The Case of Isolated Appendiceal Endometriosis Mimicking Appendicitis

Endometriosis is the presence of endometrial tissue outside the uterine cavity. It is mostly seen in the pelvis but can also affect the extrapelvic areas of the body. Gastrointestinal (GI) tract is the most frequently affected extrapelvic site and rarely involves the appendix. When it occurs, may mimick appendicitis. We present a childbearing-age woman suffering from right lower quadrant (RLQ) pain. Her complaint was repeating cyclically for 8 months. Abdominal ultrasound (US) disclosed wall thickening at tip of the appendix and small amount of fluid around it, suggesting distal appendicitis. Computed tomography (CT) depicted approximately a 1 cm nodulary mass on tip of the appendix. Then appendectomy was performed and histopathological examination yielded appendiceal endometriosis (AE). She was recovered well and free of her symptom. This report emphasizes the isolated appendiceal endometriosis, which can cause right lower quadrant pain and mimick appendicitis.