Key Clinical Message
Small bowel volvulus is a rare cause of small bowel obstruction, but must be considered as the likely diagnosis when mesenteric ‘whirlpool sign’ is present on imaging. Peritonism with such imaging findings warrants prompt intervention.
A 65 year-old female presented to hospital with 3 days of abdominal pain and distension. She had a background of diverticular disease and previous hysterectomy for symptomatic fibroids. Her white-cell-count was 19.5 x 109/L and lactate 3.1mmol/L. Computed tomogram (CT) of the abdomen/pelvis revealed abnormal, oedematous distal small bowel (Figure 1). The mesentery was congested alongside demonstrating the ‘whirlpool sign’ of small bowel volvulus. Small bowel distal to this loop was collapsed whereas proximally the bowel was dilated and fluid-filled. Closed-loop small bowel obstruction was diagnosed secondary to small bowel volvulus. At laparotomy, there was internal herniation from mesenteric twisting. 100cm of ileum was gangrenous (Figure 2). Resection was performed with stapled side-to-side primary anastomosis. Discharge was at day 10 post-operatively.
Small bowel volvulus is rare in the West, accounting for 1-6% of small bowel obstructions1. It is predominantly associated with post-surgical adhesions, congenital midgut malrotation and fibrinous bands across the mesentery2. Diagnosis is made via CT scan, which will show a ‘whirlpool sign’ with twisting of the small bowel and vessels around its mesentery1. Whirlpool sign on CT scan indicates an odds ratio of 25.3 with regards to operative intervention2. Swift diagnosis and intervention is vital to prevent frank ischaemia.