Rethinking Diverticulitis Treatment and Prevention
Current treatment guidelines for diverticulitis, a complication of diverticular disease, usually include antibiotics. An article published recently in Drug, Healthcare and Patient Safety examines the evidence for this treatment and explores other potential options.1
Diverticular disease and diverticulosis are interchangeable terms meaning the presence of diverticula, small sac-like out-pouchings that balloon right through the colon lining to the outer wall. It occurs in only 5% of the Western adult population younger than forty years of age, but it rises sharply to occur in at least 50% of those who are older than fifty and 75% of those older than seventy-nine.
The wide geographic variability of diverticular disease and its striking correlation with a Western diet has long suggested a dietary factor as its root; however, the exact cause of this disease remains unknown. One theory is that diverticula occur when pressure, such as that caused by constipation, builds up inside the colon and makes the intestinal wall balloon out in spots where the wall is weak.
At some point, in about 10-25% of diverticular disease patients, the diverticula become inflamed and infected (diverticulitis). It is easier to diagnose diverticular disease during an incident of diverticulitis because diverticular disease itself often has no noticeable symptoms. Patients who have diverticulitis usually seek medical help because they experience symptoms such as intense abdominal pain, bleeding, bloating, nausea, or fever. In some rare instances, fistulae, bowel obstruction, and lower intestinal hemorrhage occur, or a diverticulum can perforate, causing a localized abscess. Blood tests might reveal the degree of inflammation present and a number of other tests can help with diagnosing.
Fibre and fluid help soften stool, allowing it to move more quickly and easily through the colon, thereby avoiding excessive pressure against the colon wall. Except when a patient is experiencing an episode of diverticulitis (see below), health care providers usually recommend a diet rich in fibre. This study’s author points out that there is some uncertainty as to whether a high-fibre diet prevents the formation of diverticula or just occurrences of diverticulitis. Either way, a balanced, high-fibre diet with adequate fluid has a number of other health benefits. In addition, despite a prevailing myth, there is no evidence that excluding nuts, corn, or seeds from the diet will benefit the course of diverticular disease, so you can safely continue to enjoy these nutritious high-fibre foods.
Most cases of diverticulitis are mild, requiring only outpatient treatment, usually including a temporary low-fibre or clear liquid diet, physical rest, and a 7-10 day course of broad-spectrum antibiotics. In severe cases, a physician might admit a patient to hospital for intravenous feeding so the bowel may rest.
This study’s author cites two recent, randomized studies that suggest, despite standard practice, physicians should consider reserving antibiotic treatment for complicated diverticulitis only. In one of the studies, which involved 272 patients with mild diverticulitis, researchers compared 81 patients who received antibiotic treatment with 191 patients who did not. They found no significant difference in resolution of the inflammation or chance of recurrence.
Mesalamine is a 5-aminosalicylic acid (5-ASA) medication, which physicians prescribe for some cases of ulcerative colitis, a type of inflammatory bowel disease (IBD). Mesalamine has anti-inflammatory and immunomodulatory properties, and researchers recently studied it as a potential treatment for diverticulitis. In two randomized, double-blind, placebo-controlled studies involving more than two hundred patients, researchers found that mesalamine, both alone and in combination with probiotic supplements, helped to control abdominal pain in patients with diverticulitis and, at a low dose of 3mg/day, had a preventative effect.
Probiotics are living microorganisms that can alter the host microflora and exert specific health benefits without increasing the risk of antibiotic resistance. The study authors describe an older study involving 79 patients, which showed that probiotic treatment plus a course of antibiotic treatment with rifaximin resulted in most patients not experiencing a recurrence of diverticulitis during the follow-up period of one year. The recent study mentioned above, showed that treatment with probiotics along with 5-ASA seem to have a preventative effect. While current evidence is not sufficiently substantial to suggest probiotics as a preventative treatment for diverticulitis, it does warrant further research.
In a small, retrospective, open-label trial involving 31 diverticulitis patients, individuals receiving daiobotanpito, a traditional Japanese herbal medicine (Kampo), along with in-hospital intravenous antibiotic treatment, experienced a reduced period of fever, increased relief of abdominal pain, and reduced antibiotic administration compared with the study participants who received antibiotic treatment alone.
Previous research has shown that butyrate, a short-chain fatty acid, seems to provide symptomatic relief for patients suffering from a range of gastrointestinal conditions, including diarrhea and IBD. A recent double-blind, randomized, placebo-controlled study assessed the role of butyrate in preventing recurrences of diverticulitis. Seventy-three patients who had experienced at least one incidence of diverticulitis within the year immediately preceding the study received either 400mg/day of sodium butyrate or placebo. After a year, only two patients in the treatment group had a recurrence of diverticulitis compared to seven in the placebo group. The study author suggests that researchers should further explore preventative treatments that help to reinforce the colonic mucosal barrier, thereby decreasing inflammation and increasing healing of the mucosa.
In the past, practitioners believed that two significant attacks of diverticulitis warranted surgery to remove the diverticula and thereby prevent recurrence of diverticulitis. However, this study’s author says that available research shows that diverticulitis has a natural history that is more benign than previously thought. As a result, newer guidelines do not encourage preventative surgery for diverticulitis. In fact, these guidelines now recommend that physicians make surgery decisions on a case-by-case basis. Currently, only about 1% of diverticular patients require surgery, which involves resection of the affected area. In many cases, the surgeon can remove the damaged portion of the bowel (partial colectomy) and connect the remaining ends together, avoiding the necessity of a colostomy.
Based on recent developments, additional high-quality studies are warranted to assess whether antibiotics are always necessary in the management of uncomplicated diverticulitis. Preliminary research also indicates the potential for a variety of preventive treatments, such as nutritional or probiotic supplements, but additional, high-quality studies are required to prove their effectiveness. In the meantime, the GI Society will continue to track emerging research into this common but troublesome condition.