Clinical Scenario:
A 13-year-old boy is admitted with a 6-week history of progressively worsening diarrhea. He is passing 10–12 bloody stools daily, including nocturnal stools, associated with urgency and tenesmus. He has lost 6 kg over the past two months and complains of fatigue. Examination reveals pallor, tachycardia (HR 118/min), and mild diffuse abdominal tenderness. His BMI is below the 5th percentile.
Investigations:
Hemoglobin: 8.5 g/dL
ESR: 65 mm/hr
CRP: 48 mg/L
Serum albumin: 2.6 g/dL
Stool cultures: Negative
Fecal calprotectin: >2000 μg/g
Colonoscopy demonstrates continuous circumferential inflammation extending from the rectum to the splenic flexure with spontaneous mucosal bleeding and multiple deep ulcerations.
He is started on intravenous hydrocortisone. After 5 days of therapy, he continues to pass 9–10 bloody stools daily and his Pediatric Ulcerative Colitis Activity Index (PUCAI) score remains 75.
What is the most appropriate next step in management?
A. Azathioprine
B. Infliximab
C. Mesalamine (oral and rectal)
D. Methotrexate
E. Oral prednisolone
Correct answer & Explanation:
Correct Answer: B. Infliximab
Discussion: Ulcerative colitis
This child has Acute Severe Ulcerative Colitis (ASUC) as suggested by:
Frequent bloody diarrhea (>6/day)
Nocturnal stools
Urgency and tenesmus
Significant weight loss
Anemia and hypoalbuminemia
Elevated inflammatory markers
Colonoscopy showing continuous disease beginning from the rectum without skip lesions
The patient was appropriately started on intravenous hydrocortisone, which is first-line treatment for ASUC.
A PUCAI score ≥65 after 5 days of intravenous corticosteroids indicates steroid-refractory acute severe colitis. In such patients, escalation to rescue therapy is required.
Infliximab is currently the preferred rescue therapy in most pediatric centers and is highly effective in avoiding urgent colectomy.
Why the Other Options Are Incorrect
A. Azathioprine
Slow onset of action (several weeks to months).
Used for maintenance of remission, not induction in acute severe disease.
C. Mesalamine (oral and rectal)
Appropriate for mild-to-moderate ulcerative colitis.
Inadequate for steroid-refractory ASUC.
D. Methotrexate
Limited role in ulcerative colitis and not recommended as rescue therapy.
E. Oral prednisolone
Failure of IV corticosteroids indicates need for escalation, not continuation of steroid therapy by another route.
Key Examination Pearl
A child with acute severe ulcerative colitis who has a PUCAI ≥65 after 3–5 days of intravenous hydrocortisone has steroid-refractory disease, and the single best next treatment is infliximab. Azathioprine should never be chosen as rescue therapy because of its delayed onset of action.
