Endometriosis of the duplex appendix: A case report and review of the literature

Abstract

BACKGROUND

Duplication of the appendix is an infrequent congenital malformation with a complex classification. The horseshoe appendix is a subtype of the duplex appendix and is rarely reported in the literature. Endometriosis is a common gynecological disease that rarely occurs in the appendix. Moreover, horseshoe appendix combined with endometriosis has not been previously reported.

CASE SUMMARY

Here, we describe a 44-year-old woman who was admitted with a 1-d history of migratory lower right quadrant pain. Physical examination was consistent with the signs of acute appendicitis. The patient underwent an emergency exploratory laparotomy. The distal tip of the appendix was in contact with the cecum by another base, or “horseshoe appendix”. In addition, a small intestinal mass and an ovarian mass were identified. Subsequently, appendectomy, partial resection of the small intestine, and right oophorectomy were successively performed. The histopathology confirmed the diagnosis of acute inflammation of the duplex appendix with endometriosis, small intestine endometriosis, and ovarian endometriosis.

CONCLUSION

Surgeons need to be aware of the possibility of the duplex appendix when performing an appendectomy, and this study emphasizes the importance of exploring the entire abdomen.

Keywords: Duplex appendix; Horseshoe appendix; Endometriosis; Appendectomy; Case report

Core tip: We describe a patient with endometriosis of the duplex appendix, small intestine, and ovary. There are no similar cases reported. Currently, the diagnosis of duplex appendix and endometriosis is difficult before surgery. Our case suggests that serum carbohydrate antigen 125 levels and fecalith of the appendix may be useful signs for the diagnosis of endometriosis and duplex appendix, respectively. However, the most important procedure is the careful exploration of the abdominal cavity during surgery. Serious legal disputes can occur due to neglecting another infected appendix or not carefully exploring other parts of the abdominal cavity.