Appendiceal orifice inflammation is associated with proximal extension of disease in patients with ulcerative colitis

A Comprehensive Multidisciplinary Approach to Diagnosing Chronic Inflammatory Bowel Diseases: Integration of Clinical, Endoscopic, and Imaging Modalities

Chronic inflammatory bowel diseases, such as Crohn's disease and ulcerative colitis, present diagnostic challenges due to their complex and heterogeneous nature. While histology remains fundamental for accurate diagnosis, a multidisciplinary approach incorporating clinical, endoscopic, and imaging modalities is increasingly recognized as essential for comprehensive evaluation. This article delves into the importance of integrating various diagnostic techniques in the assessment of IBD. Colonoscopy and histology, with its ability to directly visualize the intestinal mucosa, play a central role in the diagnostic process. However, histological analysis alone may not suffice, necessitating the inclusion of advanced imaging techniques, such as magnetic resonance enterography (MRE), computed tomography enterography (CTE), and intestinal ultrasound (IUS). These techniques provide valuable insights into the disease's extent, severity, and complications, and should be used in conjunction with biochemical parameters. These modalities complement traditional endoscopic and histological findings, offering a more holistic understanding of the disease process. A multidisciplinary approach that incorporates clinical, endoscopic, histological, serological, and imaging assessments enables clinicians to achieve a more accurate and timely diagnosis of IBD. Moreover, this integrated approach facilitates personalized treatment strategies tailored to individual patient needs, ultimately improving clinical outcomes and quality of life for those affected by chronic inflammatory bowel diseases.

Ulcerative colitis

Ulcerative colitis is a lifelong inflammatory disease affecting the rectum and colon to a variable extent. In 2023, the prevalence of ulcerative colitis was estimated to be 5 million cases around the world, and the incidence is increasing worldwide. Ulcerative colitis is thought to occur in people with a genetic predisposition following environmental exposures; gut epithelial barrier defects, the microbiota, and a dysregulated immune response are strongly implicated. Patients usually present with bloody diarrhoea, and the diagnosis is based on a combination of clinical, biological, endoscopic, and histological findings. The aim of medical management is, first, to induce a rapid clinical response and normalise biomarkers and, second, to maintain clinical remission and reach endoscopic normalisation to prevent long-term disability. Treatments for inducing remission include 5-aminosalicylic acid drugs and corticosteroids. Maintenance treatments include 5-aminosalicylic acid drugs, thiopurines, biologics (eg, anti-cytokines and anti-integrins), and small molecules (Janus kinase inhibitors and sphingosine-1-phosphate receptor modulators). Although the therapeutic options are expanding, 10-20% of patients still require proctocolectomy for medically refractory disease. The keys to breaking through this therapeutic ceiling might be the combination of therapeutics with precision and personalised medicine.

Advances in Endoscopy for Pediatric Inflammatory Bowel Disease

Endoscopic characterization of pediatric inflammatory bowel disease (IBD) has developed in accordance with advances in treatment and improved understanding of disease progression and complications. Reliable and consistent endoscopic reporting practices and tools continue to evolve. The roles of endoscopic ultrasonography, capsule endoscopy, and deep enteroscopy in the care of children and adolescents with IBD are beginning to be clarified. Opportunities for therapeutic intervention with endoscopy in pediatric IBD, including endoscopic balloon dilation and electroincision therapy, require further study. This review discusses the current utility of endoscopic assessment in Pediatric Inflammatory Bowel Disease, as well as emerging and evolving techniques to improve patient care.

Clinical significance and long-term prognosis of ulcerative colitis patients with appendiceal orifice inflammation

BACKGROUND

Appendiceal orifice inflammation (AOI) or peri-appendiceal red patch is a skip lesion with segments of continuous colitis from the rectum. Frequently observed in ulcerative colitis (UC) patients, this lesion might be associated with proximal extension in some studies. However, the clinical significance of this lesion and long-term outcomes including therapy remain unclear. Thus, the aim of this study was to evaluate the clinical implication of AOI during long-term periods in patients with UC.

METHODS

We retrospectively reviewed 376 patients with UC who performed complete colonoscopic examinations between April 2000 and December 2020. We compared clinical characteristics and outcomes of patients manifesting AOI with those who did not show AOI during a mean follow-up period of 66.1 months. Long-term outcomes included maximal extent of colitis, proximal extension, therapeutic medical histories, UC-related hospitalization, and relapse.

RESULTS

Ninety-eight (26.1%) patients showed AOI without evidence of inflammation in the right colon. Mild disease activity at the diagnosis of UC was more included in patients with AOI than in those without AOI. Other baseline characteristics including disease extent, smoking history, external intestinal manifestation, and terminal ileal ulceration were not significantly different between the two groups. During follow-up periods, patients with and without AOI showed no significant difference in proximal extension, Mayo endoscopic score at the last endoscopic examination, UC-related hospitalization, or relapse. Of medication history, patients with AOI were less included in the group treated with high-dose aminosalicylates than those without AOI. However, therapeutic histories of steroids, immunosuppressive agents, and biologics were not significantly different. Of 62 patients with AOI who underwent follow-up colonoscopy, 36 (58.1%) showed resolution of AOI. Clinical outcomes of the resolution group were not different than those of the non-resolution group. Biopsy results of 77 patients with AOI showed chronic active or erosive colitis.

CONCLUSIONS

Long-term outcomes of UC patients with AOI were not different from those without AOI. Outcomes of resolution and non-resolution groups of AOI patients were not different either. Thus, AOI might have no prognostic implication in distal UC patients.

Significance of diagnosis and prognosis for appendiceal orifice inflammation in ulcerative colitis: a real-world study

OBJECTIVE

Ulcerative colitis (UC) is a chronic inflammatory disease of the large intestine. At present, the significance of appendiceal orifice inflammation (AOI) in UC prognosis is still controversial. This prospective observational study investigated the importance of AOI in UC diagnosis and prognosis. Additionally, it compared the therapeutic efficacy of treatments in UC patients with or without AOI.

DESIGN

This study was a prospective, observational, single-centre, real-world study. Patients with AOI were included in the observation group, and patients without AOI were assigned to the control group. All patients were followed up for 1 year; the disease remission and treatment efficacy were re-examined by colonoscopy. In addition, the clinical, endoscopic and pathological features were collected before and after the treatment.

RESULTS

Patients with endoscopic diffuse inflammatory changes in the distal colorectum accompanied by AOI had a higher positive UC diagnosis rate than those without (96.5% vs 78.0%). Also, AOI had a specificity of 95.2% and a sensitivity of 28.3% for UC diagnosis. However, no difference in the modified Mayo score (p=0.881) or Baron grading was observed between the control and observation groups, indicating that AOI does not affect the treatment outcome of UC patients.

CONCLUSION

In this study, the observation of AOI improved the UC diagnostic accuracy in patients with diffuse lesions in the distal colorectum. Furthermore, the presence of AOI does not affect the treatment efficacies of UC.

TRIAL REGISTRATION NUMBER

ChiCTR1800017753.

Characteristics and Outcomes of Left-sided Ulcerative Colitis With a Cecal/Periappendiceal Patch of Inflammation

Ulcerative colitis (UC) is characterized by continuous mucosal inflammation of the rectum, extending uninterrupted to a variable portion of the colon proximally. However, in some patients with distal colitis, a distinct pattern of skip inflammation (so-called patch) involves the cecum and/or appendiceal orifice, but data on this entity are contradictory, and its significance and prognosis are still debated. We identified 102 adult cases of left-sided UC with a cecal/periappendiceal patch and compared them to 102 controls (left-sided UC only) along clinicopathologic characteristics and disease outcomes. In multivariate analysis, patients with a patch were younger (median age: 31 vs. 41 y; P =0.004) and more likely to have rectosigmoid involvement only (58.8% vs. 28.4%; P <0.001), compared with patients without a patch. During follow-up, patients with a patch were more likely to be eventually diagnosed with Crohn disease (CD) (9.8% vs. 1.0%; P =0.022) and to show proximal extension of inflammation (35.6% vs. 10.0%; P =0.021), but showed no differences in rates of neoplasia, colectomy, or pharmacotherapy escalation. Kaplan-Meier analysis confirmed that patients with a biopsy diagnosis of cecal/periappendiceal patch were more likely to show proximal disease extension ( P <0.001) and to be diagnosed with CD ( P =0.008). In conclusion, cecal/periappendiceal skip inflammation in left-sided UC occurs more often in younger patients and in those with rectosigmoid involvement and is associated with proximal disease extension and, in a small fraction of cases, change of diagnosis to CD. However, it does not portend increased risk of neoplasia, pharmacotherapy escalation, or subsequent colectomy, compared with patients with left-sided UC only.

Clinical relevance of endoscopic peri-appendiceal red patch in ulcerative colitis patients

BACKGROUND

Increasing evidence is suggesting appendectomy as an alternative treatment for ulcerative colitis (UC), especially in case of histological appendiceal inflammation. Therefore, preoperative identification of appendiceal inflammation could be beneficial. This study aimed to assess the prevalence of peri-appendiceal red patch (PARP) on colonoscopy. In addition, prognostic relevance of PARP for disease course and its predictive value for histological appendiceal inflammation in patients undergoing appendectomy was assessed.

METHODS

UC patients undergoing colonoscopy in 2014/2015 were included to determine PARP-prevalence in a cross-sectional study. Findings were correlated to patient and disease characteristics, upscaling of treatment and colectomy rates after cross-sectional colonoscopy. In patients undergoing appendiceal resection, histopathological inflammation was assessed using the Robarts Histopathology Index (RHI).

RESULTS

In total, 249 patients were included of which 17.7% (44/249) had a PARP. Patients with PARP were significantly younger with a shorter disease course. The majority of patients with PARP (61.4%) was in endoscopic remission. Patients with PARP required more upscaling of medical therapy (81.8% vs. 58.0%, p < 0.01), and more PARP patients underwent colectomy (13.6% vs. 4.9%, p = 0.04). Patients with PARP had a higher median RHI in resection specimens (14 vs. 7, p < 0.01).

CONCLUSION

PARP was present during colonoscopy regardless disease activity and was predominantly found in UC patients with younger age and shorter disease duration. PARP patients had a more severe course of UC, and in case of appendectomy, more severe histopathological appendiceal inflammation. Appendectomy as an experimental therapy for UC has been suggested to be predominantly effective in UC patients with appendiceal inflammation. This study demonstrates that presence of a PARP on colonoscopy predicts appendiceal inflammation. After consensus has been reached on the therapeutic effect of appendectomy, assessing PARP presence during colonoscopy could therefore contribute to identifying patients most likely to respond.

Appendix and Ulcerative Colitis: a Key to Explaining the Pathogenesis and Directing Novel Therapies?

The vermiform appendix is generally considered a redundant organ, but recent evidence suggests that the appendix could contribute to the pathogenesis of inflammatory bowel diseases, in particular ulcerative colitis (UC), and may even have a therapeutic role; however, mechanisms of the appendix involvement remain unclear. Here, we highlight current evidence on the link between the appendix and UC and consider plausible therapeutic implications. A literature search was conducted using PubMed and PubMed Central from inception to Nov 2021 using the terms "Appendix", "UC", "Appendix & UC," "Appendectomy", and "Peri-appendicular patch," including only articles published in English. Reference lists from the selected studies were manually searched and reviewed to gather additional related reports. Inflammation around the appendix ("peri-appendicular patch") has been frequently observed in UC patients without other cecal involvement, and this inflammation can even precede the onset of UC. Epidemiologic studies propose that appendectomy reduces the risk of developing UC or even the risk of flare after UC is diagnosed, although this remains controversial. We reviewed studies showing altered host-microbe interactions in the appendix in UC, which suggest that the appendix could act as a priming site for disease via alterations in the immune response and changes in microbiota carried distally to the colon. In summary, recent literature suggests a possible role for microbes and immune cells within the appendix; however, the role of the appendix in the pathogenesis of UC remains unclear. Further research could clarify the therapeutic potential related to this organ.

Appendiceal Orifice Inflammation Is Associated with Lower Rate of Complete Endoscopic Remission in Patients with Ulcerative Colitis

Appendiceal orifice inflammation (AOI) is commonly considered a skip lesion in ulcerative colitis (UC). However, the clinical significance of AOI in UC patients remains controversial. This study aimed to evaluate the clinical feature and long-term outcomes of AOI by comparing UC patients with and without AOI. This study was conducted as a retrospective design of patients who were newly diagnosed or referred within 3 months after diagnosis at Seoul St. Mary's Hospital from 1 January 2001 to 31 December 2020. All patients underwent index and follow-up colonoscopies. The long-term outcomes involved achieving complete endoscopic remission (ER), use of biologics, hospitalization, and proximal disease extension. Complete ER was defined as Mayo endoscopic subscore 0. In total, 318 UC patients were included, of which 140 had AOI. The baseline characteristics were not significantly different between AOI and non-AOI groups. The cumulative risk of complete ER was a significant difference between AOI and non-AOI groups (p = 0.041). The other cumulative risks of disease outcomes were not significantly different between AOI and non-AOI groups (use of biologics, p = 0.542; hospitalization, p = 0.795; proximal disease extension, p = 0.403). The multivariate Cox regression analysis also revealed that AOI was the significant factor of complete ER (hazard ratio, 0.656; 95% confidence interval, 0.462-0.932; p = 0.019) in UC patients. AOI shows a significant association with lower rate of complete ER in UC patients. Therefore, a meticulous treatment strategy may be recommended to achieve complete ER in UC patients with AOI.

Baseline Histological Findings Do Not Predict the Risk of Subsequent Extension in Patients with Limited Ulcerative Colitis

BACKGROUND

Among patients with limited ulcerative colitis (UC), 30% ultimately extend to pancolitis and are at increased risk of adverse clinical outcomes. Risk of endoscopic extension has been found to correlate with clinical features such as early age of onset.

AIMS

We sought to determine whether histologic features correlate with disease extension.

METHODS

The study population consisted of 40 patients with UC from two large academic centers diagnosed between 2006 and 2017. Eligible cases had a diagnosis of endoscopically limited UC (Montreal E1 or E2) at baseline and ≥ 2 subsequent endoscopic examinations with biopsies. Severity of inflammation was scored using both the Mount Sinai Activity Index and Nancy Histological Index.

RESULTS

Patients were divided into two cohorts: those who progressed to pancolitis (Montreal E3) were defined as "Extenders" (n = 21), whereas "Non-extenders" (n = 19) were cases without progression in the follow-up period. The median follow-up time was 58.4 months. The histologic scores in the endoscopically involved mucosa of the index biopsies were not associated with subsequent extension of disease, overall. However, among extender cohort, the index histology scores correlated with biopsy scores at extension (r = 0.455, P = 0.044) and index severity was associated with a shorter time to extension (r =  - 0.611, P = 0.003). Furthermore, female patients had a shorter time to extension (P = 0.013).

CONCLUSIONS

Histological severity of limited UC is not an independent predictor of extension in UC. However, among patients who subsequently extend, severe inflammation at baseline correlates with shorter progression time and severe inflammation when extension occurs. Patients with limited UC but severe histologic inflammation may warrant more frequent endoscopic surveillance.

Irisin attenuates inflammation in a mouse model of ulcerative colitis by altering the intestinal microbiota

Evidence has demonstrated that the gut microbiota, which consists of probiotics and pathogenic microorganisms, is involved in the initiation of ulcerative colitis (UC) via the dysregulation of intestinal microflora and normal immune interactions, which ultimately leads to intestinal mucosal dysfunction. Irisin is released from muscle cells and displays anti-inflammatory effects; however, the mechanisms underlying irisin-mediated anti-inflammatory effects in UC have not been previously reported. In the present study, mice were divided into the following four groups: i) Control; ii) irisin; iii) dextran sulfate sodium (DSS) salt; and iv) DSS + irisin. Subsequently, the effects of irisin were investigated by observing alterations in intestinal microbes. Irisin significantly reduced the degree of inflammation in UC by reversing alterations to the macroscopic score, histological score, number of CD64⁺ cells and inflammatory cytokine alterations (P<0.05). Analysis of the microbial diversity in the stools of mice with active UC indicated that the five bacteria that displayed the greatest alterations in relative abundance were Alloprevotella, Bacteroides, Lachnospiraceae-UCG-001, Prebotellaceae-UCG-001 and Rikenellaceae-RCB-gut-group. Furthermore, Bactoroides were positively correlated with the histopathological score (P=0.001; R=0.977) and interleukin (IL)-23 levels (P=0.008; R=0.924). Alloprevotella (P=0.001; R=-0.943), Lachnospiraceae-UCG-001 (P=0.000; R=-0.973) and Rikenollaceae-RC8-gut-group (P=0.001; R=-0.971) were negatively correlated with the histopathological score. Furthermore, Lachnospiraceae-UCG-001 (P=0.01; R=-0.873) and Rikenollaceae-RC8-gut-group (P=0.049; R=-0.814) were negatively correlated with IL-23 levels. In summary, the results of the present study suggested that irisin improved inflammation in a UC mouse model potentially via altering the gut microbiota.

Appendiceal Orifice Inflammation in Severe Ulcerative Colitis and Its Resolution With Infliximab and Plant-based Diet as First-line Therapy

Appendiceal orifice inflammation, which is often observed in mild or moderate distal ulcerative colitis, was observed in a case of severe UC. Appendiceal orifice inflammation resolved after new induction therapy for severe UC: infliximab and a plant-based diet as first-line therapy.

Early course of newly diagnosed moderate-to-severe ulcerative colitis in Korea: Results from a hospital-based inception cohort study (MOSAIK)

BACKGROUND AND AIM

No inception cohort study has ever evaluated the early course of moderate-to-severe ulcerative colitis (UC) within 1 year of diagnosis in the non-Caucasian population. We aimed to investigate the early clinical course of moderate-to-severe UC patients in terms of remission, relapse, UC-related hospitalizations, colectomy, mortality, and overall use of medications.

METHODS

In the MOSAIK inception cohort, which is an ongoing multicenter, prospective, hospital-based, observational cohort, 354 patients with moderate-to-severe UC were followed up for 1 year. Main outcomes of UC and predictive factors for medication use over the course of 1 year were evaluated.

RESULT

Among 354 patients, 276 (78.0%) patients were followed up for 1 year. The rates of remission, relapse, UC-related hospitalizations, and proximal disease extension were 95.3%, 39.6%, 15.2%, and 12.3%, respectively. Systemic corticosteroids, thiopurines, and biologics were administered to 61.2%, 30.4%, and 10.5% of patients, respectively, throughout 1 year. One year after, 58.2% patients experienced remission or mild endoscopic activity. Overall disease courses did not show much difference according to moderate or severe disease activity at baseline. In addition, no colectomy and mortality were observed for 1 year. Predictive factors for medication use included disease severity, disease extent, endoscopic severity, and presence of periappendiceal inflammation at baseline for corticosteroid, disease extent and initial corticosteroid use for thiopurine, and only initial corticosteroid use for biologics.

CONCLUSION

Korean patients with moderate-to-severe UC may have more favorable early outcomes than Western patients. However, outcomes of them need to be further looked into for a longer time.

Clinical Significance of Residual Nonrectal Inflammation in Ulcerative Colitis Patients in Clinical Remission

Background/Aims

The treatment goal of ulcerative colitis (UC) has been changed to achieve endoscopic remission (ER). However, there is insufficient clinical evidence to determine whether a step-up treatment should be performed to achieve ER in clinical remission (CR) without ER, and there are inadequate data on the need to consider the distribution and severity of residual inflammation. This retrospective study aimed to evaluate the prognostic significance of the distribution and severity of residual inflammation in UC patients in CR.

Methods

A total of 131 UC patients in CR who underwent endoscopic evaluation for more than three times between January 2000 and December 2018 were reviewed. The patients were allocated by the endoscopic healing state and the distribution of inflammation to ER (n=31, 23.7%), residual nonrectal inflammation with patchy distribution (NRI) (n=17, 13.0%) or residual rectal involvement with continuous or patchy distribution (RI) (n=83, 63.3%) groups. We reviewed clinical characteristics, endoscopic findings, and factors associated with poor outcome-free survival (PFS).

Results

In UC patients in CR, PFS was significantly higher in the ER and NRI groups than in the RI group (p=0.003). Patients in the ER and NRI groups had similar PFS (p=0.647). Cox proportional hazard model showed only RI (hazard ratio, 5.76; p=0.027) was associated with a higher risk of poor outcome.

Conclusions

We suggest that escalation of treatment modalities may be selectively performed in consideration of the residual mucosal inflammation pattern, even if ER has not been achieved, in UC patients with CR. (Gut Liver 2021;15-409)

Prognostic Value of Terminal Ileal Inflammation in Patients with Ulcerative Colitis

Background/Aims

Few studies have investigated terminal ileal lesions and their prognostic value in patients with ulcerative colitis (UC). We evaluated the clinical significance of these lesions as a prognostic factor in patients with UC who were in clinical remission.

Methods

We retrospectively selected 567 of 4,066 colonoscopy reports that included positive findings from orificial observations of the terminal ileum (TI) and appendix in patients with UC. We finally recruited patients who were in clinical remission (n=204). We compared the clinical courses, including relapse and other prognostic parameters associated with UC, between the groups.

Results

The baseline patient characteristics were not significantly different between patients with (n=69, TI+ group) and without TI lesions (n=135, TI- group), although there were more never-smokers in the TI+ group (n=57 [82.6%] in the TI+ group; n=86 [63.7%] in the TI- group; p=0.005). Of note, appendiceal orifice inflammation (AOI) was less frequently found in the TI+ group (14.5%) than in the TI- group (71.9%, p<0.001). The cumulative relapse rate was numerically higher in the TI- group, but it was not significantly different according to the Kaplan-Meier analysis (p=0.116). Multivariate Cox regression analysis also revealed advanced age at diagnosis as the most significant factor (adjusted hazard ratio, 0.964; 95% confidence interval, 0.932 to 0.998; p=0.037), but neither TI inflammation nor AOI were significantly associated with the cumulative relapse rate in patients with UC in clinical remission.

Conclusions

For patients with UC in clinical remission, neither terminal ileal lesions nor AOI had significant clinical or predictive value for future relapse.

Appendiceal Orifice Inflammation in Ulcerative Colitis Mimicking Mucosa-Associated Lymphoid Tissue Lymphoma in the Cecum

A 55-year-old Japanese woman, who had been diagnosed with ulcerative colitis at 18 years of age, underwent screening endoscopy examinations. Esophagogastroduodenoscopy revealed an extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) of the stomach. Colonoscopy showed a slightly elevated reddish lesion with dilated microvessels but no erosions or ulcers. Although MALT lymphoma in the cecum was endoscopically suspected, flow cytometry and pathological analyses led to the diagnosis of appendiceal orifice inflammation in ulcerative colitis. This case highlights the diversity of the endoscopic appearance of appendiceal orifice inflammation in ulcerative colitis.

Endoscopic progression of ulcerative proctitis to proximal disease. Can we identify predictors of progression?

INTRODUCTION

Ulcerative proctitis is a type of ulcerative colitis circumscribed to the rectum. Proximal progression rates of the disease have been reported as between 27% and 54%. Several predictive factors have been identified for its progression; however, none has been established as definitive.

MATERIAL AND METHODS

Retrospective study of patients diagnosed with ulcerative proctitis with at least 12 months of follow-up. Patients diagnosed between January 1992 and March 2017. Variables were collected at the time of diagnosis and during the first year of follow-up. The extent of the progression was evaluated endoscopically during follow-up. The endoscopic progression rate was determined and possible risk factors related to this progression were evaluated.

RESULTS

The analysis involved 137 patients. In 77 of the patients, we performed a second colonoscopy during follow-up to evaluate endoscopic progression. The average time before the second colonoscopy performed was 5 years (SD 3.9). Of the 77 patients, 32 (41.6%) presented proximal progression to the rectosigmoid junction. Logistic regression analysis showed a statistically significant association for progression in patients who had suffered one or more flares in the first year following diagnosis. Significant progression was also observed in those with the longest time of progression at the final colonoscopy.

CONCLUSIONS

Ulcerative proctitis is not a stable disease over time. In addition, during the first year of the disease progression, it is possible to predict in which patients the disease will progress to more extensive forms.

Rectal Lymphoid Follicle Aphthous Lesions Frequently Progress to Ulcerative Colitis with Proximal Extension

Objective Rectal lymphoid follicular aphthous (LFA) lesions are related to ulcerative colitis (UC) and can be initial lesions of UC. We investigated the clinical course and prognosis of rectal LFA lesions. Methods This is a retrospective analysis of the clinical records at a single center. Patients Thirteen consecutive cases with LFA lesions treated at Hiroshima University Hospital between 1998 and 2015 were evaluated. Another 49 consecutive cases with ulcerative proctitis treated in the same period were enrolled as the control group. The clinical course and prognosis of both groups were evaluated. Results The group with LFA lesions included 9 women and 4 men with a median age of 39.9 years (range, 21-70 years). A total of 11 cases progressed to typical UC at 5-51 months. Proximal extension of these typical UC lesions was observed in 7 (53.8%) cases, which was significantly higher than in the control group (10 cases, 20.8%). Three cases (5-year accumulation incidence rate, 27.3%) progressed to steroid-intractable UC, a significantly higher incidence than that of the control group (3 cases; 5-year accumulation incidence rate, 6.9%). Conclusion Rectal LFA lesions frequently progress to typical UC with proximal extension, some of which become intractable to corticosteroid treatment.

M10, a novel derivative of Myricetin, prevents ulcerative colitis and colorectal tumor through attenuating robust endoplasmic reticulum stress

Chronic gut inflammation disposes to an increased risk of colitis-associated cancer. Chemoprevention is an attractive complementary strategy. We aimed to evaluate the chemopreventive effects of M10, a novel derivative of Myricetin, in the murine azoxymethane/dextran sodium sulfate model. Oral administration of M10 at 50-100 mg/kg once a day for consecutive 12 weeks significantly prevented ulcerative colitis (UC) and colorectal tumor. Pathological analysis of intestines showed that M10 reduced the degree of chronic inflammation and prevented the progression of colorectal tumorigenesis. Flow cytometry analysis of the immunocytes isolated from intraepithelial and lamina propria showed that M10 prevented the infiltration of myeloid-derived suppressor cells and increased CD8+T and CD4+T cells in colorectal tissues. Enzyme-linked immunosorbent analysis revealed the reduction of pro-inflammatory mediators granulocyte-macrophage colony-stimulating factor/macrophage colony-stimulating factor, IL-6 and TNF-α in colonic mucosa. Western blot assay also showed M10 prevention of the NF-κB/IL-6/STAT3 pathways and the biomarkers of inflammation and colorectal tumorigenesis. Electron microscopy analysis revealed that M10 prevent robust endoplasmic reticulum (ER) stress-induced autophagy in inflamed colonic mucosal cells. In conclusion, oral administration of Myricetin derivative M10 exerts chemoprevention of UC and colorectal tumor in mice. The mechanism of chemoprevention is associated with the reduction of biomarkers of chronic inflammation and proliferation through attenuating robust ER stress in inflamed colonic mucosal cells. M10 exerts chemoprevention activity without evidence of toxicity in mice. These results justify further evaluation of M10 in clinical trials. M10 could develop a promising regimen in the chemoprevention of colitis and colorectal cancer.

Metformin inhibited colitis and colitis-associated cancer (CAC) through protecting mitochondrial structures of colorectal epithelial cells in mice

Although a mountain of papers have showed that metformin plays a role in inhibiting cancers, but the mechanism underpinning this has not yet fully elucidated. Herein, we used AOM/DSS model, the clinicopathological features are similar to those found in humans, to investigate the effects of metformin as well as combination with 5-FU in the prevention of colitis and colitis associated cancer (CAC). Oral metformin significantly inhibited DSS-induced ulcerative colitis and AOM/DSS-induced CAC. Metformin also ameliorated 5-FU-induced colorectal gastrointestinal symptoms in mice. Metformin combination with 5-FU strongly inhibited colorectal cancer. Metformin reduced levels of the NFκB signaling components p-IKKα/β, p-NFκB, p-IκBα in colorectal mucosal cells. Transmission electron microscopy analysis suggested that the inhibition of metformin on colitis and CAC might associate with its biological activity of protecting mitochondrial structures of colorectal epithelial cells. Further analysis by Mito Tracker Red staining assay indicated that metformin prevented H₂O₂-induced mitochondrial fission correlated with a decrease of mitochondrial perimeter. In addition, metformin increased the level of NDUFA9, a Q-module subunit required for complex I assembly, in colorectal epithelial cells. These observations of metformin in the inhibition of colitis and CAC might associate with its activity of activating the LKB1/AMPK pathway in colorectal epithelial cells. In conclusion, metformin inhibited colitis and CAC through protecting the mitochondrial structures of colorectal epithelial cells.

Efficacy of topical 5-aminosalicylate monotherapy in patients with ulcerative proctitis with skip inflammation

BACKGROUND AND AIM

In some patients with ulcerative proctitis (UP), skip inflammation is noted in the right side of the colon, but little is known about its clinical course. The aim of this study was to evaluate the clinical course of UP with skip inflammation and the efficacy of topical 5-aminosalicylate (5-ASA) monotherapy.

METHODS

This study reviewed the data of 388 patients with an initial diagnosis of UP from January 2005 to October 2015. This study matched each UP patient with skip inflammation 1:2 with controls who had UP without skip inflammation; to reduce bias, this study matched the controls with the cases by age, gender, and initial disease activity.

RESULTS

During the follow-up period (median: 69.5 months), the overall progression rates for the control group (n = 192) and the skip inflammation group (n = 96) were 24.0% and 32.9% at 10 years, respectively (log-rank P = 0.71). In the skip inflammation group, the progression rates were not significantly different between the 5-ASA combination group and the topical group, 33.4% and 26.6% at 10 years, respectively (log-rank P = 0.96). The overall acute exacerbation rates for the control and skip inflammation groups were 17.2% and 26.8% at 10 years, respectively (log-rank P = 0.68). In the skip inflammation group, the exacerbation rates were also not significantly different between the combination and topical treatment groups, 26.6% and 23.6% at 10 years, respectively (log-rank P = 0.88).

CONCLUSION

The clinical course of UP with skip inflammation was not different from that of typical UP, and topical 5-ASA monotherapy for maintaining remission was as effective as 5-ASA combination therapy irrespective of the presence of skip lesions.

Clinical Predictors and Natural History of Disease Extension in Patients with Ulcerative Proctitis

BACKGROUND

A proportion of patients with initial presentation of ulcerative proctitis (UP) progress to more extensive colitis. We sought to characterize the natural history and identify clinical predictors of extension in UP.

METHODS

We performed a retrospective cohort study of participants with a new diagnosis of UP from January 2000 to December 2015. We used Cox proportional hazard modeling to identify predictors of disease extension.

RESULTS

We identified 169 new cases of UP with a median age of diagnosis of 40 years (range: 16-91 yr) and a median follow-up of 4.3 years (range: 3.3-15.1 yr). Fifty-three (31%) patients developed extension over the follow-up time. Compared with nonextenders, the need for immunosuppressive or biologic therapy was significantly higher among extenders (34% versus 2.6%, P < 0.001). In multivariable analyses, compared with UP cases with body mass index <25, the adjusted hazard ratios of extension were 1.75 (95% confidence interval [CI], 0.95-3.23) and 2.77 (95% CI, 1.07-7.14) among overweight and obese patients, respectively (Ptrend = 0.03). Similarly, patients with a history of appendectomy or endoscopic finding of moderate to severe disease had a higher risk of extension (adjusted hazard ratio = 2.74, 95% CI, 1.07-7.01 and 1.96, 95% CI, 1.05-3.67, respectively).

CONCLUSIONS

In a retrospective cohort study, we show that appendectomy, body mass index, and endoscopic activity at the time of diagnosis of proctitis are associated with an increased risk of extension. In addition, our data suggest that extenders are more likely to require immunosuppressive or biologic therapy.