Meta-analysis: long-term therapy with rifaximin in the management of uncomplicated diverticular disease

One year intermittent rifaximin plus fibre supplementation vs. fibre supplementation alone to prevent diverticulitis recurrence: a proof-of-concept study

BACKGROUND

Evidence supporting appropriate medical therapy to prevent recurrence of colonic diverticulitis is limited. Our goal was to evaluate the potential of rifaximin given periodically in addition to fibre for the prophylaxis of recurrences.

METHODS

We conducted a multicentre, randomized, open controlled study in patients with a recent episode of colonic diverticulitis, currently in remission. Patients received 3.5 g of high-fibre supplementation b.d. with or without one week per month of the non-absorbable antibiotic rifaximin (400 mg b.d.) for 12months. Primary endpoint was recurrence of diverticulitis, encompassing acute symptomatic flare with or without complications, analyzed by multivariable logistic regression analysis and by Cox proportional hazard method.

RESULTS

After randomizing 165 patients, the study was interrupted since the recruitment rate was largely below the minimum anticipated, and the trial was switched from evidence-gathering to proof-of-concept. Recurrences occurred in 10.4% of patients given rifaximin plus fibres vs. 19.3% of patients receiving fibres alone. The logistic analysis adjusted for sex, age, illness duration, time from last episode, disease localization and centre recruitment rate, yielded a significant treatment effect (odds ratio 3.20; 95% confidence interval: 1.16-8.82; P=0.025). Patients with diverticulitis diagnosed since ≥1 year receiving rifaximin also had a lower incidence of recurrences (10%; 95% confidence interval: 2-47% vs. 67%; 95% confidence interval: 37-100%). Both treatments were safe.

CONCLUSIONS

This study represents a proof-of concept of the efficacy of cyclic rifaximin treatment, added to fibre supplements, to reduce the risk of recurrences of diverticulitis in patients in remission.

High-fibre diet and Lactobacillus paracasei B21060 in symptomatic uncomplicated diverticular disease

AIM: To investigate in symptomatic uncomplicated diverticular disease the efficacy of symbiotics associated with a high-fibre diet on abdominal symptoms.

METHODS: This study was a multicentre, 6-mo randomized, controlled, parallel-group intervention with a preceding 4-wk washout period. Consecutive outpatients with symptomatic uncomplicated diverticular disease, aged 40-80 years, evaluated in 4 Gastroenterology Units, were enrolled. Symptomatic uncomplicated diverticular disease patients were randomized to two treatment arms A or B. Treatment A (n = 24 patients) received 1 symbiotic sachet Flortec^© (Lactobacillus paracasei B21060) once daily plus high-fibre diet for 6 mo. Treatment B (n = 21 patients) received high-fibre diet alone for 6 mo. The primary endpoint was regression of abdominal symptoms and change of symptom severity after 3 and 6 mo of treatment.

RESULTS: In group A, the proportion of patients with abdominal pain < 24 h decreased from 100% at baseline to 35% and 25% after 3 and 6 mo, respectively (P < 0.001). In group B the proportion of patients with this symptom decreased from 90.5% at baseline to 61.9% and 38.1% after 3 and 6 mo, respectively (P = 0.001). Symptom improvement became statistically significant at 3 and 6 mo in group A and B, respectively.

The proportion of patients with abdominal pain >24 h decreased from 60% to 20% then 5% after 3 and 6 mo, respectively in group A (P < 0.001) and from 33.3% to 9.5% at both 3 and 6 mo in group B (P = 0.03). In group A the proportion of patients with abdominal bloating significantly decreased from 95% to 60% after 3 mo, and remained stable (65%) at 6-mo follow-up (P = 0.005) while in group B, no significant changes in abdominal bloating was observed (P = 0.11). After 6 mo of treatment, the mean visual analogic scale (VAS) values of both short-lasting abdominal pain (VAS, mean ± SD, group A: 4.6 ± 2.1 vs 2.2 ± 0.8, P = 0.02; group B: 4.6 ± 2.9 vs 2.0 ± 1.9, P = 0.03) and abdominal bloating (VAS, mean ± SD, group A: 5.3 ± 2.2 vs 3.0 ± 1.7, P = 0.005; group B: 5.3 ± 3.2 vs 2.3 ± 1.9, P = 0.006) decreased in both groups, whilst the VAS values of prolonged abdominal pain decreased in the Flortec^© group, but remained unchanged in the high-fibre diet group (VAS, mean ± SD, group A: 6.5 ± 1.5 vs 4.5 ± 2.1, P = 0.052; group B: 4.5 ± 3.8 vs 5.5 ± 3.5).

CONCLUSION: A high-fibre diet is effective in relieving abdominal symptoms in symptomatic uncomplicated diverticular disease. This treatment may be implemented by combining the high-fibre diet with Flortec^©.

Diverticular disease as a chronic illness: evolving epidemiologic and clinical insights

Diverticular disease imposes a significant burden on Western and industrialized societies. The traditional pathogenesis model posits that low dietary fiber predisposes to diverticulosis, and fecalith obstruction prompts acute diverticulitis that is managed with broad-spectrum antibiotics or surgery. However, a growing body of knowledge is shifting the paradigm of diverticular disease from an acute surgical illness to a chronic bowel disorder composed of recurrent abdominal symptoms and considerable psychosocial impact. New research implicates a role for low-grade inflammation, sensory-motor nerve damage, and dysbiosis in a clinical picture that mimics irritable bowel syndrome (IBS) and even inflammatory bowel disease (IBD). Far from being an isolated event, acute diverticulitis may be the catalyst for chronic symptoms including abdominal pain, cramping, bloating, diarrhea, constipation, and "post-diverticulitis IBS." In addition, studies reveal lower health-related quality of life in patients with chronic diverticular disease vs. controls. Health-care providers should maintain a high index of suspicion for the multifaceted presentations of diverticular disease, and remain aware that it might contribute to long-term emotional distress beyond traditional diverticulitis attacks. These developments are prompting a shift in therapeutic approaches from widespread antimicrobials and supportive care to the use of probiotics, mesalamine, and gut-directed antibiotics. This review addresses the emerging literature regarding epidemiology, pathophysiology, and management of chronic, symptomatic diverticular disease, and provides current answers to common clinical questions.

[Colonic diverticular disease: diagnosis and therapy]

Colonic diverticular disease is one of the most common gastrointestinal disorders in the Western world, affecting approximately 50% of the population above the age of 70 years. Symptoms develop only in about one quarter of the affected individuals with complications in one-third of the symptomatic patients. Diagnosis is mostly confirmed by colonoscopy. Abdominal CT is the most sensitive for the diagnosis of complicated severe diverticulitis, while colonoscopy or in severe cases angiography may be performed in bleeding patients. Initial therapy of non-complicated symptomatic diverticulitis includes antibiotics and more recently non-absorbable antibiotics. In complicated cases should be treated with broad spectrum i.v. antibiotics, however surgery may became necessary in a minority of the cases. The proportion of patients needing acute surgical intervention has decreased in the last decades with the advancement of conservative management including medical therapy, endoscopy and imaging techniques and the indication of elective was also changed.

Management of colonic diverticular disease with poorly absorbed antibiotics and other therapies

Colonic diverticular disease is common in Western countries and its prevalence increases with age. The large majority of patients (80-85%) will remain entirely asymptomatic throughout their life. In symptomatic cases, most patients will have diverticulosis without inflammation while the remainder will have diverticulitis with or without complications. About 1-2% will require hospitalization and 0.5% will require surgery. Factors predicting the development of symptoms remain to be identified. However, it is generally recognized that diverticular disease is probably related to complex interactions between colon structure, intestinal motility, diet, and genetic features. Epidemiologic studies have demonstrated an association between diverticulosis and diets that are low in fiber and high in refined carbohydrates. Although the causes of symptom development are still unclear, it is thought that previous episodes of intestinal inflammation may play a role. Changes in intestinal microflora could be one of the putative mechanisms responsible for low-grade inflammation. In patients with uncomplicated diverticulosis, a diet abundant in fruit and vegetables is recommended. The current therapeutic approaches in preventing recurrence of symptoms are based on nonabsorbable antibiotics, mesalazine, and/or probiotics. Cyclic rifaximin administration seems to be an adequate approach to relieving symptoms and preventing acute diverticulitis in patients with symptomatic diverticulosis.