Anal canal duplication.

Introduction: Anal canal duplication (ACD) is an extremely rare congenital intestinal anomaly. ACD is defined as a second anal orifice located posterior to the true anus ending blindly without connection to the rectum. Usually, there are no other accompanying hindgut pathologies. Patients are often asymptomatic and apply to clinics with their parent's attention. CASE 1: A 9-month-old girl was referred to our clinic because of a second orifice posterior to the true anus. On the physical examination, there was a 3 mm in diameter orifice, about 0.5 cm behind the anus, at 6 o'clock direction on the lithotomy position. Duplicated lumen was checked with a metal catheter; it was about 2 cm in length ending blindly without connection to the rectum. A prediagnosis of ACD was made and the patient was operated. Duplicated segment was excised totally. Postoperative course was uneventful. CASE 2: One-year-old girl was referred to our clinic because of the same complaint. On the physical examination, there was a 2 mm in diameter orifice, about 0.3 cm behind the anus, at 6 o'clock direction on lithotomy position. Duplicated lumen was checked with a metal catheter; it was about 1.5 cm in length ending blindly without connection to the rectum.

Conclusion: ACD is a rare congenital intestinal anomaly located posterior to the anus. It can be confused with other types of anorectal pathologies, such as hemorrhoids, fistula-in-ano, and perianal abscess at the time of diagnosis. Although ACD is often asymptomatic, it should be removed surgically because of the risk of inflammatory complications and colloidal cancer.