An unusual cause of abdominal pain.

A 36-year-old man presented with a 7-day history of intermittent right-sided abdominal pain. He also had a reducible right-sided inguinal hernia for the past 10 years. He was initially managed as acute hepatitis as there was right hypochondrial tenderness associated with elevated liver enzymes. Two days later, a mass was palpable in the right iliac fossa. A computed tomography (CT) scan of the abdomen was performed. What does the CT scan show? 1) Appendiceal mass 2) Omental torsion 3) Empyema of the gallbladder 4) Retroperitoneal tumour 5) Ascending colon carcinoma