New paradigms in the management of diverticular disease

Recent updates on classification and unsolved issues of diverticular disease: a narrative review

Recently, a paradigm shift has occurred in the classification of diverticular disease and the understanding of its pathogenesis. Diverticular disease is now defined as a variety of clinically significant conditions such as diverticulitis, diverticular bleeding, symptomatic uncomplicated diverticular disease, and segmental colitis associated with diverticulosis. Low-grade inflammation, visceral hypersensitivity, abnormal intestinal motility, and genetic factors have emerged as the key contributors to the pathogenesis of diverticular disease. Routine antibiotic use is no longer recommended for all cases of diverticulitis, and simple recurrence is not an indication for surgical treatment. Early colonoscopy with proper preparation is recommended for the treatment of diverticular bleeding, although recent studies have not shown significant efficacy in preventing recurrence. The roles of dietary fiber, nonabsorbable antibiotics, 5-aminosalicylates, and probiotics in the prevention of diverticular disease are controversial and require further investigation.

Early Urinary Catheter Removal After Colectomy for Colovesical Fistula is Not Associated With Increased Postoperative Complications

BACKGROUND

Management of the bladder defect during colectomy for colovesical fistula (CVF) and recommendations for duration of urinary catheter drainage are inconsistent. This study aimed to determine if urinary catheter drainage duration was associated with postoperative complications.

METHODS

Retrospective single institution cohort study of patients undergoing resection for diverticular CVF from 2015 through 2021. Urinary catheter drainage was defined as Early (≤7 days postoperative and then subdivided into 1-2 days, 3-5 days, 6-7 days), and Late (>7 days postoperative). Primary outcome was a composite measure of postoperative bladder leak, surgical site infection-III, sepsis, reoperation, and postoperative length-of-stay ≥7 days.

RESULTS

There were 73 patients-64 Early group and 9 Late group. Composite measure between groups (Early 25% vs Late 33.33%, P = .688) was not significantly different. The Late group had more patients with large bladder defects (33.3% vs 7.8%, P = .054), significantly more patients who underwent suture repair (55.6% vs 14.1%, P = .01), and significantly more patients that had an intraoperative pelvic drain (66.7% vs 15.6%, P = .003). After propensity score inverse weighting, the Late group had significantly more cystogram-detected postoperative bladder leaks (P = .002) and ileus (P = .042) than the Early group. There were no bladder leaks or ileus in those who had urinary catheter removal on postoperative days 1-2.

CONCLUSIONS

Early urinary catheter removal was associated with no increase in bladder leaks and fewer postoperative complications after definitive management of CVF. Further investigation is required to determine if intraoperative bladder leak testing and postoperative cystograms are useful adjuncts in decision making.

Management and long-term outcomes of acute right colonic diverticulitis and risk factors of recurrence

Background

Acute right-sided colonic diverticulitis (RCD) is a common disease in Asian populations for which the optimal treatment remains controversial. The aim of this study was to investigate management and evaluate long-term outcomes of treatment in patients with acute RCD.

Methods

We retrospectively collected and analyzed clinical data for patients with acute RCD admitted to the Tongren Hospital, Shanghai Jiao Tong University School of Medicine from December 2015 to December 2020. The patients were divided into two groups, according to primary treatment strategy, which was either conservative treatment or surgical treatment.

Results

A total of 162 consecutive patients with acute RCD were enrolled in the study. There was no significant difference in age, sex, history of abdominal surgery, medical co-morbidities, fever, previous history of RCD, treatment success rate and incidence of complications between the conservative and surgery groups. However, the recurrence rate in conservative groups was significantly higher than in surgery groups (16.53% vs 2.44%, P = 0.020). And more frequent bowel movements and previous history of RCD increased the risk of recurrence of acute RCD. Moreover, there was no significant difference in either treatment success rate or the overall recurrence rate between the patients with uncomplicated diverticulitis and patients with complicated diverticulitis.

Conclusions

Surgical treatment is also safe and effective for acute RCD. Surgical treatment should mainly be considered for patients with acute RCD with recurrence risk factors (more frequent bowel movements and previous history of RCD) or with complicated acute RCD.

Right sided diverticulitis in western countries: A review

BACKGROUND

Although the treatment guidelines for left sided diverticulitis are clear, the management of right colonic diverticulitis is not well established. This disease can no longer be ignored due to significant spread throughout Asia.

AIM

To analyse epidemiology, diagnosis and treatment of right-sided diverticulitis in western countries.

METHODS

MEDLINE and PubMed searches were performed using the key words “right-sided diverticulitis’’, ‘‘right colon diverticulitis’’, ‘‘caecal diverticulitis’’, ‘‘ascending colon diverticulitis’’ and ‘‘caecum diverticula’’ in order to find relevant articles published until 2021.

RESULTS

A total of 18 studies with 422 patients were found. Correct diagnosis was made only in 32.2%, mostly intraoperatively or via CT scan. The main reason for misdiagnosis was a suspected acute appendicitis (56.8%). The treatment was a non-operative management (NOM) in 184 patients (43.6%) and surgical in 238 patients (56.4%), seven of which after NOM failure. Recurrence rate was low (5.45%), similar to eastern studies and inferior to left -sided diverticulitis. Recurrent patients were successfully conservatively retreated in most cases.

CONCLUSION

The management of right- sided diverticulitis is not well clarified in the western world and no selective guidelines have been considered even if principles are similar to those with left- sided diverticulitis. Wrong diagnosis is one of the most important problems and CT scan seems to be the best imaging modality. NOM offers a safe and effective treatment; surgery should be considered only in cases of complicated diverticulitis or if malignancy cannot be excluded. Further studies are needed to clarify the correct treatment.

Predictive factors for conservative treatment failure of right colonic diverticulitis

Purpose

Conservative treatment is the first-line therapy for acute colonic diverticulitis without severe complications, but treatment failure may increase hospitalization duration, medical costs, and morbidities. Usage of the modified Hinchey classification is insufficient to predict the outcome of conservative management. We aimed to investigate the clinical efficacy of the modified Hinchey classification and to evaluate predictive factors such as inflammatory markers for the failure of conservative management.

Methods

Patients diagnosed with right colonic diverticulitis undergoing conservative treatment at 3 hospitals between 2017 and 2019 were included. Patients were categorized into conservative treatment success (n = 494) or failure (n = 46) groups. Clinical characteristics and blood inflammatory markers were assessed.

Results

The conservative treatment failure group presented with more elderly patients (>50 years, P = 0.002), more recurrent episodes (P < 0.001), a higher lymphocyte count (P = 0.021), higher C-reactive protein (CRP) levels (P = 0.044), and higher modified Glasgow prognostic scores (P = 0.021). Multivariate analysis revealed that age of >50 years (odds ratio [OR], 2.54; 95% confidence interval [CI], 1.27–5.08; P = 0.008), recurrent episodes (OR, 4.78; 95% CI, 2.38–9.61; P < 0.001), and higher CRP levels (OR, 1.08; 95% CI, 1.03–1.12; P = 0.001) were predictive factors for conservative treatment failure, but not the modified Hinchey grade (P = 0.159).

Conclusion

Age of >50 years, recurrent episodes, and CRP levels are potential predictors for conservative management failure of patients with right-sided colonic diverticulitis. Further studies are warranted to identify candidates requiring early surgical intervention.

Diverticulitis: An Update From the Age Old Paradigm

For a disease process that affects so many, we continue to struggle to define optimal care for patients with diverticular disease. Part of this stems from the fact that diverticular disease requires different treatment strategies across the natural history- acute, chronic and recurrent.

To understand where we are currently, it is worth understanding how treatment of diverticular disease has evolved. Diverticular disease was rarely described in the literature prior to the 1900’s. In the late 1960’s and early 1970’s, Painter and Burkitt popularized the theory that diverticulosis is a disease of Western civilization based on the observation that diverticulosis was rare in rural Africa but common in economically developed countries. Previous surgical guidelines focused on early operative intervention to avoid potential complicated episodes of recurrent complicated diverticulitis (e.g., with free perforation) that might necessitate emergent surgery and stoma formation. More recent data has challenged prior concerns about decreasing effectiveness of medical management with repeat episodes and the notion that the natural history of diverticulitis is progressive. It has also permitted more accurate grading of the severity of disease and permitted less invasive management options to attempt conversion of urgent operations into the elective setting, or even avoid an operation altogether.

The role of diet in preventing diverticular disease has long been debated. A high fiber diet appears to decrease the likelihood of symptomatic diverticulitis. The myth of avoid eating nuts, corn, popcorn, and seeds to prevent episodes of diverticulitis has been debunked with modern data. Overall, the recommendations for “diverticulitis diets” mirror those made for overall healthy lifestyle – high fiber, with a focus on whole grains, fruits and vegetables.

Diverticulosis is one of the most common incidental findings on colonoscopy and the eighth most common outpatient diagnosis in the United States. Over 50% of people over the age of 60 and over 60% of people over age 80 have colonic diverticula. Of those with diverticulosis, the lifetime risk of developing diverticulitis is estimated at 10–25%, although more recent studies estimate a 5% rate of progression to diverticulitis. Diverticulitis accounts for an estimated 371,000 emergency department visits and 200,000 inpatient admissions per year with annual cost of 2.1–2.6 billion dollars per year in the United States. The estimated total medical expenditure (inpatient and outpatient) for diverticulosis and diverticulitis in 2015 was over 5.4 billion dollars. The incidence of diverticulitis is increasing.

Besides increasing age, other risk factors for diverticular disease include use of NSAIDS, aspirin, steroids, opioids, smoking and sedentary lifestyle. Diverticula most commonly occur along the mesenteric side of the antimesenteric taeniae resulting in parallel rows. These spots are thought to be relatively weak as this is the location where vasa recta penetrate the muscle to supply the mucosa. The exact mechanism that leads to diverticulitis from diverticulosis is not definitively known.

The most common presenting complaint is of left lower quadrant abdominal pain with symptoms of systemic unwellness including fever and malaise, however the presentation may vary widely. The gold standard cross-sectional imaging is multi-detector CT. It is minimally invasive and has sensitivity between 98% and specificity up to 99% for diagnosing acute diverticulitis. Uncomplicated acute diverticulitis may be safely managed as an out-patient in carefully selected patients. Hospitalization is usually necessary for patients with immunosuppression, intolerance to oral intake, signs of severe sepsis, lack of social support and increased comorbidities. The role of antibiotics has been questioned in a number of randomized controlled trials and it is likely that we will see more patients with uncomplicated disease treated with observation in the future

Acute diverticulitis can be further sub classified into complicated and uncomplicated presentations. Uncomplicated diverticulitis is characterized by inflammation limited to colonic wall and surrounding tissue. The management of uncomplicated diverticulitis is changing. Use of antibiotics has been questioned as it appears that antibiotic use can be avoided in select groups of patients. Surgical intervention appears to improve patient’s quality of life. The decision to proceed with surgery is recommended in an individualized manner.

Complicated diverticulitis is defined as diverticulitis associated with localized or generalized perforation, localized or distant abscess, fistula, stricture or obstruction. Abscesses can be treated with percutaneous drainage if the abscess is large enough. The optimal long-term strategy for patients who undergo successful non-operative management of their diverticular abscess remains controversial. There are clearly patients who would do well with an elective colectomy and a subset who could avoid an operation all together however, the challenge is appropriate risk-stratification and patient selection. Management of patients with perforation depends greatly on the presence of feculent or purulent peritonitis, the extent of contamination and hemodynamic status and associated comorbidities. Fistulas and strictures are almost always treated with segmental colectomy.

After an episode of acute diverticulitis, routine colonoscopy has been recommended by a number of societies to exclude the presence of colorectal cancer or presence of alternative diagnosis like ischemic colitis or inflammatory bowel disease for the clinical presentation. Endoscopic evaluation of the colon is normally delayed by about 6 weeks from the acute episode to reduce the risk associated with colonoscopy. Further study has questioned the need for endoscopic evaluation for every patient with acute diverticulitis. Colonoscopy should be routinely performed after complicated diverticulitis cases, when the clinical presentation is atypical or if there are any diagnostic ambiguity, or patient has other indications for colonoscopy like rectal bleeding or is above 50 years of age without recent colonoscopy.

For patients in whom elective colectomy is indicated, it is imperative to identify a wide range of modifiable patient co-morbidities. Every attempt should be made to improve a patient’s chance of successful surgery. This includes optimization of patient risk factors as well as tailoring the surgical approach and perioperative management. A positive outcome depends greatly on thoughtful attention to what makes a complicated patient “complicated”.

Operative management remains complex and depends on multiple factors including patient age, comorbidities, nutritional state, severity of disease, and surgeon preference and experience. Importantly, the status of surgery, elective versus urgent or emergent operation, is pivotal in decision-making, and treatment algorithms are divergent based on the acuteness of surgery. Resection of diseased bowel to healthy proximal colon and rectal margins remains a fundamental principle of treatment although the operative approach may vary.

For acute diverticulitis, a number of surgical approaches exist, including loop colostomy, sigmoidectomy with colostomy (Hartmann’s procedure) and sigmoidectomy with primary colorectal anastomosis. Overall, data suggest that primary anastomosis is preferable to a Hartman’s procedure in select patients with acute diverticulitis. Patients with hemodynamic instability, immunocompromised state, feculent peritonitis, severely edematous or ischemic bowel, or significant malnutrition are poor candidates. The decision to divert after colorectal anastomosis is at the discretion of the operating surgeon. Patient factors including severity of disease, tissue quality, and comorbidities should be considered. Technical considerations for elective cases include appropriate bowel preparation, the use of a laparoscopic approach, the decision to perform a primary anastomosis, and the selected use of ureteral stents.

Management of the patient with an end colostomy after a Hartmann’s procedure for acute diverticulitis can be a challenging clinical scenario. Between 20 – 50% of patients treated with sigmoid resection and an end colostomy after an initial severe bout of diverticulitis will never be reversed to their normal anatomy. The reasons for high rates of permanent colostomies are multifactorial. The debate on the best timing for a colostomy takedown continues. Six months is generally chosen as the safest time to proceed when adhesions may be at their softest allowing for a more favorable dissection. The surgical approach will be a personal decision by the operating surgeon based on his or her experience. Colostomy takedown operations are challenging surgeries. The surgeon should anticipate and appropriately plan for a long and difficult operation. The patient should undergo a full antibiotic bowel preparation. Preoperative planning is critical; review the initial operative note and defining the anatomy prior to reversal. When a complex abdominal wall closure is necessary, consider consultation with a hernia specialist. Open surgery is the preferred surgical approach for the majority of colostomy takedown operations. Finally, consider ureteral catheters, diverting loop ileostomy, and be prepared for all anastomotic options in advance.

Since its inception in the late 90’s, laparoscopic lavage has been recognized as a novel treatment modality in the management of complicated diverticulitis; specifically, Hinchey III (purulent) diverticulitis. Over the last decade, it has been the subject of several randomized controlled trials, retrospective studies, systematic reviews as well as cost-efficiency analyses. Despite being the subject of much debate and controversy, there is a clear role for laparoscopic lavage in the management of acute diverticulitis with the caveat that patient selection is key.

Segmental colitis associated with diverticulitis (SCAD) is an inflammatory condition affecting the colon in segments that are also affected by diverticulosis, namely, the sigmoid colon. While SCAD is considered a separate clinical entity, it is frequently confused with diverticulitis or inflammatory bowel disease (IBD). SCAD affects approximately 1.4% of the general population and 1.15 to 11.4% of those with diverticulosis and most commonly affects those in their 6th decade of life. The exact pathogenesis of SCAD is unknown, but proposed mechanisms include mucosal redundancy and prolapse occurring in diverticular segments, fecal stasis, and localized ischemia. Most case of SCAD resolve with a high-fiber diet and antibiotics, with salicylates reserved for more severe cases. Relapse is uncommon and immunosuppression with steroids is rarely needed. A relapsing clinical course may suggest a diagnosis of IBD and treatment as such should be initiated. Surgery is extremely uncommon and reserved for severe refractory disease.

While sigmoid colon involvement is considered the most common site of colonic diverticulitis in Western countries, diverticular disease can be problematic in other areas of the colon. In Asian countries, right-sided diverticulitis outnumbers the left. This difference seems to be secondary to dietary and genetic factors. Differential diagnosis might be difficult because of similarity with appendicitis. However accurate imaging studies allow a precise preoperative diagnosis and management planning. Transverse colonic diverticulitis is very rare accounting for less than 1% of colonic diverticulitis with a perforation rate that has been estimated to be even more rare. Rectal diverticula are mostly asymptomatic and diagnosed incidentally in the majority of patients and rarely require treatment. Giant colonic diverticula (GCD) is a rare presentation of diverticular disease of the colon and it is defined as an air-filled cystic diverticulum larger than 4 cm in diameter. The pathogenesis of GCD is not well defined.

Overall, the management of diverticular disease depends greatly on patient, disease and surgeon factors. Only by tailoring treatment to the patient in front of us can we achieve optimal outcomes.

Does inferior mesenteric artery ligation affect outcome in elective colonic resection for diverticular disease?

BACKGROUND

The aim of our study was to analyse the role of inferior mesenteric artery (IMA) ligation during elective colonic resection for diverticular disease (DD) with respect to surgical outcome.

METHODS

All patients who underwent elective laparoscopic or open colonic resection for DD from January 2006 to December 2012 were studied. The patients were divided into two groups based on IMA ligation or preservation. The primary end point was to compare anastomotic leakage in the two groups. The secondary end points were operative time, stoma formation, overall post-operative complications, restoration of bowel function and length of post-operative hospital stay.

RESULTS

During the study period, 219 elective colonic resections with primary anastomosis for DD were performed. A laparoscopic technique was employed in 132 (60.3%) cases. IMA ligation was performed in 66 patients (30.1%). Overall anastomotic leakage rate was 4.1%, 4.5% in IMA ligation and 3.9% in IMA preservation group, respectively (P = ns). Mean operative time was 225 ± 43.4 and 191 ± 41.7 min in IMA ligation and preservation group, respectively (P = 0.002). No differences were observed in the rate of overall complications, stoma formation, restoration of bowel function and post-operative length of hospital stay.

CONCLUSIONS

No differences were observed in surgical outcome in IMA ligation and preservation groups, particularly preservation or ligation of the IMA did not affect leakage rate.

Surgical Management of Diverticular Disease in the Elective Setting

Diverticulosis is a common condition that has increased in prevalence in industrialized countries over the past century. Estimates of developing diverticular disease in the United states range from 5% by 40 years of age up, to over 80% by age 80. It is estimated that approximately 20% of patients with diverticulosis develop diverticulitis over the course of their lifetime. Diverticular disease can be divided into simple and chronic diverticulitis with various sub categories. There are various instances and circumstances where elective resection is indicated for both complex and simple forms of this disease process. When planning surgery there are general preoperative considerations that are important to be reviewed prior to surgery. There are also more specific considerations depending on secondary problem attributed to diverticulitis, that is, fistula vs stricture. Today, treatment for elective resection includes open, laparoscopic and robotic surgery. Over the last several years we have moved away from open surgery to laparoscopic surgery for elective resection. With the advent of robotic surgery and introduction of 3D laparoscopic surgery the discussion of superiority, equivalence between these modalities, is and should remain an important discussion topic.

Limited evidence of abnormal intra-colonic pressure profiles in diverticular disease - a systematic review

AIM

Abnormal colonic pressure profiles and high intraluminal pressures are postulated to contribute to the formation of sigmoid colon diverticulosis and the pathophysiology of diverticular disease. This study aimed to review evidence for abnormal colonic pressure profiles in diverticulosis.

METHOD

All published studies investigating colonic pressure in patients with diverticulosis were searched in three databases (Medline, Embase, Scopus). No language restrictions were applied. Any manometry studies in which patients with diverticulosis were compared with controls were included. The Newcastle-Ottawa Quality Assessment Scale (NOS) for case-control studies was used as a measure of risk of bias. A cut-off of five or more points on the NOS (fair quality in terms of risk of bias) was chosen for inclusion in the meta-analysis.

RESULTS

Ten studies (published 1962-2005) met the inclusion criteria. The studies followed a wide variety of protocols and all used low-resolution manometry (sensor spacing range 7.5-15 cm). Six studies compared intra-sigmoid pressure, with five of six showing higher pressure in diverticulosis vs controls, but only two reached statistical significance. A meta-analysis was not performed as only two studies were above the cut-off and these did not have comparable outcomes.

CONCLUSION

This systematic review of manometry data shows that evidence for abnormal pressure in the sigmoid colon in patients with diverticulosis is weak. Existing studies utilized inconsistent methodology, showed heterogeneous results and are of limited quality. Higher quality studies using modern manometric techniques and standardized reporting methods are needed to clarify the role of colonic pressure in diverticulosis.

Acute colonic diverticulitis: an update on clinical classification and management with MDCT correlation

Currently, the most commonly used classification of acute colonic diverticulitis (ACD) is the modified Hinchey classification, which corresponds to a slightly more complex classification by comparison with the original description. This modified classification allows to categorize patients with ACD into four major categories (I, II, III, IV) and two additional subcategories (Ia and Ib), depending on the severity of the disease. Several studies have clearly demonstrated the impact of this classification for determining the best therapeutic approach and predicting perioperative complications for patients who need surgery. This review provides an update on the classification of ACD along with a special emphasis on the corresponding MDCT features of the different categories and subcategories. This modified Hinchey classification should be known by emergency physicians, radiologists, and surgeons in order to improve patient care and management because each category has a specific therapeutic approach.

Intraoperative diagnosis of solitary cecal diverticulum not requiring surgery: is appendectomy indicated?

Aim

To compare experience with solitary cecal diverticulum (SCD) with literature on the indication for appendectomy in cases of solitary cecal diverticulitis.

Methods

We retrospectively reviewed all cases of SCD in our institution from September 2011 to March 2013. Data on sex, age, ethnic origin, presence of pain in the right iliac fossa, duration of symptoms, diagnosis, management, intraoperative findings, histologic examination, hospital stay, complications, and follow-up were reviewed and analyzed. We compared this to related literature reported between 2000 and 2015.

Results

In the study period, 10 patients presented with an SCD. Male sex and Asian origin were predominant. All patients had pain in the right iliac fossa, with a duration of 2–5 days. In nine cases the diagnosis was made by clinical examination and laboratory testing. One patient who had undergone a previous appendectomy was diagnosed with SCD by computed tomography. This last patient was treated conservatively, four patients were treated with resection of the cecum “en bloc” with the last jejunal loop and appendix, and the other five patients were treated with appendectomies. Two patients had minor complications. All patients were followed up for a minimum of 12 to a maximum of 24 months. No recurrence was recorded in either the case treated conservatively or the cases treated by appendectomies.

Conclusions

In cases of operative but conservative treatment for SCD, appendectomy could be justified to avoid misdiagnosis in case of future episodes of solitary cecal diverticulitis.

Diverticulitis in the Young

Background: Colonic diverticulitis is relatively uncommon in young patients, especially those younger than 40 years. We compared demographic data, clinical presentation, management, and clinical course of diverticulitis in patients ≤40 years old compared with patients >40 years old. Methods: This study included all patients who presented to the emergency department with a diagnosis of diverticulitis between October 1, 2009 and September 30, 2010. Patients were divided into 2 groups: group 1 (≤40 years old) and group 2 (>40 years old). Demographic characteristics, clinical presentation and management, and short-term outcomes were compared. Results: Ninety-four patients were included in the study (37 patients in group 1 and 57 patients in group 2). A higher percentage of obese and Hispanic men was found in group 1 ( P > .05). The rate of discharge from the emergency department was significantly higher in group 1 (56.8% in group 1 vs 7.0% in group 2, P < .01). Group 2 patients had a shorter median length of stay than group 1 patients (3.1 vs 5.7 days, P = .16). There were no differences in vital signs, laboratory data (including complete blood count and basic metabolic panel), and in-hospital mortality rates between the 2 groups. Conclusions: This study demonstrates that young Hispanic men develop diverticulitis and that this diagnosis needs to be considered when they present to emergency rooms with abdominal symptoms. A longitudinal study is needed to determine the long-term outcomes in these patients and to investigate the pathogenesis.

Surgical management of colonic diverticular disease: Discrepancy between right- and left-sided diseases

AIM: To compare the outcome of the surgical management of left-sided and right-sided diverticular disease.

METHODS: The medical records of 77 patients who were surgically treated for diverticular disease between 1999 and 2010 in a tertiary referral hospital were retrospectively reviewed. The study population was limited to cases wherein the surgical specimen was confirmed as diverticulosis by pathology. Right-sided diverticula were classified as those arising from the cecum, ascending colon, and transverse colon, and those from the descending colon, sigmoid colon, and rectum were classified as left-sided diverticulosis. To assess the changing trend of occurrence of diverticulosis, data were compared with two previous studies of 51 patients.

RESULTS: The proportion of left-sided disease cases was significantly increased compared to the results of our previous studies in 1994 and 2001, (27.5% vs 48.1%, P < 0.05). Moreover, no differences in gender, body mass index, multiplicity of the diverticula, fever, or leukocytosis were noted between patients with right-sided and left-sided disease. However, patients with right-sided disease were significantly younger (50.9 year vs 64.0 year, P < 0.01). Furthermore, left-sided disease was significantly associated with a higher incidence of complicated diverticulitis (89.2% vs 57.5%, P < 0.01), combined resection due to extensive inflammation (21.6% vs 5.0%, P < 0.05), operative complications (51.4% vs 27.5%, P < 0.05), and in-hospital mortality (10.8% vs 0%, P < 0.05), along with longer post-operative hospitalization duration (21.3 ± 10.2 d vs 10.6 ± 8.1 d, P < 0.05).

CONCLUSION: Compared with right-sided diverticular disease, the incidence of left-sided disease in Korea has increased since 2001 and is associated with worse surgical outcomes.

Aspirin and non-aspirin NSAIDs increase risk of colonic diverticular bleeding: a systematic review and meta-analysis

Lower gastrointestinal bleeding is a frequent cause of hospitalization, particularly in the elderly, and its incidence appears to be on the rise. Colonic diverticular bleeding is the most common form of lower gastrointestinal bleeding and is responsible for 30-40 % of bleeding episodes. Risk factors associated with diverticular bleeding include obesity, hypertension, anticoagulants, diabetes mellitus, and ischemic heart disease. Recent studies have suggested a relationship between usage of non-steroidal anti-inflammatory drugs (NSAIDs) and colonic diverticular bleeding; however, most studies were small with wide confidence intervals. We identified studies by searching the PubMed and Scopus databases (from inception through 31 December 2012) and by searching bibliographies of relevant articles. Summary relative risks (RRs) with 95 % confidence intervals (CIs) were calculated with fixed-effects and random-effects models. A total of six studies (five case-control studies and one cohort study) met inclusion criteria for analysis. Non-aspirin NSAIDs (NANSAIDs) and aspirin were associated with an increased risk of colonic diverticular bleeding (summary RR = 2.48, 95 % CI 1.86-3.31), with moderate heterogeneity among these studies (P heterogeneity = 0.11, I (2) = 44.4 %). Stratification to evaluate the heterogeneity found that both NANSAIDs (summary RR = 2.24, 95 % CI 1.63-3.09; 5 studies) and aspirin (summary RR = 1.73; 95 % CI 1.31-2.30; 3 studies) were associated with the risk of diverticular bleeding. Aspirin/NANSAIDs use was strongly and consistently associated with an increased risk of colonic diverticular bleeding. Further studies are needed to stratify individuals at risk of diverticular bleeding associated with the use of these agents.

Position paper: management of perforated sigmoid diverticulitis

Over the last three decades, emergency surgery for perforated sigmoid diverticulitis has evolved dramatically but remains controversial. Diverticulitis is categorized as uncomplicated (amenable to outpatient treatment) versus complicated (requiring hospitalization). Patients with complicated diverticulitis undergo computerized tomography (CT) scanning and the CT findings are used categorize the severity of disease. Treatment of stage I (phlegmon with or without small abscess) and stage II (phlegmon with large abscess) diverticulitis (which includes bowel rest, intravenous antibiotics and percutaneous drainage (PCD) of the larger abscesses) has not changed much over last two decades. On the other hand, treatment of stage III (purulent peritonitis) and stage IV (feculent peritonitis) diverticulitis has evolved dramatically and remains morbid. In the 1980s a two stage procedure (1st - segmental sigmoid resection with end colostomy and 2nd - colostomy closure after three to six months) was standard of care for most general surgeons. However, it was recognized that half of these patients never had their colostomy reversed and that colostomy closure was a morbid procedure. As a result starting in the 1990s colorectal surgical specialists increasing performed a one stage primary resection anastomosis (PRA) and demonstrated similar outcomes to the two stage procedure. In the mid 2000s, the colorectal surgeons promoted this as standard of care. But unfortunately despite advances in perioperative care and their excellent surgical skills, PRA for stage III/IV diverticulitis continued to have a high mortality (10-15%). The survivors require prolonged hospital stays and often do not fully recover. Recent case series indicate that a substantial portion of the patients who previously were subjected to emergency sigmoid colectomy can be successfully treated with less invasive nonoperative management with salvage PCD and/or laparoscopic lavage and drainage. These patients experience a surprisingly lower mortality and more rapid recovery. They are also spared the need for a colostomy and do not appear to benefit from a delayed elective sigmoid colectomy. While we await the final results ongoing prospective randomized clinical trials testing these less invasive alternatives, we have proposed (based primarily on case series and our expert opinions) what we believe safe and rationale management strategy.

Persistent perforation in non-faeculant diverticular peritonitis--incidence and clinical significance

BACKGROUND

Non-resectional strategies (NRS) have improved outcomes for a sub-group of patients with perforated diverticulitis. NRS are applicable to patients with non-faeculant peritonitis (Hinchey II and III). Success is dependent on the initial perforation sealing, which Hinchey estimated occurred 'most of the time'. An exact percentage remains ill-defined.

OBJECTIVE

We aimed to define the percentage and clinical significance of a persistent perforation in non-faeculant diverticular peritonitis.

DESIGN

A retrospective review was conducted of all patients admitted with a diagnosis of perforated diverticulitis between January 1999 and July 2010. Patients undergoing an emergency operation were analysed according to Hinchey and physiological and operative severity scores and compared with histological findings.

RESULTS

One hundred fifteen patients were identified. Fifty-three patients underwent a 'resectional' procedure. At surgery, 15 patients had faeculent peritonitis, 27 patients had purulent peritonitis and 11 patients had a contained abscess. Of the patients with non-faeculant peritonitis, 2/9 (22.2 %) Hinchey II and 10/27 (37.1 %) Hinchey III patients had persistent perforation on review of histology. Persistent perforation was associated with a significant increase in morbidity, length of stay, physiological and operative severity score (p = 0.015, 0.011, 0.049 and 0.002, respectively).

CONCLUSION

A proportion of patients with non-faeculant peritonitis have a persistent perforation which is associated with a poorer outcome and is likely to result in failure of a non-resectional management strategy. Updated classification systems and tailored peri-operative investigations are required to identify this sub-group of patients and improve patient outcomes.

The role of colonic mast cells and myenteric plexitis in patients with diverticular disease

BACKGROUND

Gut mast cells represent an important cell population involved in intestinal homeostasis and inflammatory processes. However, their possible role has not to date been investigated in colonic diverticular disease.

AIMS

This study aims to evaluate colonic mast cells in patients undergoing surgery for diverticular disease.

METHODS

Surgical resection samples from 27 patients undergoing surgery for diverticular disease (12 emergency procedures for severe disease and 15 elective procedures) were evaluated. The number of mast cells was assessed in the various layers by means of a specific antibody (tryptase) and compared with those evaluated in ten controls. In patients with mast cells degranulation, double immunohistochemistry, also assessing nerve fibres, was carried out. In addition, the presence of myenteric plexitis was sought.

RESULTS

Compared with controls, the number of mast cells in diverticular patients was significantly increased, both as an overall figure and in the various layers of the large bowel. In patients in whom mast cells degranulation was present, these were always closed to nerve fibres. No differences were found between the two subgroups of patients with respect to the number and distribution of mast cells; however, all patients undergoing emergency surgery (but none of those undergoing elective procedures) had myenteric plexitis, represented by lymphocytic infiltration in 67 % and eosinophilic infiltration in 33 % of cases.

CONCLUSIONS

Patients with diverticular disease display an increase of mast cells in the large bowel. The presence of myenteric plexitis in those with complicated, severe disease, suggest that this could represent a histopathologic marker of more aggressive disease.

Diverticular disease: eat your fiber!

In industrialized nations, diverticular disease affects up to 70% of individuals by 60 years of age, with symptoms that can range from mild gastrointestinal disturbance to incapacitating pain. Diverticular disease appears to be related to increasing affluence and changed diet: Current theory holds that diverticular disease's origin is low-fiber diet. This explains why its incidence is highest and accelerating in the more prosperous countries where intake of fiber has decreased and intake of milled grains and refined sugars has increased over time. Not all patients develop symptoms, but if they do, the most frequent complaints associated with diverticulosis are cramping in the left-lower quadrant, bloating, constipation, and soiling. If diverticula perforate the gut's wall into the pericolic tissue, small and large abscesses, accompanied by bleeding, can form. Fistulization, when it occurs, most often penetrates to the bladder. Treatment addresses symptoms and may require hospitalization. During symptomatic periods, patients do best on low-fiber, bland diets. Once the acute episode or highly symptomatic period resolves or chronic disease is managed, patients should gradually increase dietary fiber to 20 to 30 grams daily or take dietary fiber in the form of bulk stimulants like psyllium.

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.

The clinical factors for predicting severe diverticulitis in Korea: a comparison with Western countries

BACKGROUND/AIMS

It is unclear whether the risk factors associated with complicated diverticulitis in Asian and Western countries are the same. We evaluated the risk factors associated with severe diverticulitis (SD) in Korea and compared the clinical characteristics of diverticulitis according to location.

METHODS

A retrospective review of 190 patients hospitalized with acute diverticulitis from January 2005 to June 2010 was conducted. SD was defined as one of the following: perforation, abscess, obstruction, sepsis, or peritonitis that required an urgent operation.

RESULTS

Twenty-four patients (12.6%) were diagnosed with SD. SD was significantly associated with older age, a fever over 38℃, changes in bowel habits and a high visceral adipose tissue (VAT)/total adipose tissue (TAT) ratio. Multivariate analysis showed that the risk factors for developing SD were an age of 40 years or more (odds ratio [OR], 3.2; p=0.032), male gender (OR, 4.0; p=0.021) and left-sided diverticulitis (OR, 6.2; p=0.017). Right-sided diverticulitis (n=175, 92.1%) was significantly associated with younger ages, fewer changes in bowel habits, fewer comorbidities and non-SD.

CONCLUSIONS

This study suggests that the risk factors for developing SD in Korea, where right-sided diverticulitis is predominant, are the male gender, an age of more than 40 years old, and left-sided diverticulitis. Given that there are different risk factors for developing SD in Western countries, different strategies for the treatment of diverticulitis in the Korean population seem to be needed.