This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Inflammatory Bowel Diseases, Subject name: Medicine
Cobble stoning of colon is seen in : 
Select and explain. 
A. Crohn's disease, B. Ulcerative colitis, C. Ischemic colitis, D. Amoebic colitis
A: Crohn's disease
Answer: A: Crohn's disease 
Explanation: Ans. (a) Crohn's diseaseRef: Harrison 19th ed. /1951-52CD is a transmural process. Endoscopically, aphthous or small superficial ulcerations characterize mild disease; in more active disease, stellate ulcerations fuse longitudinally and transversely to demarcate islands of mucosa that frequently are histologically normal.This "cobblestone" appearance is characteristic of CD, both endoscopically and by barium radiographyUlcerative ColitisCrohn DiseaseOnly colon involvedPanintestinalContinuous inflammation extending proximally from rectumSkip-lesions with intervening normal mucosaInflammation in mucosa and submucosa onlyTransmural inflammationNo granulomasNoncaseating granulomasPerinuclear ANCA (pANCA) positiveASCA positiveBleeding (common)Bleeding (uncommon)Fistulae (rare)Fistulae (common)