Appendix is a priming site in the development of ulcerative colitis

Appendectomy and Risk of Advanced Colorectal Neoplasia in Inflammatory Bowel Disease: A Nationwide Population-based Cohort Study

BACKGROUND

The aim of this study was to examine the association between appendectomy and advanced colorectal neoplasia (aCRN) in patients with inflammatory bowel disease (IBD).

METHODS

Inflammatory bowel disease patients diagnosed in Denmark in the period 1977 to 2017 were identified from the Danish National Patient Registry. Inflammatory bowel disease patients who underwent appendectomy were matched with up to 10 IBD patients without appendectomy and followed until aCRN, death, or emigration. Absolute risks of aCRN were calculated, treating death and bowel resections as competing risks. Stratified Cox regression was used to calculate adjusted hazard ratios (aHRs) of aCRN, comparing IBD patients with appendectomy to IBD patients without appendectomy.

RESULTS

We identified 3789 IBD patients with appendectomy and 37 676 IBD patients without appendectomy. A total of 573 patients (1.4%) developed aCRN, with an absolute risk of aCRN at 20 years of 4.9% (95% confidence interval [CI], 2.9%-7.7%) for ulcerative colitis (UC) patients with appendectomy after UC diagnosis compared with 2.8% (95% CI, 2.3%-3.3%) for UC patients without appendectomy. Appendectomy after UC was associated with an increased rate of aCRN 5 to 10 years (aHR, 2.5; 95% CI, 1.1-5.5) and 10 to 20 years after appendectomy (aHR, 2.3; 95% CI, 1.0-5.5). Appendectomy prior to UC diagnosis was not associated with an increased rate of aCRN, and Crohn's disease was not associated with the rate of aCRN, regardless of timing or histological diagnosis of the appendix specimen.

CONCLUSIONS

Although appendectomy may have a positive effect on the clinical course of UC, our study suggests that this may come at the expense of a higher risk of aCRN.

The appendix and ulcerative colitis - an unsolved connection

The appendix is thought to have a role in the pathogenesis of ulcerative colitis, but the nature and basis of this association remains unclear. In this Perspective, we consider the biology of the appendix with respect to its immunological function and the microbiome, and how this relates to evidence that supports the involvement of the appendix in ulcerative colitis. In experimental models, removal of the inflamed appendix prevents colitis, and in human observational studies, appendectomy is associated with protection against ulcerative colitis. Further, among people who develop ulcerative colitis, appendectomy before diagnosis might influence the course and outcomes of the disease - some evidence suggests that it protects against colectomy but could increase the risk of colorectal cancer. Appendectomy after onset of ulcerative colitis seems to have disparate consequences. Clinical trials to understand whether appendectomy has a role in the treatment of ulcerative colitis are ongoing. Major questions about the role of the appendix in the pathogenesis of ulcerative colitis remain unanswered, and further research is needed to establish whether the connection is clinically relevant.

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.

The Role of Appendicectomy in Ulcerative Colitis: Systematic Review and Meta-Analysis

BACKGROUND

This updated systematic review and meta-analysis investigates the putative role of the appendix in ulcerative colitis as a therapeutic target.

METHODS

Ovid Medline, Embase, PubMed and CENTRAL were searched with MeSH terms ("appendectomy" OR "appendicitis" OR "appendix") AND ("colitis, ulcerative") through October 2020, producing 1469 references. Thirty studies, including 118 733 patients, were included for qualitative synthesis and 11 for quantitative synthesis. Subgroup analysis was performed on timing of appendicectomy. Results are expressed as odds ratio (OR) with 95% confidence intervals (CIs).

RESULTS

Appendicectomy before UC diagnosis reduces the risk of future colectomy (OR, 0.76; 95% CI, 0.65-0.89; I2 = 5%; P = .0009). Corresponding increased risk of colorectal cancer and high-grade dysplasia are identified (OR, 2.27; 95% CI, 1.11-4.66; P = .02). Significance is lost when appendicectomy is performed after disease onset. Appendicectomy does not affect hospital admission rates (OR, 0.87; 95% CI, 0.68-1.12; I2 = 93%; P = .27), steroid use (OR, 1.08; 95% CI, 0.78-1.49; I2 = 36%; P = .64), immunomodulator use (OR, 1.04; 95% CI, 0.76-1.42; I2 = 19%; P = .79), or biological therapy use (OR, 0.76; 95% CI, 0.44-1.30; I2 = 0%; P = .32). Disease extent and risk of proximal progression are unaffected by appendicectomy. The majority (71% to 100%) of patients with refractory UC avoid colectomy following therapeutic appendicectomy at 3-year follow-up.

CONCLUSIONS

Prior appendicectomy reduces risk of future colectomy. A reciprocal increased risk of CRC/HGD may be due to prolonged exposure to subclinical colonic inflammation. The results warrant further research, as consideration may be put toward incorporating a history of appendicectomy into IBD surveillance guidelines. A potential role for therapeutic appendicectomy in refractory left-sided UC is also identified.

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.

Vermiform Appendix and the Potential for Missed Pathologies

Introduction

The appendix is considered an appendage of little value and is often treated disdainfully, be it as part of evolutionary process, on a grossing table, under a microscope or while archiving specimens and slides. It is only recently, with data indicating its importance in gut immunity and as the origin of pseudomyxoma, that its space in a human body appears vindicated.

Aim

Our aim was to screen the histopathologic spectrum of appendix lesions observed in our hospital for rare, incidental or clinico-radiologically uncertain lesions that would help emphasize a necessary seriousness in its sampling.

Method

All appendectomy specimens over ten years were screened for diagnosis other than acute/chronic/resolving appendicitis and pseudomyxoma peritonei. Among the recorded rare diagnoses, one representative case each, based on interesting history or pathology, was selected for discussion.

Observation

Forty-three lesions were found to meet inclusion criteria comprising 12 varied etiologies. Among these, 25 had a normal-appearing appendix and 27 were not suspected on radiology or on clinical/surgical assessment. Histopathology comprised, among others, neoplastic entities such as (Diffuse large B-cell) lymphoma, metastasis, carcinoid as well as interesting non-neoplastic diagnoses such as pinworm infestation (in the elderly) and (post-menopausal) endometriosis.

Conclusion

Sampling and histopathologic assessment of the appendix should be compulsory, careful and representative. Each specimen must be treated as harboring a potential pathology, until microscopically proven otherwise because missed “rare” diagnoses could delay therapy or alter key management decisions as cancer staging.

Prior Appendectomy and the Onset and Course of Crohn's Disease in Chinese Patients

Background and Aim

The relationship between prior appendectomy and Crohn's disease (CD) has previously revealed conflicting findings. The present study investigates the relationship between prior appendectomy and CD development in Chinese patients.

Methods

A retrospective case-control study was performed to compare prior appendectomy rate between CD patients and age- and gender-matched controls at two Chinese hospitals. The clinical course of CD was determined in patients who underwent and did not undergo appendectomies before CD diagnosis.

Results

A total of 617 CD patients and 617 controls were included. The appendectomy rate before CD diagnosis in patients was higher, when compared to controls (6.65% versus 3.73%, P = 0.033). Appendectomy was a risk factor for the onset of CD independent of smoking in the multivariate analysis (OR: 1.878; 95% CI: 1.111–3.174; P = 0.019). Appendectomies were performed closer to the date of CD diagnosis in the trend test (P = 0.039). The rate of appendectomy within one year or 1-5 years before CD diagnosis was higher in patients when compared to that in controls (0.97% versus 0%, P = 0.031; 1.13% versus 0.32%, P = 0.180). However, the rate of appendectomy over five years before CD diagnosis was close to controls (4.54% versus 3.40%, P = 0.392). No significant differences in disease location, behavior, medication, and intestinal resection between appendectomy and nonappendectomy CD patients were found, even in the subgroup analysis by age of appendectomy.

Conclusion

Prior appendectomy is a risk factor for the onset of CD. However, the appendectomy rate only increased for a short duration before CD diagnosis, likely reflecting a diagnostic bias. Prior appendectomy did not influence the features or course of CD.

Influence of Environmental Factors in the Development and Outcomes of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD), which mainly comprises Crohn's disease (CD) and ulcerative colitis (UC), is a term for chronic inflammatory diseases of the gut arising due to a dysregulated immune response to a dysbiotic gut microbiome on a background of genetic predisposition. However, genetics explains a small fraction of risk, and the external environment plays a large and important role in disease pathogenesis and natural history. Cigarette smoking, one of the earliest- and most-studied risk factors, increases the risk of CD onset and is associated with severe disease. In contrast, although smoking cessation increases the risk of UC onset and relapse, current smoking appears to be protective. Appendectomy is inversely associated with the risk of UC. Various dietary factors may influence risk of IBD, including an inverse association with dietary fiber. Exclusion diets have anecdotal reports of efficacy but lack evidence from rigorous clinical trials. Psychosocial factors such as depression, stress, and sleep disturbance play a role in onset as well as in determining natural history. There is an important need for rigorous studies robustly informing the association and mechanism(s) of influence of the external environment on IBD risk and for clinical trials examining the efficacy of alteration of the environment in ameliorating the course of IBD.

Effects of Appendectomy on the Onset and Course of Ulcerative Colitis in Chinese Patients

Background

Previous epidemiological studies have suggested that appendectomy may be a protective factor against the development of ulcerative colitis (UC). However, the results of these studies were inconsistent, with rare studies in Chinese populations.

Aim

This study examined the associations between appendectomy performed before UC diagnosis and the occurrence and clinical course of UC in Chinese patients.

Methods

A case control study was conducted to compare the rate of appendectomy between UC patients and controls matched for age and sex at two Chinese hospitals. Clinical course of UC was compared between UC patients who underwent appendectomies before UC diagnosis and who did not.

Results

402 UC patients and 402 controls were included. The percentage of appendectomy performed before UC diagnosis in UC patients did not differ significantly from controls (2.74% vs 3.98%, P = 0.442). Subgroup analysis on the basis of localization of UC patients did not find significant difference from controls. The extent of disease involvement in UC patients who underwent appendectomy was smaller than patients who did not (P = 0.009). Appendectomy was found to be significantly related to the location of the disease independent of smoking status in multivariate analysis (P < 0.001). Appendectomy did not influence severity of disease and need for immunosuppressive treatment or colectomy.

Conclusion

We did not find a significant negative association between appendectomy and the UC occurrence in Chinese patients. Appendectomy performed before UC diagnosis may reduce the extent of UC involvement.

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.

Appendectomy does not decrease the risk of future colectomy in UC: results from a large cohort and meta-analysis

OBJECTIVES

Early appendectomy is inversely associated with the development of UC. However, the impact of appendectomy on the clinical course of UC is controversial, generally favouring a milder disease course. We aim to describe the effect appendectomy has on the disease course of UC with focus on the timing of appendectomy in relation to UC diagnosis.

DESIGN

Using the National Institute of Diabetes and Digestive and Kidney Diseases Inflammatory Bowel Disease Genetics Consortium database of patients with UC, the risk of colectomy was compared between patients who did and did not undergo appendectomy. In addition, we performed a meta-analysis of studies that examined the association between appendectomy and colectomy.

RESULTS

2980 patients with UC were initially included. 111 (4.4%) patients with UC had an appendectomy; of which 63 were performed prior to UC diagnosis and 48 after diagnosis. In multivariable analysis, appendectomy performed at any time was an independent risk factor for colectomy (OR 1.9, 95% CI 1.1 to 3.1), with appendectomy performed after UC diagnosis most strongly associated with colectomy (OR 2.2, 95% CI 1.1 to 4.5). An updated meta-analysis showed appendectomy performed either prior to or after UC diagnosis had no effect on colectomy rates.

CONCLUSIONS

Appendectomy performed at any time in relation to UC diagnosis was not associated with a decrease in severity of disease. In fact, appendectomy after UC diagnosis may be associated with a higher risk of colectomy. These findings question the proposed use of appendectomy as treatment for UC.

Appendectomy as a Risk Factor for Bacteremic Biliary Tract Infection Caused by Antibiotic-Resistant Pathogens

Background/Aims

Recent evidence has suggested that appendix plays a pivotal role in the development and preservation of intestinal immune system. The aim of this study is to examine whether prior appendectomy is associated with an increased risk for the development of antibiotic-resistant bacteria in bacteremia from biliary tract infection (BTI).

Methods

Charts from 174 consecutive cases of bacteremia derived from BTI were retrospectively reviewed. Using multivariate analysis, independent risk factors for development of antibiotic-resistant bacteria were identified among the clinical parameters, including a history of appendectomy.

Results

In total, 221 bacteria strains were identified from 174 BTI events. Of those, 42 antibiotic-resistant bacteria were identified in 34 patients. Multivariate analysis revealed that prior appendectomy (Odds ratio (OR), 3.02; 95% confidence interval (CI), 1.15–7.87; p = 0.026), antibiotic use within the preceding three months (OR, 3.06; 95% CI, 1.26–7.64; p = 0.013), and bilioenteric anastomosis or sphincterotomy (OR, 3.77; 95% CI, 1.51–9.66; p = 0.0046) were independent risk factors for antibiotic-resistant bacteria.

Conclusions

Prior appendectomy was an independent risk factor for the development of antibiotic-resistant bacteria in bacteremia from BTI.

Modifiable Environmental Factors in Inflammatory Bowel Disease

PURPOSE OF REVIEW

Environmental factors may influence predisposition to develop inflammatory bowel diseases (Crohn's disease, ulcerative colitis) or alter its natural history by modification of both the host immune response and intestinal microbial composition. The purpose of this review is to translate such evidence into clinical practice by a focus on interventional studies that have modified such environmental influences to improve disease outcomes.

RECENT FINDINGS

Several environmental influences have been identified in the recent literature including tobacco use, diet, antibiotics, vitamin D deficiency, stress, appendectomy, and oral contraceptive use. Some risk factors have similar influences on both Crohn's disease and ulcerative colitis while others are disease-specific or have divergent effects. Emerging epidemiologic evidence has confirmed the association of many of these factors with incident disease using prospective data. In addition, laboratory data has supported their mechanistic plausibility and relevance to intestinal inflammation.

The immunology of the vermiform appendix: a review of the literature

This literature review assesses the current knowledge about the immunological aspects of the vermiform appendix in health and disease. An essential part of its immunological function is the interaction with the intestinal bacteria, a trait shown to be preserved during its evolution. The existence of the appendiceal biofilm in particular has proved to have a beneficial effect for the entire gut. In assessing the influence of acute appendicitis and the importance of a normally functioning gut flora, however, multiple immunological aspects point towards the appendix as a priming site for ulcerative colitis. Describing the immunological and microbiotical changes in the appendix during acute and chronic inflammation of the appendix, this review suggests that this association becomes increasingly plausible. Sustained by the distinct composition of cells, molecules and microbiota, as well as by the ever more likely negative correlation between the appendix and ulcerative colitis, the idea of the appendix being a vestigial organ should therefore be discarded.

Intestinal stem cells and intestinal homeostasis in health and in inflammation: A review

BACKGROUND

The human intestine is a complex group of organs, highly specialized in processing food and providing nutrients to the body. It is under constant threat from microbials and toxins and has therefore developed a number of protective mechanisms. One important mechanism is the constant shedding of epithelial cells into the lumen; another is the production and maintenance of a double-layered mucous boundary in which there is continuous sampling of the luminal microbiota and a persistent presence of antimicrobial enzymes. However, the gut needs commensal bacteria to effectively break down food into absorbable nutrients, which necessitates constant communication between the luminal bacteria and the intestinal immune cells in homeostasis. Disruption of homeostasis, for whatever reason, will give rise to (chronic) inflammation.

DISCUSSION

Both medical and surgical management of this disruption is discussed.

Risk of new-onset type II diabetes after appendicectomy

BACKGROUND

Altered immune function after appendicectomy has been associated with autoimmune disease, even though the mechanisms are not clearly elucidated. This study aimed to investigate whether the frequency of new-onset type II diabetes was increased after appendicectomy in a case-control study.

METHODS

This was a retrospective cohort study from the Taiwan Longitudinal Health Insurance Database 2000. The relative risk was compared with that in the general population using population-based data. Each patient was tracked for a 3-year interval to identify those who developed type II diabetes. Cox proportional hazard regression analysis was used to assess the risk of type II diabetes during follow-up.

RESULTS

A total of 31,512 patients were included in the study, of whom 5252 had an appendicectomy (study cohort) and 26,260 were matched for comparison. Some 714 patients (2.3 per cent) developed type II diabetes during the 3-year follow-up, 161 in the study cohort (3.1 per cent) and 553 in the comparison cohort (2.1 per cent). The adjusted hazard ratio (HR) for type II diabetes in the study cohort was 1.45 (95 per cent c.i. 1.22 to 1.74). This increased risk was most pronounced in men (adjusted HR 1.47, 1.16 to 1.88) and in those with a perforated appendix (adjusted HR 2.28, 1.71 to 3.03), and applied only to patients younger than 65 years of age.

CONCLUSION

An increased risk of new-onset type II diabetes within 3 years after appendicectomy was found in patients aged less than 65 years. The risk was highest in men and in those with complicated appendicitis.

The ACCURE-trial: the effect of appendectomy on the clinical course of ulcerative colitis, a randomised international multicenter trial (NTR2883) and the ACCURE-UK trial: a randomised external pilot trial (ISRCTN56523019)

Background

Over the past 20 years evidence has accumulated confirming the immunomodulatory role of the appendix in ulcerative colitis (UC). This led to the idea that appendectomy might alter the clinical course of established UC. The objective of this body of research is to evaluate the short-term and medium-term efficacy of appendectomy to maintain remission in patients with UC, and to establish the acceptability and cost-effectiveness of the intervention compared to standard treatment.

Methods/Design

These paired phase III multicenter prospective randomised studies will include patients over 18 years of age with an established diagnosis of ulcerative colitis and a disease relapse within 12 months prior to randomisation. Patients need to have been medically treated until complete clinical (Mayo score <3) and endoscopic (Mayo score 0 or 1) remission. Patients will then be randomised 1:1 to a control group (maintenance 5-ASA treatment, no appendectomy) or elective laparoscopic appendectomy plus maintenance treatment. The primary outcome measure is the one year cumulative UC relapse rate - defined both clinically and endoscopically as a total Mayo-score ≥5 with endoscopic subscore of 2 or 3. Secondary outcomes that will be assessed include the number of relapses per patient at 12 months, the time to first relapse, health related quality of life and treatment costs, and number of colectomies in each arm.

Discussion

The ACCURE and ACCURE-UK trials will provide evidence on the role and acceptability of appendectomy in the treatment of ulcerative colitis and the effects of appendectomy on the disease course.

Trial registration

NTR2883; ISRCTN56523019

Appendiceal skip inflammation and ulcerative colitis

In recent decades, the appearance of inflammation near the appendix in patients with distal ulcerative colitis (UC) has been highlighted. Many epidemiological studies have confirmed the link between appendectomy and decreased incidence of UC. However, the clinical significance of appendiceal orifice inflammation (AOI) or peri-appendiceal red patch (PARP) as a "skip lesion" in UC has not been well elucidated. In this review, we summarized the literature regarding AOI/PARP and the role of this lesion in relation to UC. Since the appendiceal "skip area" in UC was first described in 1958, several reports using histologic examination of colectomy specimens and colonoscopy have been published. AOI/PARP has been more frequently associated with distal, mild UC than extensive, severe disease. Although it is still controversial, AOI/PARP seems to have little prognostic implication in the disease course of UC, including remission, relapse and proximal disease extension. However, some case reports have raised the possibility of a relationship between AOI/PARP and appendiceal neoplasms such as appendiceal cystadenoma and appendiceal adenocarcinoma. In addition, some investigators have treated UC patients who were resistant to conventional medical therapy with appendectomy and have reported inconsistent therapeutic effect. Further research may lead to the discovery of etiologic and pathogenic roles of appendiceal inflammation in UC.

The murine appendiceal microbiome is altered in spontaneous colitis and its pathological progression

BACKGROUND

Inflammatory bowel disease (comprising ulcerative colitis and Crohn's disease) is a multifactorial disease that is extensively associated with stool microbiome changes (dysbiosis). Appendicitis and appendectomy limits subsequent colitis, clinically, and in animal models. We wanted to examine how the appendiceal and stool microbiome fared in our spontaneous colitic Winnie (Muc2(-/-)) mice model.

METHODS

Two C57BL/6 and 10 Winnie mice at ages 12 and 15 weeks were euthanized for stool and caecal patch samples. DNA was extracted using the QIAamp DNA Stool Mini Kit then the V1-V3 hypervariable region of the 16S rRNA gene was sequenced using the Roche/454 GS FLX + pyrosequencing instrument. A Galaxy metagenomic pipeline was used to define phyla and families at sequence similarity threshold of ≥ 80%.

RESULTS

Bacteriodetes was decreased in 15-week Winnie mice appendices compared to corresponding stool samples (P < 0.01). Proteobacteria was increased in appendices of Winnie mice compared to corresponding stool samples (P < 0.05). The Bacteroidetes family Rikenellaceae could be identified only in 15-week-old Winnie mice appendices. A higher quantity of Acetobacteraceae (Proteobacteria phylum) was present in 15-week Winnie mice when compared to 12-week Winnie mice (P < 0.01). Helicobacteraceae (Proteobacteria phylum), which is prominent in all Winnie mice, is absent in control mice.

CONCLUSIONS

The appendiceal dysbiosis observed in our Winnie mice is commensurate with, and adds to extant literature data. The presence of Helicobacteraceae (Proteobacteria) only in colitic Winnie mice (but not control mice) is consistent with reports of increased Helicobacter in IBD patients. Bacteroides (Bacteroidetes) decreases may be a reflection of reduced anti-inflammatory commensal species such as B. fragilis. Further research is warranted to expand and delineate the relationship between IBD and the appendix microbiome.

Increased risk of pulmonary tuberculosis among patients with appendectomy in Taiwan

The aim of this study was to determine whether there is a relationship between appendectomy and pulmonary tuberculosis in Taiwan. We designed a case-control study by analyzing the database from the Taiwan National Health Insurance Program. In total, we found 11,366 individuals (aged 20 years and older) with newly diagnosed pulmonary tuberculosis as the case group and 45,464 individuals without pulmonary tuberculosis as the control group from 1998 to 2011. The case group and the control group were matched on sex, age, and index year of diagnosing pulmonary tuberculosis. Using the multivariable unconditional logistic regression model, we measured the odds ratio (OR) and 95 % confidence interval (CI) for the risk of pulmonary tuberculosis associated with appendectomy and other comorbidities. After controlling for covariables, the multivariable unconditional logistic regression model disclosed that the OR of pulmonary tuberculosis was 1.4 in appendectomized patients (95 % CI = 1.13, 1.75) when compared to individuals without appendectomy. In further analysis, comorbidity with chronic obstructive pulmonary diseases (OR = 4.63, 95 % CI = 3.21, 6.68), pneumoconiosis (OR = 7.80, 95 % CI = 1.43, 42.5), chronic kidney diseases (OR = 5.65, 95 % CI = 1.79, 17.8), or diabetes mellitus (OR = 2.11, 95 % CI = 1.30, 3.44) increased the risk of pulmonary tuberculosis in appendectomized patients. Individuals with appendectomy are at a 1.4-fold increased risk of pulmonary tuberculosis. Comorbidities, including chronic obstructive pulmonary disease, pneumoconiosis, chronic kidney diseases, and diabetes mellitus, enhance the risk of pulmonary tuberculosis.

New therapeutic avenues in ulcerative colitis: thinking out of the box

Ulcerative colitis (UC) is a chronic idiopathic inflammatory disease of the gastrointestinal tract that affects the mucosal lining of the colon. Recent epidemiological data show that its incidence and prevalence are increasing in many parts of the world, in parallel with altered lifestyles, improved access to health, improved sanitation and industrialisation rates. Current therapeutic strategies for treating UC have only been moderately successful. Despite major recent advances in inflammatory bowel disease therapeutic resources, a considerable proportion of patients are still refractory to conventional treatment. Less than half of all patients achieve long-term remission, many require colectomy, and the disease still has a major impact on patients' lives. Moreover, recent data point to slightly raised mortality. While these outcomes could be partly improved by optimising current therapeutic strategies, they clearly highlight the need to develop new therapies. Currently, a number of promising and innovative therapeutic approaches are being explored, some of which will hopefully survive to reach the clinic. Until such a time arrives, it is important that a better understanding of the clinical particularities of the disease, an improved knowledge of the host-microbiome negative interactions and of the environmental factors beyond disease development is achieved to obtain the final and desired outcome: to provide better treatment and quality of life for patients with this disabling disease.

Surgery and risk for multiple sclerosis: a systematic review and meta-analysis of case-control studies

BACKGROUND

Although the precise etiology of multiple sclerosis is largely unknown, there is some speculation that a prior history of surgery may be associated with the subsequent risk for developing the disease. Therefore, we aimed to examine surgery as a risk factor for the diagnosis of multiple sclerosis.

METHODS

We searched for observational studies that evaluated the risk for developing multiple sclerosis after surgery that occurred in childhood (≤ 20 years of age) or "premorbid" (> 20 years of age). We specifically included surgeries classified as: tonsillectomy, appendectomy, adenoidectomy, or "surgery". We performed a systematic review and meta-analyses and calculated odds ratios (OR) and their 95% confidence intervals (CIs) using a random effects model.

RESULTS

We identified 33 case-control studies, involving 27,373 multiple sclerosis cases and 211,756 controls. There was a statistically significant association between tonsillectomy (OR = 1.32, 95% CI 1.08-1.61; 12 studies, I(2) = 44%) and appendectomy (OR = 1.16, 95% CI 1.01-1.34; 7 studies, I(2) = 0%) in individual's ≤ 20 years of age and the subsequent risk for developing multiple sclerosis. There was no statistically significant association between risk for multiple sclerosis and tonsillectomy occurring after age 20 (OR = 1.20, 95% CI 0.94-1.53; 9 studies, I(2) = 32%), in those with appendectomy at > 20 years (OR = 1.26, 95% CI 0.92-1.72; 5 studies, I(2) = 46%), and in those with adenoidectomy at ≤ 20 years of age (OR = 1.06, 95% CI 0.68-1.68; 3 studies, I(2) = 35%). The combined OR of 15 studies (N = 2,380) looking at "surgery" before multiple sclerosis diagnosis was not statistically significant (OR = 1.19, 95% CI 0.83-1.70; I(2) = 71%).

CONCLUSIONS

We found a small but statistically significant and clinically important increased risk for developing multiple sclerosis, in those with tonsillectomy and appendectomy at ≤ 20 years of age. There was no convincing evidence to support the association of other surgeries and the risk for multiple sclerosis. Well-designed prospective etiological studies, pertaining to the risk for developing multiple sclerosis, ought to be conducted and should include the examination of various surgeries as risk factors.

[Hungarian data on inflammatory bowel diseases: analytical data on ulcerative colistis]

Prospective data collection seems to be essential in evidence-based medicine. Because of the new therapeutic options, the need for standard data collection and testing has significantly increased. In Hungary, a registry for patients with inflammatory bowel disease has already been set up, which makes it possible for clinicians to collect prospective data on their patients.

AIM

Basic characteristics of the database of patients with ulcerative colitis are presented in this paper.

METHODS

The inflammatory bowel disease registry uses the programme of Microsoft Access database management system. Data are stored in a central server.

RESULTS

The incidence of inflammatory bowel diseases has been permanently increasing in Hungary; however, its overall prevalence is still low among the European countries. The frequent administration of immunosuppressive medications (azathioprine and corticosteroids) and their increased doses worsen the estimation of the activity.

CONCLUSIONS

1., It would be very useful to gain prospective data from all national centres. This kind of database would be able to give a complete picture regarding the Hungarian therapeutical practice. 2., Medications of patients may alter the clinical value of the laboratory findings in the process of determining the severity of the disease.

The effect of appendectomy on the course of ulcerative colitis: a systematic review

AIM

Previous studies have shown significantly lower appendectomy rates in ulcerative colitis (UC) patients compared with healthy controls. Evidence indicating that the appendix has an immunomodulatory role in UC has been accumulating. To examine the latest evidence on the effect of appendectomy on the disease course of UC.

METHOD

PubMed, The Cochrane Library and EMBASE were searched. Primary end-points were number of relapses, use of steroids, number of hospital admissions and number of colectomies.

RESULTS

The search resulted in six observational studies (five case-control studies and one cohort study) totalling 2532 patients. Owing to clinical heterogeneity, no meta-analysis could be conducted. One study found lower relapse rates in patients appendectomized before the onset of UC [absolute risk reduction (ARR)=21.5%; 95% CI: 1.71-45.92%]. Another two studies found a reduced requirement for immunosuppression in appendectomized patients (ARR=20.2%; 95% CI: 9.67-30.46% in the first study and ARR=21.4%; 95% CI: 10.32-32.97% in the second study). In addition, one study found lower colectomy rates in nonappendectomized patients (ARR=8.7%; 95% CI: 1.29-18.66%) and two studies found lower colectomy rates in appendectomized patients (ARR=21.4%; 95% CI: 13.17-28.79% in the first study and ARR=18.7%; 95% CI: 7.50-29.97% in the second study).

CONCLUSION

There are limited and conflicting data available regarding the effect of appendectomy on the disease course of UC. Most studies suggest a beneficial effect and the minority find no, or a negative, effect.

[Remission of ulcerative colitis after appendectomy: a case report]

The inverse correlation of appendectomy and ulcerative colitis is well known, but the effect of appendectomy on the clinical course of ulcerative colitis remains unclear. Although the majority of opinions were negative for the therapeutic advantage of appendectomy in patients with ulcerative colitis, advocates for positive effect of appendectomy have been proposed in a few case reports and a prospective study from Western countries. We herein report a case of ulcerative colitis who experienced clinical remission after appendectomy for acute appendicitis. The patient was 35 year old male and had been managed with immunosuppressant before appendectomy. The very acute change in clinical course and a long period of remission after appendectomy highly suggest the therapeutic effect of appendectomy for ulcerative colitis.

Appendiceal Orifice Inflammation in an 8-Year-Old Girl with Ulcerative Colitis Complicating Wilson's Disease

Appendiceal orifice inflammation (AOI) may occur as a skipped lesion in ulcerative colitis (UC). Cases of ulcerative colitis complicated by Wilson's disease have also been reported. We report herein a case of AOI that occurred as a missed lesion in an 8-year-old girl with UC complicating Wilson's disease, which is rare in children.

Appendicectomy as a therapy for ulcerative proctitis

OBJECTIVES

Available data regarding whether appendicectomy performed after the onset of ulcerative colitis can modulate its clinical course are currently limited. This study aimed at addressing this issue.

METHODS

In this study, we report a prospective case series of 30 adult patients (median age 35 years, range 17-70 years; male/female: 11/19) with ulcerative proctitis (median duration of symptoms 5 years, range 8 months to 30 years; median Simple Clinical Colitis Activity Index score 9, range 7-12), who underwent appendicectomy in the absence of any history suggestive of previous appendicitis. Patients were subsequently followed up clinically with the assessment of the Simple Clinical Colitis Activity Index for a median of 14 months (range 9-32 months).

RESULTS

After appendicectomy, the clinical activity index improved significantly to a median score of 2 (range 0-12) (P<0.0005). The improvement in the clinical activity index occurred in 27 of 30 (90%) patients, whereas the index remained unchanged in the remaining 3 of 30 (10%) patients. Furthermore, 12 of 30 (40%) patients experienced a complete resolution of symptoms (clinical activity index score of 0) by 12 months, such that all pharmacological treatments could be withdrawn, and have remained in remission off all previous treatments for a median 9 months (range 6-25 months). The time required for a complete resolution of symptoms post appendicectomy ranged from 1 to 12 months (median 3 months) (Kaplan-Meier analysis). None of the clinical or histological factors analyzed were significantly associated with post-appendicectomy outcome.

CONCLUSIONS

This case series, the largest reported so far, provides rationale for controlled trials to properly evaluate the possible role of appendicectomy in the treatment of ulcerative proctitis.

Small intestinal bacterial overgrowth recurrence after antibiotic therapy

OBJECTIVES

Current treatment for small intestinal bacterial overgrowth (SIBO) is based on courses of broad-spectrum antibiotics. No data concerning SIBO recurrence are available. The aims of the present study were to investigate SIBO recurrence as assessed by glucose breath test (GBT) after antibiotic treatment and conditions associated to SIBO recurrence.

METHODS

Eighty consecutive patients affected by SIBO and decontaminated by rifaximin (1,200 mg per day for 1 wk) were enrolled. Diagnosis of SIBO was based on GBT. GBT was reassessed at 3, 6, and 9 months after evidence of GBT normalization. GBT positivity recurrence, predisposing conditions, and gastrointestinal symptoms were evaluated.

RESULTS

Ten (10/80, 12.6%), 22 (22/80, 27.5%), and 35 (35/80, 43.7%) patients showed positivity to GBT at 3, 6, and 9 months after successful antibiotic treatment, respectively. At multivariate analysis, older age (OR 1.09, 95% CI 1.02-1.16), history of appendectomy (OR 5.9, 95% CI 1.45-24.19), and chronic use of proton pump inhibitors (PPIs) (OR 3.52, 95% CI 1.07-11.64) were significantly associated to GBT positivity recurrence. All gastrointestinal symptoms significantly increased at 3, 6, and 9 months in patients with evidence of GBT positivity recurrence.

CONCLUSIONS

GBT positivity recurrence rate was high after antibiotic treatment. Older age, history of appendectomy, and chronic use of PPIs were associated with GBT positivity recurrence. Patients with evidence of GBT positivity recurrence showed gastrointestinal symptoms relapse thus suggesting SIBO recurrence.