Diverticulitis is an inflammation of an area of the colon where small pouches have formed and subsequently perforated releasing bacteria into the abdomen that causes inflammation and infection. While some diverticula (pouches) are present from birth and remain throughout a patient’s life, most are acquired and probably are related to a western diet (high fat and low fiber). Having the pouches is termed “diverticulosis” and having inflammation of the pouches is termed “diverticulitis”. Once the pouches are present, there is always the possibility that they may perforate and cause pain or possibly abscess (collection of pus) or in severe cases, there may actually be stool that leaks into the abdomen. In addition, the pouches make the colon prone to bleeding and may be the most common cause of colonic bleeding that presents as bleeding per rectum.
The risk of diverticulitis or perforation of the pouches: Up to 25% of individuals who have the pouches may develop diverticulitis in their lifetime. The risk of having a severe or significant bleed from the pouches may be as high as 20% in a patient’s lifetime. This means that most people with diverticulosis will never have a problem despite the fact that the disease is present.
The best way to diagnosis diverticulosis or presence of the pouches is with colonoscopy. In addition, should significant bleeding be present from a diverticula, often times colonoscopy can be used to stop the bleeding and prevent the need for an emergency removal of that segment of colon. The best way to diagnose diverticulitis is with a CAT scan of the abdomen and pelvis which would show the inflammation and whether there is any abscess formation that may need to be drained either surgically or radiologically.
Should a patient present with diverticulitis, the severity of the perforation will dictate the type of treatment that is recommended. For instance, a mild case of diverticulitis would have no significant abscess and could be simply be treated with antibiotics with over 80% of these people resolving the episode without need for surgery. If an abscess is present and it is small (2 cm or less), then this will usually resolve with antibiotics, but larger abscesses may need to be drained by radiology or surgically. Should a significant perforation occur where pus spreads throughout the belly, this will require an emergency operation and removal of that segment of colon. The patient will usually require a temporary bag in this instance. Should stool spread throughout the belly from a very large perforation, this is a surgical emergency that not only will most likely end up with a colostomy but may require multiple operations to prevent severe infection.
Most patients with uncomplicated diverticulitis respond simply with antibiotics either orally as an outpatient or in more significant cases through an I.V. while admitted to the hospital. If a patient has a single episode of diverticulitis, the chance of a second episode of diverticulitis is approximately 20-30% in a patient’s lifetime with about half of that occurring within one year of the first episode. 80% of these patients will still respond to antibiotics to clear up the infection and allow the inflammation to resolve. If a patient has had a second episode of diverticulitis, we usually recommend an elective operative removal of that segment of colon without the need for a bag and this usually can be performed laparoscopically.
Complicated diverticulitis occurs when there is perforation into an adjacent structure such as the bladder or the vagina. This would be evidenced by the passage of air with urination or the passage of air or stool from the vagina. Recurrent urinary tract infections may also be caused from complicated diverticulitis. Should these symptoms occur, the area of the colon that is involved will need to be removed surgically and this sometimes can be performed laparoscopically, although sometimes requires an emergency operation and a temporary bag.
Diverticulitis can also present with bowel obstruction or the inability to pass stool and this may be because of multiple prior episodes that have narrowed the colon to a point where stool cannot move forward into the rectum. Obstruction is another indication for operation, but emergency surgery often needs a temporary bag.
To try to prevent a case of diverticulitis, a high fiber diet as defined as 35 grams of fiber per day will keep the stool soft and less likely to get stuck in the pouches and perforate. A significant amount of water should also be taken on a daily basis to keep the stool soft. Fiber products that are available over the counter as well as stool softeners are good supplements to maintain a soft stool that does not require significant straining to pass.