Cobble stoning of intestine with string sign of kantor is seen in:

Ans. A. Crohn's disease* Cobble stone mucosa is appearance of the intestinal mucosa in Crohn's disease to the endoscopist, Cobblestoning refers to the uniform nodules-due to the sub-mucosal fibrosis.* String sign of Kantor is due to involvement of the terminal ileum in Crohn's disease.* It is caused by severe spasm due to irritability of the loop producing the appearance of a frayed cotton string.* Subsequently the wall of the ileum may become fibrotic and the lumen fixed in diameter.