Increased mucosal eosinophils in colonic diverticulosis and diverticular disease.

AIMS: Eosinophils contribute to tissue homeostasis, damage, and repair. The mucosa of colonic diverticula has not been evaluated for eosinophils by quantitative histology. We aimed to investigate whether mucosal eosinophils and other immune cells are increased in colonic diverticula. METHODS: Hematoxylin and eosin stained sections from colonic surgical resections (n = 82) containing diverticula were examined. Eosinophils, neutrophils, and lymphocytes, in five high power fields in the lamina propria were counted at the base, neck, and ostia of the diverticulum and counts compared to non-diverticula mucosa. The cohort was further subgrouped by elective and emergency surgical indications. RESULTS: Following an initial review of 10 surgical resections from patients with diverticulosis, a total of 82 patients with colonic resections containing diverticula from the descending colon were evaluated (median age 71.5, 42 M/40F). Eosinophil counts for the entire cohort were increased in the base and neck (median 99 and 42, both P = <0.001) compared with the control location (median 16). Eosinophil counts remained significantly increased in the diverticula base (both P = <0.001) and neck (P = 0.01 and <0.001, respectively) in both elective and emergency cases. Lymphocytes were also significantly increased at the diverticula base compared to controls in both elective and emergency subgroups. CONCLUSION: Eosinophils are significantly and most strikingly increased within the diverticulum in resected colonic diverticula. While these observations are novel, the role of eosinophil and chronic inflammation is as yet unclear in the pathophysiology of colonic diverticulosis and diverticular disease.

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.

Diverticulosis, Symptoms and Colonic Inflammation: A Population-Based Colonoscopy Study.

INTRODUCTION: Low-grade chronic inflammation has been suggested to play a role in uncomplicated asymptomatic and symptomatic diverticular disease. However, population-based studies are lacking. We investigated whether community participants with diverticulosis, with or without symptoms, would have colonic inflammation on histology and serology. METHODS: In a nested case-control study of 254 participants from the population-based colonoscopy (PopCol) study, colonic histological inflammatory markers and serological C-reactive protein levels were analyzed in cases with diverticulosis and controls without diverticulosis. Statistical methods included logistic and linear regression models. RESULTS: Background variables including age (P = 0.92), sex (P = 1.00), body mass index (P = 0.71), smoking (P = 0.34), and recent antibiotic exposure (P = 0.68) were similar between cases and controls. Cases reported more abdominal pain (P = 0.04) and diarrhea symptoms (mushy and high-frequency stools) than controls (P = 0.01 and P = 0.03, respectively) but were otherwise similar. The median C-reactive protein levels were similar among cases and controls [1.05 mg/L (0.3, 2.7) vs 0.8 (0.4, 2.2), P = 0.53]. There was a trend of increased numbers of cecal lymphoid aggregates in cases vs controls (P = 0.07), but no other associations between diverticulosis and inflammatory markers on histology were found. Similarly, no serological or mucosal inflammation was associated with symptomatic cases of diarrhea or abdominal pain vs asymptomatic controls. CONCLUSIONS: In a general community sample, both asymptomatic and symptomatic diverticulosis are not associated with colonic mucosal inflammation. Other explanations for symptomatic colonic diverticulosis need to be identified.

Impact of Computed Tomography Evaluation Before Colonoscopy for the Management of Colonic Diverticular Hemorrhage.

GOALS: The purpose of this study was to investigate and summarize our experience of a standardized strategy using computed tomography (CT) followed by colonoscopy for the assessment of colonic diverticular hemorrhage with focus on a comparison of CT and colonoscopy findings in patients with colonic diverticular hemorrhage. BACKGROUND: Colonic diverticular hemorrhage is usually diagnosed by colonoscopy, but it is difficult to identify the responsible bleeding point among many diverticula. STUDY: We retrospectively included 257 consecutive patients with colonic diverticular hemorrhage. All patients underwent a CT examination before colonoscopy. All-cause mortality and rebleeding-free rate after discharge were analyzed by Kaplan-Meier analysis and compared using the log-rank test. RESULTS: In CT examinations, 184 patients (71.6%) had definite diverticular hemorrhage with 31.9% showing intraluminal high-density fluid on plain CT, 39.7% showing extravasation, and 31.1% showing arteriovenous increase of extravasation on enhanced CT. In colonoscopy, 130 patients (50.6%) showed endoscopic stigmata of bleeding with 12.1% showing active bleeding, 17.1% showing a nonbleeding visible vessel, and 21.4% showing an adherent clot. A comparison of the locations of bleeding in CT and colonoscopy showed that the agreement rate was 67.3%, and the disagreement rate was 0.8% when the lesion was identified by both modalities patients with definite diverticular hemorrhage identified by CT had a longer hospital stay, higher incidences of hemodynamic instability and rebleeding events than did patients with presumptive diverticular hemorrhage. CONCLUSION: CT evaluation before colonoscopy can be a good option for managing patients with colonic diverticular hemorrhage.

Diverticular Perforation: A Fatal Complication to Forestall in Cushing Syndrome.

Context: Patients taking exogenous glucocorticoids are at risk for gastrointestinal (GI) complications, including peptic ulcer disease with perforation and gastric bleeding. However, little is known about the GI comorbidity in patients with endogenous hypercortisolemia. Case Descriptions: We describe six patients with endogenous Cushing syndrome (CS) who developed sudden perforation of colonic diverticula necessitating urgent exploratory laparotomy. Most of these patients shared the following features of CS: skin thinning, severe hypercortisolemia (24-hour urinary free cortisol ≥10 times the upper limit of normal), ectopic secretion of ACTH, and severe hypokalemia. At the time of diagnosis of diverticular perforation (DP), these patients had minimal signs of peritonitis and lacked fever or marked leukocytosis. The diagnosis of DP was established by having a low threshold for obtaining an imaging study for evaluation of nonspecific abdominal pain. Conclusions: Patients with CS can develop spontaneous surgical abdomen with rapid decompensation within hours. Prompt recognition is critical in the successful treatment of these patients.

Diverticular colitis with progression to ulcerative colitis after sigmoidectomy.

Diverticular colitis is chronic inflammation of the colon where diverticula are present. The endoscopic and histopathological findings of this disease are sometimes similar to those of ulcerative colitis, and several reports describe cases of diverticular colitis that progressed to typical ulcerative colitis. A 77-year-old woman with intramesenteric penetration of the sigmoid diverticulum underwent low anterior resection. One month later, the patient experienced anastomotic leakage, and transverse colostomy was performed. Six months after the colostomy, the patient returned to the hospital with complaints of bloody discharge from the rectum and stoma. Colonoscopy revealed newly developed loss of vascular pattern and a granular appearance of the mucosa in the rectum that had not been present at prior examinations. She was diagnosed with ulcerative colitis, which developed after colectomy, and treated with mesalazine and high-dose prednisolone, but the clinical and endoscopic response was poor. Finally, the patient underwent total proctocolectomy and ileal pouch anal anastomosis with diverting ileostomy. As a few reports have described, diverticular colitis can progress to typical ulcerative colitis after surgery in some cases, suggesting a possible pathogenic similarity between the two diseases and association between colorectal surgery and disease progression.

Association between endoscopic findings related to colonic diverticula and bowel habits: A multicenter study in Japan.

BACKGROUND AND AIM: Few studies have shown the associations between colonic diverticula and endoscopic findings such as location, inflammation, number of diverticula, sigmoid colon rigidity, and bowel habits. METHODS: Japanese subjects who underwent total colonoscopies at six centers in Japan from November 2015 to October 2016 were analyzed. Bowel habits were evaluated using the Gastrointestinal Symptom Rating Scale. Location and number of diverticula, inflammation, and sigmoid colon rigidity were evaluated from endoscopy results. RESULTS: A total of 762 subjects (486 men and 276 women [ratio, 1.76:1]) whose mean age was 65.5 ± 11.4 years were evaluated. In multivariate analysis, presence of constipation was associated with a significantly lower likelihood of left-sided colonic diverticula (odds ratio = 0.40, 95% confidence interval 0.20-0.82, P = 0.012), whereas right-sided and bilateral-sided colonic diverticula, multiple colonic diverticula, inflammation findings, and sigmoid colon rigidity were not related to bowel habits. CONCLUSIONS: Among endoscopic findings related to colonic diverticula and bowel habits, only left-sided colonic diverticula were inversely associated with constipation, whereas inflammation findings, multiple diverticula, and sigmoid colon rigidity were not related to bowel habits. However, the association of inflammation findings with colonic diverticula and bowel habits should be further studied. Investigation of changes in left-sided colonic diverticula may lead to new treatments for constipation.

Diverticular Disease and Colorectal Cancer: Incidental Diagnosis or Real Association? Final Answer.

Associations between diverticular disease of the colon and the colorectal cancer has been studied for >60 years. Observational, cross-sectional, and case-control studies as well as large population-based studies gave conflicting results and association was not fully proven. Obtaining the proof was difficult because both diseases share similar clinical characteristics, both increase with age, and both involve similar dietary factors. Long-term observations are difficult as diagnostic methods changed over time from barium enema 50 to 60 years ago, through endoscopy, up to CT and MR in recent years. Cancer or adenomas may be missed within diverticular segment; diverticula may be underreported in patients with colon cancer diagnosis. Most recent 2 large cohort studies have solved the dilemma. These studies have clearly shown that diverticular disease does not increase the risk of colon cancer after the first year of diagnosis. Within the first year of diagnosis the association is strong, most probably due to difficulties with differential diagnosis and misclassifications and shared symptoms. Findings of these studies have led to the conclusion that colon cancer has to be excluded using modern techniques after the first episode of suspected diverticulitis.