Malrotation of the bowel is the commonest non-syndromic anomaly associated with OA/TOF. During normal foetal development (week 6 gestation), the bowel herniates into the umbilical cord then returns back into the body, rotating as it does so. In malrotation, this goes wrong in a number of possible ways, resulting in the bowel being wrongly positioned and/or fixed incorrectly. This can cause severe twisting, causing disruption to blood flow to the bowel, volvulus and death of a large part of bowel. (52, 64–66)
Prevalence of malrotation in the presence of OA/TOF varies in different studies between 3% and 5% (71–73). This compares to a population prevalence of 1 in 500. Most present at less than 1 month old with vomiting, but can present later, including adulthood. In this instance, it can be with non-specific symptoms like diarrhoea, abdominal colic, recurrent vomiting, but also volvulus and intestinal herniation is possible. (74)
This can vary from vague symptoms post eating to an acute abdomen. These milder symptoms may have persisted for many years undiagnosed: (75)
This can present as an acute surgical emergency such as:
This is surgical – Ladd’s procedure which reduces volvulus, removal of Ladd’s bands, and widening of the mesenteric base to prevent the bowel twisting again.
Assessment of nutritional status and treatment of any deficiencies.