Backwash ileitis

Definition: inflammation of the terminal ileum in the context of ulcerative colitis

Epidemiology: affects approximately 10–20% of all patients diagnosed with ulcerative colitis

Localization: typically affects an area a few centimeters proximal to the ileocecal valve

Pathophysiology: The pathological mechanism is not fully understood.

Differential diagnosis: Clinically, backwash ileitis is hardly relevant but its presence makes it harder to differentiate between ulcerative colitis and Crohn disease.