This supplementary information is presented as submitted by the corresponding author. It has not been copy-edited by NTvG.
A malrotation is a congenital birth defect caused by an abnormal intestinal rotation during fetal development. Almost half of all malrotations stay undiagnosed until adolescence or later. Presenting symptoms in adulthood can be non-specific and can easily lead to misdiagnosis. We describe a 20-year-old female patient with chronic abdominal pain and a disordered eating pattern that were interpreted as being psychosomatic despite extensive somatic evaluations. The diagnosis malrotation was only made after finding extensive intestinal necrosis during an emergency laparotomy, resulting in right sided hemicolectomy.
Patient A, a 20-year-old female, presented at the Emergency room with acute abdominal pain, nausea and vomiting. Her medical history mentioned an Other Specified Feeding or Eating Disorder (OSFED), Irritable Bowel Disease (IBD) and lactose-intolerance. On physical examination she appeared hemodynamically stable, although cachectic with a BMI of 12kg/m2. Her abdomen showed right sided tenderness with no signs of peritonitis. Laboratory results and abdominal ultrasound (after the pain had already dissipated) were normal. In the past patient A had presented multiple times at different hospitals with similar symptoms. Despite extensive evaluation a physical explanation was never found. Nevertheless, she was admitted to the hospital for observation. On the second day, patient A again reported abdominal pain, but this time she also had bloody diarrhea and tachycardia. Her abdomen was distended, tender, and peristalsis was absent. Abdominal CT showed dilation and reduced enhancement of the ascending and proximal transverse colon. During an emergency laparotomy, necrosis of the ascending and transverse colon were found, caused by a volvulus. The caecum was located in the upper right quadrant and the proximal transverse colon was located in the upper left quadrant. The volvulus resulted from a very mobile colon with narrow mesentery base, indicating a congenital malrotation. The postoperative course was complicated by a perforation of the terminal ileum for which additional resection was performed. The patient is currently still recovering.
Missing the diagnosis in this case may not only be explained by the nonspecific symptoms that a congenital malrotation presents with. In addition, cognitive strategies used by doctors to make diagnoses may have led to ignoring details that did not fit earlier diagnoses. Eating disorders and gastrointestinal disease, however, are sometimes difficult to distinguish and are often linked. Even with extra vigilance a misdiagnosis cannot always be avoided.