A Case of Intussusception Caused by Aniakiasis of Small Intestine

Intussusceptions caused by anisakiasis of the small intestine are very rare, and only five cases have been reported in Japan. We report a case of intussusception due to a small intestinal anisakiasis. Patient was a 46-year-old woman who had been suffering from abdominal pain twelve hours after eating raw salmon. Endoscopic examination of upper gastrointestinal tract was considered as gastritis verrucosa and erosive duodenitis. Ultrasonography indicated multiple concentric ring sign in the upper small intestine. CT scan of the abdomen shows layer circle mass in the upper abdomen. Intussusception was manifested by ultrasonography and CT scan of the abdomen. Under a diagnosis of intussusception caused by anisakiasis of the jejunum, an operation was performed. After reducing the intussusception manually, the jejunum was excised with end to end anastomosis. Although diagnosis of intestinal intussusception was previously difficult, recently it has been possible to diagnose it by ultrasonography and computed tomography. It is important to ask the patient details of the food ingested in cases of intussusception caused by intestinal anisakiasis. Furthermore, it is necessary to bear in mind that an inflammatory mass caused by intestinal anisakiasis can induce intussusception.