Diverticular disease: reconsidering conventional wisdom.

Colonic diverticula are common in developed countries and complications of colonic diverticulosis are responsible for a significant burden of disease. Several recent publications have called into question long-held beliefs about diverticular disease. Contrary to conventional wisdom, studies have not shown that a high-fiber diet protects against asymptomatic diverticulosis. The risk of developing diverticulitis among individuals with diverticulosis is lower than the 10% to 25% proportion that commonly is quoted, and may be as low as 1% over 11 years. Nuts and seeds do not increase the risk of diverticulitis or diverticular bleeding. It is unclear whether diverticulosis, absent diverticulitis, or overt colitis is responsible for chronic gastrointestinal symptoms or worse quality of life. The role of antibiotics in acute diverticulitis has been challenged by a large randomized trial that showed no benefit in selected patients. The decision to perform elective surgery should be made on a case-by-case basis and not routinely after a second episode of diverticulitis, when there has been a complication, or in young people. A colonoscopy should be performed to exclude colon cancer after an attack of acute diverticulitis but may not alter outcomes among individuals who have had a colonoscopy before the attack. Given these surprising findings, it is time to reconsider conventional wisdom about diverticular disease.