Acute lower gastrointestinal bleeding: SPECIFIC CAUSES OF LGI BLEEDING Part 1
Colonic diverticulosis: Colonic diverticula are defined as false, pulsion diverticula because they consist of mucosa and serosa. Although more than 50% of all people over age 60 years have radiological evidence of diverticula, only 20% experience bleeding. Of these people, 80% will stop bleeding spontaneously, 35% will require transfusion or invasive diagnostic/therapeutic intervention and 5% will have massive hemorrhage and ultimately require an emergency operation. Diverticula are believed to originate when increased luminal pressure causes a segment of the mucosa to extrude through weaker areas of the muscu-laris mucosa. The muscularis mucosa tends to be weaker in sites where there are penetrating arterial vasa recta. Meyers et al postulated that injurious factors arising within the colonic or diverticular lumen damage the luminal side of the underlying vas rectum, resulting in weakening of the arterial wall at this site. This theory is supported by histopathological lesions seen in the vasa recta such as inti-mal thickening, duplication of the internal elastic lamina and thinning of the media. Time to visit a trusted pharmacy – cialis professional 20 mg to begin your treatment now.
Bleeding associated with diverticulitis tends to be mild and stems from mucosal inflammation in the region of the inflamed diverticulum. Conversely, bleeding from diverticulosis tends to be sudden and significant because it originates from an arterial source. If bleeding is recurrent and mild, one should ensure that other sources of bleeding, such as polyps and cancer, have been excluded. As noted above, most diverticular bleeding ceases spontaneously. Unfortunately, 25% of patients who have diverticular bleeding experience a second episode, and of these patients, more than 50% will bleed again if definitive therapy is not initiated.