What are the initial treatment recommendations for an adult diagnosed with colitis?

Initial Treatment Recommendations for Adults with Colitis

For adults diagnosed with colitis, the initial treatment should focus on 5-aminosalicylates (5-ASA) for mild to moderate disease, while moderate to severe disease requires corticosteroids or biologic agents depending on disease severity. 1

Assessment and Classification

• Determine the type and severity of colitis (ulcerative colitis vs. Crohn's colitis vs. infectious colitis) through clinical presentation, laboratory tests, stool studies, and endoscopic findings 2, 3
• Evaluate disease activity based on stool frequency, rectal bleeding, fecal urgency, and endoscopic findings (vascular pattern, bleeding, erosions, ulcers) 3
• Consider fecal calprotectin as a suitable disease activity marker 3

Treatment Algorithm for Ulcerative Colitis

Mild to Moderate Disease

• First-line: Oral and rectal 5-aminosalicylates (mesalazine 4g/day) 1, 2
• For distal colitis: Combination of topical mesalazine and oral mesalazine provides better relief than either alone 1
• Treat proximal constipation with stool bulking agents or laxatives if present 1

Moderate to Severe Disease

• For patients failing 5-ASA therapy or presenting with moderate-severe disease: Oral corticosteroids (prednisolone 40mg daily) 1
• The AGA suggests early use of biologic agents with or without immunomodulator therapy rather than gradual step-up after failure of 5-aminosalicylates 1
• Biologic options include TNF-α antagonists (infliximab, adalimumab, golimumab), vedolizumab, ustekinumab, or JAK inhibitors (tofacitinib, upadacitinib) 1
• For biologic-naive patients, infliximab or vedolizumab are preferred over adalimumab for induction of remission 1
• JAK inhibitors (tofacitinib) should only be used after failure of TNF-α antagonists per FDA recommendations 1

Severe Acute Colitis (Requiring Hospitalization)

• Intravenous methylprednisolone (dose equivalent of 40-60mg/day) 1, 4
• Close monitoring with daily physical examination, vital signs, stool chart, and laboratory tests 1
• Joint management by gastroenterologist and colorectal surgeon 1
• For steroid-refractory disease: Infliximab or cyclosporine as rescue therapy 1, 4
• Subcutaneous heparin to reduce thromboembolism risk 1
• Nutritional support if malnourished 1

Combination Therapy Considerations

• For moderate-severe UC: Consider combining TNF-α antagonists, vedolizumab, or ustekinumab with thiopurines or methotrexate rather than biologic monotherapy 1
• The AGA suggests against using thiopurine monotherapy for induction of remission 1
• The AGA suggests against using methotrexate monotherapy for induction or maintenance of remission 1

Infectious Colitis Considerations

• Standard stool culture should be performed to rule out infectious causes 5
• For suspected infectious colitis with fever and dysentery: Consider empiric treatment with azithromycin 1000mg single dose while awaiting culture results 5
• For C. difficile colitis: Appropriate antibiotics based on severity 5

Maintenance Therapy

• Lifelong maintenance therapy is generally recommended, especially for patients with left-sided or extensive disease 1
• Options include 5-aminosalicylates, azathioprine, or mercaptopurine 1
• In patients who achieve remission with biologics and/or immunomodulators, the AGA suggests against continuing 5-aminosalicylates for maintenance 1

Important Caveats

• Patients should be informed about treatment options and prognosis, including a 25-30% chance of needing colectomy in severe cases 1
• Regular monitoring for disease activity and treatment response is essential 3
• Consider early surgical consultation for patients with severe disease not responding to medical therapy 1, 4
• Recognize that acute onset UC can be difficult to distinguish from infectious colitis, but treatment with corticosteroids should not be delayed while awaiting stool microbiology results 1