A rare differential diagnosis of acute appendicitis: Appendiceal endometriosis

Endometriosis is a fairly common entity in women of reproductive age; the most common sites are the ovaries and peritoneal surface. However, involvement of the gastrointestinal tract is uncommon. Endometriosis of the appendix is even rarer and is difficult to diagnose preoperatively. A definitive diagnosis is established by histological examination of the appendix. Here, we report a case of endometriosis of the appendix that manifested as acute appendicitis in a 31 year old woman. After laparoscopic appendectomy, she had a good clinical course without any residual pain postoperatively. We performed 369 appendectomies from 2005 to 2011 and only one (0.27%) case of appendiceal endometriosis was found pathologically.