OBSTRUCTIVE COLITIS - ANALYSIS OF 7 PATIE NTS

The term ''obstructive colitis'' is defined by the presence of ulcero- inflammatory lesions in a colonic area proximal to a potentially obstr uctive lesion. Seven cases retrospectively identified during a 5-year period are here reported. They illustrate the clinico-pathological spe ctrum of this entity. Most patients were women, with a mean age of 66 years and with history of chronic underlying disease (diabetes mellitu s and arterial hypertension). Abdominal distension and pain, as well a s acute constipation were the main clinical symptoms. An adenocarcinom a predominantly located at the rectosigmoidal region accounted for the obstructive nature in 100% of cases. Macroscopically the colitis area was moderately dilated and there were single or confluent ulcers in t he luminal surface. Characteristically, there was always a transitiona l preserved area between the obstruction and the colitis area. Microsc opically, the mucosa was totally replaced by a granulation tissue with a relevant inflammatory infiltrate involving up to the muscularis pro pria, The cytometric study revealed and increase in the cell cycle (S- phase) and proliferation index, at the level of the obstructive lesion , with marked aneuploidy in cases with advanced neoplastic invasion. T he role of mural hypoperfusion with localized ischemia in the pathogen esis is discussed. The similarities with other colonic inflammatory di seases are emphasized.