The case of the missing appendix: a case report of appendiceal intussusception at the site of colonic mullerianosis.

Right lower quadrant pain is a symptom with an exceptionally broad differential diagnosis. Intussusception of the appendix is a very uncommon condition with many manifestations. Additionally, the pathologic finding of ectopic presence of a mixture of at least two mullerian-derived tissue components is rare. This report presents the case of a 49-year-old woman who presented twice with acute right lower abdominal pain. Diagnosis of appendiceal inversion was made surgically. Pathologic examination of the specimen identified extensive endometriosis, endosalpingiosis and endocervicosis of the colon wall. Appendiceal intussusception and colonic mullerianosis, present together, are discussed, and recommendations for the diagnosis and treatment of appendiceal intussusception are discussed.