Q: "String sign" can be seen in which of the following diseases?

A) Esophageal Achalasia
B) Ulcerative Colitis
C) Crohn Disease
D) Perforated duodenal ulcer
E) Necrotizing Pancreatitis


Answer: C

Crohn's Disease causes severe ulceration and consequently causes spasm of the terminal ileum. If contrast is given, terminal ileum appears like a string. Though it can be seen in other similar conditions but is considered to be the hallmark of Crohn disease.