Pathogenesis of colonic diverticula

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.

Impact of Oral Probiotics in Amelioration of Immunological and Inflammatory Responses on Experimentally Induced Acute Diverticulitis

Acute diverticulitis is inflammation of a colon diverticulum; it represents a major cause of morbidity and mortality. The alteration of gut microbiota contributes to the promotion of inflammation and the development of acute diverticulitis disease. Probiotics can modify the gut microbiota, so they are considered a promising option for managing diverticulitis disease. This study aimed to investigate the potential protective effect of probiotics, alone or in combination with amoxicillin, on the experimentally induced model of acute diverticulitis disease. Forty-two rats were divided into seven groups as follows: control group: received water and food only; DSS group: received 3% dextran sulfate sodium (DSS) daily for 7 days; LPS group: injected with lipopolysaccharide (LPS) enema at the dose of (4 mg/kg); probiotics group: treated with probiotics (Lactobacillus acidophilus and Bifidobacterium lactis) each of which (4 × 108 CFU suspended in 2 ml distilled water) orally for 7 days; DSS/LPS group: received DSS and LPS; DSS/LPS treated with probiotics group; DSS/LPS treated with probiotics and amoxicillin group. The results revealed that both treatments (probiotics and probiotics-amoxicillin) attenuated DSS/LPS-induced diverticulitis, by restoring the colonic antioxidant status, ameliorating inflammation (significantly reduced TNF-α, interleukins, interferon-γ, myeloperoxidase activity, and C-reactive protein), decreasing apoptosis (through downregulating caspase-3), and reduction of the colon aerobic bacterial count. These probiotic strains were effective in preventing the development of the experimentally induced acute diverticulitis through the anti-inflammatory and immunomodulatory effects and have affected gut microbiota, so they can be considered a potential option in treating acute diverticulitis disease.

Utility of monocyte distribution width in the differential diagnosis between simple and complicated diverticulitis: a retrospective cohort study

BACKGROUND

Colonic diverticulitis is a leading cause of abdominal pain. The monocyte distribution width (MDW) is a novel inflammatory biomarker with prognostic significance for coronavirus disease and pancreatitis; however, no study has assessed its correlation with the severity of colonic diverticulitis.

METHODS

This single-center retrospective cohort study included patients older than 18 years who presented to the emergency department between November 1, 2020, and May 31, 2021, and received a diagnosis of acute colonic diverticulitis after abdominal computed tomography. The characteristics and laboratory parameters of patients with simple versus complicated diverticulitis were compared. The significance of categorical data was assessed using the chi-square or Fisher's exact test. The Mann-Whitney U test was used for continuous variables. Multivariable regression analysis was performed to identify predictors of complicated colonic diverticulitis. Receiver operator characteristic (ROC) curves were used to test the efficacy of inflammatory biomarkers in distinguishing simple from complicated cases.

RESULTS

Of the 160 patients enrolled, 21 (13.125%) had complicated diverticulitis. Although right-sided was more prevalent than left-sided colonic diverticulitis (70% versus 30%), complicated diverticulitis was more common in those with left-sided colonic diverticulitis (61.905%, p = 0.001). Age, white blood cell (WBC) count, neutrophil count, C-reactive protein (CRP) level, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and MDW were significantly higher in the complicated diverticulitis group (p < 0.05). Logistic regression analysis indicated that the left-sided location and the MDW were significant and independent predictors of complicated diverticulitis. The area under the ROC curve (AUC) was as follows: MDW, 0.870 (95% confidence interval [CI], 0.784-0.956); CRP, 0.800 (95% CI, 0.707-0.892); NLR, 0.724 (95% CI, 0.616-0.832); PLR, 0.662 (95% CI, 0.525-0.798); and WBC, 0.679 (95% CI, 0.563-0.795). When the MDW cutoff was 20.38, the sensitivity and specificity were maximized to 90.5% and 80.6%, respectively.

CONCLUSIONS

A large MDW was a significant and independent predictor of complicated diverticulitis. The optimal cutoff value for MDW is 20.38 as it exhibits maximum sensitivity and specificity for distinguishing between simple and complicated diverticulitis The MDW may aid in planning antibiotic therapy for patients with colonic diverticulitis in the emergency department.

Cardiovascular Risk Factors and Physical Fitness Among Subjects with Asymptomatic Colonic Diverticulosis

BACKGROUND

The association between diverticular disease and atherosclerotic cardiovascular disease (ASCVD) has been demonstrated previously, mainly in symptomatic subjects.

AIMS

To evaluate 10 years cardiovascular risk, exercise performance and association to ASCVD among subjects with asymptomatic diverticulosis.

METHODS

A retrospective cross-sectional cohort of self-referred participants in a medical screening program, who underwent a screening colonoscopy. Demographics, clinical and laboratory variables, ASCVD score, and metabolic equivalents (METs) during treadmill stress test were compared between subjects with and without diverticulosis as diagnosed on screening colonoscopy.

RESULTS

4586 participants underwent screening colonoscopy; 799 (17.4%) had diverticulosis. Among 50-69 yo participants, diverticulosis subjects had a higher ASCVD score compared to non-diverticulosis subjects. Exercise performance was comparable between the groups, across all age groups. Using logistic regression analysis, advanced age group (50-59 yo Adjusted odds ratio (AOR) [95% confidence interval (CI)] 2.57 (1.52-4.34), p < 0.001; 60-69 yo, AOR 2.87 (2.09-3.95), p < 0.001; ≥ 70 yo AOR 4.81 (3.23-7.15), p < 0.001; compared to < 50 yo age group), smoking [AOR 1.27 (1.05-1.55), p = 0.016], HTN [AOR 1.27 (1.03-1.56), p = 0.022], obesity [AOR 1.36 (1.06-1.74), p = 0.014] and male sex [AOR 1.29 (1.02-1.64), p = 0.036] were associated with diverticular detection during screening colonoscopy. Among males, achieving METs score ≥ 10 was inversely associated with diverticular detection during screening colonoscopy [AOR 0.64 (0.43-0.95), p = 0.027].

CONCLUSIONS

Ten years probability for ASCVD estimated by the ASCVD score is higher among subjects with asymptomatic diverticulosis compared to subjects without diverticulosis. Improved exercise performance is demonstrated for the first time to correlate with decreased probability for diverticular disease in screening colonoscopy.

[Diagnosis and Treatment of Colonic Diverticular Disease]

Colonic diverticulosis is one of the most common conditions of the digestive system and patients generally remain asymptomatic. However, about 20% of patients develop symptomatic diverticular disease such as acute diverticulitis or diverticular hemorrhage, and these have become a huge burden on healthcare systems worldwide. Recent understanding of the pathophysiology of diverticulosis and diverticular disease suggests the role of multiple factors including genetic and environment. Based on this understanding, a preventive strategy to reduce the risk factors of diverticulosis and diverticular disease is highly recommended. The diagnosis of the acute diverticulitis relies on imaging modalities such as an abdominal-pelvic CT scan together with symptoms and signs. Treatment of diverticular disease should be individualized and include modification of lifestyle, use of antibiotics, and surgery. Recent guidelines recommend pursuing less aggressive treatment for patients with acute diverticulitis. This review will provide an overview of both the existing and evolving understanding regarding colonic diverticulosis and diverticular disease and can help clinicians in the management of their patients with diverticular disease.

Age, alcohol, sex, and metabolic factors as risk factors for colonic diverticulosis

BACKGROUND

The pathogenesis of colonic diverticulosis is not well understood. Moreover, only a few studies on colonic diverticulosis have been reported in mainland China.

AIM

To evaluate the prevalence of and risk factors for asymptomatic colorectal diverticulosis in Eastern China.

METHODS

From August 2016 to July 2020, 6180 asymptomatic individuals were enrolled in this cross-sectional study. These individuals had undergone physical examinations, laboratory testing, and colonoscopy. Data regarding the baseline characteristics and their general health status were obtained through interviews.

RESULTS

The prevalence of colonic diverticulosis was 7.3% (449/6180). Colonic diverticulosis was detected predominantly on the right side of the colon (88.4%). Logistic regression analysis revealed that an age ≥ 60 years (adjusted odds ratio [OR] 2.149, 95% confidence interval [CI] 1.511-3.057, P < 0.001), male sex (adjusted OR: 1.878, 95%CI: 1.373-2.568, P < 0.001), obesity (adjusted OR: 1.446, 95%CI: 1.100-1.902, P = 0.008), alcohol intake (adjusted OR: 1.518, 95%CI: 1.213-1.901, P < 0.001), hypertension (adjusted OR: 1.454, 95%CI: 1.181-1.789, P < 0.001), hypertriglyceridemia (adjusted OR: 1.287, 95%CI: 1.032-1.607, P = 0.025), and hyperuricemia (adjusted OR: 1.570, 95%CI: 1.257-1.961, P < 0.001) significantly increased the risk of colonic diverticulosis.

CONCLUSION

Advanced age, male sex, alcohol intake, obesity, and other metabolic-related factors, such as hypertension, hypertriglyceridemia, and hyperuricemia, were independent risk factors for colonic diverticulosis. Understanding the true prevalence of colonic diverticulosis and its associated risk factors will aid in its prevention and treatment.

The Association of Coloproctology of Great Britain and Ireland consensus guidelines in emergency colorectal surgery

AIM

There is a requirement for an expansive and up to date review of the management of emergency colorectal conditions seen in adults. The primary objective is to provide detailed evidence-based guidelines for the target audience of general and colorectal surgeons who are responsible for an adult population and who practise in Great Britain and Ireland.

METHODS

Surgeons who are elected members of the Association of Coloproctology of Great Britain and Ireland Emergency Surgery Subcommittee were invited to contribute various sections to the guidelines. They were directed to produce a pathology-based document using literature searches that were systematic, comprehensible, transparent and reproducible. Levels of evidence were graded. Each author was asked to provide a set of recommendations which were evidence-based and unambiguous. These recommendations were submitted to the whole guideline group and scored. They were then refined and submitted to a second vote. Only those that achieved >80% consensus at level 5 (strongly agree) or level 4 (agree) after two votes were included in the guidelines.

RESULTS

All aspects of care (excluding abdominal trauma) for emergency colorectal conditions have been included along with 122 recommendations for management.

CONCLUSION

These guidelines provide an up to date and evidence-based summary of the current surgical knowledge in the management of emergency colorectal conditions and should serve as practical text for clinicians managing colorectal conditions in the emergency setting.

Association of Colonic Diverticula with Colorectal Adenomas and Cancer

Background and Objectives: Conflicting evidence is reported regarding any association between colonic diverticula with colorectal adenomas or cancer. The present study aimed to evaluate, in a cohort of Caucasian patients, the association between colonic diverticula and colorectal polyps and cancer. Materials and Methods: All consecutive patients undergoing colonoscopy at our institution were included in the study. The presence and location of diverticula, polyps, and cancers were recorded. Histologically, polyps were classified as adenoma (with low or high dysplasia), hyperplastic, or inflammatory. The relative risk of the association of polyps and cancer with diverticula was assessed. Multiple logistic regression analyses, including age, sex, family history for colorectal cancer (CRC), and family history for diverticula, were carried out. Results: During the study period, 1490 patients were enrolled; 37.2% (n = 555) showed colonic diverticula or polyps or CRC (308 males, mean age 66 years). Particularly, 12.3% (n = 183) patients presented only diverticula, 13.7% (n = 204) only polyps or cancer, 11.3% (n = 168) both diseases, and 62.7% (n = 935) neither diverticula nor polyps and cancer. A total of 38 patients presented colorectal cancer, 17 of which had also diverticula. A significant increase in relative risk (RR 2.81, 95% CI 2.27-3.47, p < 0.0001) of colorectal adenoma and cancer in patients with colonic diverticula was found. At multivariate analysis, only diverticula resulted to be significantly associated with colorectal adenomas and cancer (Odds Ratio, OR 3.86, 95% CI 2.90-5.14, p < 0.0001). Conclusions: A significant association of colonic diverticula with colorectal adenoma or cancer was found. This implies that patients with colonic diverticula require a vigilant follow-up procedure for the prevention of colorectal cancer from those applicable to the general population.

Dietary pattern and its association with right-colonic diverticulosis

BACKGROUND AND AIM

In East Asia, colonic diverticulosis develops most commonly in the right colon and is known to have different characteristics compared with left-sided one. This study was designed to investigate whether right-colonic diverticulosis is associated with posteriori dietary patterns.

METHODS

We retrospectively reviewed medical records of prospectively collected cohort that received health check-up in Korea between May 2011 and January 2012. Their anthropometric data, biochemical results, medication history, underlying diseases, colonoscopic findings, and dietary data obtained from semi-quantitative food-frequency questionnaire were analyzed. Three dietary patterns were identified using factor analysis: healthy dietary pattern (vegetables, fish, seaweed, fruits, and beans), meat dietary pattern (red meat, processed meat/fish, fried noodle, poultry, and cephalopods), and snack dietary pattern (bread, sweets, dairy products, nuts, and rice cake).

RESULTS

Out of the total 1911 patients, 203 (10.6%) had right-colonic diverticulosis, 21 (1.1%) had pan-colonic diverticulosis, and 12 (0.6%) had left-colonic diverticulosis. Among the total, none of the three patterns were associated with right-colonic diverticulosis, under adjustment with age, gender, body mass index, metabolic syndrome, and total energy intake. However, among women, meat dietary pattern was positively associated with right-colonic diverticulosis (odds ratio 1.866, 95% confidence interval: 1.0983-3.173, P = 0.021).

CONCLUSION

This study demonstrated that meat dietary pattern is positively associated with right-colonic diverticulosis among women.

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.

Multifocal Versus Conventional Unifocal Diverticulitis: A Comparison of Clinical and Transcriptomic Characteristics

BACKGROUND

The management of diverticulitis is compromised by difficulty in identifying patients who require surgery for recurrent or persistent disease. Here, we introduce the concept of multifocal diverticulitis (MFD), characterized by multiple episodes of diverticulitis occurring at different locations within the colon.

AIMS

To compare clinical characteristics, success of surgical management, and colonic transcriptomes of MFD patients to patients with conventional unifocal diverticulitis (UFD).

METHODS

This retrospective study included 404 patients with CT-confirmed diverticulitis episodes. Patients with diverticulitis seen in at least two different colonic locations were classified as the MFD group and compared to the UFD group based on number of episodes, sites of disease, family history, surgeries performed, and postoperative recurrence. RNA-seq was conducted on full-thickness colonic tissues of ten MFD and 11 UFD patients.

RESULTS

Twenty-eight patients (6.9%) with MFD were identified. MFD patients had more diverticulitis episodes and were more likely to have positive family history, have right-sided disease, require surgery, and have recurrence after surgery. All MFD patients treated with segmental resection had recurrence, while recurrence was less common in patients undergoing more extensive surgery (P < 0.001). Using RNA-seq, we identified 69 genes that were differentially expressed between MFD and UFD patients. Significantly down-regulated genes were associated with immune response pathways.

CONCLUSIONS

MFD appears to be a more severe subset of diverticulitis with a possible genetic component. Transcriptomic data suggest that MFD may be associated with alteration of the immune response.

Epidemiology, Pathophysiology, and Treatment of Diverticulitis

Diverticulitis is a prevalent gastrointestinal disorder that is associated with significant morbidity and health care costs. Approximately 20% of patients with incident diverticulitis have at least 1 recurrence. Complications of diverticulitis, such as abdominal sepsis, are less likely to occur with subsequent events. Several risk factors, many of which are modifiable, have been identified including obesity, diet, and physical inactivity. Diet and lifestyle factors could affect risk of diverticulitis through their effects on the intestinal microbiome and inflammation. Preliminary studies have found that the composition and function of the gut microbiome differ between individuals with vs without diverticulitis. Genetic factors, as well as alterations in colonic neuromusculature, can also contribute to the development of diverticulitis. Less-aggressive and more-nuanced treatment strategies have been developed. Two multicenter, randomized trials of patients with uncomplicated diverticulitis found that antibiotics did not speed recovery or prevent subsequent complications. Elective surgical resection is no longer recommended solely based on number of recurrent events or young patient age and might not be necessary for some patients with diverticulitis complicated by abscess. Randomized trials of hemodynamically stable patients who require urgent surgery for acute, complicated diverticulitis that has not improved with antibiotics provide evidence to support primary anastomosis vs sigmoid colectomy with end colostomy. Despite these advances, more research is needed to increase our understanding of the pathogenesis of diverticulitis and to clarify treatment algorithms.

Animal Models of Diverticulosis: Review and Recommendations

Diverticulosis is a structural alteration of the colon tissue characterized by the development of pouch-like structures called diverticula. It afflicts a significant portion of the population in Western countries, with a higher prevalence among the elderly. Diverticulosis is believed to be the result of a synergetic interaction between inherent tissue weakness, diet, colonic microstructure, motility, and genetic factors. A validated etiology has, however, not yet been established. Non-surgical treatment is currently lacking due to this poor understanding, and surgical colon resection is the only long-term solution following recurrent complications. With rising prevalence, the burden of diverticulosis on patients and hospital resources has increased over the past several years. More efficient and less invasive treatment approaches are, thus, urgently needed. Animal models of diverticulosis are crucial to enable a preclinical assessment and evaluation of such novel approaches. This review discusses the animal models of diverticulosis that have been proposed to date. The current models require either a significant amount of time to develop diverticulosis, present a relatively low success rate, or seriously deteriorate the animals' systemic health. Recommendations are thus provided to address these pitfalls through the selection of a suitable animal and the combination of multiple risk factors for diverticulosis.

Hepato-bronchial fistula secondary to perforated sigmoid diverticulitis: a case report

Background

Patients with diverticulitis are predisposed to hepatic abscesses via seeding through the portal circulation. Hepatic abscesses are well-documented sequelae of diverticulitis, however instances of progression to hepato-bronchial fistulization are rare. We present a case of diverticulitis associated with hepatic abscess leading to hepato-bronchial fistulization, which represents a novel disease course not yet reported in the literature.

Case Presentation

A 61-year-old Caucasian man presented with a history of unintentional weight loss and dyspnea both at rest and with exertion. He had a significant tobacco and alcohol misuse history. A massive right-sided pleural effusion was found on chest X-ray, which responded partially to chest tube insertion. A computed tomography scan of his thorax confirmed the presence of innumerable lung abscesses as well as a complex pleural effusion. An indeterminate tiny air pocket at the dome of the liver was also noted. A follow-up computed tomography scan of his abdomen revealed a decompressed hepatic abscess extending into the right pleural space and the right lower lobe. A sigmoid-rectal fistula was also revealed with focal colonic thickening, presumed to be the sequelae of remote or chronic diverticulitis. An interventional radiologist inserted a percutaneous drain into the decompressed hepatic abscess and the instillation of contrast revealed immediate filling of the right pleural space, lung parenchyma, and bronchial tree, confirming a hepato-bronchial fistula. After two concurrent chest tube insertions failed to drain the remaining pleural effusion completely, surgical lung decortication was conducted. Markedly thickened pleura were seen and a significant amount of gelatinous inflammatory material was debrided from the lower thoracic cavity. He recovered well and was discharged 10 days post-thoracotomy on oral antibiotics. The percutaneous liver abscess tube was removed 3 weeks post-discharge from hospital after the drain check revealed that the fistula and abscess had entirely resolved.

Conclusions

Refractory right-sided pleural effusion combined with constitutional symptoms should alert clinicians to search for possible hepatic abscess, especially in the context of diverticulitis. The rupture of an untreated hepatic abscess could lead to death from profound sepsis or rarely, as in this case, a hepato-bronchial fistula. Timely investigation and a multidisciplinary treatment approach can lead to improved patient outcomes.

Association Between Colonic Diverticulosis and Erectile Dysfunction: A Nationwide Population-Based Study

We investigated whether colonic diverticulosis (CD) is associated with an increased risk of the subsequent development of erectile dysfunction (ED).We identified 2879 patients, diagnosed with CD between 1998 and 2011 from the Taiwan National Health Insurance Research Database as the study cohort. Patients in a comparison cohort were frequency-matched with those in the CD cohort at a ratio of 1:4, frequency matched according to age (in 5-year bands) and year of CD diagnosis. The patients were followed-up until ED development, withdrawal from the National Health Insurance system, or the end of 2011. For both cohorts, the overall and age-specific incidence density rates of ED (per 1000 person-years) were calculated. The effects of age, CD, and other comorbidities on the risk of ED development were examined using Cox proportional hazards regression models.The average follow-up durations were 4.76 years and 4.97 years for the CD patients and comparison cohorts, respectively. The overall incidence of ED was 1.70-fold higher in the CD cohort than in the comparison cohort (2.92 and 1.71 per 1000 person-years, respectively). Colonic diverticulosis was an independent risk factor for subsequent ED development (adjusted HR [aHR] = 1.56, 95% confidence interval = 1.07-2.28) in a multivariate Cox proportional hazards regression model.In this large retrospective cohort study, CD was associated with future ED development. Additional studies are required for validating our results.

Morphologic Basis for Developing Diverticular Disease, Diverticulitis, and Diverticular Bleeding

Diverticula of the colon are pseudodiverticula defined by multiple outpouchings of the mucosal and submucosal layers penetrating through weak spots of the muscle coat along intramural blood vessels. A complete prolapse consists of a diverticular opening, a narrowed neck, and a thinned diverticular dome underneath the serosal covering. The susceptibility of diverticula to inflammation is explained by local ischemia, translocation of pathogens due to retained stool, stercoral trauma by fecaliths, and microperforations. Local inflammation may lead to phlegmonous diverticulitis, paracolic/mesocolic abscess, bowel perforation, peritonitis, fistula formation, and stenotic strictures. Diverticular bleeding is due to an asymmetric rupture of distended vasa recta at the diverticular dome and not primarily linked to inflammation. Structural and functional changes of the bowel wall in diverticular disease comprise: i) Altered amount, composition, and metabolism of connective tissue; ii) Enteric myopathy with muscular thickening, deranged architecture, and altered myofilament composition; iii) Enteric neuropathy with hypoganglionosis, neurotransmitter imbalance, deficiency of neurotrophic factors and nerve fiber remodeling; and iv) Disturbed intestinal motility both in vivo (increased intraluminal pressure, motility index, high-amplitude propagated contractions) and in vitro (altered spontaneous and pharmacologically triggered contractility). Besides established etiologic factors, recent studies suggest that novel pathophysiologic concepts should be considered in the pathogenesis of diverticular disease.

Prevalence and risk factors of asymptomatic colorectal diverticulosis in Taiwan

BACKGROUND

To investigate the prevalence and risk factors of asymptomatic colorectal diverticulosis in Taiwanese general population.

METHODS

From January 2009 to December 2011, consecutive asymptomatic subjects undergoing a health check-up were evaluated by colonoscopy. The colorectal diverticulosis was assessed, and a medical history and demographic data were obtained from each subject. Logistic regression analysis was conducted to search the risk factors of colorectal diverticulosis.

RESULTS

Of the 1899 asymptomatic subjects, the prevalence of colorectal diverticulosis was 13.5%. On univariate logistic regression analysis, age over 60 years old, male, adenomatous polyp, current smoking and heavy alcohol consumption were significantly associated with diverticulosis. Multivariate logistic regression analysis revealed that age over 60 years old (relative risk [RR], 2.57; 95% confidence interval [CI], 1.64-6.47), adenomatous polyps (RR, 2.18; 95% CI, 1.18-4.61) and heavy alcohol consumption (RR, 1.82; 95% CI, 1.04-3.08) were independent predictors for colorectal diverticulosis.

CONCLUSIONS

The prevalence of asymptomatic colorectal diverticulosis was 13.5% in Taiwan. Age over 60 years old, adenomatous polyp and heavy alcohol consumption may affect the risk of development of the disease.

Diverticular disease as a chronic gastrointestinal condition: experience from a specialist clinic

BACKGROUND

Although diverticular disease is a prevalent condition and a significant burden on the healthcare system, care is devolved across gastrointestinal, GP, and colorectal surgery clinics. We created a specialist Diverticular Disease Clinic to streamline care, enhance evidence-based practice and provide a base for research. The aim of this study was to assess patient referral sources, predictors of persistent disease and surgical outcomes.

METHODS

We retrospectively reviewed all patients attending our clinic. Patients younger than 50 years of age on initial presentation were considered 'younger' patients. Persistent symptoms lasted for at least 3 months.

RESULTS

Overall, 177 patients had confirmed diverticular disease. Patients were referred following hospital admission (82 patients, 46.3%) or from the community (95 patients, 53.7%). Ninety-five patients (53.7%) had persistent symptoms. Patients with more than two episodes of diverticulitis were more likely to have persistent symptoms (P<0.0001).Following hospitalization, younger patients were 3.98 times more likely to develop persistent symptoms (P=0.04). This was independent of the severity of the original infection, as a low peak C-reactive protein level of less than 50 mg/L was associated with persistent symptoms (odds ratio=3.62, P=0.03). Over the study period, 12 patients (6.9%) had elective surgery.

CONCLUSION

There is demand for dedicated care for patients with persistent symptoms from diverticular disease. Specialized clinics are a model for this care, provided by either gastroenterologists or surgeons, in centres with adequate demand. Our findings reinforce the hypotheses that chronic abdominal pain in diverticular disease may be related to sensation abnormalities similar to postinfective irritable bowel syndrome.

Constipation is not associated with colonic diverticula: a multicenter study in Japan

BACKGROUND

The association of diverticula with bowel habits is unclear. We therefore analyzed the association between diverticula and bowel habits in over 1000 Japanese individuals.

METHODS

Japanese subjects who underwent total colonoscopies at seven centers in Japan from June to September 2013 were analyzed. Bowel habits were evaluated using the Gastrointestinal Symptom Rating Scale, and stool form was assessed using a part of the Bristol Scale and Rome ΙΙΙ criteria. Diverticula were diagnosed by colonoscopy with a transparent soft-short hood.

KEY RESULTS

The study evaluated 1066 subjects, 648 males and 418 females (ratio, 1.55 : 1), of mean age 63.9 ± 13.0 years. After adjusting for age and sex, the presence of constipation was associated with a significantly reduced likelihood of diverticula (odds ratio [OR] = 0.70, 95% confidence interval [CI] 0.52-0.93). When assessed according to the location of diverticula, the presence of constipation was associated with a significantly decreased likelihood of left-sided (OR = 0.39, 95% CI 0.16-0.93), but not right-sided (OR = 1.10, 95% CI 0.48-2.53), diverticula. Furthermore, stool form was unrelated with the presence or absence of diverticula.

CONCLUSIONS & INFERENCES

The wide-spread hypothesis that constipation was associated with colonic diverticula was not supported. Rather, we found that the absence of diverticula was associated with constipation, suggesting the need to reassess the etiology of colonic diverticula.

[Anatomy and pathogenesis of diverticular disease]

BACKGROUND

Although diverticular disease is one of the most frequent gastrointestinal disorders the pathogenesis is not yet sufficiently clarified.

OBJECTIVES

The aim is to define the anatomy and pathogenesis of diverticular disease considering the risk factors and description of structural and functional alterations of the bowel wall.

METHODS

This article gives an appraisal of the literature, presentation and evaluation of classical etiological factors, analysis and discussion of novel pathogenetic concepts.

RESULTS

Colonic diverticulosis is defined as an acquired out-pouching of multiple and initially asymptomatic pseudodiverticula through muscular gaps in the colon wall. Diverticular disease is characterized by diverticular bleeding and/or inflammatory processes (diverticulitis) with corresponding complications (e.g. abscess formation, fistula, covered and open perforation, peritonitis and stenosis). Risk factors for diverticular disease include increasing age, genetic predisposition, congenital connective tissue diseases, low fiber diet, high meat consumption and pronounced overweight. Alterations of connective tissue cause a weakening of preformed exit sites of diverticula and rigidity of the bowel wall with reduced flexibility. It is assumed that intestinal innervation disorders and structural alterations of the musculature induce abnormal contractile patterns with increased intraluminal pressure, thereby promoting the development of diverticula. Moreover, an increased release of pain-mediating neurotransmitters is considered to be responsible for persistent pain in chronic diverticular disease.

CONCLUSIONS

According to the present data the pathogenesis of diverticular disease cannot be attributed to a single factor but should be considered as a multifactorial event.

Left colon acute diverticulitis: an update on diagnosis, treatment and prevention

Diverticulosis of the colon is a common disease with an increasing incidence in Western Countries. It represents a significant burden for National Health Systems in terms of costs. Most people with diverticulosis remain asymptomatic, about one quarter of them will develop an episode of symptomatic diverticular disease and up to 5% an episode of acute diverticulitis (AD). AD shows an increasing prevalence. Recently, progresses have been reached about the etiology, pathogenesis, natural course of diverticular disease and its complications; improvements about the diagnosis and treatment of AD have been achieved. However, the treatment options are not well defined because of a lack of solid evidence: there are few systematic reviews and well conducted trials to guide decision-making in the treatment of AD and in the prevention of its recurrences. This review describes the recent evidence about diagnosis, treatment and prevention of AD.

Increased diverticular complications with nonsteriodal anti-inflammatory drugs and other medications: a systematic review and meta-analysis

AIM

Complications of colonic diverticula, perforation and bleeding are a source of morbidity and mortality. A variety of drugs have been implicated in these complications. We present a systemic review and meta-analysis of the literature to assess the importance of this relationship.

METHOD

A systematic review of articles in PubMed, Cochrane Reviews, Embase and Google Scholar was undertaken in February 2013. An initial literature search yielded 2916 results that were assessed for study design and topicality. Twenty-three articles were included in the review. A qualitative data synthesis was conducted using forest plots of studies comparing single medication with complications.

RESULTS

Individual studies demonstrated the odds of perforation and abscess formation with nonsteridal anti-inflammatory drugs (NSAIDs) (1.46-10.30), aspirin (0.66-2.40), steroids (2.17-31.90) and opioids (1.80-4.51) and the odds of bleeding with NSAIDs (2.01-12.60), paracetamol (0-3.75), aspirin (1.14-3.70) and steroids (0.57-5.40). Pooled data showed significantly increased odds of perforation and abscess formation with NSAIDs (OR = 2.49), steroids (OR = 9.08) and opioids (OR = 2.52). They also showed increased odds of diverticular bleeding from NSAIDs (OR = 2.69), aspirin (OR = 3.24) and calcium-channel blockers (OR = 2.50). Most studies did not describe the duration or dosage of medication used and did not systematically describe the severity of diverticular complications.

CONCLUSION

Various common medications are implicated in complications of diverticular disease.

Management of acute diverticulitis and its complications

Colonic diverticular disease is a common condition, and around a quarter of people affected by it will experience acute symptoms at some time. The most common presentation is uncomplicated acute diverticulitis that can be managed conservatively with bowel rest and antibiotics. However, some patients will present with diverticular abscesses or purulent or faeculent peritonitis due to perforated diverticular disease. Whilst most mesocolic abscesses can be managed with percutaneous drainage alone, pelvic abscesses are associated with a higher rate of future complications and usually require percutaneous drainage followed by interval sigmoid resection. Patients who require emergency surgery for complicated acute diverticulitis most commonly undergo a Hartmann's procedure, although resection with primary anastomosis and laparoscopic peritoneal lavage have emerged as alternative treatment options for patients with purulent peritonitis in recent years. However, robust evidence from randomized trials is lacking for these alternative procedures, and the studies that have reported good outcomes from them have included carefully selected patient groups. There has been a move away from recommending elective prophylactic colectomy after two episodes of acute diverticulitis in the light of evidence that most patients will not experience a significant recurrence of their symptoms; elective surgery is indicated for those with ongoing symptoms, pelvic abscesses, complications-such as fistulating disease, strictures or recurrent diverticular bleeding-and those who are at high risk of perforation during future episodes, for example, due to immunosuppression, chronic renal failure or collagen-vascular diseases.

Increase in colonic diverticulosis and diverticular hemorrhage in an aging society: lessons from a 9-year colonoscopic study of 28,192 patients in Japan

PURPOSES

Colonoscopic evidence of epidemiological trends in diverticulosis and diverticular bleeding is scarce. We evaluated trends in diverticular disease and associated factors over 9 years.

METHODS

Twenty-eight thousand one hundred ninety-two patients who underwent colonoscopy at an emergency hospital were reviewed from an electronic endoscopy database. Diverticula were classified as right-sided, left-sided, and bilateral types, and time trends in the proportion in diverticulosis, type, and diverticular bleeding were determined. Associations of age (≤39, 40-59, and ≥60 years), sex, and year increase with disease and odds ratios were estimated using logistic regression.

RESULTS

Diverticulosis was identified in 6,150 patients (20.3 %; mean age, 67.6 years) and was predominantly right-sided (48.0 %). Diverticular bleeding was found in 427 (1.5 %; mean age, 69.7 years) and was predominantly bilateral (47.0 %). Proportion of colonic diverticulosis increased significantly (P < 0.01 for trend) from 66.0 % (1,424/2,157) in 2003 to 70.1 % (2,914/4,159) in 2011 and was associated (P < 0.01) with an increased number of patients aged ≥60 years. Proportion of diverticular bleeding increased significantly (P < 0.01 for trend) from 1.02 % (22/2,157) in 2003 to 1.67 % (69/4,159) in 2011 and was associated (P = 0.04) with an increased number of patients aged 40-59 years. Diverticulosis, right and bilateral type, and diverticular bleeding were independently associated with the 9-year trend after adjustment by age and sex.

CONCLUSIONS

Colonic diverticulosis and diverticular bleeding are prevalent and increasing in Japan. Given the significant association of age with this trend, both diseases can be expected to increase for decades to come.

Review article: The pathogenesis and management of acute colonic diverticulitis

BACKGROUND

Acute diverticulitis, defined as acute inflammation associated with a colonic diverticulum, is a common emergency presentation managed by both surgeons and physicians. There have been advances in both the medical and the surgical treatments offered to patients in recent years.

AIM

To review the current understanding of the aetiology and treatment of acute diverticulitis.

METHODS

A search of PubMed and Medline databases was performed to identify articles relevant to the aetiology, pathogenesis and management of acute diverticulitis.

RESULTS

There are 75 hospital admissions per year for acute diverticulitis per 100,000 of the population in the United States. Recent reports suggest a 26% increase in admissions over a 7-year period. Factors predisposing to the development of acute diverticulitis include obesity, smoking, diet, lack of physical activity and medication use such as aspirin and nonsteroidal anti-inflammatory drugs. The condition is associated with a low mortality of about 1% following medical therapy, rising to 4% in-hospital mortality in those requiring surgery. There is limited evidence on the efficacy of individual antibiotic regimens, and antibiotic treatment may not be required in all patients. The rates of recurrence reported for patients with acute diverticulitis following medical management vary from 13% to 36%. The surgical management of those patients who fail medical treatment has moved towards a laparoscopic nonresectional approach; however, the evidence supporting this is limited.

CONCLUSIONS

Further high-quality randomised controlled trials are required of both medical and surgical treatments in patients with acute diverticulitis, if management is to be evidence-based.

The enteric serotonergic system is altered in patients with diverticular disease

OBJECTIVE

Disturbances of the enteric serotonergic system have been implicated in several intestinal motility disorders. Patients with diverticular disease (DD) have been reported to exhibit abnormal intestinal motility and innervation patterns. Gene expression profiles of the serotonergic system and distribution of the serotonin type 4 receptor (5HT-4R) were thus studied in patients with DD.

DESIGN

Colonic specimens from patients with DD and controls were subjected to quantitative PCR for serotonin receptors 2B, 3A, 4, serotonin transporter and synthesising enzyme tryptophan hydroxylase. Localisation of 5HT-4R was determined by dual-label immunocytochemistry using smooth muscle actin (α-SMA) and pan-neuronal markers (PGP 9.5) and quantitative analysis was carried out. Site-specific gene expression analysis of 5HT-4R was assessed within myenteric ganglia and muscle layers. Correlation of 5HT-4R with muscarinic receptors 2 and 3 (M2R, M3R) messenger RNA expression was determined.

RESULTS

5HT-4R mRNA expression was downregulated in the tunica muscularis and upregulated in the mucosa of patients with DD, whereas the other components of the serotonergic system remained unchanged. 5HT-4R was detected in ganglia and muscle layers, but was decreased in the circular muscle layer and myenteric ganglia of patients with DD. 5HT-4R mRNA expression correlated with M2R/M3R mRNA expression in controls, but not in patients with DD.

CONCLUSIONS

The serotonergic system is compromised in DD. Altered expression of 5HT-4R at mRNA and protein levels may contribute to intestinal motor disturbances reported in patients with DD. The findings support the hypothesis that DD is associated and possibly promoted by an enteric neuromuscular pathology.

Clinical and X-ray features of diverticulosis of the colon: Analysis of 31 cases

AIM: To summarize the clinical and X-ray features of diverticulosis of the colon.

METHODS: Clinical and X-ray data for 31 patients with diverticulosis of the colon who were diagnosed and underwent a double-contrast barium enema at our hospital from 2000 to 2011 were analyzed retrospectively.

RESULTS: Among the 31 cases, the eldest was 85 years old, and the youngest was 40 years. The average age was 63. Pathological changes in 15 cases were confined to the ascending colon, and involved the cecum and the ascending colon in 7 cases, the cecum, the ascending colon and the transverse colon in 5 cases, and the whole colon in 4 cases. Fourteen cases had diverticulitis.

CONCLUSION: The middle-aged and the elderly are prone to develop diverticulosis of the colon, mostly on the right-side, and with diverticulitis. The double contrast barium enema is a useful method for detection of diverticulosis of the colon.

Colonic diverticular disease: abnormalities of neuromuscular function

Although diverticular disease of the colon (diverticulosis) is a frequent finding in Western countries, its pathophysiologic grounds are still only partially understood. Traditionally considered as an age-related condition, colonic diverticulosis is probably the final result of several factors concurring together to determine the anatomo-functional abnormalities eventually causing outpouching of the viscus' mucosa. Among these factors, a relevant role seems to be played by an abnormal neuromuscular function of the large bowel, as shown by abnormal myoelectrical and motor function repeatedly described in these patients, as well as by altered visceral perception. These anomalies might be related to the recent demonstration of derangement of enteric innervation (especially involving interstitial cells of Cajal and enteric glial cells), mucosal neuropeptides, and mucosal inflammation. The latter may have a role of paramount importance in the development of visceral hypersensitivity, responsible for abdominal pain in a subset of patients.

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

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

Relationship between intestinal gas and the development of right colonic diverticula

BACKGROUNDS/AIMS

High intraluminal pressure has been reported to cause left colonic diverticula. However, the pathophysiology of right colonic diverticula is still unclear. Methane gas has been reported to delay small intestinal transit and to increase intraluminal pressure. The aim of this study was to evaluate the relationship between right colonic diverticula and intestinal gas produced by enteric bacteria.

METHODS

Lactulose breath tests were performed in 30 patients who were diagnosed with right colonic diverticula via colonoscopy. The control group consisted of 30 healthy adults with no specific symptoms or medical histories. A hydrogen or methane producer was defined in 2 ways: either one that exhibited a breath hydrogen level ≥ 20 ppm (methane ≥ 10 ppm) baseline or one that exhibited an increase in breath hydrogen ≥ 20 ppm (methane ≥ 10 ppm) above baseline within the first 90 minutes of the test.

RESULTS

The lactulose breath test (LBT) positivity in the diverticular group and the control group were 40.0% and 33.3%, respectively, without a statistically significant difference. The concentrations of methane and hydrogen gas measured by LBT increased over time, but there was no significant difference between the control and the diverticular groups.

CONCLUSIONS

There was no significant relationship between right colonic diverticula and intestinal gases produced by enteric bacteria. However, time-dependent formation of diverticula should be taken into consideration, therefore long-term, large-scale follow-up studies may reveal further pathogenesis of right colonic diverticulosis.

Clinical characteristics of colonic diverticulosis in Korea: a prospective study

BACKGROUND/AIMS

The prevalence of colonic diverticulosis has been reported to be lower in Korea than in Western countries. This disease also shows markedly different characteristics in the Korean population. We describe herein a prospective investigation, based on colonoscopic examination, of the prevalence, clinical characteristics, and factors associated with colonic diverticulosis in Korea.

METHODS

The prevalence of colonic diverticulosis has been reported to be lower in Korea than in Western countries. This disease also shows markedly different characteristics in the Korean population. We describe herein a prospective investigation, based on colonoscopic examination, of the prevalence, clinical characteristics, and factors associated with colonic diverticulosis in Korea.

RESULTS

The overall prevalence of colonic diverticulosis was 12.1% (103/848). The right side of the colon was involved in 84.5% of patients (87/103); patients with right side diverticula were, on average, younger than those with left side diverticulosis (p = 0.014). Multiple diverticula were observed in 60.2% (62/103) of patients. Age greater than 60 years, a high-fat diet, and alcohol consumption were significantly associated with the presence of colonic diverticulosis (p < 0.05).

CONCLUSIONS

The prevalence of colonic diverticulosis in Korea is increasing and is most commonly located in the right side of the colon. Further, old age and diet may affect the risk of development of this disease.

Manipulating digestion with foods designed to change the physical characteristics of digesta

We explore how foods can be designed to modulate digestion and to promote health by changing the physical properties of digesta. The physical characteristics of digesta are discussed along with their impact on the physiology of digestion with special reference to sites where these characteristics are likely to influence digestive efficiency. Evidence is reviewed regarding the effects of supplementation with viscoactive agents on the flow and mixing of digesta in particular segments of the human gut that, by changing the rheology and liquid permeability of digesta in that segment, influence specific aspects of digestion and absorption.

Diverticular disease is associated with an enteric neuropathy as revealed by morphometric analysis

BACKGROUND

The pathogenesis of diverticular disease (DD) is attributed to several aetiological factors (e.g. age, diet, connective tissue disorders) but also includes distinct intestinal motor abnormalities. Although the enteric nervous system (ENS) is the key-regulator of intestinal motility, data on neuropathological alterations are limited. The study aimed to investigate the ENS by a systematic morphometric analysis.

METHODS

Full-thickness sigmoid specimens obtained from patients with symptomatic DD (n = 27) and controls (n = 27) were processed for conventional histology and immunohistochemistry using anti-HuC/D as pan-neuronal marker. Enteric ganglia, nerve and glial cells were quantified separately in the myenteric, external and internal submucosal plexus compartments.

KEY RESULTS

Compared to controls, patients with DD showed significantly (P < 0.05) (i) reduced neuronal density in all enteric nerve plexus, (ii) decrease of ganglionic nerve cell content in the myenteric plexus, (iii) decreased ganglionic density in the internal submucosal plexus, (iv) reduced glial cell density in the myenteric plexus, (v) decrease of ganglionic glial cell content in the myenteric plexus and increase in submucosal plexus compartments, (vi) increased glia index in all enteric nerve plexus. About 44.4% of patients with DD exhibited myenteric ganglia displaying enteric gliosis.

CONCLUSIONS & INFERENCES

Patients with DD show substantial structural alterations of the ENS mainly characterized by myenteric and submucosal oligo-neuronal hypoganglionosis which may account for intestinal motor abnormalities reported in DD. The morphometric data give evidence that DD is associated with structural alterations of the ENS which may complement established pathogenetic concepts.

Colonic Diverticulosis as a Risk Factor for Peritonitis in Chinese Peritoneal Dialysis Patients

Objectives

The risk of development of enteric peritonitis in Chinese peritoneal dialysis (PD) patients with colonic diverticulosis is not known. There have been no reports on whether colonic diverticulosis may affect peritonitis outcomes. The objectives of this study were to examine whether colonic diverticulosis is a risk factor for the development of enteric peritonitis and to study its influence on the outcome of enteric peritonitis.

Patients and Methods

All continuous ambulatory PD patients that had barium enema and colonoscopic examinations performed between January 1994 and January 2006 were included. They were divided into 2 groups: patients with diverticulosis and patients without diverticulosis. Their demographic and clinical characteristics, colonic examination findings, and peritonitis data were compared and analyzed.

Results

104 Chinese patients received 110 colonoscopies and 51 barium enema examinations. 25 patients (24.0%) had colonic diverticulosis. Patients with diverticulosis were older (65.4 ± 14.7 vs 58.4 ± 14.0 years, p = 0.033). The most common site of involvement of diverticulosis was the ascending colon (56%). 128 episodes of enteric peritonitis were recorded in 49 patients. Compared with patients without enteric peritonitis, more patients in the enteric peritonitis group had diverticulosis (38.8% vs 10.9%, p = 0.001) and diverticulosis most often involved the ascending colon (20.4% vs 7.3%, p = 0.082). Multivariate logistic regression analysis showed that the presence of diverticulosis (hazard ratio 5.17, 95% confidence interval 1.86 – 14.40; p = 0.002) and diverticulosis involving the ascending colon (hazard ratio 6.89, 95% confidence interval 1.43 – 33.32, p = 0.016) were independent risk factors for the development of enteric peritonitis. Enteric peritonitis in patients with diverticulosis had a higher but nonsignificant treatment failure rate (26.9% vs 18.4%, p = 0.282).

Conclusion

In this selected cohort of PD patients with indications of colonic examinations, diverticulosis, especially involving the ascending colon, may be a risk factor for the development of enteric peritonitis. Colonic diverticulosis does not appear to affect the outcome of enteric peritonitis. Further studies are warranted to determine ways to prevent enteric peritonitis in PD patients with diverticulosis.

Smoking increases the incidence of complicated diverticular disease of the sigmoid colon

BACKGROUND AND AIMS

The aim of this study was to establish whether smoking is associated with complicated diverticular disease and adverse outcomes of operative treatment of diverticular disease. Smoking has been associated with increased rate of perforations in acute appendicitis as well as failure of colonic anastomosis in patients resected for colonic tumours. It has also been suggested that smoking is a risk factor for complicated diverticular disease of the colon.

MATERIAL AND METHODS

Retrospective investigation of records of 261 patients electively operated for diverticular disease in Helsinki University Central Hospital during a period of five years.

RESULTS

The smokers underwent sigmoidectomy at a younger age than the non-smokers (p = 0.001) and they had an increased rate of perforations (p = 0.040) and postoperative recurrent diverticulitis episodes (p = 0.019).

CONCLUSIONS

We conclude that smoking increases the likelihood of complications in diverticulosis coli. The development of complicated disease also seems to proceed more rapidly in smokers.Key words: Sigmoid resection; laparoscopy; laparoscopic sigmoidectomy; smoking and diverticular disease; complicated diverticular disease; diverticulitis.

Management of Hinchey II diverticulitis

Colonic diverticulosis can either be asymptomatic or present with complications resulting in significant morbidity and mortality. A key presentation of complicated disease is abscess formation (Hinchey type II). The natural course of this is unclear and therefore treatments range from conservative approach with antibiotics and percutaneous guided drainage (PCD) to surgery. There is no clear consensus on the exact management strategy. A Medline based literature search specifically looking at studies dealing with Hinchey type II diverticulitis and its management was carried out. For comparison, five-year retrospective data of diverticular abscesses from our institution was collected and the outcome analysed. Various studies have looked into this aspect of the disease, elaborating on the significance of the size and location of the abscesses, the role of PCD, recurrence rates and the controversies regarding the need for elective surgery. Conservative treatment with antibiotics alone is effective in a majority of cases with a role for PCD in large safely accessible abscesses. Variable recurrence rates have been reported in literature and elective surgery should be planned for selected groups of patients.

Serotonin signaling in diverticular disease

Diverticulosis is extremely common in Western societies and is associated with complications in up to 15%of cases. Altered motility is an important feature of the pathogenesis of diverticular disease, and serotonin (5-HT) release is a primary trigger of gut motility. This study aims to determine whether colonic 5-HT signaling is altered in patients with diverticulosis or diverticulitis, and whether differences in serotonin signaling may distinguish patients with asymptomatic diverticulosis from those who develop disease specific complications. Sigmoid colon biopsies were obtained from healthy control subjects, individuals with asymptomatic diverticulosis, and those with a history of CT-proven diverticulitis within the preceding 6 months. The key elements of 5-HT signaling including content, release, and 5-HT transporter (SERT) expression were analyzed. A significant decrease in SERT transcript levels was present in the mucosa of patients with a history of diverticulitis when compared with controls, but not in those with asymptomatic diverticulosis. Mucosal 5-HT content, enterochromaffin (EC) cell numbers, and TpH-1 mRNA levels were comparable amongst the groups, as were basal and stimulated 5-HT release. Alterations in 5-HT signaling do not appear to be responsible for the development of diverticula. However, patients with a recent history of acute diverticulitis have a significant attenuation in SERT expression and function, likely secondary to previous inflammation. Our findings may explain the persistent symptoms of pain and altered motility so often observed in patients with diverticulitis long after recovery from the acute inflammatory response.

Prevention of complications and symptomatic recurrences in diverticular disease with mesalazine: a 12-month follow-up

In uncomplicated diverticular disease, treatment is aimed at relieving symptoms. The aim of the present study was to evaluate the efficacy of mesalazine for symptomatic relief of uncomplicated diverticular disease of the colon. Two hundred sixty-eight consecutive eligible outpatients (122 male, 146 female; age, 66.1 years; range, 31-81 years) were enrolled in four treatment schedules in a randomized fashion: Group R1 (66 patients), rifaximin, 200 mg bid; Group R2 (69 patients), rifaximin, 400 mg bid; Group M1 (67 patients), mesalazine, 400 mg bid; and Group M2 (66 patients), mesalazine, 800 mg bid. Treatments were administered for 10 days every month for 12 months. Clinical evaluations were performed at admission and at 3-month intervals for 12 months considering 12 clinical variables (upper and lower abdominal pain/discomfort, tenesmus, diarrhea, abdominal tenderness, fever, bloating, general illness, nausea, emesis, dysuria, bleeding) graded as 0 = no symptoms, 1 = mild, 2 = moderate, and 3 = severe. The Global Symptomatic Score (GSS) was calculated using the sum of each symptom score. Two hundred forty-four patients completed the 12- month study; 24 were discontinued (14 treated with rifaximin and 10 treated with mesalazine) either as voluntary dropouts or because they developed side effects and/or complications. Group M2 demonstrated a lower frequency of many symptoms after 6 and 12 months of treatment; the mean GSS was significantly lower in Group M2 after 6 and 12 months of therapy by both intention-to-treat and per-protocol analyses. Patients treated with mesalazine (Groups M1+M2) had a lower GSS than subjects treated with rifaximin (Groups R1+R2) during the 12-month follow-up period. We conclude that cyclic administration of mesalazine is effective for symptomatic relief of uncomplicated diverticular disease of the colon. Some symptoms showed greater improvement with mesalazine, 800 mg bid, than with the other treatment schedules.

Colonic epithelial ion transport is not affected in patients with diverticulosis

Background

Colonic diverticular disease is a bothersome condition with an unresolved pathogenesis. It is unknown whether a neuroepithelial dysfunction is present. The aim of the study was two-fold; (1) to investigate colonic epithelial ion transport in patients with diverticulosis and (2) to adapt a miniaturized Modified Ussing Air-Suction (MUAS) chamber for colonic endoscopic biopsies.

Methods

Biopsies were obtained from the sigmoid part of the colon. 86 patients were included. All patients were referred for colonoscopy on suspicion of neoplasia and they were without pathological findings at colonoscopy (controls) except for diverticulosis in 22 (D-patients). Biopsies were mounted in MUAS chambers with an exposed area of 5 mm². Electrical responses to various stimulators and inhibitors of ion transport were investigated together with histological examination. The MUAS chamber was easy to use and reproducible data were obtained.

Results

Median basal short circuit current (SCC) was 43.8 μA·cm^-2 (0.8 – 199) for controls and 59.3 μA·cm^-2 (3.0 – 177.2) for D-patients. Slope conductance was 77.0 mS·cm^-2 (18.6 – 204.0) equal to 13 Ω·cm² for controls and 96.6 mS·cm^-2 (8.4 – 191.4) equal to 10.3 Ω·cm² for D-patients. Stimulation with serotonin, theophylline, forskolin and carbachol induced increases in SCC in a range of 4.9 – 18.6 μA·cm^-2, while inhibition with indomethacin, bumetanide, ouabain and amiloride decreased SCC in a range of 6.5 – 27.4 μA·cm^-2, and all with no significant differences between controls and D-patients. Histological examinations showed intact epithelium and lamina propria before and after mounting for both types of patients.

Conclusion

We conclude that epithelial ion transport is not significantly altered in patients with diverticulosis and that the MUAS chamber can be adapted for studies of human colonic endoscopic biopsies.

Fiber and colorectal diseases: separating fact from fiction

Whilst fruits and vegetables are an essential part of our dietary intake, the role of fiber in the prevention of colorectal diseases remains controversial. The main feature of a high-fiber diet is its poor digestibility. Soluble fiber like pectins, guar and ispaghula produce viscous solutions in the gastrointestinal tract delaying small bowel absorption and transit. Insoluble fiber, on the other hand, pass largely unaltered through the gut. The more fiber is ingested, the more stools will have to be passed. Fermentation in the intestines results in build up of large amounts of gases in the colon. This article reviews the physiology of ingestion of fiber and defecation. It also looks into the impact of dietary fiber on various colorectal diseases. A strong case cannot be made for a protective effect of dietary fiber against colorectal polyp or cancer. Neither has fiber been found to be useful in chronic constipation and irritable bowel syndrome. It is also not useful in the treatment of perianal conditions. The fiber deficit - diverticulosis theory should also be challenged. The authors urge clinicians to keep an open mind about fiber. One must be aware of the truths and myths about fiber before recommending it.

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.