A 28-year-old man from Bihar presents with weight loss, evening fever, right iliac fossa pain, and loose stools for four months. Colonoscopy shows transverse ulcers and a deformed ileocecal valve. Biopsy of the ileocecal region shows granulomatous inflammation. Which single histological finding most strongly favours intestinal tuberculosis over Crohn's disease?

• A Transmural non-caseating epithelioid granulomas
• B Non-necrotizing granulomas away from areas of ulceration
• C Confluent linear ulcers along the mesenteric border
• D Acid-fast bacilli demonstrated on Ziehl-Neelsen staining ✓

Explanation

In India, distinguishing intestinal tuberculosis from Crohn's disease is mandatory because anti-TNF therapy given for misdiagnosed Crohn's can reactivate tuberculosis. Demonstrating acid-fast bacilli on Ziehl-Neelsen stain, or caseating granulomas, confirms tuberculosis. Non-caseating granulomas remote from ulcers, transmural lymphoid aggregates, and longitudinal serpiginous ulcers favour Crohn's disease. Confluent linear mesenteric-border ulcers are actually a Crohn pattern, while tuberculosis classically gives transverse ulcers with a pulled-up caecum.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.