requiring steroids at diagnosis), initiate anti-TNF biologic therapy (infliximab or adalimumab) immediately as first-line treatment. 1, 2, 3

Disease Severity Assessment and Risk Stratification

Before selecting treatment, categorize disease severity as mild, moderate, or severe based on clinical symptoms, inflammatory markers (CRP, fecal calprotectin), and extent of disease involvement. 1, 4 Determine disease location (ileal, colonic, or ileocolonic) and pattern (inflammatory, stricturing, or penetrating) as this directly impacts treatment selection. 1, 4

High-risk features that mandate immediate biologic therapy include: 1

• Stricturing or penetrating disease behavior
• Perianal fistulas
• Age under 40 years at diagnosis
• Need for corticosteroids at initial presentation
• Extensive disease involvement

Treatment Algorithm by Disease Severity

Mild to Moderate Disease (Low-Risk Patients)

For mild to moderate disease limited to the ileum and/or right colon (ascending colon), use oral budesonide 9 mg once daily for 8 weeks as first-line therapy. 1, 4, 5 Budesonide achieves similar remission rates to conventional corticosteroids (51% vs 52.5% at 8 weeks) but with significantly fewer systemic side effects. 4, 5

For mild to moderate colonic Crohn's disease, sulfasalazine is a reasonable option, though it shows only modest benefit over placebo. 4, 6, 7 Sulfasalazine is inferior to corticosteroids but may be appropriate for patients wishing to avoid steroid side effects. 7

Important caveat: Other mesalamine/aminosalicylate formulations (including 5-ASA products) are NOT effective for Crohn's disease and should not be used for either induction or maintenance therapy. 1, 4, 8, 7 Despite common use in practice, high-quality evidence demonstrates they are ineffective. 8

Moderate to Severe Disease

For moderate to severe disease, initiate systemic corticosteroids immediately: 1, 4

• Outpatients: Oral prednisone 40-60 mg/day 1, 4
• Hospitalized patients: IV methylprednisolone 40-60 mg/day (typically 40 mg every 8 hours) 1

Evaluate response to corticosteroids at 2-4 weeks (outpatients) or within 1 week (hospitalized patients). 1, 4 If inadequate response, switch immediately to biologic therapy. 1, 4

Taper prednisone gradually over 8 weeks once remission is achieved, as more rapid tapering increases relapse risk. 1 Budesonide should be tapered over 1-2 weeks. 4

Biologic Therapy (First-Line for High-Risk or After Steroid Failure)

Anti-TNF agents (infliximab or adalimumab) are the preferred biologic therapy for moderate to severe Crohn's disease. 1, 5, 2, 3

FDA-approved dosing for adalimumab (Humira): 2

• Adults: 160 mg on Day 1 (single dose or split over 2 days), then 80 mg on Day 15, then 40 mg every other week starting Day 29
• Pediatrics ≥40 kg: Same as adult dosing
• Pediatrics 17-40 kg: 80 mg Day 1,40 mg Day 15, then 20 mg every other week

FDA-approved dosing for infliximab (Remicade/Renflexis): 3

• Standard induction dosing per product labeling for moderate to severe Crohn's disease

Evaluate response to anti-TNF therapy at 8-12 weeks; if no response by week 14, discontinue and switch to alternative biologic. 4

Alternative biologics for anti-TNF failures or contraindications: 1, 4

• Vedolizumab: Evaluate response at 10-14 weeks 1
• Ustekinumab: Evaluate response at 6-10 weeks 1, 4
• Guselkumab: Can be considered as alternative 1

Maintenance Therapy

Critical principle: Corticosteroids must NEVER be used for maintenance therapy under any circumstances. 1, 4, 5 They are completely ineffective for maintaining remission and cause significant toxicity with long-term use. 1

For patients who achieve remission with biologic therapy, continue the same biologic indefinitely for maintenance. 1, 4, 5

For patients who achieve remission with corticosteroids but are not on biologics, initiate maintenance therapy with: 1, 4

• Thiopurines (azathioprine 2-2.5 mg/kg/day or 6-mercaptopurine 1-1.5 mg/kg/day): Recommended for steroid-dependent patients or those with adverse prognostic factors 1, 4
• Parenteral methotrexate: Consider only if thiopurines failed, not tolerated, or contraindicated 1, 4

Combination therapy (anti-TNF plus thiopurine) is more effective than monotherapy for maintaining remission, but must be balanced against increased infection risk, particularly in young males (hepatosplenic T-cell lymphoma risk). 1, 5

Monitoring and Follow-Up

Use objective markers (endoscopy, CRP, fecal calprotectin, imaging) for monitoring, as symptoms poorly correlate with inflammation. 1 Regular monitoring is crucial because up to 50% of patients require surgery within 10 years of diagnosis. 1

Therapeutic drug monitoring should be used to optimize anti-TNF dosing in patients losing response. 5

Critical Pitfalls to Avoid

• Never use mesalamine/5-ASA products for Crohn's disease despite their common use—they are ineffective 1, 4, 8
• Never use corticosteroids for maintenance therapy—they don't work and cause harm 1, 4, 5
• Avoid long-term opioid use—associated with poor outcomes in IBD 1
• Do not use probiotics, omega-3 fatty acids, marijuana, or naltrexone—no evidence of benefit 1
• Do not delay biologic therapy in high-risk patients—early intervention prevents complications 1