Anorectal malformation, associated with colon atresia and intestinal malrotation, a case report

In this case report from Muhimbili National Hospital, Dar es salaam, Tanzania, we present the unexpected findings of anorectal malformation, colonic atresia, and intestinal malrotation in a 2-day old neonate. This combination is exceedingly rare, with only case reports published in the literature. We describe the challenges in diagnosis and offer our insights based on this experience and review of the literature.

Our patient was a male born at term, weighing 2600 g, diagnosed clinically with a high anorectal malformation. He was planned for colostomy, and we unexpectedly found a collapsed descending colon. Exploration revealed intestinal malrotation and three segments of type I colonic atresia from the mid transverse colon to the sigmoid colon in addition to the high anorectal malformation.

Creating a colostomy in a high anorectal malformation and failure to identify proximal intestinal atresia would result in potentially devastating consequences. Colonic atresia and anorectal malformation will both present as large bowel obstruction. In the extremely rare situation, when occurring in combination, the obvious clinical diagnosis of anorectal malformation will mask the clinical suspicion of the possibility of colonic atresia. Finding a distal bowel air bubble above the pubococcygeal line on an invertogram is useful in identifying proximal atresia preoperatively.

The current report emphasizes the importance of maintaining an awareness of possible associated colonic atresia in neonates with anorectal malformation. An invertogram and intraoperative finding of a collapsed descending colon should prompt evaluation for a proximal obstructing lesion.