A 33-year-old gentleman presents with upper abdominal pain and vomiting. Blood tests demonstrate a raised white cell count and an amylase of 300IU/L. Of the following differentials, which is the LEAST likely to be correct?

d. The transverse colon is spared many of the complications that are commonly seen in the sigmoid colon; the site of most pathology in the gastrointestinal tract. A host of conditions including diverticulitis, volvulus, colorectal carcinoma and angiodysplasia to mention but a few afflict this area. Ruptured aortic aneurysms are most often seen in older men, however, the clinical picture of upper abdominal pain, raised inflammatory markers and a high amylase in a clinically unstable patient should prompt investigation to rule out this fatal condition. Pancreatitis is one of the most likely causes of the above clinical picture and an amylase less than the often quoted limit of 4 times normal (360IU/L) does not exclude this common condition.