Endometriosis of the appendix resulting in perforated appendicitis

Endometriosis is a relatively common disease among women of reproductive age. However, gastrointestinal endometriosis is rare and endometriosis of the appendix resulting in perforated appendicitis is even rarer. We experienced a case of endometriosis of the appendix manifesting as panperitonitis caused by perforation of the appendix. The patient was a 35-year-old woman who was hospitalized with an acute abdomen. She was diagnosed with panperitonitis and underwent urgent laparotomy. When perforation of the appendix was detected, appendectomy and intraperitoneal drainage were performed. Pathological examination revealed endometriosis extending from the muscularis propria to the subserosa, and a diagnosis of endometriosis of the appendix was made. We consider the relevant literature describing the mechanism by which endometriosis of the appendix occurs, and the association between endometriosis of the appendix and acute appendicitis.