Anal canal duplication in children: a monocentric experience of 12 cases

Anal canal duplication is a rare malformation characterized by a second perineal opening positioned behind the anus, which is generally observed at 6 o'clock in the lithotomy position. The purpose was to describe six new cases of anal canal duplication (in addition to our previously reported series of six patients) with the aim of providing further clinical information about this anomaly.

We described 6 new cases of anal canal duplication in terms of symptoms, anatomical disposition, imaging results, and histopathology. Clinical details of these cases and those already reported (n = 12) were summarized and compared to existing literature.

A total of 12 cases were reported over 34 years. 17% of the patients were male, constituting the only subgroup to present a communication with the digestive tract. A single patient, diagnosed at 12 years, was symptomatic. Half of the patients had at least one associated malformation. All patients underwent surgery, either with a posterior sagittal or perineal approach.

Diagnosis of anal canal duplication should be suspected when a perineal opening positioned behind the anus is present, and necessitates further exploration by a comprehensive clinical examination and imaging. Surgery is always required, typically performed via a posterior sagittal approach. The postoperative course is usually uncomplicated.