A Case of Small Bowel Obstraction Caused by Extra-gastrointestinal Anisakiasis Treated Laparoscopically

A 52-year-old man visited our hospital because of 2-week history of fever and diarrhea and right lower quadrant abdominal pain occurred 3 days before his visit. Abdominal CT scan showed dilatation of the small intestine and inflammatory findings and whirl sign around the jejunum. He was admitted to our hospital to observe the clinical course with a diagnosis of intestinal obstruction. As symptomatic remission was not attained by placing a long tube, exploratory laparoscopic operation was performed for diagnostic and therapeutic purposes on the 14 th hospital day. During the operation, we found an extramurally growing tumor in an intestinal mesentery where was 100 cm distant from the Treiz ligament and adhesions in-volving the tumor, abdominal wall, another intestinal mesentery, and greater omentum. A loop of the distal small bowel was incarcerated in a space constituted with the adhesions. We dissected the adhesions and resected the tumor. Pathological findings showed that the extramurally growing tumor was an eosin-ophilic suppurative granuloma. An Anisakis larva was found within the granuloma. For these findings, this case was diagnosed as extra-gastrointestinal anisakiasis. Although small bowel obstruction caused by small bowel anisakiasis is not uncommon, small bowel obstruction caused by extra-gastrointestinal anisakiasis like our case is rarely reported.