Giant Diverticulum of the Colon: A Possible Pathogenesis

Abstract

Giant diverticula of the colon are a rare complication of acquired diverticular disease, but 5 cases have been presented in Norwich within recent years. Patients may present with lower abdominal pain and be found to have a firm, round, resonant mass, usually on the left side of the abdomen. Plain abdominal x-ray shows an air-filled cavity with a smooth outline. Barium enema examination reveals diverticular disease and, in 60% of subjects, a communication between the colon and the diverticulum. We suggest that this complication of diverticular disease of the colon occurs rarely because of the requirement for the diverticulum to be surrounded by a fatty mantle, either an appendix epiploica or retroperitoneal fat. Inflammation of the diverticulum is thus contained, allowing for progressive distension by a gas-trapping mechanism. Once diagnosed, the lesion should be excised to prevent complications.