Eosinophilic gastroenteritis (EG) is an unusual disorder that is characterized by diffuse or scattered eosinophilic infiltration of the digestive tract. The diagnosis is based on histology obtained by capsule, endoscopic, laparoscopic, or laparotomy biopsy. The eosinophilic infiltration produces thickening of the small bowel wall that can be observed by using sonography. The appearance produces the pseudokidney sign that can be used to guide biopsy. We report the first case of EG diagnosed by percutaneous biopsy under ultrasound guidance.