Methods (differential diagnosis, investigations and treatment)
Laboratory values including white blood cell count, renal function and lactate were within normal limits. CT scan of the abdomen and pelvis showed pneumoperitoneum with a large amount of free air in the upper abdomen, with associated mild ascites (Figure 1). No clear location of ruptured viscus or inflammation was visible. There were also fluid-filled distended loops of small bowel and massive distention of the mid-transverse colon (Figure 2) and right colon (Figure 3) containing air, stool and opaque material.