Diverticulosis is the condition of having multiple pouches (diverticula) in the colon that are not inflamed. These are outpockets of the colonic mucosa and submucosa through weaknesses of muscle layers in the colon wall. They typically cause no symptoms. Diverticular disease occurs when diverticula become inflamed, known as diverticulitis, or bleed.
It is common in Western countries with about half of those over the age of 60 in Canada and the United States affected. Diverticula are uncommon before the age of 40, and increase in incidence beyond that age. Rates are lower in Africa which has been attributed to a shorter life expectancy and poor healthcare access. However, earlier epidemiological studies by Burkitt suggested that the lower incidence of diverticulosis coli in Africa correlated with softer stools in native populations who consume a high-roughage diet in contrast with the refined, lower-roughage diet of Western populations.
Many health-conscious men can recite their cholesterol counts, blood pressure readings, and PSA levels without even glancing at their medical records. But few of these well-informed gents can tell you if they have diverticular disease of the colon, even though it’s an extremely common condition. That’s understandable, since the most prevalent form of the problem, diverticulosis, produces few if any symptoms. Still, when complications develop, blissful ignorance about diverticulosis abruptly gives way to an unwelcome education about the pain of diverticulitis or the bleeding of diverticulosis. It’s a learning experience that’s particularly unfortunate, since diverticular disease is largely preventable.
Symptoms of Diverticulitis
Diverticulitis, infection and inflammation of diverticula, can occur suddenly and without warning.
Symptoms of diverticulitis may include:
- Alternating diarrhea and constipation.
- Painful cramps or tenderness in the lower abdomen.
- Chills or fever.
How Is Diverticulosis Diagnosed?
Because people with diverticulosis do not have any symptoms, it is usually found through tests ordered for an unrelated reason.
How Is Diverticulitis Diagnosed?
If you are experiencing the symptoms of diverticulitis, it is important to see your doctor.
Your doctor will ask questions about your medical history (such as bowel habits, symptoms, diet, and current medications) and perform a physical exam, possibly including a digital rectal exam.
One or more diagnostic tests may be ordered. Tests may include X-rays, CT scanning, ultrasound testing, a sigmoidoscopy, colonoscopy, and blood tests to look for signs of infection or the extent of bleeding.
In people with rapid, heavy rectal bleeding, the doctor may perform a procedure called angiography to locate the source of the bleeding.
Diverticulitis is one main complication of diverticular disease of the colon. The other is diverticular bleeding. It occurs when a diverticulum erodes into the penetrating artery at its base (see Figure 2). Because acute inflammation is absent, patients with diverticular bleeding don’t have pain or fever.
The most common symptom is painless rectal bleeding. Since diverticular bleeding occurs in the colon, it produces bright red or maroon bowel movements. (In contrast, when bleeding occurs in the stomach, the blood is partially digested as it passes through the intestinal tract, so it appears as black, tar-like bowel movements).
In most patients, the bleeding is mild, and it usually stops on its own with bowel rest. But brisk bleeding is a life-threatening emergency. It requires expert hospital care with blood transfusions and IV fluids. It also requires aggressive attempts to locate the site of bleeding and to stop it. Several techniques are available; most experts recommend colonoscopy (doctors can see the bleeding artery through the scope and cauterize or clip it to stop the bleeding) or angiography (doctors thread a catheter into the artery that supplies blood to the colon, inject dye to see the bleeding artery on x-rays, and then inject medication to constrict the artery and stop the bleeding). If neither approach stops the bleeding, surgery may be needed.
How Is Diverticulosis Treated?
Since bacteria are responsible for the inflammation, antibiotics are the cornerstone of treatment. And because the colon harbors so many bacterial species, doctors must prescribe treatment that will target a broad range of bacteria, including Bacteroides and other anaerobic bacteria that grow best without oxygen, as well as E. coli and other aerobic (oxygen-requiring) microbes. A common approach is to prescribe metronidazole (Flagyl, generic) for the anaerobes along with ciprofloxacin (Cipro, generic) or trimethoprim-sulfamethoxazole (Bactrim, generic) for the aerobes. Amoxicillin–clavulanic acid (Augmentin) is effective against both types of bacteria and is a good alternative. Needless to say, there are many variations on the theme, and doctors must always take their patients’ allergies and general health into consideration when they prescribe antibiotics.
Patients with mild-to-moderate diverticulitis can take their antibiotics in pill form at home, but patients with severe inflammation or complications (see below) should receive intravenous (IV) antibiotics in the hospital, and then finish up with pills at home. In most cases, seven to 10 days of antibiotics will do the trick.
Bowel rest is also important for acute diverticulitis. For home treatment, that means sticking to a diet of clear liquids for a few days, then gradually adding soft solids and moving to a more normal diet over a week or two. Intravenous fluids can sustain hospitalized patients until they are well enough to switch to clear liquids en route to a full diet.
Because diverticulitis tends to recur, prevention is always part of the treatment plan. And for men with any form of colonic diverticular disease, that means a high-fiber diet.
What are other treatments for diverticulitis?
Liquid or low fiber foods are advised during acute attacks of diverticulitis. This is done to reduce the amount of material that passes through the colon, which at least theoretically, may aggravate the diverticulitis. In severe diverticulitis with high fever and pain, patients are hospitalized and given intravenous antibiotics. Surgery is needed for patients with persistent bowel obstruction, bleeding, or abscess not responding to antibiotics.
What is the surgical treatment for diverticulitis?
Diverticulitis that does not respond to medical treatment requires surgical intervention. Surgery usually involves drainage of any collections of pus and resection (surgical removal) of the segment of the colon containing the diverticula, usually the sigmoid colon. Surgical removal of the bleeding diverticulum also is necessary for those with persistent bleeding. In patients needing surgery to stop persistent bleeding, it is important to determine exactly where the bleeding is coming from in order to guide the surgeon.
Sometimes, diverticula can erode into the adjacent urinary bladder, causing severe recurrent urine infection and passage of gas during urination. This situation also requires surgery.
Sometimes, surgery may be suggested for patients with frequent, recurrent attacks of diverticulitis leading to multiple courses of antibiotics, hospitalizations, and days lost from work. During surgery, the goal is to remove all, or almost all, of the colon containing diverticula in order to prevent future episodes of diverticulitis. There are few long-term consequences of resection of the sigmoid colon for diverticulitis, and the surgery often can be done laparoscopically, which limits post-operative pain and time for recovery.
Diverticular disease of the colon is preventable. A high-fiber diet will sharply reduce the risk of developing diverticula — and even after the pouches form, dietary fiber will reduce the risk of diverticulitis and diverticular bleeding.
The Institute of Medicine recommends 38 grams of fiber a day for men age 50 and under and 30 grams a day for older men (for women, the recommended amount is 30 grams a day for those age 50 and under and 21 grams a day thereafter). Most Americans get much, much less. The table lists the fiber content of some foods and supplements.
Fiber is important for bowel function and general health, but it can be hard to get used to. Many people feel bloated and gassy when they start a high-fiber diet, but if they stick with it, these side effects usually diminish within a month or so. Still, it’s best to ease into a high-fiber diet. Increase your daily intake by about 5 grams per week until you reach your goal, and be sure to have plenty of fluids as well. For most people, a high-fiber cereal is the place to start, but if breakfast isn’t your thing, you can have it any time during the day.
Until recently, doctors banned nuts, seeds, corn, and popcorn from the diet of diverticulosis patients. Although they had no real evidence that these foods were harmful, doctors worried that these small particles might pass into the colon undigested and then lodge in the mouth of a diverticulum, blocking the pouch and making things worse. But a 2008 Harvard study put these fears to rest. During the 18-year study, the men who ate the most nuts and popcorn actually had a lower risk of acute diverticulitis than the men who ate the least; there was no change in the risk of bleeding, for better or worse.
Scientists are experimenting with other ways to prevent attacks of diverticulitis and episodes of bleeding; among other things, long-term nonabsorbable oral antibiotics are under study. Men with diverticular disease might be wise to avoid or minimize their use of nonsteroidal anti-inflammatory drugs, which may (or may not) increase the risk of trouble. Even so, dietary fiber remains the key to preventing diverticulitis and its complications. And if that’s not enough reasons to chow down lots of “roughage,” consider the other benefits of a high-fiber diet.
Dietary fiber fights constipation. Because it reduces straining that puts pressure on the abdomen and the veins, fiber reduces the risk of hernias, hemorrhoids, and even varicose veins. In some, but not all, studies, fiber has been linked to a reduced risk of colon cancer. Fiber is filling, and it helps combat obesity. It improves blood sugar metabolism, lowering the chances of developing diabetes. It lowers blood pressure. Some forms of fiber (soluble fiber) reduce blood cholesterol levels, and according to a Harvard study of 43,757 men, a high-fiber diet appears to reduce the risk of heart attacks by 41%.