Recurrence Of Acute Diverticulitis Research Articles

Acute diverticulitis: beyond the diagnosis: predictive role of CT in assessing risk of recurrence and clinical implications in non-operative management of acute diverticulitis

PurposeThe aim of the study is to identify CT findings that are predictive of recurrence of acute uncomplicated colonic diverticulitis, to better risk-stratify these patients for whom guidelines recommend a conservative outpatient treatment and to determine the appropriate management with an improvement of health costs.Materials and MethodsOver the past year, 33 patients enrolled in an outpatient integrated care pathway (PDTA) for uncomplicated acute diverticulitis with 1-year follow-up period, without recurrence, and 33 patients referred to Emergency Department for a recurrent acute diverticulitis were included. Images of admission CT were reviewed by two radiologists and the imaging features were analyzed and compared with Chi-square and Student t tests. Univariate and multivariate Cox regression models were employed to identify parameters that significantly predicted recurrence in 1-year follow-up period and establish cutoff and recurrence-free rates. The maximally selected rank statistics (MSRS) were used to identify the optimal wall thickening cutoff for the prediction of recurrence.ResultsPatients with recurrence showed a greater mean parietal thickness compared to the group without recurrence (16 mm vs. 11.5 mm; HR 1.25, p < 0.001) and more evidence of grade 4 of peridiverticular inflammation (40% vs. 12%, p = 0.009, HR 3.44). 12-month recurrence-free rates progressively decrease with increasing thickness and inflammation. In multivariate analysis, only parietal thickness maintained its predictive power with an optimal cutpoint > 15 mm that causes a sixfold increased risk of recurrence (HR 6.22; 95% CI, 3.05–12.67; p < 0.001). Beyond thickness and peridiverticular inflammation, predictive value of early recurrence within 90 days from the 1st episode resulted also an Hinchey Ib on admission CT.ConclusionsThe maximum wall thickening and the grade of peridiverticular inflammation can be considered as predictive factors of recurrence and may be helpful in selecting patients for a tailored treatment to prevent the risk of recurrence.

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

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. To review the current knowledge and discuss the unmet needs regarding the management of SUDD and the prevention of acute diverticulitis. 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. 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. Information on patient population, study design, intervention, control group, duration of the observation, and outcomes assessed was collected by two authors independently. 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. 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 Association Between Solid Organ Transplant and Recurrence of Acute Diverticulitis: A National Assessment.

The aim of this study was to compare rates and severity of recurrent acute diverticulitis in patients with and without solid organ transplant. Immunocompromised solid organ transplant recipients have been considered higher risk for both recurrence and severity of acute diverticulitis. Current guidelines recommend an individualized approach for colectomy in these patients, but these are based on single-center data. We identified patients with acute diverticulitis using the Merative MarketScan commercial claims data from 2014 to 2020. Patients were classified by history of solid organ transplant. The primary outcome was recurrence of acute diverticulitis with an associated antibiotic prescription ≥60 days from the initial episode. Secondary outcomes included hospitalization, colectomy, and ostomy in patients with recurrence. Analyses used inverse probability weighting to adjust for imbalances in covariates. Of 170,697 patients with evidence of acute diverticulitis, 442 (0.2%) had a history of solid organ transplantation. In the weighted cohort, among people who had not been censored at 1 year (n=515), 112 (22%; 95% CI: 20%-25%) experienced a recurrence within the first year. Solid organ transplantation was not significantly associated with a risk of recurrence (hazard ratio=1.19; 95% CI: 0.94-1.50). There was also no statistically significant difference in the hospitalization rate for recurrent diverticulitis. Restricting the analysis to hospitalized recurrences, there was no statistically significant difference observed in either length of stay or discharge status. In this national analysis of commercially insured patients with acute diverticulitis we found no statistically significant differences in recurrence between those with and without a history of solid organ transplant. We do not support an aggressive colectomy strategy based on concern for increased recurrence rate and severity in a solid organ transplant population.

Risk factors for readmission in patients with acute diverticulitis: a retrospective study at Auckland City Hospital.

Approximately one in five patients with acute diverticulitis (AD) will experience a recurrence. This study aimed to investigate the factors at AD admission that correlate with recurrence and test the proposed risk of recurrence-score according to Sallinen et al. method: This retrospective study followed patients for five years who were admitted with operatively or computed tomography (CT)-verified AD at Auckland City Hospital from January 2012-June 2013. Demographic, laboratory, radiological and patient-related factors at initial admission were analysed in relation to readmission with recurrent AD and to test a risk score presented by Sallinen et al. results: In the adjusted analyses, previous diagnosis of AD (OR, 7.3; 95% CI, 3.1-16.9), Māori ethnicity (OR, 5.7; 95% CI, 1.4-22.7) and complicated AD at index admission (OR, 2.5; 95% CI, 1.0-6.2), were all independent factors associated with readmission with recurrence. High-risk versus low-risk groups, according to the risk score, showed 71.4% and 18.6% recurrence rates, respectively. History of diverticulitis and complicated AD are risk factors for recurrence. The finding of higher recurrence rate in Māori requires further investigation utilising appropriate research methodologies. The risk score presented by Sallinen et al. may be a useful predictor of recurrent AD.

A Rare Presentation of Recurrent Diverticulitis in a Patient with Ulcerative Colitis.

Diverticulitis and ulcerative colitis (UC) are two separate colonic pathologies with different underlying mechanisms. Diverticulosis involves herniation of mucosal and submucosal tissue through muscular tissue in response to increased intraluminal pressure. In contrast, it is believed that the muscular tone in patients with UC is reduced due to chronic inflammatory changes. Thus, it has been reported that there may be an inverse relationship between the presence of diverticulosis in patients with UC, in that UC may possibly be protective against developing diverticular disease. Consequently, the co-presence of both pathologies is uncommon. Here we present a case in which a woman with a history of UC and recurrent diverticulitis after elective partial colectomy was admitted for recurrent acute diverticulitis. It is quite challenging to diagnose diverticulitis in ulcerative colitis patients given the usually similar presentation with abdominal pain, diarrhoea and hematochezia. A level of high suspicion is required for diagnosis.LEARNING POINTSColonic diverticulitis is not commonly associated with ulcerative colitis.The diagnosis of colonic diverticulitis in the setting of ulcerative colitis is challenging and requires a high level of suspicion.

The Impact of Bariatric Surgery on Diverticulitis Outcomes and Risk of Recurrent Hospitalizations in Adults with Clinically Severe Obesity.

Clinically severe obesity (SO) is a known risk factor for worsened outcomes and recurrence of acute diverticulitis. Paucity of data exist on outcomes of diverticulitis after bariatric surgery. The Nationwide Readmissions Database was queried for diverticulitis hospitalizations between the years 2010 and 2014. We restricted analysis to patients with SO and those who had bariatric surgery (BRS). Outcomes of mortality, surgical events, and recurrent diverticulitis admissions were compared using multivariable analysis and one-to-one propensity score matching. Among 52,274 diverticulitis admissions, 91.2% (47,694) patients had SO and 8.8% (4580) had prior BRS. Patients with SO had higher odds of suffering mortality on index diverticulitis admission when compared to those with prior BRS [adjusted odds ratio (aOR): 10.55; 95%CI 1.45,76.75]. Patients with SO were also more likely to undergo emergency surgery (aOR: 1.71; 95%CI 1.25,2.34) and colectomy (aOR: 1.45; 95%CI 1.26,1.68). Rates of recurrent diverticulitis readmissions within 30days and 6months were also higher in patients with SO compared to BRS patients (aOR: 7.94; 95%CI 1.09,57.83 and aOR: 1.98; 95%CI 1.14,3.43, respectively). Propensity score matching confirmed our findings of increased rates of mortality (OR: 17.28; 95%CI 2.02,147.6), recurrent diverticulitis, and worsened surgical outcomes within 30days in patients with SO compared to BRS. This study is first to show improved outcomes and less recurrent hospitalizations for diverticulitis after bariatric surgery compared to patients with clinically severe obesity. Further studies are needed to understand mechanisms leading to this improvement and the role of weight loss in prevention of severe diverticulitis.

S3508 Chronic Diverticulitis Due to Recurrent Acute Diverticulitis Treated With Surgery

S3508 Chronic Diverticulitis Due to Recurrent Acute Diverticulitis Treated With Surgery

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.

Optimizing medical management for diverticular disease: A systematic review and gap analysis

BackgroundResolution of acute diverticulitis is often associated with ongoing gastrointestinal symptoms and risk for recurrent episodes. Surgical guidelines recommend individualized treatment options but medical management strategies have been inconsistently implemented in surgical practice. This study reviews the evidence for medical management to reduce episodes or decrease gastrointestinal symptoms to inform shared decision-making discussions with patients and identifies key evidence gaps for the medical management of diverticular disease. MethodsPubMed, Embase, and the Cochrane Central Register of Controlled Trials were systematically searched to identify randomized clinical trials on recurrent acute diverticulitis and symptomatic uncomplicated diverticular disease that studied medical treatment strategies including fiber supplementation, probiotics, mesalamine, and rifaximin. Two independent researchers screened references and assessed articles for eligibility. Outcomes of interest included patient-reported symptom improvement and diverticulitis recurrence. Results27 of 485 unique articles identified in the electronic research met eligibility for inclusion. Three focused on fiber, three on probiotics, twelve on mesalamine, and nine on rifaximin with conflicting results. ConclusionMedical management options are available and may be helpful in some patients following resolution of acute diverticulitis to improve symptom burden and recurrent episodes of diverticulitis. Further investigation is needed to inform which subpopulation of patients are likely to benefit from different treatment strategies.

Systematic review of failure of nonoperative management in complicated sigmoid diverticulitis with abscess.

The aim of this systematic review was to determine the rates of failure following nonoperative management for acute sigmoid diverticulitis complicated by abscess. Pubmed and Medline were systematically searched by two independent researchers. Studies reporting outcomes of nonoperative management of diverticulitis with abscess revealed on CT scan were included. The endpoint of the study was failure of nonoperative management which included relapse and recurrence. Relapse was defined as development of additional complications such as peritonitis or obstruction that required urgent surgery during index admission or readmission within 30days. Recurrence was defined as development of symptoms after an asymptomatic period of 30-90days following nonoperative management. Nonoperative management included nil per os, intravenous fluids and antibiotics, CT-guided percutaneous drainage, and/or total parenteral nutrition. Twenty-four of 844 studies yielded by literature search totaling 12,601 patients were eligible for inclusion. Pooled relapse rate was 18.9%. The pooled rate of recurrence of acute diverticulitis was found to be 25.5%. 60.9% of recurrences were complicated diverticulitis. Failure rate appeared to be significantly increased in patients undergoing percutaneous drainage for distant abscess as compared with pericolic abscess (51% vs. 18%; p = 0.0001). The rate of failure of nonoperative management was 44.4%. The rate of relapse at 30days following nonoperative management was at 18.9%. Distant abscesses were associated with significantly increased rates of relapse compared with pericolic abscesses. The rate of recurrence following nonoperative management was 25.5% at themean follow-up of 38months.

Influence of obesity on the risk of recurrent acute diverticulitis.

Acute diverticulitis (AD) is a common surgical problem with increasing incidence. Obesity has become epidemic in western countries. Obesity has been shown to increase the risk of developing AD; however, little is known about its influence on the risk of recurrence. The decision to perform elective surgical resection to reduce the risk of recurrent AD is made on an individual basis considering perceived risk of recurrence weighed against patient comorbidity. The aim of this study is to assess whether obesity affects the likelihood of developing recurrent AD. A retrospective audit was conducted of all admissions with AD to a tertiary centre between 1998 and 2010. Medical records were reviewed and patients with an index presentation with AD included in the analysis. Imaging was used to calculate body mass index (BMI) for assessment of obesity. Follow-up was for a minimum of 3 years from admission. A total of 1299 patients were admitted with an index presentation of AD in the study period. 18.3% overall had recurrent AD, all of whom had confirmation on imaging. Computed tomography was used to calculate BMI in 849 patients, of whom 470 (55.4%) were considered obese (BMI >30). The likelihood of recurrent AD was not significantly different in obese patients compared to their non-obese counterparts (P = 0.2473). While obesity increases the risk of developing AD overall, it does not appear to increase the likelihood of developing recurrent AD. This has implications for risk stratification when considering surgical resection to prevent recurrent AD.

Course of the Diverticular Disease: What is changing?

In this session several critical issues in diverticular disease were considered, including "It is Symptomatic Diverticular Disease or Irritable Bowel Syndrome?", "What do determine evolution to diverticulitis, bowel habits alteration or inflammation?", and "Prevention of acute diverticulitis: Is it at all possible?". The first talking compared symptoms and laboratory findings between Symptomatic Uncomplicated Diverticular Disease (SUDD) and Irritable Bowel Syndrome (IBS). Although both disease share some symptoms, and although IBS can occur in patients having diverticulosis, SUDD and IBS can be differentiate using a combination of symptoms and laboratory tools. The second talking debated what are the most important risk factors for the evolution towards acute diverticulitis. Current data seem to exclude a significant role of bowel habits alteration, while inflammation seems to have a stronger role, especially in causing acute diverticulitis recurrence. The third talking analyzed about the acute diverticulitis prevention. Primary prevention seem to be little better when using mesalazine, while no definite conclusion can be drawn about the use of fiber and rifaximin. About the secondary prevention, no drugs can be currently advised due to lacking of definite results. At the same time, surgery should be advised on case-by-case basis.

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.

A Worldwide Perspective on Diagnosis and Management of Diverticular Disease: Understanding Similarities and Differences

The epidemiology of diverticular disease (DD) is changing, with an increasing prevalence in younger patients from Europe and the USA, and changing disease patterns also seen in Asian populations. This epidemiological shift has substantial implications for disease management policy and healthcare costs. Most (75–80%) patients with diverticulosis never develop symptoms. Around 5% develop acute diverticulitis or other complications, while 10–15% develop symptomatic uncomplicated DD (SUDD) with symptoms resembling irritable bowel syndrome (IBS). However, most available guidelines highlight the importance of diverticulitis, with less emphasis on and often limited discussion about SUDD and its management. Recent data suggest an important relationship between gut microbiota and DD, including SUDD. In healthy individuals, the gut microbiota exists in harmony (eubiosis); in individuals with disease, quantitative and qualitative changes in microbial diversity (dysbiosis) may adversely influence colonic metabolism and homeostasis. Addressing this imbalance and restoring a healthier microbiota via eubiotic or probiotic therapy may be of value. In SUDD, clinical benefit has been seen with the use of rifaximin, which acts by multiple mechanisms: direct antibiotic activity, a modulatory eubiotic effect with an increase in muco-protective Lactobacillus and Bifidobacterium organisms, and anti-inflammatory effects, among others. Clinical studies have demonstrated symptom improvement and reduction in complications in patients with SUDD, with a favourable safety and tolerability profile and no evidence of microbial resistance. Evidence for other agents in DD is less robust. Mesalamine is not effective at preventing recurrence of acute diverticulitis, although it may provide some symptom improvement. At present, there is insufficient evidence to recommend the use of probiotics in SUDD symptom management.

Risk of Recurrent Disease and Surgery Following an Admission for Acute Diverticulitis.

Diverticular disease accounts for significant morbidity and mortality and may take the form of recurrent episodes of acute diverticulitis. The role of elective surgery is not clearly defined. This study aimed to define the rate of hospital admission for recurrent acute diverticulitis and risk factors associated with recurrence and surgery. This is a retrospective population-based cohort study. National Health Service hospital admissions for acute diverticulitis in England between April 2006 and March 2011 were reviewed. Hospital Episode Statistics data identified adult patients with the first episode of acute diverticulitis (index admission), and then identified recurrent admissions and elective or emergency surgery for acute diverticulitis during a minimum follow-up period of 4 years. Exclusion criteria included previous diagnoses of acute diverticulitis, colorectal cancer, or GI bleeding, and prior colectomy or surgery or death during the index admission. There were no interventions. The primary outcomes measured were recurrent admissions for acute diverticulitis and patients requiring either elective or emergency surgery during the study period. Some 65,162 patients were identified with the first episode of acute diverticulitis. The rate of hospital admission for recurrent acute diverticulitis was 11.2%. A logistic regression model examined factors associated with recurrent acute diverticulitis and surgery: patient age, female sex, smoking, obesity, comorbidity score >20, dyslipidemia, and complicated acute diverticulitis increased the risk of recurrent acute diverticulitis. There was an inverse relationship between patient age and recurrence. Similar factors were associated with elective and emergency surgery. The cases of acute diverticulitis required inpatient management and the use of Hospital Episode Statistics, relying on the accuracy of diagnostic coding. This is the largest study assessing the rates of hospital admission for recurrent acute diverticulitis. Knowledge of the rate and risk factors for recurrent acute diverticulitis is required to aid discussion and decision making with patients regarding the need and timing of elective surgery. Some factors associated with recurrence are modifiable; therefore, weight reduction and smoking cessation can be championed. See Video Abstract at http://links.lww.com/DCR/A449.

Progress and challenges in the management of diverticular disease: which treatment?

Diverticular disease of the colon (DDC) includes a spectrum of conditions from asymptomatic diverticulosis to symptomatic uncomplicated diverticulosis, segmental colitis associated with diverticulosis, and acute diverticulitis without or with complications that may have serious consequences. Clinical and scientific interest in DDC is increasing because of the rising incidence of all conditions within the DDC spectrum, a better, although still limited understanding of the pathogenic mechanisms involved; the increasing socioeconomic burden; and the new therapeutic options being tested. The goals of treatment in DDC are symptom and inflammation relief and preventing disease progression or recurrence. The basis for preventing disease progression remains a high-fiber diet and physical exercise, although evidence is poor. Other current strategies do not meet expectations or lack a solid mechanistic foundation; these strategies include modulation of gut microbiota or dysbiosis with rifaximin or probiotics, or using mesalazine for low-grade inflammation in uncomplicated symptomatic diverticulosis. Most acute diverticulitis is uncomplicated, and the trend is to avoid hospitalization and unnecessary antibiotic therapy, but patients with comorbidities, sepsis, or immunodeficiency should receive broad spectrum and appropriate antibiotics. Complicated acute diverticulitis may require interventional radiology or surgery, although the best surgical approach (open versus laparoscopic) remains a matter of discussion. Prevention of acute diverticulitis recurrence remains undefined, as do therapeutic strategies. Mesalazine with or without probiotics has failed to prevent diverticulitis recurrence, whereas new studies are needed to validate preliminary positive results with rifaximin. Surgery is another option, but the number of acute events cannot guide this indication. We need to identify risk factors and disease progression or recurrence mechanisms to implement appropriate preventive strategies.

Management of diverticulosis: what's new?

The incidence of diverticulosis and diverticular disease (DD) of the colon, including acute diverticulitis, is increasing worldwide, and becoming a significant burden on national health systems in terms of direct and indirect costs. Thus, significant efforts are now being focused to identify the correct therapeutic approach to treat symptomatic patients and to prevent diverticulitis. Fiber, non-absorbable antibiotics, 5-aminosalicylic acid and probioticsare currently being investigated in this way. Unfortunately, current evidences on the effectiveness of some medical treatment in preventing acute diverticulitis recurrence are still lacking. The effectiveness and the future perspectives of these treatments are discussed herein.

DIVERTICULAR DISEASE OF THE COLON: RESOLVED AND UNRESOLVED ISSUES

The article is devoted to the classification and treatment of diverticular disease of the colon, which is by its prevalence, nature, clinical manifestations, complications is not only a medical but also a huge socio-economic problem. The article elaborates various domestic and foreign classification approaches with the reflection of the merits and costs requiring appropriate changes in the modern Russian guidelines for the diagnosis and treatment of adult patients with diverticular disease of the colon for the development of treatment and preventive measures in different forms of the disease. The place and the analysis of the effectiveness of different therapy regimens with the use of the effect of rifaximin-α (Alfa Normix), mesalazine, dietary fiber, particularly psyllium in the treatment of diverticular disease without clinical manifestations (asymptomatic diverticulosis); DB with clinical manifestations, including recurrent form (symptomatic uncomplicated diverticulosis); in the treatment of acute uncomplicated diverticulitis and for prevention of recurrence of acute diverticulitis (term and permanent treatment) are established.

Management of acute uncomplicated diverticulitis without antibiotics: a single-centre cohort study.

This study aimed to evaluate the implementation of nonantibiotic management of acute uncomplicated diverticulitis at a large university hospital in Norway with regard to management failure, disease recurrence and complications. On 1 January 2013 we implemented a new policy for the management of acute uncomplicated diverticulitis without antibiotics. Antibiotic treatment was only provided in the case of defined criteria. All patients admitted from 1 January 2013 to 30 June 2014 with a CT-verified, left-sided, acute uncomplicated diverticulitis were included in the study and evaluated retrospectively, with 12months' follow-up. Of 244 admissions with acute uncomplicated diverticulitis, 177 (73%) were managed without antibiotics. Among these there were seven (4%) management failures, including five patients in whom a deteriorating clinical picture prompted antibiotic treatment and two readmissions within 1month due to persisting symptoms. The only complication in this group was one fistula (<1%). Eight (5%) patients had a recurrence of acute diverticulitis requiring hospital care and two (1%) underwent elective surgery within the first year. Twenty (8%) patients met predefined exemption criteria and received antibiotics from admission, six (30%) of whom developed complications. The recurrence rate in this group was 10% and none had surgery performed. The 47 (20%) policy violators treated with antibiotics from admission had no complications. Their recurrence rate was 11% and one (2%) patient underwent elective surgery. This study confirms that nonantibiotic management of acute uncomplicated diverticulitis is safe and feasible. Most complications occurred in a small group of high-risk patients treated with antibiotics.

Diverticulosis today: unfashionable and still under-researched.

Diverticulosis of the colon is a widespread disease, and its prevalence is increasing especially in the developing world. The underlying pathological mechanisms that cause the formation of colonic diverticula remain unclear but are likely to be the result of complex interactions among age, diet, genetic factors, colonic motility, and changes in colonic structure. The large majority of patients remain asymptomatic throughout their life, one fifth of them become symptomatic (developing the so-called 'diverticular disease') while only a minority of these will develop acute diverticulitis. The factors predicting the development of symptoms remain to be identified. Again, it is generally recognized that diverticular disease occurrence is probably related to complex interactions among colonic motility, diet, lifestyle, and genetic features. Changes in intestinal microflora due to low-fiber diet and consequent low-grade inflammation are thought to be one of the mechanisms responsible for symptoms occurrence of both diverticular disease and acute diverticulitis. Current therapeutic approaches with rifaximin and mesalazine to treat the symptoms seem to be promising. Antibiotic treatment is currently advised only in acute complicated diverticulitis, and no treatment has currently proven effective in preventing the recurrence of acute diverticulitis. Further studies are required in order to clarify the reasons why diverticulosis occurs and the factors triggering occurrence of symptoms. Moreover, the reasons why rifaximin and mesalazine work in symptomatic diverticular disease but not in acute diverticulitis are yet to be elucidated.