Rectal duplication as an unusual cause of chronic perianal fistula in an adult: report of a case.

Duplication of the rectum is a rare embryologic event, but it should be considered as a possibility when perianal fistulas and abscesses remain resistant to conventional standard surgical treatment modalities over the long term. We report the case of a 57-year-old woman who underwent many operations over 30 years for persistent perianal fistulas. After radiological assay by computed tomography, fistulography, and barium enema studies, we performed surgery to remove a cystic mass in the retrorectal region, which was subsequently found to be a rectal duplication. The patient had an uneventful postoperative course and has been asymptomatic for 3 years.