“Well, I’m still feeling fine,” said the 70-year-old retired college professor as he strode into the office of Marvin M. Lipman, Consumers Union’s chief medical adviser, recently for a routine exam.

Five years earlier he had been hospitalized for acute diverticulitis — his second attack in a year. The two episodes had made his a candidate for elective bowel surgery.

But several small, preliminary studies had just come out reporting good results from the off-label use of two medications to prevent the recurrence of diverticulitis: rifaximin (Xifaxan), an antibiotic approved for traveler’s diarrhea, and mesalamine (Asacol, Pentasa), an anti-inflammatory medication taken for ulcerative colitis. After weighing the pros and cons of putting him on such a treatment, Lipman decided that, although there was no conclusive evidence it would work, his patient had nothing to lose.

Popcorn is not to blame

Diverticulosis is the occurrence of small pockets, or tics, in the wall of the bowel, primarily the sigmoid colon just above the rectum. The condition is uncommon in less industrialized countries, where diets feature lots of high-fiber grains, fruits and vegetables. In the industrialized world, with its low-fiber diet, diverticular disease is an acquired condition. It is rarely found in people under 40 and the incidence increases with age, so that two of every three octogenarians have it.

Most would never know about it but for a routine colonoscopy or a CT scan of the abdomen done for some other reason. But an unlucky minority, some 10 to 20 percent of those with diverticuli (the retired professor among them), at some point become ill with acute signs of infection and inflammation, a condition known as diverticulitis. Common symptoms include left lower abdominal pain and tenderness, an elevated white blood cell count, and fever.

What causes a tic to become a sick tic remains unknown. At one time patients were instructed to avoid nuts, seeds and popcorn, in the belief that those foods became entrapped in the pouches and initiated the infection. Further research has discredited this advice. Recent observations have suggested that chronic inflammation might be present in the wall of the involved section of the bowel even between acute episodes. A flare-up possibly starts when a microperforation through the wall of the tic sets up a focus of infection that spreads to the adjacent bowel.

Whatever the cause, once diverticulitis hits, the standard treatment is a combination of antibiotics, including a fluoroquinolone (ciprofloxacin or levofloxacin) and metronidazole (Flagyl and its generic cousins), and a liquid diet. Often a patient who has had an attack can diagnose another one early and start on a low-fiber liquid diet even before calling a doctor.

Untreated, diverticulitis can result in bowel perforation, with leakage of intestinal contents into the abdomen, abscess formation, severe bleeding or intestinal blockage. Luckily, those complications are uncommon.

To cut or not to cut

Repeated attacks of acute diverticulitis can permanently impair bowel function from scarring, the loss of normal contractions and a narrowing of the affected portion. To prevent this, the standard recommendation has been to operate to remove the diseased portion of the bowel after the second or third attack.

Not surprisingly, few people relish the prospect of such major surgery. That’s why there is a lot of interest in preventive drug treatments such as the one our professor got.

Working on the premise that the inflammatory changes in diverticular disease are similar to those in colitis, investigators began using mesalamine to prevent recurrences of diverticulitis. While effective by itself, some studies have found it to be even more helpful when combined with an antibiotic, and more effective still when a probiotic is added to the mix. While the results are promising, larger and longer studies are needed to assess the validity of those observations.

Copyright 2011. Consumers Union
of United States Inc.