Ileojejunitis in a pair of identical twins.

A pair of identical twin brothers with identical white and red blood cell antigens and diffuse ileojejunitis is reported. One brother initially presented with granulomatous gastritis, presumably Crohn's disease of the stomach. The relationship of diffuse ileojejunitis to Crohn's disease and the suspected genetic predisposition to develop Crohn's disease are briefly discussed.