another major surgery, during which the surgeon rejoins the colon and rectum and reverses the colostomy. Epidemiology Diverticulitis most often affects the elderly. In Western countries, diverticular disease most commonly involves the sigmoid colon (95 percent of people with diverticulitis). Diverticulosis affects 5% to 45% of individuals with the prevalence of diverticulosis increasing with age from under 20% of individuals affected at age 40 up to 60% of individuals affected by age 60. Left-sided diverticular disease (involving the sigmoid colon) is most common in the West, while right-sided diverticular disease (involving the ascending colon) is more common in Asia and Africa. Among people with diverticulosis, 4 to 15% may go on to develop diverticulitis. References External links Diverticulosis and diverticulitis at NIDDK Diverticulitis at Mayo Clinic Staging of Acute Diverticulitis archive of link above Diseases of intestines Wikipedia medicine articles ready to translate Wikipedia emergency medicine articles ready to translate