<prompt> Which of the following is the earliest change in intestine which occurs in Crohns disease?Cobblestone appearanceAphthous ulcerPerforationStricture  <response>: Ref. Robbins Pathology. 9th edition. Page. 800 Crohns DiseasePresent with skip lesionsEarliest lesion Aphthous ulcersCan involve whole of GIT Form oral cavity to amusSmoking is a risk factorFissure, fistula seenStricture seenGross features Creeping pad of fat, Cobblestone appearanceMicroscopy - Non caseating granuloma under microscopy, Transmural inflammation 