• **Management of colorectal duplication**

If the baby has efficient bowel movements, is preferably breastfed, is gaining weight, and no other severe associated malformations require surgical intervention, we recommend delaying further treatment until a complete assessment of the types and extension of malformations is done and an individually tailored treatment plan can be made bringing the family together with the multidisciplinary team. The type of malformation determines the surgical strategy at birth: primary repair (not the best choice in these complex patients), temporary anal calibrations to ensure efficient bowel movements until definitive repair or colostomy creation. The purpose of surgical reconstruction is to have a single anal opening located within the complex muscle either by removal of the anal side opening outside of the sphincter [7,8] or joining of the two anorectal ends and positioning in the muscle sphincter [9]. Depending on the duplication length and anatomical variant, if the two duplicated colons are not fused and have a separate blood supply, one side should be removed if not, stripping of the mucosa on the non-dominant side [10] or stapling the common wall [9] (similar with stapling the common wall in Duhamel procedure [11]) to ensure efficient emptying, to avoid complications such as severe constipation [12] with fecal impaction, volvulus, or neoplastic changes. End-to-side anastomosis of the two colonic lumens should not be the first option because of the risk of stenosis at the anastomotic site in the long-term with fecal impaction and proximal colitis [3]. This can also make difficult efficient emptying of both lumens if antegrade continence will be required in patients with low the potential for fecal continence [9].
