Eosinophilic gastroenteritis (EG) is a rare condition characterized by patchy eosinophilic inflammation of one or more layers of the gastrointestinal tract with no secondary causes of eosinophilia. EG is a treatable disease and, generally, patients show a positive response to steroid therapy. Sometimes the disease can present as acute abdomen, and appendicular involvement has seldom been described in the course of EG. In our case report we aimed to emphasize how useful gastrointestinal ultrasound is as a valuable tool for diagnosing and monitoring intestinal involvement during EG, avoiding invasive tests and unnecessary surgery.