Diverticulum of colon

Colonic diverticula are pouch-like outpouchings of the colonic wall. They can be single, but more often occur as a series of sac-like protrusions from the lumen outward. Colonic diverticula can be divided into true and acquired types. True diverticula are congenital full-thickness weaknesses of the colonic wall, and the diverticulum contains all layers of the bowel wall. Acquired diverticula are herniations of mucosa through weak points in the muscular layer of the bowel wall; therefore, they are secondary to increased intraluminal pressure forcing the mucosa outward through weak areas of the intestinal musculature. The causes of colonic diverticula include congenital factors, acquired factors, and other related factors. Treatment may include non-surgical management and surgical treatment. Acquired colonic diverticulosis affects a considerable proportion of the population in Western countries, but the true prevalence of this disease is difficult to determine. Radiographic data overestimate the prevalence because the subjects examined are all patients with gastrointestinal symptoms. Conversely, autopsy data underestimate the prevalence because small colonic diverticula are easily missed during postmortem examination. Approximately 5%-10% of people over 45 years of age develop acquired colonic diverticula, while in those over 85 years, up to two-thirds have the disease. In any case, regardless of the true numbers, acquired colonic diverticula increase with age in both autopsy and barium enema X-ray studies. Acquired colonic diverticulosis is more common in females, with a male-to-female ratio of 2:3. The average age at presentation is 61.8 years, with over 92% being over 50 years of age. The sigmoid colon is involved in 96% of patients; in 65.5% of patients, the sigmoid colon is the only site involved. Approximately half of the patients have a symptom duration of less than 1 month before presentation. Patients with more extensive disease have shorter symptom durations than those with more localized disease. Among initially hospitalized patients, 65% receive medical treatment and 35% require surgical treatment. Of those successfully treated medically, 26% require further management. More than 90% of patients present within 5 years of the initial episode. The mortality rate for those with a second episode is twice that of those with a first episode. Moreover, whether treated medically or surgically, persistent or recurrent symptoms are common.