A 28-year-old woman from Delhi presents with a 6-month history of bloody diarrhoea, abdominal cramping, and tenesmus. She has had 6–8 bowel movements daily with visible blood and mucus. Physical examination reveals mild abdominal tenderness over the left lower quadrant. Laboratory investigations show haemoglobin 9.2 g/dL, serum albumin 3.1 g/dL, and CRP 8.5 mg/dL. Colonoscopy reveals continuous mucosal inflammation limited to the rectum and sigmoid colon with loss of haustra and a granular mucosa. Which of the following is the most appropriate next step in management?

Explanation

## Clinical Diagnosis This patient has **ulcerative colitis (UC)** with the following diagnostic features: - Continuous mucosal inflammation limited to rectosigmoid colon - Loss of haustra ("lead pipe" appearance) - Granular mucosa - Bloody diarrhoea with tenesmus - Mild systemic inflammation (CRP 8.5 mg/dL, mild anaemia, hypoalbuminaemia) ## Disease Severity Assessment **Key Point:** This patient has **mild-to-moderate UC** based on: - 6–8 stools/day (mild: <4; moderate: 4–6; severe: >6 with systemic symptoms) - Haemoglobin >8.5 g/dL (no severe anaemia) - CRP <10 mg/dL (no severe inflammation) - Haemodynamically stable ## First-Line Management of Mild-to-Moderate UC **High-Yield:** The induction therapy for mild-to-moderate UC is **5-ASA ± topical corticosteroids**: | Agent | Role | Dosing | |-------|------|--------| | 5-ASA (mesalamine) | First-line induction & maintenance | 2–4 g/day divided doses | | Topical corticosteroids (hydrocortisone enema/foam) | Adjunct for distal disease | Daily or BD | | Oral corticosteroids | Reserved for moderate-severe or inadequate response | 0.5–1 mg/kg/day prednisolone | | Immunosuppressants (azathioprine, 6-MP) | Steroid-sparing maintenance | Not first-line for induction | | Biologics (TNF-α inhibitors) | Moderate-severe or steroid-dependent | Not first-line induction | **Clinical Pearl:** Rectosigmoid disease (proctitis/proctosigmoiditis) responds exceptionally well to topical therapy — 5-ASA enemas or corticosteroid foams achieve remission in >70% of cases within 2–4 weeks. ## Why This Approach? 1. **Efficacy:** 5-ASA + topical corticosteroids induce remission in 60–80% of mild-to-moderate UC 2. **Safety:** Minimal systemic absorption of topical agents; 5-ASA is well-tolerated 3. **Stepwise escalation:** If inadequate response after 2–4 weeks, add oral corticosteroids or consider immunosuppressants 4. **Maintenance:** 5-ASA continued indefinitely reduces relapse risk by ~50% ## Why Not the Other Options? **Infliximab (Option 0):** Reserved for: - Moderate-to-severe disease failing 5-ASA + corticosteroids - Steroid-dependent or steroid-refractory disease - Extraintestinal manifestations (EIM) - Not first-line for mild-to-moderate disease **Azathioprine monotherapy (Option 2):** - Used as steroid-sparing maintenance, NOT induction - Slow onset (8–12 weeks) - No role in acute induction phase **Surgical resection (Option 3):** - Reserved for: - Fulminant colitis with toxic megacolon - Perforation or uncontrolled bleeding - Chronic intractable disease after maximal medical therapy - Dysplasia/colorectal cancer - This patient is stable and has not failed medical therapy yet [cite:Harrison 21e Ch 319]