Are fibre supplements really necessary in diverticular disease of the colon? A controlled clinical trial

Can diet change the natural history of gastrointestinal diseases?

Belatedly, gastroenterologists have begun to pay attention to the role of diet in the exacerbation of gastrointestinal symptoms in many digestive disorders-a recognition that has spurred both high-quality clinical trials and translational research into this area. It has become clear that multiple mechanisms acting either in isolation or together can induce gut symptoms and that appropriate interventions can lead to significant relief. What this review will explore is not the role of diet in the production of certain symptoms or symptom clusters, but rather whether a dietary intervention can beneficially alter the natural history of a gastrointestinal disease-a much more demanding expectation. Yet there are examples of where a diet, if sustained, can have a long-term impact on at least some of those affected by conditions such as eosinophilic esophagitis, celiac disease, food allergy, and constipation.

Dietary fibre in gastrointestinal health and disease

Epidemiological studies have consistently demonstrated the benefits of dietary fibre on gastrointestinal health through consumption of unrefined whole foods, such as wholegrains, legumes, vegetables and fruits. Mechanistic studies and clinical trials on isolated and extracted fibres have demonstrated promising regulatory effects on the gut (for example, digestion and absorption, transit time, stool formation) and microbial effects (changes in gut microbiota composition and fermentation metabolites) that have important implications for gastrointestinal disorders. In this Review, we detail the major physicochemical properties and functional characteristics of dietary fibres, the importance of dietary fibres and current evidence for their use in the management of gastrointestinal disorders. It is now well-established that the physicochemical properties of different dietary fibres (such as solubility, viscosity and fermentability) vary greatly depending on their origin and processing and are important determinants of their functional characteristics and clinical utility. Although progress in understanding these relationships has uncovered potential therapeutic opportunities for dietary fibres, many clinical questions remain unanswered such as clarity on the optimal dose, type and source of fibre required in both the management of clinical symptoms and the prevention of gastrointestinal disorders. The use of novel fibres and/or the co-administration of fibres is an additional therapeutic approach yet to be extensively investigated.

Laxative effects of wheat bran and psyllium: Resolving enduring misconceptions about fiber in treatment guidelines for chronic idiopathic constipation

BACKGROUND

Treatment guidelines for chronic idiopathic constipation (CIC) recommend an "increase in fiber intake" as a first-line therapy, but most epidemiologic studies fail to support an association between a high-fiber diet and a reduced risk of constipation. Furthermore, randomized controlled clinical studies show that most isolated fibers (e.g., supplements) are not different from placebo for a laxative effect, and several may be constipating.

OBJECTIVES

The objective of this review was to compare the effects of two isolated fibers, coarse wheat bran and psyllium, on stool output and stool water content in patients with CIC. This review will also address misconceptions about fiber that are perpetuated by treatment guidelines.

DATA SOURCES

A comprehensive literature review was conducted with the use of the Scopus, SciFinder, and PubMed scientific databases, limited to the previous 50 years (1968-2018; latest date included, December 31, 2018).

CONCLUSIONS

In patients with CIC, nonfermented gel-forming psyllium was 3.4 times more effective than insoluble wheat bran for increasing stool output. Both psyllium and coarse wheat bran increased stool water content, a stool-softening effect, but finely ground wheat bran decreased stool water content, a stool-hardening effect.

IMPLICATIONS FOR PRACTICE

It is a misconception that dietary fiber and all isolated fibers provide a laxative effect in patients with CIC. Our analysis suggests that treatment guidelines for CIC should make specific evidence-based recommendations as it pertains to fiber. To do otherwise takes the risk of perpetuating myth and misunderstanding and depriving patients of an effective therapy for CIC. A generic recommendation to "increase fiber intake" is akin to a recommendation to "increase pill intake" without regard to therapeutic or adverse effects.

Prolonged Recurrent Abdominal Pain is Associated With Ongoing Underlying Mucosal Inflammation in Patients who had an Episode of Acute Complicated Diverticulitis

BACKGROUND

Recent data suggest continuous chronic inflammation in patients after an acute diverticulitis (AD) episode.

GOALS

The aim of this article was to compare clinical parameters, inflammatory cytokine expression, and immune-cell infiltrates between patients after severe versus nonsevere AD, as defined by radiology examination during the acute episode.

STUDY

Sixteen patients, after suffering an episode of AD, were included, and, of them, 8 had severe disease. Demographic data, disease characteristics, and inflammatory markers were collected. Tissue samples from diverticular and unaffected tissue were obtained during colonoscopy. Mucosal inflammation was assessed histologically and by measuring inflammatory cytokine mRNA expression.

RESULTS

Clinically, continued nonspecific abdominal symptoms were significantly more prevalent among patients after severe AD compared with patients after nonsevere AD (P=0.0002). Patients after severe AD also had significantly higher C reactive protein levels (9.85±7.5 vs. 3±2.1 mg/dL; P=0.027) and tendency for higher calprotectin levels (115.7±85 vs. 35±8.7 mg/g; P=0.08). Reverse transcription polymerase chain reaction-determined cytokines levels were 5.4±4.4, 5.14±10, and 0.8±0.82 for tumor necrosis factor alpha, interleukin-6, and interleukin-1β, respectively, in affected mucosa compared with 1.06±1.57, 1.56±2.1, and 0.35±0.5, respectively, in nonaffected mucosa (P=0.01, 0.05, 0.14, respectively). Cytokine expression in patients after nonsevere AD did not differ significantly between affected and nonaffected mucosa. Histologic scores for crypt distortion, lymphoid aggregates, and lymphocyte infiltration were all significantly higher in patients after severe AD compared with patients after nonsevere AD (P<0.05 for all comparisons).

CONCLUSIONS

Patients after severe AD have more prolonged chronic symptoms, higher inflammatory markers, higher tissue inflammatory cytokine levels, and more inflammatory infiltrates in diverticular colonic tissue than patients after nonsevere AD. These results may contribute to patients' risk stratification and guide therapeutic decisions.

Effects of Burdock tea on recurrence of colonic diverticulitis and diverticular bleeding: An open-labelled randomized clinical trial

Colonic diverticular bleeding (CDB) and acute colonic diverticulitis (ACD) show high recurrence rates. The establishment of optimal strategies that prevent the recurrence of CDB and ACD is a major concern among gastroenterologists. This study aimed to assess the efficacy of burdock tea for preventing CDB and ACD recurrences. Newly diagnosed patients with CDB (n = 91) or ACD (n = 70) were randomly assigned into two groups. The experimental group received 1.5 g of burdock tea three times a day, whereas the control group did not receive any treatment. The median (interquartile range) of observation for recurrence of CDB or ACD was 22.0 (14.1) months and 30.3 (18.6), respectively. The burdock tea treatment showed significant preventive effects on recurrence of ACD. A lower ACD recurrence rate (5/47 [10.6%] vs. 14/44 [31.8%]) and longer recurrence-free duration was observed in the burdock tea group (59.3 months [95% CI: 54.0–64.7] vs. 45.1 months [95% CI: 37.1–53.0] by the Kaplan-Meier analysis; p = 0.012 by log rank test) than in the control group, although there was no significant preventive effects on the CDB recurrence. This randomized clinical trial demonstrated that daily intake of burdock tea could be an effective strategy for prevention of ACD recurrence, but not for CDB recurrence.

Diverticulosis today

The incidence of diverticulosis and diverticular disease of the colon is increasing worldwide. Although the majority of patients remains asymptomatic long-life, the prevalence of diverticular disease of the colon, including acute diverticulitis, is substantial and is becoming a significant burden on National Health Systems in terms of direct and indirect costs. Fiber, non-absorbable antibiotics and probiotics seem to be effective in treating symptomatic and uncomplicated patients, and 5-aminosalicylic acid might help prevent acute diverticulitis. Unfortunately, robust evidence on the effectiveness of a medical strategy to prevent acute diverticulitis recurrence is still lacking. Focus is now being drawn on identifying a new endoscopic classification of the disease to evaluate the correct therapeutic approach by testing various treatments.

Management of Diverticulitis in 2017

Diverticulitis has become increasingly more common in the 20^th century and is now one of the most frequent indications for gastrointestinal tract-related hospitalizations. The spectrum of clinical presentation can vary widely from mild, uncomplicated disease that can be managed as an outpatient, to complicated diverticulitis with peritonitis and sepsis. Historically, all patients with diverticulitis were managed with, at a minimum, a course of antibiotics, with many patients undergoing urgent or emergent surgery with a sigmoid colectomy, end colostomy, and oversewn rectosigmoid "Hartmann's" stump. However, the treatment paradigm has shifted away from more aggressive surgical management over the years, with recent literature supporting the notion that nonoperative management may lead to equivalent or even superior outcomes in many circumstances. Therefore, the purpose of this review is to summarize and interpret the existing literature on the management of uncomplicated and complicated left-sided diverticulitis in 2017.

Role of Fiber in Symptomatic Uncomplicated Diverticular Disease: A Systematic Review

Symptomatic uncomplicated diverticular disease (SUDD) is a syndrome characterized by recurrent abdominal symptoms in patients with colonic diverticula. There is some evidence that a high-fiber diet or supplemental fibers may reduce symptoms in SUDD patients and a high-fiber diet is commonly suggested for these patients. This systematic review aims to update the evidence on the efficacy of fiber treatment in SUDD, in terms of a reduction in symptoms and the prevention of acute diverticulitis. According to PRISMA, we identified studies on SUDD patients treated with fibers (PubMed and Scopus). The quality of these studies was evaluated by the Jadad scale. The main outcome measures were a reduction of abdominal symptoms and the prevention of acute diverticulitis. Nineteen studies were included, nine with dietary fiber and 10 with supplemental fiber, with a high heterogeneity concerning the quantity and quality of fibers employed. Single studies suggest that fibers, both dietary and supplemental, could be beneficial in SUDD, even if the quality is very low, with just one study yielding an optimal score. The presence of substantial methodological limitations, the heterogeneity of the therapeutic regimens employed, and the lack of ad hoc designed studies, did not permit a summary of the outcome measure. Thus, the benefit of dietary or supplemental fiber in SUDD patients still needs to be established.

Pathophysiology and Therapeutic Strategies for Symptomatic Uncomplicated Diverticular Disease of the Colon

Colonic diverticulosis imposes a significant burden on industrialized societies. The current accepted causes of diverticula formation include low fiber content in the western diet with decreased intestinal content and size of the lumen, leading to the transmission of muscular contraction pressure to the wall of the colon, inducing the formation of diverticula usually at the weakest point of the wall where penetration of the blood vessels occurs. Approximately 20 % of the patients with colonic diverticulosis develop abdominal symptoms (i.e., abdominal pain and discomfort, bloating, constipation, and diarrhea), a condition which is defined as symptomatic uncomplicated diverticular disease (SUDD). The pathogenesis of SUDD symptoms remains uncertain and even less is known about how to adequately manage bowel symptoms. Recently, low-grade inflammation, altered intestinal microbiota, visceral hypersensitivity, and abnormal colonic motility have been identified as factors leading to symptom development, thus changing and improving the therapeutic approach. In this review, a comprehensive search of the literature regarding on SUDD pathogenetic hypotheses and pharmacological strategies was carried out. The pathogenesis of SUDD, although not completely clarified, seems to be related to an interaction between colonic microbiota alterations, and immune, enteric nerve, and muscular system dysfunction (Cuomo et al. in United Eur Gastroenterol J 2:413-442, 2014). Greater understanding of the inflammatory pathways and gut microbiota composition in subjects affected by SUDD has increased therapeutic options, including the use of gut-directed antibiotics, mesalazine, and probiotics (Bianchi et al. in Aliment Pharmacol Ther 33:902-910, 2011; Comparato et al. in Dig Dis Sci 52:2934-2941, 2007; Tursi et al. in Aliment Pharmacol Ther 38:741-751, 2013); however, more research is necessary to validate the safety, effectiveness, and cost-effectiveness of these interventions.

Recent advances in the treatment of colonic diverticular disease and prevention of acute diverticulitis

The incidence of diverticulosis and diverticular disease of the colon is increasing worldwide. Although the majority of patients remains asymptomatic long-life, the prevalence of diverticular disease of the colon, including acute diverticulitis, is substantial and is becoming a significant burden on National Health Systems in terms of direct and indirect costs. Focus is now being drawn on identifying the correct therapeutic approach by testing various treatments. Fiber, non-absorbable antibiotics and probiotics seem to be effective in treating symptomatic and uncomplicated patients, and 5-aminosalicylic acid might help prevent acute diverticulitis. Unfortunately, robust evidence on the effectiveness of a medical strategy to prevent acute diverticulitis recurrence is still lacking. We herein provide a concise review on the effectiveness and future perspectives of these treatments.

[Treatment of the acute diverticulitis: A systematic review]

Acute diverticulitis is a common disease with increasing incidence. In most of cases, diagnosis is made at an uncomplicated stage offering a curative attempt under medical treatment and use of antibiotics. There is a risk of diverticulitis recurrence. Uncomplicated diverticulitis is opposed to complicated forms (perforation, abscess or fistula). Recent insights in the pathophysiology of diverticulitis, the natural history, and treatments have permitted to identify new treatment strategies. For example, the use of antibiotics tends to decrease; surgery is now less invasive, percutaneous drainage is preferred, peritoneal lavage is encouraged. Treatments of the diverticulitis are constantly evolving. In this review, we remind the pathophysiology and natural history, and summarize new recommendations for the medical and surgical treatment of acute diverticulitis.

Review article: the pathophysiology and medical management of diverticulosis and diverticular disease of the colon

BACKGROUND

The incidence of diverticulosis and diverticular disease of the colon, including diverticulitis, is increasing worldwide, and becoming a significant burden on national health systems. Treatment of patients with diverticulosis and DD is generally based on high-fibre diet and antibiotics, respectively. However, new pathophysiological knowledge suggests that further treatment may be useful.

AIM

To review the current treatment of diverticulosis and diverticular disease.

METHODS

A search of PubMed and Medline databases was performed to identify articles relevant to the management of diverticulosis and diverticular disease. Major international conferences were also reviewed.

RESULTS

Two randomised controlled trials (RCT) found the role of antibiotics in managing acute diverticulitis to be questionable, particularly in patients with no complicating comorbidities. One RCT found mesalazine to be effective in preventing acute diverticulitis in patients with symptomatic uncomplicated diverticular disease. The role of rifaximin or mesalazine in preventing diverticulitis recurrence, based on the results of 1 and 4 RCTs, respectively, remains unclear. RCTs found rifaximin and mesalazine to be effective in treating symptomatic uncomplicated diverticular disease. The use of probiotics in diverticular disease and in preventing acute diverticulitis occurrence/recurrence appears promising but unconclusive. Finally, the role of fibre in treating diverticulosis remains unclear.

CONCLUSIONS

Available evidence suggests that antibiotics have a role only in the treatment of complicated diverticulitis. It appears to be some evidence for a role for rifaximin and mesalazine in treating symptomatic uncomplicated diverticular disease. Finally, there is not currently adequate evidence to recommend any medical treatment for the prevention of diverticulitis recurrence.

Systematic review of evidence and consensus on diverticulitis: an analysis of national and international guidelines

AIM

The study aimed to analyse the currently available national and international guidelines for areas of consensus and contrasting recommendations in the treatment of diverticulitis and thereby to design questions for future research.

METHOD

MEDLINE, EMBASE and PubMed were systematically searched for guidelines on diverticular disease and diverticulitis. Inclusion was confined to papers in English and those < 10 years old. The included topics were classified as consensus or controversy between guidelines, and the highest level of evidence was scored as sufficient (Oxford Centre of Evidence-Based Medicine Level of Evidence of 3a or higher) or insufficient.

RESULTS

Six guidelines were included and all topics with recommendations were compared. Overall, in 13 topics consensus was reached and 10 topics were regarded as controversial. In five topics, consensus was reached without sufficient evidence and in three topics there was no evidence and no consensus. Clinical staging, the need for intraluminal imaging, dietary restriction, duration of antibiotic treatment, the protocol for abscess treatment, the need for elective surgery in subgroups of patients, the need for surgery after abscess treatment and the level of the proximal resection margin all lack consensus or evidence.

CONCLUSION

Evidence on the diagnosis and treatment of diverticular disease and diverticulitis ranged from nonexistent to strong, regardless of consensus. The most relevant research questions were identified and proposed as topics for future research.

Italian consensus conference for colonic diverticulosis and diverticular disease

The statements produced by the Consensus Conference on Diverticular Disease promoted by GRIMAD (Gruppo Italiano Malattia Diverticolare, Italian Group on Diverticular Diseases) are reported. Topics such as epidemiology, risk factors, diagnosis, medical and surgical treatment of diverticular disease (DD) in patients with uncomplicated and complicated DD were reviewed by a scientific board of experts who proposed 55 statements graded according to level of evidence and strength of recommendation, and approved by an independent jury. Each topic was explored focusing on the more relevant clinical questions. Comparison and discussion of expert opinions, pertinent statements and replies to specific questions, were presented and approved based on a systematic literature search of the available evidence. Comments were added explaining the basis for grading the evidence, particularly for controversial areas.

Mesalamine did not prevent recurrent diverticulitis in phase 3 controlled trials

BACKGROUND & AIMS

No therapy has been proven to prevent the recurrence of diverticulitis. Mesalamine has shown efficacy in preventing relapse in inflammatory bowel disease, and there is preliminary evidence that it might be effective for diverticular disease. We investigated the efficacy of mesalamine in preventing recurrence of diverticulitis in 2 identical but separate phase 3, randomized, double-blind, placebo-controlled, multicenter trials (identical confirmatory trials were conducted for regulatory reasons).

METHODS

We evaluated the efficacy and safety of multimatrix mesalamine vs placebo in the prevention of recurrent diverticulitis in 590 (PREVENT1) and 592 (PREVENT2) adult patients with ≥1 episodes of acute diverticulitis in the previous 24 months that resolved without surgery. Patients received mesalamine (1.2 g, 2.4 g, or 4.8 g) or placebo once daily for 104 weeks. The primary end point was the proportion of recurrence-free patients at week 104. Diverticulitis recurrence was defined as surgical intervention at any time for diverticular disease or presence of computed tomography scan results demonstrating bowel wall thickening (>5 mm) and/or fat stranding consistent with diverticulitis. For a portion of the study, recurrence also required the presence of abdominal pain and an increase in white blood cells.

RESULTS

Mesalamine did not reduce the rate of diverticulitis recurrence at week 104. Among patients in PREVENT1, 53%-63% did not have disease recurrence, compared with 65% of those given placebo. Among patients in PREVENT2, 59%-69% of patients did not have disease recurrence, compared with 68% of those given placebo. Mesalamine did not reduce time to recurrence, and the proportions of patients requiring surgery were comparable among treatment groups. No new adverse events were identified with mesalamine administration.

CONCLUSIONS

Mesalamine was not superior to placebo in preventing recurrent diverticulitis. Mesalamine is not recommended for this indication. ClinicalTrials.gov ID: NCT00545740 and NCT00545103.

Microencapsulated sodium butyrate administered to patients with diverticulosis decreases incidence of diverticulitis--a prospective randomized study

BACKGROUND

Microencapsulated sodium butyrate (MSB) has been previously associated with anti-inflammatory and regenerative properties regarding large bowel mucosa. We aimed to examine a role of MSB in patients with diverticulosis, hypothesizing its potential for reduction of diverticulitis episodes and diverticulitis prevention.

METHODS

Seventy-three patients with diverticulosis (diagnosed in colonoscopy or/and barium enema or/and CT colography) were recruited for the study and randomized. The investigated group was administered MSB 300 mg daily; the control group was administered placebo. After 12 months, a total of 52 patients completed the study and were subject to analysis (30 subjects and 22 controls). During the study, the number of episodes of diverticulitis (symptomatic diagnosis with acute pain, fever, and leukocytosis), hospitalizations, and surgery performed for diverticulitis were recorded. Additionally, a question regarding subjective improvement of symptoms reflected changes in quality of life during the analysis.

RESULTS

After 12 months, the study group noted a significantly decreased number of diverticulitis episodes in comparison to the control group. The subjective quality of life in the study group was higher than in the control group. There were no side effects of the MSB during the therapy.

CONCLUSIONS

MSB reduces the frequency of diverticulitis episodes, is safe, and improves the quality of life. It can play a role in the prevention of diverticulitis.

Appendicitis/diverticulitis: diagnostics and conservative treatment

Appendicitis and diverticulitis are very common entities that show some similarities in diagnosis and course of disease. Both are widely believed to be simple clinical diagnoses, which is in contrast to scientific evidence. An accurate diagnosis has to describe not only the initial detection, but particularly the severity of the disease. It is based mainly on cross-sectional imaging by ultrasound (US) and computed tomography (CT). Appendectomy is the standard treatment for acute appendicitis and is mandatory in complicated cases. Antibiotic therapy is similarly effective in uncomplicated appendicitis, but long-term results are not sufficiently known. Treatment of diverticulitis is related to the disease status. Complications such as perforation and bleeding require intervention. Uncomplicated diverticulitis as graded by US or CT are subject to conservative management, in the form of outpatient or hospital care. It is an unresolved debate as to whether antibiotic treatment offers benefits. Mesalazine seems at least to improve pain. The real challenge is treatment of recurrent diverticulitis. Lifestyle measures such as nutritional habits and physical activity are found to influence diverticular disease. Besides immunosuppression, obesity is a significant risk factor for complicated diverticulitis. Whether any medication such as chronic antibiotics, probiotics or mesalazine offers benefits is unclear. The indication for sigmoid resection has changed; it is no longer given by the number of attacks, but rather by structural changes as depicted by cross-sectional imaging.

Long-term treatment with mesalazine in patients with symptomatic uncomplicated diverticular disease

The aim of this work was to compare the recurrence of diverticulitis during a 5-year follow-up in a population of patients affected by symptomatic uncomplicated diverticular disease (SUDD), taking either 800 mg of mesalamine b.i.d for 10 days every month or no 5-ASA. Sixty-seven consecutive patients affected by SUDD followed-up every 6 months for 5 years. All patients in this group (M-group) were requested to consume mesalamine 800 mg b.i.d for 10 days every month. A control group (C-group) of 82 subjects with SUDD allocated in an institution for the elderly and taking no 5-ASA medications was also followed-up for the same period. As a result in the M-group 14.9% of patients did not complete the follow-up, and diverticulitis developed in two patients (4%; 95% CI 1.1-13.5). In the C-group 6.1% patients did not complete the follow-up, and diverticulitis developed in 8 patients (10.4%; 95% CI 5.4-19.2). The difference between the two groups was not significant (difference = -6.4%; 95% CI -15.6 to 4.3; log rank test: p = 0.1256). Cyclic treatment with mesalazine seems to be clinical, although not statistically effective in reducing the incidence of diverticulitis. In future well-designed RCTs are necessary to demonstrate the therapeutic gain of the use of mesalazine, if any, in the management of patients with SUDD.

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. Orv. Hetil., 2012, 153, 205–213.

A systematic review of high-fibre dietary therapy in diverticular disease

PURPOSE

The exact pathogenesis of diverticular disease of the sigmoid colon is not well established. However, the hypothesis that a low-fibre diet may result in diverticulosis and a high-fibre diet will prevent symptoms or complications of diverticular disease is widely accepted. The aim of this review is to assess whether a high-fibre diet can improve symptoms and/or prevent complications of diverticular disease of the sigmoid colon and/or prevent recurrent diverticulitis after a primary episode.

METHODS

Clinical studies were eligible for inclusion if they assessed the treatment of diverticular disease or the prevention of recurrent diverticulitis with a high-fibre diet. The following exclusion criteria were used for study selection: studies without comparison of the patient group with a control group.

RESULTS

No studies concerning prevention of recurrent diverticulitis with a high-fibre diet met our inclusion criteria. Three randomised controlled trials (RCT) and one case-control study were included in this systematic review. One RCT of moderate quality showed no difference in the primary endpoints. A second RCT of moderate quality and the case-control study found a significant difference in favour of a high-fibre diet in the treatment of symptomatic diverticular disease. The third RCT of moderate quality found a significant difference in favour of methylcellulose (fibre supplement). This study also showed a placebo effect.

CONCLUSION

High-quality evidence for a high-fibre diet in the treatment of diverticular disease is lacking, and most recommendations are based on inconsistent level 2 and mostly level 3 evidence. Nevertheless, high-fibre diet is still recommended in several guidelines.

Current status of the treatment of acute colonic diverticulitis: a systematic review

AIM

This paper addresses the current status of the treatment of acute colonic diverticulitis by an evidence-based review.

METHOD

A systematic search in PUBMED, MEDLINE, EMBASE and Google scholar on colonic diverticulitis was performed. Diagnostic tools, randomized controlled trials, non-randomized comparative studies, observational epidemiological studies, national and international guidelines, reviews of observational studies on elective and emergency surgical treatment of diverticulitis, and studies of prognostic significance were reviewed. Criteria for eligibility of the studies were diagnosis and classification, medical treatment, inpatients and outpatients, diverticulitis in young patients, immunosuppression, recurrence, elective resection, emergency surgery, and predictive factors.

RESULTS

Some 92 publications were selected for comprehensive review. The review highlighted that computed tomography is the most effective test in the diagnosis and staging of acute diverticulitis; outpatient treatment can be performed for uncomplicated diverticulitis in patients without associated comorbidities; conservative treatment is aimed at those patients with uncomplicated acute diverticulitis; elective surgery must be done on an individual basis; laparoscopic approach for elective treatment of diverticulitis is appropriate but may be technically complex; in perforated diverticulitis, resection with primary anastomosis is a safe procedure that requires experience and should take into account strict exclusion criteria.

CONCLUSION

The heterogeneity of patients with colonic diverticular disease means that both elective and urgent treatment should be tailored on an individual basis.

Treatment of diverticular disease of the colon and prevention of acute diverticulitis: a systematic review

BACKGROUND

Diverticular disease of the colon is a common disorder, characterized by recurrent symptoms and complications such as diverticulitis, requiring hospital admissions and surgery.

OBJECTIVE

This study aimed to systematically review the evidence for medical therapy of diverticular disease in reducing symptoms and preventing acute diverticulitis.

DATA SOURCES

MEDLINE and Embase databases (1966 to February 2010).

STUDY SELECTION

The studies selected were prospective clinical trials on uncomplicated diverticular disease of the colon.

INTERVENTIONS

Four investigators independently reviewed articles, extracted data, and assessed study quality according to standardized criteria.

MAIN OUTCOME MEASURES

The main outcomes measured were improvement in symptoms, complete remission of symptoms, and prevention of acute diverticulitis.

RESULTS

We identified 31 studies, including 6 placebo-controlled trials. The methodological quality of these studies was suboptimal. Only 10 trials provided a detailed description of the patient history, 8 assessed symptoms by the use of a validated questionnaire, and 14 appropriately defined inclusion and exclusion criteria. Only one long-term double-blind placebo-controlled study was identified. This reported a significant improvement in symptoms and greater prevalence of symptom-free patients at 1 year with fiber plus rifaximin in comparison with fiber alone. The efficacy of treatment in preventing acute diverticulitis was evaluated in 11 randomized trials. Four trials compared rifaximin plus fiber vs fiber alone and failed to show a significant difference between treatments. However, cumulative data from these trials revealed a significant benefit following rifaximin and fiber (1-year rate of acute diverticulitis: 11/970 (1.1%) vs 20/690 (2.9%); P = .012), but with a number needed to treat of 57, to prevent an attack of acute diverticulitis.

LIMITATIONS

: Heterogeneity of the study design, patients' characteristics, regimens and combination of studied treatment, and outcome reporting precluded the pooling of results and limited interpretation.

CONCLUSIONS

The treatment for diverticular disease relies mainly on data from uncontrolled studies. Treatment showed some evidence of improvement in symptoms, but its role in the prevention of acute diverticulitis remains to be defined.

The medical and nonoperative treatment of diverticulitis

The success of medical management for diverticular disease depends on the patient's presentation and degree of response to treatment. The patient's presentation can be grouped into categories using classification systems such as the modified Hinchey system. Clinical presentation and diagnostic studies help to group patients. Mild disease can often be managed with oral antibiotics as an outpatient; more severe disease requires hospitalization, bowel rest, and intravenous antibiotics. Interventions such as percutaneous drainage of associated abscesses may allow successful medical management. Probiotics and antiinflammatories may have a supportive role. Indications for elective resections are discussed.

Diverticular disease: epidemiology and management

Diverticular disease of the colon is among the most prevalent conditions in western society and is among the leading reasons for outpatient visits and causes of hospitalization. While previously considered to be a disease primarily affecting the elderly, there is increasing incidence among individuals younger than 40 years of age. Diverticular disease most frequently presents as uncomplicated diverticulitis, and the cornerstone of management is antibiotic therapy and bowel rest. Segmental colitis associated with diverticula shares common histopathological features with inflammatory bowel disease and may benefit from treatment with 5-aminosalicylates. Surgical management may be required for patients with recurrent diverticulitis or one of its complications including peridiverticular abscess, perforation, fistulizing disease, and strictures and ⁄ or obstruction.

Prospective randomized clinical trial assessing the efficacy of a short course of intravenously administered amoxicillin plus clavulanic acid followed by oral antibiotic in patients with uncomplicated acute diverticulitis

INTRODUCTION

Medical treatment of uncomplicated acute diverticulitis is not standardized, and there is an enormous diversity in clinical practice. Our aim was to demonstrate that uncomplicated diverticulitis can be managed with orally administered amoxicillin plus clavulanic acid and a short hospital admission.

METHODS

A prospective randomized trial was established to compare patients with uncomplicated diverticulitis who received oral antibiotic after a short course of intravenous antibiotic with those who received intravenous antibiotic for a longer period. The antibiotic treatment consisted of amoxicillin plus clavulanic acid 1 g every 8 h. We included 50 patients, 25 in each group. Patients in group 1 began oral antibiotic as soon as they improved and were discharged the day after. Patients in group 2 received intravenous antibiotic for 7 days. Both groups received oral antibiotic at discharge. The endpoint of the study was "failure of treatment," which was defined as the impossibility of discharging on the expected day, emergency admission, or hospital readmission.

RESULTS

Both groups were comparable in patient demographics and clinical characteristics. Most patients clearly improved between 24 and 48 h after admission. There were no significant differences between the groups when comparing failure of treatment. Treatment of patients in group 1 represented a savings in hospitalization costs of 1,244<euro> per patient.

CONCLUSIONS

Most patients with uncomplicated diverticulitis can be managed safely with oral antibiotic; thus, a very short hospital stay is a safe option.

Rifaximin in the management of colonic diverticular disease

Rifaximin is a rifamycin derivative that acts by inhibiting bacterial RNA synthesis. Since it is virtually unabsorbed after oral administration, its bioavailability within the GI tract is high, with intraluminal and fecal drug concentrations largely exceeding the minimum inhibitory concentration values observed in vitro against a broad spectrum of bacteria, including Gram-positive and Gram-negative bacteria, both aerobes and anaerobes. The GI tract, therefore, represents the primary therapeutic target and the disorders in which intestinal bacteria have a pathogenic role represent the main indication. This is the case with colonic diverticular disease. As a consequence, the broad antibacterial activity of rifaximin appears to be of value in the treatment of this clinical condition. Clinical trials have provided evidence of the substantial benefit of rifaximin in diverticular disease. Indeed, available data show the efficacy of the drug in achieving symptomatic relief in patients with uncomplicated disease. A therapeutic gain of approximately 30%, compared with fiber supplementation only, can be expected after cyclic administration of rifaximin for 12 months. However, its value in the prevention of inflammatory complications of the disease needs to be further explored. Recent studies have shown some evidence of synergy between rifaximin and mesalazine and suggest that a combined treatment could be worthwhile in selected subsets of patients with diverticular disease.

Treatment options for uncomplicated diverticular disease of the colon

Patients affected by uncomplicated diverticular disease (DD) suffer from colicky, unexplained, recurrent, and short-lived but often debilitating abdominal pain and alteration in bowel habit. Although the goals of therapy, such as to improve symptoms and to prevent both recurrent attacks and complications, are clearly established, the standard approach remains still debated. We examined the current scientific evidence supporting the different treatment options for uncomplicated DD. An internet-based search strategy of the Medline and Science Citation Index was performed using the keywords: diverticulosis, DD, fiber, bran, diet, antibiotics, rifaximin, probiotics, prebiotics, bacteria, lactobacillus, bifidobacteria, 5-aminosalicylic acid, sulfasalazine, mesalazine, balsalazide in various combinations to select randomized trials published in the English language between January 1966 and March 2009. The use of fiber and nonabsorbable antibiotics is supported by the existence of randomized controlled studies. More recently, alternative treatments, such as probiotics and mesalazine have been proposed even if no definite data are available. Although the preliminary results seem to be promising, randomized, placebo-controlled studies are needed before new therapies can be recommended in the management of uncomplicated DD.

Diet, ageing and genetic factors in the pathogenesis of diverticular disease

Diverticular disease (DD) is an age-related disorder of the large bowel which may affect half of the population over the age of 65 in the UK. This high prevalence ranks it as one of the most common bowel disorders in western nations. The majority of patients remain asymptomatic but there are associated life-threatening co-morbidities, which, given the large numbers of people with DD, translates into a considerable number of deaths per annum. Despite this public health burden, relatively little seems to be known about either the mechanisms of development or causality. In the 1970s, a model of DD formulated the concept that diverticula occur as a consequence of pressure-induced damage to the colon wall amongst those with a low intake of dietary fiber. In this review, we have examined the evidence regarding the influence of ageing, diet, inflammation and genetics on DD development. We argue that the evidence supporting the barotrauma hypothesis is largely anecdotal. We have also identified several gaps in the knowledge base which need to be filled before we can complete a model for the etiology of diverticular disease.

Emerging therapies for diverticular disease of the colon

Diverticular disease (DD) of the colon is common. This paper reviews the evidence supporting the role of some of the conventional medical therapies such as fiber and nonabsorbable antibiotics in the treatment of DD. More importantly, it will review the emerging body of evidence supporting the use of 5-aminosalicylic acid and probiotics for symptomatic or complicated DD. Possible mechanisms supporting the role of 5-aminosalicylates will also be discussed. On the basis of strength of the evidence supporting each medical intervention, recommendations will be graded in an evidence-based fashion. Finally, an evidence-based algorithmic approach is proposed for the medical management of DD. This paper does not discuss the use of absorbable antibiotics such as ciprofloxin and metronidazole, which are discussed in all standard textbooks. The purpose of this paper is to discuss newer recommendations.

Colonic diverticular disease

INTRODUCTION

Diverticula (mucosal outpouching through the wall of the colon) affect over 5% of adults aged 40 years and older, but only 10-25% of affected people will develop symptoms such as lower abdominal pain. Recurrent symptoms are common, and 5% of people with diverticula eventually develop complications such as perforation, obstruction, haemorrhage, fistulae, or abscesses.

METHODS AND OUTCOMES

We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of: treatments for uncomplicated diverticular disease; treatments to prevent complications; and treatments for acute diverticulitis? We searched: Medline, Embase, The Cochrane Library and other important databases up to July 2006 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

RESULTS

We found 13 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.

CONCLUSIONS

In this systematic review we present information relating to the effectiveness and safety of the following interventions: antispasmodics, bran, elective surgery, increasing fibre intake, ispaghula husk, lactulose, medical treatment, mesalazine, methylcellulose, rifaximin, surgery.

Epidemiology and management of diverticular disease of the colon

The aim of this review is mainly to show the high prevalence of diverticulosis and the clinical relevance of uncomplicated and complicated diverticular disease worldwide. The prevalence of diverticular disease is directly related to the aging of the population and in western countries is diagnosed in approximately 50–65% of adult subjects. The often more frequent adoption of an incorrect dietary style, such as a low-fiber diet, and the progressive increase in the average age of western populations will increase the prevalence of this pathology and the economic burden for health systems even more so. Furthermore, the management of uncomplicated diverticular disease, segmental colitis associated to diverticula and diverticulitis, which represent the different manifestations of the symptomatic spectrum of colonic diverticulosis, are reported.

Controversies in the surgical management of sigmoid diverticulitis

The timing and appropriateness of surgical treatment of sigmoid diverticular disease remain a topic of controversy. We have reviewed the current literature on this topic, focusing on issues related to the indications and types of surgery. Current evidence would suggest that elective surgery for diverticulitis can be avoided in patients with uncomplicated disease, regardless of the number of recurrent episodes. Furthermore, the need for elective surgery should not be influenced by the age of the patient. Operation should be undertaken in patients with severe attacks, as determined by their clinical and radiological evaluation.

Review article: uncomplicated diverticular disease of the colon

Diverticular disease of the colon is the fifth most important gastrointestinal disease in terms of direct and indirect health care costs in western countries. Uncomplicated diverticular disease is defined as the presence of diverticula in the absence of complications such as perforation, fistula, obstruction and/or bleeding. The distribution of diverticula along the colon varies worldwide being almost always left-sided and directly related to age in western countries and right-sided where diet is rich in fibre. The pathophysiology of diverticular disease is complex and relates to abnormal colonic motility, changes in the colonic wall, chronic mucosal low-grade inflammation, imbalance in colonic microflora and visceral hypersensitivity. Moreover, there can be genetic factors involved in the development of colonic diverticula. The use of non-absorbable antibiotics is the mainstay of therapy in patients with mild to moderate symptoms, and the effect of fibre-supplementation alone does not appear to be significantly different from placebo, although no definite data are available. More recently, alternative treatments have been reported. Mesalazine acts as a local mucosal immunomodulator and has been shown to improve symptoms and prevent recurrence of diverticulitis. In addition, probiotics have also been shown to be beneficial by re-establishing a normal gut microflora. In this study, the current literature on uncomplicated diverticular disease of the colon is reviewed.

Divertikulose und Divertikulitis

Alterations in the colon wall, motility disorders, and certain nutritional habits are the essential factors in the development of colon diverticula. Thus, with advancing age this results in a high incidence in Western industrialized countries. The clinical picture is usually one of symptom-free diverticulosis. Diverticular disease can be associated with minor symptoms, but in complicated cases with diverticulitis and diverticular hemorrhage, it is potentially fatal. Further complications include abscess formation, fistula development, and obstruction. Barium double-contrast imaging exhibits the highest diagnostic sensitivity in diverticulosis but is contraindicated in cases of suspected complicated diverticular disease due to the danger of perforation. In these instances, sonography, computed tomography, or magnetic resonance imaging are performed. For diverticular hemorrhage, coloscopy not only represents a possible diagnostic tool but also a therapeutic option for various techniques of hemostasis. Treatment of diverticulitis and its complications requires careful consideration of conservative and surgical approaches and close interdisciplinary cooperation.

Diverticular disease of the colon

Colonic diverticulosis refers to small outpouchings from the colonic lumen due to mucosal herniation through the colonic wall at sites of vascular perforation. Abnormal colonic motility and inadequate intake of dietary fibre have been implicated in its pathogenesis. This acquired abnormality is typically found in developed countries, and its prevalence rises with age. Most patients affected will remain entirely asymptomatic; however, 10-20% of those affected can manifest clinical syndromes, mainly diverticulitis and diverticular haemorrhage. As our elderly population grows, we can anticipate a concomitant rise in the number of patients with diverticular disease. Here, we review the incidence, pathophysiology, clinical presentation, and management of diverticular disease of the colon and its complications.

Evaluation of drug treatment in irritable bowel syndrome

The irritable bowel syndrome (IBS) remains a therapeutic challenge in part because of the limited understanding of the pathophysiology. The placebo response rate varies in randomized controlled trials from 20 to 70%, and can persist for up to at least 1 year. It is contentious whether dietary fibre and bulking agents relieve the symptoms of IBS; constipation probably improves. Anticholinergic and antispasmodic agents are of questionable benefit in IBS despite positive meta-analyses of poor quality trials. A meta-analysis concluded that the tricyclic antidepressants were superior to placebo in IBS, although the individual trial results were variable. Selective serotonin reuptake inhibitors are of uncertain benefit. Laxatives are used for constipation but probably poorly control the IBS symptom complex. Loperamide is superior to placebo in improvement of diarrhoea but not abdominal pain in IBS. Tegaserod is a well- tolerated aminoguanidine indole derivative of serotonin that is a partial 5HT4-receptor agonist with prokinetic properties; a therapeutic gain over placebo of 5% to 15% has been observed in constipation-predominant IBS in females. Alosetron is a 5HT3-receptor antagonist that is efficacious in females with diarrhoea-predominant IBS, with a 12% to 17% therapeutic gain; the risk of ischaemic colitis is 1 in 350, with very severe constipation occurring in about 1 in 1000. Optimizing study design remains a challenge in IBS. New visceral analgesic and motility modifying agents, as well as anti-inflammatory agents are in trials, and hopefully additional efficacious therapeutic options for patients with IBS will soon emerge.

Diverticular disease of the colon: New perspectives in symptom development and treatment

Diverticular disease of the colon is a common disease worldwide. Although the disease is asymptomatic in about 70%-80% of patients, it represents, at least in Western countries, one of the most important gastrointestinal diseases in terms of direct and indirect health costs. Pathogenesis of the disease is still unknown. However, it is the result of complex interactions between colonic structure, intestinal motility, diet and genetic factors. Whilst efficacious preventive strategies remain to be identified, fibre supplementation in the diet is recommended. Why symptoms develop is still unclear. Results of recent experimental studies on irritable bowel syndrome speculated that low grade inflammation of colonic mucosa, induced by changes in bacterial microflora, could affect the enteric nervous system, which is crucial for normal gut function, thus favouring symptom development. This hypothesis could be extrapolated also for diverticular disease, since bacterial overgrowth is present, at least in a subgroup of patients. These perspectives on symptom development are reviewed and new therapeutic approaches are hypothesized.

Dietary fibre: a roughage guide

The concept of dietary fibre is a complex one that incorporates the physical and physiological functions of fibre and its effects both systemically and local to the gastro-intestinal tract. Dietary fibre can be usefully classified according to its solubility and fermentability, which allows rational clinical application. Fibres may act in several ways including by gel-forming effects in the stomach and small intestine, by its fermentation by colonic bacteria, by a 'mop and sponge' effect, and via concomitant changes in other aspects of the diet. These actions lead to potentially beneficial effects in the gastro-intestinal tract and systemically, such as lowering serum cholesterol and improving glycaemic control. Dietary fibre has been implicated in multiple clinical situations but, although an extensive literature on putative actions and proposed physiological bases is available, high-level evidence of efficacy is limited. Nevertheless, encouraging the intake of a high-fibre diet is likely to have a range of health benefits and physicians are encouraged to follow simple practical guidelines in their everyday practice.

Medical management of diverticular disease

Diverticular disease is a common disorder affecting 30-55% of the population in the developed world. It has been described as "a deficiency disease of Western civilization", a theory that has been proposed since it was observed that diverticular disease was uncommon in African and other developing countries where dietary fibre consumption was high. At the turn of the century the medical treatment of colonic diverticulosis involved the avoidance of "roughage", which was felt to exacerbate the problem. However, the use of high fibre diets in the prevention and treatment of the symptoms of diverticular disease has now become commonplace, and the development of this practice is discussed in this chapter.

Diverticular disease in the elderly

Diverticular disease is common among the elderly. Because of the advanced age and muted symptoms and signs of many of those affected, diagnosis can be difficult. Consequently, great demands are placed on the physician to diagnose and treat clinically evident diverticular disease. Endoscopic, radiologic, and surgical advances have increased the availability of more definitive therapies for patients with complicated diverticular disease and diverticular hemorrhage.

Diverticular disease of the colon

Diverticular disease of the colon is quite common in developed countries, and its prevalence increases with age. Although present in perhaps two thirds of the elderly population, the large majority of patients will remain entirely asymptomatic. Nonetheless, an estimated 20% of those affected may manifest clinical illness, mainly diverticulitis, with its potential complications of abscesses, fistulas, and obstruction, as well as lower intestinal hemorrhage. The purpose of this report is to review our understanding of the epidemiology, pathophysiology, clinical presentation, and treatment options for this disorder.