The definition below was copied from the internet. My comments are added in red.
Treatment consists of steroids and removal of sensitizing agent.
There is a characteristic 'saw tooth' appearance to the small bowel, especially the jejunum. The bowel is typically rigid, but returns to normal following therapy. Multiple nodules may be seen if there is predominantly submucosal infiltration. Chronically, the antrum becomes contracted with a cobblestone appearance. On CT, there is thickening and nodularity to the folds of the stomach and proximal small bowel.