Distinct changes in the colonic microbiome associated with acute diverticulitis.

AIM: The pathogenesis of acute diverticulitis (AD) remains incompletely understood, despite it being one of the most common gastrointestinal conditions worldwide. The aim of this study was to investigate the role of the colonic microbiome in the pathogenesis of AD. METHOD: A prospective case-control study was performed, comparing the microbiome of AD patients with that of controls, using 16S rRNA sequencing of rectal swab samples. RESULTS: The microbiome of individuals with AD showed lower diversity than that of controls. There were significant compositional differences observed, with a lower abundance of commensal bacterial families and genera such as Lachnospiraceae, Ruminococcus and Faecalibacterium in AD patients compared with controls, and there was an increase in several genera with known pathogenic roles including Fusobacteria, Prevotella and Paraprevotella. CONCLUSION: This is the largest study to date to examine the microbiota of AD patients, and adds evidence to the proposed hypothesis that alterations in the colonic microbiome play a role in the pathogenesis of AD.

The impact of prolonged delay to loop ileostomy closure on postoperative morbidity and hospital stay: A retrospective cohort study.

AIM: There is increasing evidence that delayed loop ileostomy closure is associated with an increase in postoperative morbidity. In the context of a publicly funded health service with constrained theatre access, we review the impact of delay in loop ileostomy closure. METHOD: A retrospective cohort study of patients undergoing loop ileostomy closure at the Dunedin Public Hospital between 2000-2017 was performed. Cases and complications were identified from the prospectively maintained Otago Clinical Audit database. Patient demographics, ASA score, indications for ileostomy, reasons for delay in closure, length of stay (LOS) after ileostomy closure and complications were collected. LOS and overall complication rate were assessed using univariable and multivariable analyses. RESULTS: A total of 292 patients were included in the study, of whom 74 (25.3%) were waiting for longer than 12 months for ileostomy closure. The overall complication rate was 21.5%. This was 8% up to 90 days, 20% between 90-360 days, 28% between 360-720 days and 54% after 720 days. Delay was associated with an increased risk of any complication (RR 1.06 for every 30 days with stoma, p < 0.001), including Ileus (OR [95% CI] 1.06 [1.00-1.11], p = 0.024). Overall mean LOS was 5.9 days (range 1-63), being 4.6 days up to 180 days, 5.6 between 180-720 days and 8.7 after 720 days. LOS significantly increased with increasing stoma duration (p = 0.04). CONCLUSION: Increasing time with loop ileostomy is detrimental for patients, being associated with an increase in complication rates, and is detrimental for hospitals due to increased length of stay. Resources should be allocated for timely closure of loop ileostomies.

Acute Diverticulitis in Young Patients: A Review of the Changing Epidemiology and Etiology.

Acute diverticulitis is one of the leading gastrointestinal causes for hospitalization. The incidence of acute diverticulitis has been increasing in recent years, especially in patients under 50 years old. Historically, acute diverticulitis in younger patients was felt to represent a separate entity, being more virulent and associated with a higher rate of recurrence. Accordingly, young patients were often managed differently to older counterparts. Our understanding of the natural history of this condition has evolved, and current clinical practice guidelines suggest age should not alter management. The purpose of this review is to evaluate the changing epidemiology of acute diverticulitis, consider potential explanations for the observed increased incidence in younger patients, as well as review the natural history of acute diverticulitis in the younger population.

The Epidemiology and Etiology of Right-Sided Colonic Diverticulosis: A Review.

Diverticulosis of the colon is a common condition in Western countries and most patients will remain asymptomatic, but some will present with symptoms of acute diverticulitis or bleeding. Our understanding of diverticulosis is evolving but is mostly derived from diverticulosis affecting the left-sided colon. In contrast, right-sided colonic diverticulosis (RCD) is more commonly seen in Asian countries but is much less common overall. Based on the marked differences in epidemiology, it is commonly thought that these are 2 distinct disease processes. A review of the literature describing the epidemiology and etiology of RCD was performed, with a comparison to the current understanding of left-sided diverticulosis. RCD is becoming increasingly common. The epidemiology of RCD shows it to be a mostly acquired condition, and not congenital as previously thought. Many factors in the etiology of RCD are similar to that seen in left-sided diverticulosis, with a few variations. It is therefore likely that most cases of RCD represent the same disease process that is seen in the left colon.

The prevalence of right-sided colonic diverticulosis in a New Zealand population.

BACKGROUND: Once considered to be a congenital condition, the epidemiology of right-sided colonic diverticulosis (RCD) is evolving. Acute diverticulitis (AD) is a complication of RCD which is frequently misdiagnosed as appendicitis, resulting in unnecessary surgery, as there is strong evidence supporting medical management for right-sided AD. In general, the incidence of AD correlates with the prevalence of RCD, which shows marked geographic variation. Few data reporting RCD prevalence come from Western countries, so the aim of this study is to define the prevalence of RCD in a New Zealand population. METHODS: Independent review of the imaging from 1000 consecutive patients undergoing a computed tomography Kidney/Ureter/Bladder scan for suspected urolithiasis at Christchurch Hospital between January and November 2017 was undertaken, to determine the presence or absence, and distribution of colonic diverticulosis. Patients were excluded if they had a history of colonic resection, known IBD, or were less than 18-years old. RESULTS: Thirty-one patients were excluded, leaving 969 eligible patients. Overall, 95 patients (9.8%) had RCD identified. The prevalence of RCD increased significantly with advancing age, being present in 2.3% of those aged 18-29, increasing to 20.3% in those greater than 70-years old (p < 0.001). CONCLUSION: The prevalence of RCD in a New Zealand population is relatively high and increases significantly with age. This adds support to the role of cross-sectional imaging in the evaluation of suspected appendicitis, to exclude right-sided AD. The association with advancing age supports RCD being an acquired condition rather than a congenital condition as was previously thought.

Influence of obesity on the risk of recurrent acute diverticulitis.

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

Endoscopic large balloon sphincteroplasty is a useful, safe adjunct for difficult to treat choledocholithiasis.

BACKGROUND: The aim of this study was to assess the safety and efficacy of large balloon sphincteroplasty when used in conjunction with endoscopic biliary sphincterotomy during endoscopic retrograde cholangiopancreatography (ERCP) for therapy of choledocholithiasis. METHODS: A retrospective audit of all ERCP's performed for choledocholithiasis between January 2012 and October 2013 at one institution was performed. Procedures that utilized large balloon sphincteroplasty were compared with those underwent standard endoscopic stone extraction. Outcomes including stone clearance rate for the individual procedure type, post-ERCP complications and need for surgical exploration of the bile duct were documented. RESULTS: A total of 346 procedures on 306 patients that met the inclusion criteria were identified. Fifty-four (15.6%) procedures included large balloon sphincteroplasty and were compared with 292 (84.4%) procedures that used standard balloon extraction techniques. Despite those patients in the large balloon sphincteroplasty group having a higher rate of previous ERCP (33.3% versus 19.5%, P = 0.031) and a larger proportion of patients with stones greater than 10 mm (40.3% versus 11.3%, P < 0.001), the overall initial clearance rate was similar at 83%. Ultimately, only 14 out of 306 (4.6%) of all patients required surgical intervention. There was no significant difference in the rate of post-ERCP pancreatitis between the two groups (5.6% versus 3.8%, P = 0.466). CONCLUSION: Large balloon sphincteroplasty of the sphincter of Oddi is a safe and effective adjunct to endoscopic biliary sphincterotomy in difficult to treat choledocholithiasis. The current study demonstrated large balloon sphincteroplasty did not result in more complications despite a tendency to being used for larger stones.

Cystoprostatectomy versus prostatectomy alone for locally advanced or recurrent pelvic cancer.

BACKGROUND: There is minimal published data evaluating the oncological outcome of rectal resection with prostatectomy alone versus rectal resection with cystoprostatectomy in patients undergoing pelvic exenteration for locally advanced or recurrent pelvic cancer. This study aims to evaluate the oncological and functional outcomes of performing rectal resection with prostatectomy alone compared with rectal resection with cystoprostatectomy in patients undergoing pelvic exenteration. METHODS: Consecutive patients undergoing pelvic exenteration for locally advanced or recurrent pelvic cancer between 1998 and 2012 were identified from a prospectively maintained database. Patients undergoing rectal resection with prostatectomy alone were compared with a control group who underwent rectal resection with cystoprostatectomy and urostomy formation. The primary outcome was overall survival. Secondary outcomes analysed in the prostatectomy group included completeness of resection, continence and erectile function. RESULTS: Eleven rectal resections with prostatectomy were compared with 20 rectal resections with cystoprostatectomy. R0 resection was achieved in 73 and 65% respectively. There was no difference in overall survival (P = 0.40). Urinary continence was achieved in 36% of prostatectomy alone patients, while 27% experienced mild incontinence. Erectile function was poor, with only one patient able to maintain normal erections. CONCLUSION: In appropriately selected patients with invasive pelvic tumours, rectal resection with prostatectomy alone provides adequate oncological outcomes. The ability to achieve an R0 resection was not compromised and overall survival is comparable with cystoprostatectomy. Urinary function is reasonable in most patients, although sexual function is compromised in almost all.