Appendiceal Endosalpingiosis: A Rare Cause of Appendicitis-Like Presentation

We report a case of a 55-year-old female who presented to the emergency department with symptoms of appendicitis. Imaging demonstrated appendiceal mucocele and possible early appendicitis. She underwent a laparoscopic appendectomy and subsequent histopathology demonstrated irregular fibrosis of the appendiceal wall as a result of endosalpingiosis with secondary mucocele formation. In this report, we present an exceedingly rare case of endosalpingiosis causing an appendicitis mimic. Although endosalpingiosis is typically considered a benign incidental finding, appendiceal involvement can mimic acute appendicitis, as in this case, and may be associated with an increased risk of gynecologic malignancy. The patient was followed up with the gynecological team due to this malignancy risk and is planned for laparoscopic oophorectomy, with the final histopathology diagnosis being appendiceal endosalpingiosis with secondary mucocele.