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

Unmet needs in treatment of symptomatic uncomplicated diverticular disease and prevention of recurrent acute diverticulitis: a scoping review

Background

Diverticular disease (DD) represents a common gastrointestinal condition that poses a heavy burden on healthcare systems worldwide. A high degree of uncertainty surrounds the therapeutic approaches for the control of symptoms in patients with symptomatic uncomplicated diverticular disease (SUDD) and primary and secondary prevention of diverticulitis and its consequences.

Objectives

To review the current knowledge and discuss the unmet needs regarding the management of SUDD and the prevention of acute diverticulitis.

Eligibility criteria

Randomized trials, observational studies, and systematic reviews on lifestyle/dietary interventions and medical treatment (rifaximin, mesalazine, and probiotics) of SUDD or prevention of acute diverticulitis.

Sources of evidence

The literature search was performed from inception to April 2023, without language restriction, following the modified Preferred Reporting Items for Systematic review and Meta-Analyses (PRISMA) reporting guidelines. References of the papers selected were checked to identify additional papers of potential interest. The final list of references was evaluated by a panel of experts, who were asked to check for any lack of relevant studies.

Charting methods

Information on patient population, study design, intervention, control group, duration of the observation, and outcomes assessed was collected by two authors independently.

Results

The review shows a high degree of uncertainty about therapeutic interventions, both dietary/lifestyle and pharmacological, in patients with SUDD, because of the scarcity and weakness of existing evidence. Available studies are generally of low quality, heterogeneous, and outdated, precluding the possibility to draw robust conclusions. Similarly, acute diverticulitis prevention has been seldom investigated, and there is a substantial lack of evidence supporting the role of dietary/lifestyle or pharmacological approaches to reduce the risk of diverticulitis.

Conclusion

The lack of robust evidence regarding therapeutic options for gastrointestinal symptoms in SUDD patients and for primary and secondary prevention of acute diverticulitis remains an important unmet need in the management of DD.

The role of microbiota and its modulation in colonic diverticular disease

BACKGROUND

Diverticular disease (DD) is a common condition in Western countries. The role of microbiota in the pathogenesis of DD and its related symptoms has been frequently postulated since most complications of this disease are bacteria-driven and most therapies rely on microbiota modulation. Preliminary data showed fecal microbial imbalance in patients with DD, particularly when symptomatic, with an increase of pro-inflammatory and potentially pathogenetic bacteria. In addition, bacterial metabolic markers can mirror specific pathways of the disease and may be even used for monitoring treatment effects. All treatments currently suggested for DD can affect microbiota structure and metabolome compositions.

PURPOSE

Sparse evidence is available linking gut microbiota perturbations, diverticular disease pathophysiology, and symptom development. We aimed to summarize the available knowledge on gut microbiota evaluation in diverticular disease, with a focus on symptomatic uncomplicated DD, and the relative treatment strategies.

Colonic diverticular bleeding: An update on pathogenesis and management

Colonic diverticular bleeding is the most common cause of lower gastrointestinal (GI) bleeding, which can be life-threatening and frequently recurrent. In recent years, the prevalence of diverticulosis has increased in developed countries, with a documented incidence of 50% in patients older than 60 years. Based on the evidence, the use of anticoagulants and/or antiplatelets in the elderly population has resulted in an increased incidence of acute diverticular bleeding. According to the literature, about 50% of patients with diverticular bleeding require a blood transfusion, and 18% - 53% need emergency surgery. Although endoscopic identification of the culprit diverticula and appropriate intervention is a challenge, the newer treatment modality, over-the-scope clip method (OTSC) has been demonstrated to be an effective endoscopic hemostatic method in severe diverticular bleeding, especially in cases of rebleeding after first-line conventional endoscopic procedures. In this review, we summarize the pathophysiology of colonic diverticulosis and diverticular bleeding, recent evidence in its management, and existing theories on various preventive strategies to control diverticular bleeding. We also discuss the efficacy and treatment outcome of the OTSC technique in controlling diverticular bleeding.

Symptomatic Uncomplicated Diverticular Disease (SUDD): Practical Guidance and Challenges for Clinical Management

Symptomatic Uncomplicated Diverticular Disease (SUDD) is a syndrome within the diverticular disease spectrum, characterized by local abdominal pain with bowel movement changes but without systemic inflammation. This narrative review reports current knowledge, delivers practical guidance, and reveals challenges for the clinical management of SUDD. A broad and common consensus on the definition of SUDD is still needed. However, it is mainly considered a chronic condition that impairs quality of life (QoL) and is characterized by persistent left lower quadrant abdominal pain with bowel movement changes (eg, diarrhea) and low-grade inflammation (eg, elevated calprotectin) but without systemic inflammation. Age, genetic predisposition, obesity, physical inactivity, low-fiber diet, and smoking are considered risk factors. The pathogenesis of SUDD is not entirely clarified. It seems to result from an interaction between fecal microbiota alterations, neuro-immune enteric interactions, and muscular system dysfunction associated with a low-grade and local inflammatory state. At diagnosis, it is essential to assess baseline clinical and Quality of Life (QoL) scores to evaluate treatment efficacy and, ideally, to enroll patients in cohort studies, clinical trials, or registries. SUDD treatments aim to improve symptoms and QoL, prevent recurrence, and avoid disease progression and complications. An overall healthy lifestyle - physical activity and a high-fiber diet, with a focus on whole grains, fruits, and vegetables - is encouraged. Probiotics could effectively reduce symptoms in patients with SUDD, but their utility is missing adequate evidence. Using Rifaximin plus fiber and Mesalazine offers potential in controlling symptoms in patients with SUDD and might prevent acute diverticulitis. Surgery could be considered in patients with medical treatment failure and persistently impaired QoL. Still, studies with well-defined diagnostic criteria for SUDD that evaluate the safety, QoL, effectiveness, and cost-effectiveness of these interventions using standard scores and comparable outcomes are needed.

German guideline diverticular disease/diverticulitis: Part II: Conservative, interventional and surgical management

Diverticulosis and diverticular disease are ranked among the most common gastroenterological diseases and conditions. While for many years diverticulitis was found to be mainly an event occurring in the elder population, more recent work in epidemiology demonstrates increasing frequency in younger subjects. In addition, there is a noticeable trend towards more complicated disease. This may explain the significant increase in hospitalisations observed in recent years. It is not a surprise that the number of scientific studies addressing the clinical and socioeconomic consequences in the field is increasing. As a result, diagnosis and conservative as well as surgical management have changed in recent years. Diverticulosis, diverticular disease and diverticulitis are a complex entity and apparently an interdisciplinary challenge. To meet theses considerations the German Societies for Gastroenterology and Visceral Surgery decided to create joint guidelines addressing all aspects in a truely interdisciplinary fashion. The aim of the guideline is to summarise and to evaluate the current state of knowledge on diverticulosis and diverticular disease and to develop statements as well as recommendations to all physicians involved in the management of patients with diverticular disease.

Diverticulitis during pregnancy: A review of the reported cases

BACKGROUND

Diverticular disease of the colon represents a common clinical condition in the western world. Its prevalence increases with age and only 5% of cases occur in adults younger than 40 years of age, making it a rare condition during pregnancy. The aim of this review was to provide an overview of the reported cases of diverticulitis during pregnancy.

METHODS

We conducted a systematic review of the literature based on preferred reporting items for systematic review and meta-analysis (PRISMA) guidelines. We searched three different electronic databases namely PubMed, Scopus and Web of Science from inception to December 2021. Literature search and data extraction were completed in duplicates.

RESULTS

The initial search yielded 564 articles from which 12 were finally included in our review. Ten articles were case reports and two were observational studies. The mean age of the cases was 34 years. The presenting complain was provided for 11 cases. The majority of the patients (10/11, 91%) presented with abdominal pain located mainly on the left (6/11, 55%) or right (4/11, 36%) iliac fossa. The most common diagnostic modality used for the diagnosis of the condition was ultrasonography in nine cases (9/12, 75%) followed by magnetic resonance imaging (MRI) in two cases (2/12, 17%). In spite of clinical and radiological evaluation, the initial diagnosis was inaccurate in seven cases (7/12, 58%). The therapeutic approach was available for 11 cases and it was based on the administration of intravenous antibiotics in six cases (6/11, 55%) and surgical management in five cases (5/11, 45%). Data for the type of delivery was provided in nine studies with five patients (5/9, 56%) delivering vaginally and four patients (4/9, 44%) delivering with cesarean section.

CONCLUSION

As advanced maternal age becomes more common, the frequency of diverticulitis in pregnancy may increase. Although available guidelines do not exist, the clinical awareness, early recognition of the disorder, using diagnostic modalities such as ultrasound and MRI, and rapid therapeutic approach with antibiotics, may improve maternal and neonatal outcomes.

Evaluation and Management After Acute Left-Sided Colonic Diverticulitis : A Systematic Review

BACKGROUND

The value of interventions used after acute colonic diverticulitis is unclear.

PURPOSE

To evaluate postdiverticulitis colonoscopy and interventions to prevent recurrent diverticulitis.

DATA SOURCES

MEDLINE, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Embase, CINAHL, and ClinicalTrials.gov from 1 January 1990 through 16 November 2020.

STUDY SELECTION

Comparative studies of interventions of interest reporting critical or important outcomes, and larger single-group studies to evaluate prevalence of colonoscopy findings and harms.

DATA EXTRACTION

6 researchers extracted study data and risk of bias. The team assessed strength of evidence.

DATA SYNTHESIS

19 studies evaluated colonoscopy. Risk for prevalent colorectal cancer (CRC) compared with the general population is unclear. Based on low-strength evidence, long-term CRC diagnosis is similar with or without colonoscopy. High-strength evidence indicates that risk for prevalent CRC is higher among patients with complicated diverticulitis and colonoscopy complications are rare. Based on high-strength evidence, mesalamine does not reduce recurrence risk (6 randomized controlled trials [RCTs]). Evidence on other nonsurgical interventions is insufficient. For patients with prior complicated or smoldering or frequently recurrent diverticulitis, elective surgery is associated with reduced recurrence (3 studies; high strength). In 19 studies, serious surgical complications were uncommon.

LIMITATIONS

Few RCTs provided evidence. Heterogeneity of treatment effect was not adequately assessed.

CONCLUSION

It is unclear whether patients with recent acute diverticulitis are at increased risk for prevalent CRC, but those with complicated diverticulitis are at increased risk. Mesalamine is ineffective in preventing recurrence; other nonsurgical treatments have inadequate evidence. Elective surgery reduces recurrence in patients with prior complicated or smoldering or frequently recurrent diverticulitis, but it is unclear which of these patients may benefit most.

PRIMARY FUNDING SOURCE

Agency for Healthcare Research and Quality and American College of Physicians. (PROSPERO: CRD42020151246).

Updates in the understanding and management of diverticular disease

PURPOSE OF REVIEW

Diverticulosis leads to significant morbidity and mortality and is increasing in prevalence worldwide. In this paper, we review the clinical features, diagnosis, and management of diverticular disorders, followed by a discussion of recent updates and changes in the clinical approach to diverticular disease.

RECENT FINDINGS

Recent literature suggests that antibiotics are likely not necessary for low-risk patients with acute uncomplicated diverticulitis, and not all patients with recurrent diverticulitis require colectomy. Dietary restrictions do not prevent recurrent diverticulitis. Visceral hypersensitivity is increasingly being recognized as a cause of persistent abdominal pain after acute diverticulitis and should be considered along with chronic smoldering diverticulitis, segmental colitis associated with diverticula, and symptomatic uncomplicated diverticular disease.

SUMMARY

Clinicians should be aware that traditionally held assumptions regarding the prevention and management of diverticular disorders have recently been called into question and should adjust their clinical practice accordingly.

Role of Dietary Habits in the Prevention of Diverticular Disease Complications: A Systematic Review

Recent evidence showed that dietary habits play a role as risk factors for the development of diverticular complications. This systematic review aims to assess the effect of dietary habits in the prevention of diverticula complications (i.e., acute diverticulitis and diverticula bleeding) in patients with diverticula disease. PubMed and Scopus databases were searched up to 19 January 2021, 330 records were identified, and 8 articles met the eligibility criteria and were subjected to data extraction. The quality of the studies was evaluated by the Newcastle-Ottawa quality assessment form. No study meets the criteria for being a high-quality study. A high intake of fiber was associated to a decreased risk of diverticulitis or hospitalization due to diverticular disease, with a protective effect for fruits and cereal fiber, but not for vegetable fiber; whereas, a high red meat consumption and a generally Western dietary pattern were associated with an increased risk of diverticulitis. Alcohol use seemed to be associated to diverticular bleeding, but not to recurrent diverticulitis or diverticular complications. Further high-quality studies are needed to better define these associations. It is mandatory to ascertain the role of dietary habits for the development of recurrent acute diverticulitis and diverticular bleeding.

Management of symptomatic uncomplicated diverticular colon disease: A systematic review of diagnosis and treatment

Symptomatic uncomplicated diverticular colon disease (SUDCD) is a highly prevalent disease in our setting, which significantly affects the quality of life of patients. Recent changes in understanding the natural history of this disease and technological and pharmacological advances have increased the available options for both diagnosis and treatment. However, consensus regarding the use of these options is scarce and sometimes lacks scientific evidence. The objective of this systematic review is to clarify the existing scientific evidence and analyse the use of the different diagnostic and therapeutic options for SUDCD, comparing their advantages and disadvantages, to finally suggest a diagnostic-therapeutic algorithm for this pathology and, at the same time, propose new research questions.

Drains, Germs, or Steel: Multidisciplinary Management of Acute Colonic Diverticulitis

The medical and surgical management of uncomplicated diverticulitis has changed over the last several years. Although immunocompetent patients or those without comorbidities can be treated with antibiotics as an outpatient, the efficacy of high-fiber intake or drugs such as mesalamine or rifaximin is not yet clearly established in the treatment of acute episodes and in the prevention of recurrences. On the other hand, the choice between antibiotic treatment and percutaneous drainage is not always obvious in diverticulitis complicated by abscess formation, especially for larger abscesses; although the results of studies comparing the two approaches remain controversial, surgery must be pursued for abscesses > 8 cm. For emergency surgery, the debate is still ongoing regarding laparoscopic lavage and surgical resection followed by primary anastomosis, since for both approaches the published reports are not in agreement regarding possible benefits. Therefore, these approaches are recommended only for selected patients under the care of experienced surgeons. Also, the contribution of elective surgery toward the overall approach has been revised; currently, it is reserved primarily for patients with a high risk of recurrence and whenever more conservative treatments were not effective.

Computational analysis of mechanical stress in colonic diverticulosis

Diverticulosis results from the development of pouch-like structures, called diverticula, over the colon. The etiology of the disease is poorly understood resulting in a lack of effective treatment approaches. It is well known that mechanical stress plays a major role in tissue remodeling, yet its role in diverticulosis has not been studied. Here, we used computational mechanics to investigate changes in stress distribution engendered over the colon tissue by the presence of a pouch-like structure. The objectives of the study were twofold: (1) observe how stress distribution changes around a single pouch and (2) evaluate how stress elevation correlates with the size of the pouch. Results showed that high stresses are concentrated around the neck of a pouch, and their values and propagation increase with the size of the pouch neck rather than the pouch surface area. These findings suggest that stress distribution may change in diverticulosis and a vicious cycle may occur where pouch size increases due to stress elevation, which in turn elevates stress further and so on. Significant luminal pressure reduction would be necessary to maintain stress at normal level according to our results and therapeutic approaches aimed directly at reducing stress should rather be sought after.

Colonic diverticular disease

Diverticula are outpouchings of the intestinal wall and are common anatomical alterations detected in the human colon. Colonic diverticulosis (the presence of diverticula in the colon; referred to as diverticulosis) remains asymptomatic in most individuals but ~25% of individuals will develop symptomatic diverticulosis, termed colonic diverticular disease (also known as diverticular disease). Diverticular disease can range in severity from symptomatic uncomplicated diverticular disease (SUDD) to symptomatic disease with complications such as acute diverticulitis or diverticular haemorrhage. Since the early 2000s, a greater understanding of the pathophysiology of diverticulosis and diverticular disease, which encompasses genetic alterations, chronic low-grade inflammation and gut dysbiosis, has led to improvements in diagnosis and management. Diagnosis of diverticular disease relies on imaging approaches, such as ultrasonography, CT and MRI, as biomarkers alone are insufficient to establish a diagnosis despite their role in determining disease severity and progression as well as in differential diagnosis. Treatments for diverticular disease include dietary fibre, pharmacological treatments such as antibiotics (rifaximin), anti-inflammatory drugs (mesalazine) and probiotics, alone or in combination, and eventually surgery. Despite being effective in treating primary disease, their effectiveness in primary and secondary prevention of complications is still uncertain.

A Brief Review of Nutraceutical Ingredients in Gastrointestinal Disorders: Evidence and Suggestions

The dietary effect on gut health has long been recognized through the empirical practice of soothing gastric discomfort with certain types of food, and recently the correlation between specific diets with lower incidences of several gastrointestinal diseases has been revealed. Ingredients from those considered beneficial foods have been isolated and studied, and some of them have already been put into the supplement market. In this review, we focus on latest studies of these food-derived ingredients for their proposed preventive and therapeutic roles in gastrointestinal disorders, with the attempt of drawing evidence-based suggestions on consuming these products.

Paradigm shift: the Copernican revolution in diverticular disease

Diverticular disease (DD) is an umbrella definition that includes different clinical conditions ranging from diverticulosis to severe and potentially life-threatening complications. In the last decade, new concepts regarding pathogenetic alterations have been developed, while the diagnostic, clinical and therapeutic approaches to the management of DD patients have changed. The protective role of dietary factors (i.e., fiber) has been questioned, whilst some drugs widely used in clinical practice have been found to have a deleterious effect. The use of antibiotics in all patients with acute uncomplicated diverticulitis was reconsidered, as well as the need for a surgical approach in these patients. Conflicting recommendations in different guidelines were proposed for the treatment of symptomatic uncomplicated DD. An endoscopic classification of DD was introduced, and a "curative" endoscopic approach has been pioneered. Based on these observations, which together amount to a kind of "Copernican revolution" in the management of DD patients, we performed a comprehensive and critical reappraisal of the proposed modifications, aiming to discriminate between certainties and doubts on this issue.

Role of dietary fibre in older adults with asymptomatic (AS) or symptomatic uncomplicated diverticular disease (SUDD): Systematic review and meta-analysis

Dietary fibre and probiotics may play a role in the management of diverticular disease. This systematic review synthesises the evidence on the effects of dietary fibre modifications, with or without the use of probiotics, on the incidence in older adults of asymptomatic (AS) or symptomatic uncomplicated diverticular disease (SUDD), as well as on gastrointestinal function and symptoms. Five electronic databases were searched for studies through to December 2018. The body of evidence was appraised using the Cochrane Risk of Bias tool and GRADE. Nine studies were included, with mean sample ages ranging from 57 to 70 years, and three meta-analyses were performed. Only one study, with high risk of bias, measured the effect of dietary fibre on the incidence of diverticulitis. Dietary fibre supplementation improved stool weight (MD: 42 g/day, P < 0.00001; GRADE level of evidence: low), but had no significant effect on gastrointestinal symptoms (SMD: -0.13, P = 0.16; GRADE level of evidence: low) or stool transit time (MD: -3.70, P = 0.32 GRADE level of evidence: low). There was "very low" confidence for the body of evidence supporting symbiotics for AS or SUDD. A high dietary fibre intake, in line with dietary guidelines, may improve gastrointestinal function and is recommended in patients with AS or SUDD. Dietary fibre supplementation should be considered on an individualised basis to improve bowel function, while any recommendation on symbiotic supplements requires further well-designed research. Future studies should also measure the impact on the incidence of diverticulitis.

Cyclic rifaximin therapy effectively prevents the recurrence of symptoms after exacerbation of symptomatic uncomplicated diverticular disease: a retrospective study

Introduction

Symptomatic uncomplicated diverticular disease (SUDD) is the most common manifestation of diverticulosis. Data concerning the optimal treatment after SUDD exacerbation are inconsistent.

Aim

To assess the effectiveness and necessity of cyclic rifaximin treatment for recurrent SUDD symptoms and for preventing exacerbations in patients who responded to the initial treatment.

Material and methods

A retrospective observational study was performed in 2017. Physicians responded to a survey on patients with recurrent SUDD during the observation period, who were cyclically treated with rifaximin 400 mg b.i.d. for 7 days per month. The patients’ SUDD history, diagnostic methods, treatment, and results were evaluated.

Results

In total 294 patients were included in this study (67% women, median age: 65 years (26–87)). The mean duration of diverticular disease (DD) was 4.5 years (1–20), and 88% had at least one repeated episode of SUDD exacerbation before rifaximin. A total of 267 patients were treated with rifaximin. Changes in the severity of pain, abdominal tenderness, diarrhoea, constipation, and bloating were assessed every 2 months. After 6 months of rifaximin treatment there was a statistically significant reduction in the total severity score (median from 1.8 (max. 3 points) to 0.2; p < 0.0001; sum from 9.37 (max. 18 points) to 1.35; p < 0.0001) and an improvement in individual symptom score.

Conclusions

Cyclical rifaximin is effective in treating exacerbation of SUDD. This regimen leads to a gradual cessation of symptoms over a 6-month period. In patients who responded to the initial treatment, cyclic rifaximin therapy is needed to maintain remission.

The Mexican consensus on the diagnosis and treatment of diverticular disease of the colon

Since the publication of the 2008 guidelines on the diagnosis and treatment of diverticular disease of the colon by the Asociación Mexicana de Gastroenterología, significant advances have been made in the knowledge of that disease. A systematic review of articles published in the medical literature from January 2008 to July 2018 was carried out to revise and update the 2008 guidelines and provide new evidence-based recommendations. All high-quality articles in Spanish and English published within that time frame were included. The final versions of the 43 statements accepted in the three rounds of voting, utilizing the Delphi method, were written, and the quality of evidence and strength of the recommendations were established for each statement, utilizing the GRADE system. The present consensus contains new data on the definition, classification, epidemiology, pathophysiology, and risk factors of diverticular disease of the colon. Special emphasis is given to the usefulness of computed tomography and colonoscopy, as well as to the endoscopic methods for controlling bleeding. Outpatient treatment of uncomplicated diverticulitis is discussed, as well as the role of rifaximin and mesalazine in the management of complicated acute diverticulitis. Both its minimally invasive alternatives and surgical options are described, stressing their indications, limitations, and contraindications. The new statements provide guidelines based on updated scientific evidence. Each statement is discussed, and its quality of evidence and the strength of the recommendation are presented.

Diet and the Role of Food in Common Gastrointestinal Diseases

Food plays an essential role in normal cellular processes; however, certain foods may also trigger or worsen certain disease states. This article focuses particularly on the role of food in common gastrointestinal and liver diseases, and discusses the current evidence that either supports or debunks common dietary recommendations. Nutrition topics discussed include the use of artificial sweetener for weight loss, avoidance of all dairy products in the setting of lactose intolerance, dietary recommendations for diverticular disease, and dietary management in cirrhotic patients with hepatic encephalopathy.

Treatment of diverticular disease, targeting symptoms or underlying mechanisms

Diverticular disease (DD) is a highly prevalent disease in western industrialized countries that encompasses a complex set of disorders. Because of its complexity and heterogeneity, both from a pathogenic and a clinical point of view, the management of this disease represent a challenge in clinical practice. This review aims to analyze and summarize the most recent evidence on the medical strategies for DD, considering separately the different stages of the disease, from prevention of diverticula formation to treatment of acute diverticulitis and prevention of recurrences. Based on some evidence, dietary fiber is useful to prevent diverticula formation and in diverticulosis, with no pharmacological treatment in these settings. Treatment of symptomatic uncomplicated diverticular disease as well as primary prevention of acute diverticulitis is based on probiotics, fibres, mesalazine and rifaximin, individually or as combination therapy, although a standard approach has not yet been defined. On the contrary, in acute diverticulitis (AD) recent acquisitions have clarified and standardized the role of systemic antibiotics, reserving its use only to complicated forms and in selected cases of uncomplicated disease. Secondary prevention of AD is essentially based on mesalazine and rifaximin but, despite promising results, no strong evidence have been produced. To date, grey areas remain in the medical management of DD.

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.

Emergency Presentations of Diverticulitis

Acute diverticulitis is a common condition that has been increasing in incidence in the United States. It is associated with increasing age, but the pathophysiology of acute diverticulitis is still being elucidated. It is now believed to have a significant contribution from inflammatory processes rather than being a strictly infectious process. There are still many questions to be answered regarding the optimal management of acute diverticulitis because recent studies have challenged traditional practices, such as the routine use of antibiotics, surgical technique, and dietary restrictions for prevention of recurrence.

Pathophysiology of diverticular disease

Inflammation of diverticula, or outpouchings of the colonic mucosa and submucosa through the muscularis layer, leads to diverticulitis. The development of diverticular disease, encompassing both diverticulosis and diverticulitis, is a result of genetic predisposition, lifestyle, and environmental factors, including the microbiome. Areas covered: Previous reports implicated genetic predisposition, environmental factors, and colonic dysmotility in diverticular disease. Recent studies have associated specific host immune responses and the microbiome as contributors to diverticulitis. To review pertinent literature describing pathophysiological factors associated with diverticulosis or diverticulitis, we searched the PubMed database (March 2018) for articles considering the role of colonic architecture, genetic predisposition, environment, colonic motility, immune response, and the microbiome. Expert commentary: In the recent years, research into the molecular underpinnings of diverticular disease has enhanced our understanding of diverticular disease pathogenesis. Although acute uncomplicated diverticulitis is treated with broad spectrum antibiotics, evaluation of the microbiome has been limited and requires further comprehensive studies. Evidence suggests that a deregulation of the host immune response is associated with both diverticulosis and diverticulitis. Further examining these pathways may reveal proteins that can be therapeutic targets or aid in identifying biological determinants of clinical or surgical decision making.

Management of colonic diverticular disease in the third millennium: Highlights from a symposium held during the United European Gastroenterology Week 2017

Diverticulosis is a common anatomical condition, which appears to be age-dependent. Individuals who develop chronic gastrointestinal symptoms or complications are referred to as having diverticular disease. Although the diagnosis of this condition can be relatively straightforward, randomized controlled trials are scarce and management often follows tradition rather than principles of evidence-based medicine. This report deals with the topics discussed during a symposium held during the United European Gastroenterology Week (Barcelona, October 2017). During the meeting, the role of dysbiosis in the pathogenesis of diverticular disease and its treatment were thoroughly discussed, by examining the efficacy and mechanisms of action of the currently used drugs. Recent studies have shown the presence of dysbiosis in patients with diverticular disease and suggest an imbalance in favor of bacteria with pro-inflammatory and pathogenetic potential. These microbiota changes correlate with mucosal immune activation, mirrored by a marked increase of macrophages in colonic mucosa, both in the diverticular region and at distant sites. The low-grade inflammation, driven by bacteria-induced immune activation, could be involved in the pathophysiology of symptoms. As a consequence, pharmacological approaches targeting enteric bacteria (with poorly absorbed antibiotics, like rifaximin, or probiotics) or intestinal inflammation (with 5-ASA derivatives or rifaximin) have shown capability of controlling symptoms and also preventing complications, albeit more research is needed to establish the optimal regimen (daily dose and duration) of therapy. Well-designed randomized-controlled trials (RCTs), including homogeneous populations of patients, are therefore needed. The future of management of many GI diseases, including symptomatic uncomplicated diverticular disease, will rely on the so-called 'microbiota-directed therapies'.

Evidence for Dietary Fibre Modification in the Recovery and Prevention of Reoccurrence of Acute, Uncomplicated Diverticulitis: A Systematic Literature Review

In practice, nutrition recommendations vary widely for inpatient and discharge management of acute, uncomplicated diverticulitis. This systematic review aims to review the evidence and develop recommendations for dietary fibre modifications, either alone or alongside probiotics or antibiotics, versus any comparator in adults in any setting with or recently recovered from acute, uncomplicated diverticulitis. Intervention and observational studies in any language were located using four databases until March 2017. The Cochrane Risk of Bias tool and GRADE were used to evaluate the overall quality of the evidence and to develop recommendations. Eight studies were included. There was "very low" quality evidence for comparing a liberalised and restricted fibre diet for inpatient management to improve hospital length of stay, recovery, gastrointestinal symptoms and reoccurrence. There was "very low" quality of evidence for using a high dietary fibre diet as opposed to a standard or low dietary fibre diet following resolution of an acute episode, to improve reoccurrence and gastrointestinal symptoms. The results of this systematic review and GRADE assessment conditionally recommend the use of liberalised diets as opposed to dietary restrictions for adults with acute, uncomplicated diverticulitis. It also strongly recommends a high dietary fibre diet aligning with dietary guidelines, with or without dietary fibre supplementation, after the acute episode has resolved.

Treatment of diverticular disease: an update on latest evidence and clinical implications

BACKGROUND

Diverticular disease (DD) is a common condition, especially in Western countries. In about 80% of patients, colonic diverticula remain asymptomatic (diverticulosis), while approximately 20% of patients may develop abdominal symptoms (symptomatic uncomplicated diverticular disease, SUDD) and, eventually complications as acute diverticulitis (AD). The management of this condition has been improved, and in the last five years European countries and the USA have published guidelines and recommendations.

SCOPE

To summarize the latest evidence and clinical implication in treatment of DD focusing the attention either on the treatment of diverticulosis, SUDD and AD together with the primary and secondary prevention of diverticulitis.

FINDINGS

The present review was based on the latest evidence in the treatment of DD in the last 10 years. In the last 5 years, six countries issued guidelines on DD with differences regarding covered topics and recommendations regarding treatments. At present there is a lack of rationale for drug use in patients with asymptomatic diverticulosis, but there are limited indications to suggest an increase in dietary fibre to reduce risk of DD. To achieve symptomatic relief in SUDD patients, several therapeutic strategies with fibre, probiotics, rifaximin and mesalazine have been proposed even if a standard therapeutic approach remained to be defined. Agreement has been reached for the management of AD, since recent guidelines showed that antibiotics can be used selectively, rather than routinely in uncomplicated AD, although use of antibiotics remained crucial in the management of complicated cases. With regard to treatment for the primary and secondary prevention of AD, the efficacy of rifaximin and mesalazine has been proposed although with discordant recommendations among guidelines.

CONCLUSION

Treatment of DD represented an important challenge in clinical practice, especially concerning management of SUDD and the primary and secondary prevention of AD.