This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: NEET 2019, Subject name: Pathology
Which of the following feature distinguishes Crohn's disease from Ulcerative colitis ? 
Select and explain. 
A. Transmural involvement, B. Presence of polyps, C. Mucosal edema, D. Lymphocyte infiltrate
A: Transmural involvement
Answer: A: Transmural involvement 
Explanation: - Crohn's disease is associated with transmural inflammation whereas only superficial layers are involved in ulcerative colitis. Feature Crohn Disease Ulcerative Colitis Macroscopic Bowel region involved Any site of GIT Colon only Distribution Skip lesions Diffuse Stricture Yes Rare Wall appearance Thick Thin Microscopic Inflammation Transmural Limited to mucosa, submucosa Pseudopolyps may/ may not be present Markedly present Ulcers Deep, knife-like Superficial, broad-based Lymphoid reaction Marked Moderate Fibrosis Marked Mild to none Serositis Marked Mild to none Granulomas Yes ( 35%) No Fistulae/sinuses Yes No Clinical Perianal fistula Yes (in colonic disease) No Fat/vitamin malabsorption Yes No Malignant potential With colonic involvment yes Yes Recurrence after surgery Common No Toxic megacolon No Yes All feature may not be present in a single case. TRUE LOVE CLASSIFICATION OF UC.