Management consensus of inflammatory bowel disease for the Asia-Pacific region

Differentiation of Crohn's disease, ulcerative colitis, and intestinal tuberculosis by dual-layer spectral detector CT enterography

AIM

To investigate the value of radiological features and energy spectrum quantitative parameters in the differential diagnosis of Crohn's disease (CD), ulcerative colitis (UC), and intestinal tuberculosis (ITB) by dual-layer spectral detector computed tomography (CT) enterography (CTE).

MATERIALS AND METHODS

Clinical and CTE data were collected from 182 patients with CD, 29 with UC, and 51 with ITB. CT images were obtained at the enteric phases and portal phases. The quantitative energy spectrum parameters were iodine density (ID), normalised ID (NID), virtual non-contrast (VNC) value, and effective atomic number (Z-eff). The area under curve (AUC) of the receiver operating characteristic curve (ROC) was calculated.

RESULTS

The vascular comb sign (p=0.009) and enlarged lymph nodes (p=0.001) were more common in patients with CD than UC or ITB. In the differentiation of moderate-severe active CD from UC, enteric phase NID (AUC, 0.938; p<0.001) and portal phase Z-eff (AUC, 0.925; p<0.001) had the highest accuracy, which were compared separately. In the differentiation of moderate-severe active CD from ITB, enteric phase NID (AUC, 0.906; p<0.001) and portal phase Z-eff (AUC, 0.947; p<0.001) had the highest accuracy; however, the AUC value was highest when the four parameters are combined (AUC, 0.989; p<0.001; AUC, 0.986; p<0.001; AUC, 0.936; p<0.001; and AUC, 0.986; p<0.001).

CONCLUSION

The present study shows that the combined strategies of four parameters have higher sensitivity and specificity in differentiating CD, UC, and ITB, and may play a key role in guiding treatment.

Few-shot learning for the classification of intestinal tuberculosis and Crohn's disease on endoscopic images: A novel learn-to-learn framework

Background and aim

Standard deep learning methods have been found inadequate in distinguishing between intestinal tuberculosis (ITB) and Crohn's disease (CD), a shortcoming largely attributed to the scarcity of available samples. In light of this limitation, our objective is to develop an innovative few-shot learning (FSL) system, specifically tailored for the efficient categorization and differential diagnosis of CD and ITB, using endoscopic image data with minimal sample requirements.

Methods

A total of 122 white-light endoscopic images (99 CD images and 23 ITB images) were collected (one ileum image from each patient). A 2-way, 3-shot FSL model that integrated dual transfer learning and metric learning strategies was devised. Xception architecture was selected as the foundation and then underwent a dual transfer process utilizing oesophagitis images sourced from HyperKvasir. Subsequently, the eigenvectors derived from the Xception for each query image were converted into predictive scores, which were calculated using the Euclidean distances to six reference images from the support sets.

Results

The FSL model, which leverages dual transfer learning, exhibited enhanced performance metrics (AUC 0.81) compared to a model relying on single transfer learning (AUC 0.56) across three evaluation rounds. Additionally, its performance surpassed that of a less experienced endoscopist (AUC 0.56) and even a more seasoned specialist (AUC 0.61).

Conclusions

The FSL model we have developed demonstrates efficacy in distinguishing between CD and ITB using a limited dataset of endoscopic imagery. FSL holds value for enhancing the diagnostic capabilities of rare conditions.

Quantitative analysis of the three gut microbiota in UC and non-UC patients using real-time PCR

BACKGROUND

and study aims: Gastrointestinal microbiota are closely related to the pathogenesis of ulcerative colitis (UC). This study aimed at quantification of F. prausnitzii, Provetella, and Peptostreptococcus in UC and non-UC patients using Real-Time PCR and a new set of primers were also validated for this purpose.

MATERIALS AND METHODS

In this study, the relative abundance of microbial populations between the UC and non-UC subjects were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR). DNA extraction from biopsies and polymerase chain reaction (PCR) amplification of bacterial 16S rRNA gene-targeted species-specific primers was performed to detect the anaerobic bacterial species. The qRT-PCR was used to show the relative change in the bacterial populations of F. prausnitzii, Provetella, and Peptostreptococcus in the UC and non-UC subjects.

RESULTS

Our data for detection of the anaerobic intestinal flora showed Faecalibacterium prausnitzii, Provetella and Peptostreptococcus were the predominant microflora in the controls and showed significant differences (p = 0.002, 0.025 and 0.039, respectively). The qRT-PCR analyses of F. prausnitzii, Provetella and Peptostreptococcus were 8.69-, 9.38- and 5.77-higher, respectively, in the control group than in the UC group.

CONCLUSION

The results of this study showed decreased abundance of F. prausnitzii, Provetella and Peptostreptococcus in the intestine of UC patients in comparison to non-UC patients. Quantitative RT-PCR, as a progressive and sensitive method, could be useful for evaluation of bacterial populations in patients with inflammatory bowel diseases to attain appropriate therapeutic strategies.

Computed tomography enterography-based multiregional radiomics model for differential diagnosis of Crohn's disease from intestinal tuberculosis

PURPOSE

To build computed tomography enterography (CTE)-based multiregional radiomics model for distinguishing Crohn's disease (CD) from intestinal tuberculosis (ITB).

MATERIALS AND METHODS

A total of 105 patients with CD and ITB who underwent CTE were retrospectively enrolled. Volume of interest segmentation were performed on CTE and radiomic features were obtained separately from the intestinal wall of lesion, the largest lymph node (LN), and region surrounding the lesion in the ileocecal region. The most valuable radiomic features was selected by the selection operator and least absolute shrinkage. We established nomogram combining clinical factors, endoscopy results, CTE features, and radiomic score through multivariate logistic regression analysis. Receiver operating characteristic (ROC) curves and decision curve analysis (DCA) were used to evaluate the prediction performance. DeLong test was applied to compare the performance of the models.

RESULTS

The clinical-radiomic combined model comprised of four variables including one radiomic signature from intestinal wall, one radiomic signature from LN, involved bowel segments on CTE, and longitudinal ulcer on endoscopy. The combined model showed good diagnostic performance with an area under the ROC curve (AUC) of 0.975 (95% CI 0.953-0.998) in the training cohort and 0.958 (95% CI 0.925-0.991) in the validation cohort. The combined model showed higher AUC than that of the clinical model in cross-validation set (0.958 vs. 0.878, P = 0.004). The DCA showed the highest benefit for the combined model.

CONCLUSION

Clinical-radiomic combined model constructed by combining CTE-based radiomics from the intestinal wall of lesion and LN, endoscopy results, and CTE features can accurately distinguish CD from ITB.

Drug therapy and monitoring for inflammatory bowel disease: a multinational questionnaire investigation in Asia

Background/Aims

The incidence and prevalence of inflammatory bowel disease (IBD) is rising in Asia recently. The study aimed to obtain a comprehensive understanding of the current status of drug therapy and monitoring for IBD in Asia.

Methods

A questionnaire investigation on drug therapy and monitoring for IBD was conducted right before the 6th Annual Meeting of Asian Organization for Crohn’s & Colitis. Questionnaires were provided to Asian physicians to fill out via emails between March and May 2018.

Results

In total, responses of 166 physicians from 129 medical centers were included for analysis. Among the surveyed regions, the most average number of IBD specialist gastroenterologists and nurses was 4.8 per center in Taiwan and 2.5 per center in Mainland China, respectively. 5-Aminosalicylic acid/sulfasalazine (99.4%) was the most preferred first-line choice for mild-moderate ulcerative colitis (UC), meanwhile corticosteroid (83.7%) was widely applied for severe UC. The first-line medication for Crohn’s disease (CD) markedly varied as corticosteroid (68.1%) was the most favored in Mainland China, Japan, and South Korea, followed by infliximab (52.4%) and azathioprine (47.0%). Step-up strategy was preferred in mild-moderate UC (96.4%), while 51.8% of the physicians selected top-down treatment for CD. Only 25.9% and 17.5% of the physicians could test blood concentration of infliximab and antibody to infliximab in their hospitals, respectively.

Conclusions

The current status of drug therapy and monitoring for IBD in Asia possesses commonalities as well as differences. Asian recommendations, IBD specialist teams and practice of therapeutic drug monitoring are required to improve IBD management in Asia.

Development and validation of a new algorithm model for differential diagnosis between Crohn's disease and intestinal tuberculosis: a combination of laboratory, imaging and endoscopic characteristics

Background

Sometimes in clinical practice, it is a great challenge to distinguish Crohn's disease (CD) and intestinal tuberculosis (ITB), we conducted this study to identify simple and useful algorithm for distinguishing them.

Methods

We retrospectively reviewed the medical history of the patients who were diagnosed as ITB or CD. We firstly identified ITB patients, and then the patients diagnosed with CD were matched by age, sex, and admission time in a 1:1 ratio. Patients who admitted between May 1, 2013 and April 30, 2019 were regarded as training cohort, and patients admitted between May 1, 2019 and May 1, 2020 were regarded as validation cohort. We used multivariate analysis to identify the potential variables, and then we used R package rpart to build the classification and regression tree (CART), and validated the newly developed model.

Results

In total, the training cohort included 84 ITB and 84 CD patients, the validation cohort included 22 ITB and 22 CD patients. Multivariate analysis showed that, positive interferon-gamma release assays (IGRAs), ≥ 4 segments involved, longitudinal ulcer, circular ulcer, and aphthous ulcer were confirmed as independent discriminating factors. Using these parameters to build the CART model made an overall accuracy rate was 88.64%, with sensitivity, specificity, NPV, and PPV being 90.91%, 86.36%, 90.48% and 86.96%, respectively.

Conclusion

We developed a simple and novel algorithm model covering laboratory, imaging, and endoscopy parameters with CART to differentiate ITB and CD with good accuracy. Positive IGRAs and circular ulcer were suggestive of ITB, while ≥ 4 segments involved, longitudinal ulcer, and aphthous ulcer were suggestive of CD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-021-01838-x.

LightCUD: a program for diagnosing IBD based on human gut microbiome data

Background

The diagnosis of inflammatory bowel disease (IBD) and discrimination between the types of IBD are clinically important. IBD is associated with marked changes in the intestinal microbiota. Advances in next-generation sequencing (NGS) technology and the improved hospital bioinformatics analysis ability motivated us to develop a diagnostic method based on the gut microbiome.

Results

Using a set of whole-genome sequencing (WGS) data from 349 human gut microbiota samples with two types of IBD and healthy controls, we assembled and aligned WGS short reads to obtain feature profiles of strains and genera. The genus and strain profiles were used for the 16S-based and WGS-based diagnostic modules construction respectively. We designed a novel feature selection procedure to select those case-specific features. With these features, we built discrimination models using different machine learning algorithms. The machine learning algorithm LightGBM outperformed other algorithms in this study and thus was chosen as the core algorithm. Specially, we identified two small sets of biomarkers (strains) separately for the WGS-based health vs IBD module and ulcerative colitis vs Crohn’s disease module, which contributed to the optimization of model performance during pre-training.

We released LightCUD as an IBD diagnostic program built with LightGBM. The high performance has been validated through five-fold cross-validation and using an independent test data set. LightCUD was implemented in Python and packaged free for installation with customized databases. With WGS data or 16S rRNA sequencing data of gut microbiome samples as the input, LightCUD can discriminate IBD from healthy controls with high accuracy and further identify the specific type of IBD. The executable program LightCUD was released in open source with instructions at the webpage http://cqb.pku.edu.cn/ZhuLab/LightCUD/. The identified strain biomarkers could be used to study the critical factors for disease development and recommend treatments regarding changes in the gut microbial community.

Conclusions

As the first released human gut microbiome-based IBD diagnostic tool, LightCUD demonstrates a high-performance for both WGS and 16S sequencing data. The strains that either identify healthy controls from IBD patients or distinguish the specific type of IBD are expected to be clinically important to serve as biomarkers.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13040-021-00241-2.

Systematic review and meta-analysis of the incidence and prevalence and 30-year trend of inflammatory bowel diseases in Asia: a study protocol

INTRODUCTION

Inflammatory bowel diseases, including ulcerative colitis (UC), Crohn's disease (CD) and inflammatory bowel disease type unclassified (IBDU), are debilitating conditions that are rapidly growing in developing countries. Given the absence of a comprehensive systematic review and meta-analysis containing a rigorous pooled estimate of incidence and prevalence of UC, CD and IBDU, this study was conducted to determine the incidence and prevalence of these conditions in Asia and their 30-year trend.

METHODS AND ANALYSIS

Based on predefined criteria, electronic databases, including PubMed/MEDLINE, Scopus, WoS (Clarivate Analytics), Embase and Google Scholar, and some databases pertaining to Asian countries will be searched for population-based cross-sectional studies and the baseline data and final reports of population-based cohort studies involving paediatric and adult patients, with no language restrictions, from 1 January 1988 to 30 December 2018. Any disagreement in the stages of screening, selecting, quality assessment and data extraction between the two independent reviewers will be resolved by consensus, and if the disagreement is not resolved, a third expert opinion will be sought. The combination method will be used based on methodological similarities in the included studies by the Fixed Effect Model or the Random Effect Model. Forest plots will be plotted for all the studies to show the separated and pooled incidence and prevalence and their corresponding 95% CIs. The Q-statistic test and I² statistic will be used to assess statistical heterogeneity. Funnel plots will be used to assess potential reporting bias and nonsignificant study effect. Begg's and Egger's tests will also be performed, and significant results (p>0.1) shall suggest a publication bias, in which case the 'trim and fill' method will be used. The time trends for UC, CD and IBDU will be calculated using a cumulative meta-analysis.

ETHICS AND DISSEMINATION

Since this review will use previously published studies, it will not require the consent of an Ethics Committee. The results will be prepared and disseminated through a peer-reviewed journal and will be presented in relevant conferences.

PROSPERO REGISTRATION NUMBER

CRD42019131477.

Alteration of Gut Microbiota in Inflammatory Bowel Disease (IBD): Cause or Consequence? IBD Treatment Targeting the Gut Microbiome

Inflammatory bowel disease (IBD) is a chronic complex inflammatory gut pathological condition, examples of which include Crohn’s disease (CD) and ulcerative colitis (UC), which is associated with significant morbidity. Although the etiology of IBD is unknown, gut microbiota alteration (dysbiosis) is considered a novel factor involved in the pathogenesis of IBD. The gut microbiota acts as a metabolic organ and contributes to human health by performing various physiological functions; deviation in the gut flora composition is involved in various disease pathologies, including IBD. This review aims to summarize the current knowledge of gut microbiota alteration in IBD and how this contributes to intestinal inflammation, as well as explore the potential role of gut microbiota-based treatment approaches for the prevention and treatment of IBD. The current literature has clearly demonstrated a perturbation of the gut microbiota in IBD patients and mice colitis models, but a clear causal link of cause and effect has not yet been presented. In addition, gut microbiota-based therapeutic approaches have also shown good evidence of their effects in the amelioration of colitis in animal models (mice) and IBD patients, which indicates that gut flora might be a new promising therapeutic target for the treatment of IBD. However, insufficient data and confusing results from previous studies have led to a failure to define a core microbiome associated with IBD and the hidden mechanism of pathogenesis, which suggests that well-designed randomized control trials and mouse models are required for further research. In addition, a better understanding of this ecosystem will also determine the role of prebiotics and probiotics as therapeutic agents in the management of IBD.

CT Enterography score: a potential predictor for severity assessment of active ulcerative colitis

BACKGROUND

Evaluate the possibility of CT enterography (CTE) score system as a predictor in assessing active ulcerative colitis (UC) severity.

METHODS

Forty-six patients with active UC with CTE and colonoscopy were enrolled. Based on modified Mayo score, patients were divided into three groups: mild (n = 10), moderate (n = 17) and severe (n = 19). A cumulative CTE score was calculated in each patient and its correlation with modified Mayo score was analyzed. The optimal cutoff values of CTE score were determined by receiver operating characteristic (ROC) curves analysis.

RESULTS

Significant between-group differences were observed in CTE spectrums of mucosal bubbles, mural stratification, loss of haustration, enlarged mesenteric lymph nodes and engorged mesenteric vessels (P < 0.05). The cumulative CTE scores were significant difference between three groups (CTE score:4.9 ± 2.3, 7.6 ± 2.6, and 10.9 ± 2.0, respectively, P < 0.01). The cumulative CTE score showed a positive correlation with modified Mayo score (r = 0.835, P < 0.05). The optimal cut-off value for CTE score predicting moderate and severe UC was 9.5 (area under the curve [AUC]:0.847, sensitivity:78.9%, specificity:82.4%).

CONCLUSION

Disease severity assessment by CTE score demonstrates strong positive correlation with severity established modified Mayo score. CTE score system maybe a potential predictor for active UC severity assessment.

Diagnostic Performance of a 5-Marker Predictive Model for Differential Diagnosis Between Intestinal Tuberculosis and Crohn's Disease

BACKGROUND

The differentiation between intestinal tuberculosis (ITB) and Crohn's disease (CD) is a challenge. The aim of this study was to investigate a predictive model for differential diagnosis between ITB and CD.

METHODS

A total of 268 patients who were suspected of having ITB or CD were prospectively recruited between January 2013 and September 2016. The clinical, laboratory, radiological, endoscopic, and histological features were investigated and subjected to univariate and multivariate analyses. The final predictive model was developed based on the regression coefficients of multivariate logistic regression. To validate the model, the same regression equation was tested on the other group.

RESULTS

A total of 239 patients had a final diagnosis, including 86 ITB and 153 CD. Five variables (perianal disease, pulmonary involvement, longitudinal ulcer, left colon, and ratio of tuberculosis-specific antigen to phytohaemagglutinin) were selected for the predictive model to discriminate between ITB and CD. In the predictive model of the training data set, the area under the receiver operating characteristic (ROC) curve, sensitivity, specificity, and accuracy, with a cutoff level of 0.29, were 0.975 (95% confidence interval [CI], 0.939-0.993), 96.7%, 90.7%, and 92.8%, respectively. Application of the predictive model to the validation data set showed similar performance in distinguishing ITB from CD. The area under the ROC curve, sensitivity, specificity, and accuracy were 0.950 (95% CI, 0.871-0.987), 88.5%, 93.5%, and 91.7%, respectively.

CONCLUSIONS

This 5-marker predictive model could be conveniently used by clinicians to draw a reliable differential diagnosis between ITB and CD in clinical practice. 10.1093/ibd/izy154_video1izy154.video15790725497001.

A Systematic Review of Epidemiology and Risk Factors Associated With Chinese Inflammatory Bowel Disease

Background: Recent epidemiological data have revealed a dramatically rising prevalence and incidence of inflammatory bowel diseases (IBDs) in Mainland China, a rapidly growing industrialized region, over the last two decades. Objectives: We performed a systematic review to investigate the changing trends in the incidence of IBD in Mainland China and summarized the recent findings in risk factors associated with Chinese IBD. Methods: Relevant references were obtained from an electronic database search via MEDLINE and EMBASE (for English literatures), the China Academic Journals Full-text Database (CJFD) and the China Science Periodical Database (CSPD) in Wanfang Data (for Chinese literatures). Results: Total 1,584 abstracts in Chinese and 171 abstracts in English were collected. Eight full-text with epidemiological data, 25 with risk factor data in Chinese and 7 full-text with epidemiological data, 12 with risk factor data in English were finally identified and included for analysis. Data from included epidemiological studies has showed a striking increase in the incidence rate of IBD in Mainland China over time, and current incidence rates for IBD, UC, and CD were 1.80 (IBD), 1.33 (UC), and 0.46/1,000,000 (CD), though it varies among regions and ethnic minority populations. In addition, several risk factors including environmental factors, diet, intestinal infectious agents, hygiene, stress, and lifestyle have been reported to be associated with the increased incidence of Chinese IBD. Conclusion: This systematic review revealed an increased incidence of IBD in Mainland China. Although it is still lower than that in the Western world, however, China has a huge population; therefore, the total number of IBD patients might not be so little as previously thought and the disease burden of IBD in China is likely underestimated. HIGHLIGHTS Recent epidemiological data have revealed a dramatically rising prevalence and incidence of inflammatory bowel diseases (IBD) in Mainland China, a rapidly growing industrialized region, over the last two decades.This systematic review based on recent epidemiological data has revealed a striking increase in the incidence rate of IBD in Mainland China, though it varies among regions and ethnic minority populations.Several potential risk factors of IBD including environmental factors, diet, intestinal infectious agents, hygiene, stress, and lifestyle have been reported to be associated with the increased incidence of Chinese IBD.This systematic review on epidemiologic and risk factor studies has expanded understanding of the occurrence, distribution, geographic variance and risk factors of Chinese IBD and will provide clinicians important information in understanding current status of IBD in Mainland China.

Fecal microbial dysbiosis in Chinese patients with inflammatory bowel disease

AIM

To analyze the alterations of fecal microbiota in Chinese patients with inflammatory bowel disease (IBD).

METHODS

Fecal samples from 15 patients with Crohn’s disease (CD) (11 active CD, 4 inactive CD), 14 patients with active ulcerative colitis (UC) and 13 healthy individuals were collected and subjected to 16S ribosomal DNA (rDNA) gene sequencing. The V4 hypervariable regions of 16S rDNA gene were amplified from all samples and sequenced by the Illumina MiSeq platform. Quality control and operational taxonomic units classification of reads were calculated with QIIME software. Alpha diversity and beta diversity were displayed with R software.

RESULTS

Community richness (chao) and microbial structure in both CD and UC were significantly different from those in normal controls. At the phyla level, analysis of the microbial compositions revealed a significantly greater abundance of Proteobacteria in IBD as compared to that in controls. At the genera level, 8 genera in CD and 23 genera in UC (in particular, the Escherichia genus) showed significantly greater abundance as compared to that in normal controls. The relative abundance of Bacteroidetes in the active CD group was markedly lower than that in the inactive CD group. The abundance of Proteobacteria in patients with active CD was nominally higher than that in patients with inactive CD; however, the difference was not statistically significant after correction. Furthermore, the relative abundance of Bacteroidetes showed a negative correlation with the CD activity index scores.

CONCLUSION

Our study profiles specific characteristics and microbial dysbiosis in the gut of Chinese patients with IBD. Bacteroidetes may have a negative impact on inflammatory development.

Evaluating the Association of Common Variants of the SLC44A4 Gene with Ulcerative Colitis Susceptibility in the Han Chinese Population

OBJECTIVE

The SLC44A4 gene was recently reported to be associated with ulcerative colitis (UC) susceptibility in the Indian and Japanese populations. The aim of our study was to investigate the association of common variants within the SLC44A4 gene and the susceptibility to UC among the Han Chinese.

METHODS

We examined 16 tag single nucleotide polymorphisms (SNPs) within the SLC44A4 gene in a Han Chinese population that consisted of 311 UC patients and 675 healthy controls; both SNP and haplotypic association analyses were performed.

RESULTS

We found that rs2736428 was significantly associated with UC risk (allelic p = 0.0004), and the CT and TT genotypes of rs2736428 had a higher distribution compared with the CC genotypes (genotypic p = 0.001), suggesting that the T allele was a risk allele (odds ratio = 1.45, 95% confidence interval = 1.18-1.78). Moreover, one haplotype block that included rs2736428 was found to be strongly associated with UC risk as well (global p < 0.001).

CONCLUSION

Our results provide further supportive evidence for an important role of the SLC44A4 gene in the pathogenesis of UC.

Emerging Gastrointestinal and Liver Diseases in Asia Pacific: Implications to Health Care in the Region (World Gastroenterology Organization: Asian Pacific Association of Gastroenterology Distinguished Global Lecture 2015)

Colorectal cancer (CRC), gastroesophageal reflux disease (GERD), inflammatory bowel disease (IBD), and nonalcoholic fatty liver disease are considered important emerging diseases in the Asia Pacific (AP) region. The incidence rate of CRC is the highest among gastrointestinal cancers in the region surpassing that of gastric cancer. However, population CRC screening is limited by availability of adequate health resources and financing. GERD is a highly prevalent disease in AP with the prevalence of GERD symptoms and reflux esophagitis reported to be increasing. The usage of proton pump inhibitors has also been reported to be high. The incidence and prevalence of IBD is not as high as in the west but is now an increasingly recognizable disease in the AP region. Being a complicated disease, IBD will pose a huge financial burden with the increasing use of expensive biological drugs. In tandem with the exponential increase in obesity and diabetes mellitus in AP, nonalcoholic fatty liver disease will become the most important liver disease in the region in the coming years. These emerging diseases reflect the continued fast-paced socioeconomic development in the region with marked lifestyle changes and increasing affluence.

Predictive Factors for Differentiating Between Crohn's Disease and Intestinal Tuberculosis in Koreans

OBJECTIVES

A differential diagnosis between intestinal tuberculosis (ITB) and Crohn's disease (CD) is challenging. The aim of this study was to investigate the clinical, endoscopic, and histological features and to create a predictive score model for differentiating CD and ITB.

METHODS

In total, 261 patients, 99 with ITB and 162 with CD, were recruited from seven tertiary centers from 2005 to 2013 and reviewed retrospectively. For the creation of a validated model, parameters were selected by univariate logistic regression and receiver operating characteristic curve analyses. Then, the prediction model was established on the basis of β-coefficients of the multivariate logistic regression. For the validation of the model, the same regression equation was tested on the other group.

RESULTS

Age, diarrhea, ring-shaped ulcer, longitudinal ulcer, sigmoid involvement, suspicious radiological pulmonary tuberculosis, and gender were selected as the factors for a seven-marker model. In the seven-marker model of the validation data set, the sensitivity, specificity, positive predictive value, and negative predictive value with a cutoff level of 0.35 were 98.0, 92.4, 88.9, and 98.6, respectively.

CONCLUSIONS

The seven-marker model seems to be highly reliable for differentiating between ITB and CD and could be conveniently used by clinicians to obtain results.

The Same Intestinal Inflammatory Disease despite Different Genetic Risk Factors in the East and West?

Background

Inflammatory bowel disease (IBD) is a chronic inflammatory disease with unknown etiology. It is likely caused by a complex interplay between genetic, immunologic and environmental factors. Although IBD is still relatively uncommon in Asia, a multitude of studies have shown that it is an emerging disease around the world. Recent insights have highlighted both the similarities and differences amongst Asian and Western IBD patients.

Summary

The annual incidence of IBD in the East is still low compared with the West, but there are differences between different regions of Asia. Time trend studies have shown that the incidence of IBD is on the rise. Some notable differences in the clinical manifestations of IBD between the East and West have also been noted. 'Westernization' of lifestyle may encompass various social and environmental changes that account for the emergence of IBD in our population, although genetics also plays a role in disease pathogenesis. Diagnosis and treatment challenges include limited access to medical care in certain areas, limited availability and high cost of medications, lack of insurance reimbursement, paucity of multidisciplinary teams for the management of complicated IBD cases, and a high prevalence of endemic infections. Currently, the risk of colorectal cancer is lower in the East than in the West, but cancer rates will likely approach that of the West in the future as the prevalence of IBD continues to rise.

Key Messages

Measures to improve access to diagnostic tools, increase the availability of medication, and provide adequate multidisciplinary care for IBD patients will become increasingly important in Asia. Differences between the East and West will provide a unique opportunity for global collaboration in basic and clinical research to further our understanding of the disease entity and also provide more locoregional data to healthcare providers and policymakers to make informed decisions and policy changes when tackling the rising burden of IBD in Asia.

Alterations of mucosal microbiota in the colon of patients with inflammatory bowel disease revealed by real time polymerase chain reaction amplification of 16S ribosomal ribonucleic acid

Background & objectives:

Alterations in microbial communities closely associated with the intestinal mucosa are likely to be important in the pathogenesis of inflammatory bowel disease (IBD). We examined the abundance of specific microbial populations in colonic mucosa of patients with ulcerative colitis (UC), Crohn's disease (CD) and controls using reverse transcription quantitative polymerase chain reaction (RT-qPCR) amplification of 16S ribosomal ribonucleic acid (16S rRNA).

Methods:

RNA was extracted from colonic mucosal biopsies of patients with UC (32), CD (28) and patients undergoing screening colonoscopy (controls), and subjected to RT-qPCR using primers targeted at 16S rRNA sequences specific to selected microbial populations.

Results:

Bacteroides-Prevotella-Porphyromonas group and Enterobacteriaceae were the most abundant mucosal microbiota. Bacteroides and Lactobacillus abundance was greater in UC patients compared with controls or CD. Escherichia coli abundance was increased in UC compared with controls. Clostridium coccoides group and C. leptum group abundances were reduced in CD compared with controls. Microbial population did not differ between diseased and adjacent normal mucosa, or between untreated patients and those already on medical treatment. The Firmicutes to Bacteroidetes ratio was significantly decreased in both UC and CD compared with controls, indicative of a dysbiosis in both conditions.

Interpretation & conclusions:

Dysbiosis appears to be a primary feature in both CD and UC. Microbiome-directed interventions are likely to be appropriate in therapy of IBD.

Temporal Change in Phenotypic Behaviour in Patients with Crohn's Disease: Do Indian Patients Behave Differently from Western and Other Asian Patients?

BACKGROUND AND AIMS

In Western studies, one-third of patients with Crohn's disease have stricturing or penetrating disease at presentation and one-half will progress to complicated disease in 20 years. Asian studies indicate that the Asian disease phenotype may be different. Our aim was to study the disease behaviour in Indian patients with Crohn's disease.

METHODS

In this hospital-based study, we analysed [Montreal classification] disease phenotype, presence of perianal disease, need for intestinal surgery, and changes in the Montreal classification over time in Crohn's disease patients from our database.

RESULTS

In the 178 patients (median age 35, interquartile range [IQR] 21 years; 97 males) with Crohn's disease, the proportion of various features was as follows. More patients had ileo-colonic[L3: 43.8%] than ileal[L1: 27.5%] or colonic[L2: 28.7%] disease. Perianal disease was seen in 11.8% at baseline. Non-stricturing, non-fistulising disease[B1] was seen in 74.7%, 65.7%, 50%, and 44.4% at baseline, at 5, 10 and 15 years, respectively. Stricturing disease[B2] was seen in 21.4%, 21.9%, 28.9%, and 33.3%; penetrating disease[B3] in 3.9%, 11.4%, 21%, and 16.7%; and intestinal surgery was required in 10.7%, 20%, 34.2%, and 55.5%, respectively. KaplanMeier analysis showed no association between progression of disease and patient age or the location of the disease.

CONCLUSIONS

Gender distribution and predominant ileo-colonic location of disease were similar to earlier Asian reports on Crohn's disease. Perianal disease was less frequent than reported in Western and other Asian studies. One-fourth of Indian patients had aggressive disease at diagnosis, but the tendency to progress towards aggressive disease over time was less pronounced than in Western patients.

Granulomas as the Most Useful Histopathological Feature in Distinguishing between Crohn's Disease and Intestinal Tuberculosis in Endoscopic Biopsy Specimens

The incidence of Crohn's disease (CD) is increasing in Chinese populations in whom intestinal tuberculosis (ITB) is prevalent.This study aimed to identify differential diagnostic microscopic and endoscopic characteristics of CD from those of ITB.Patients with CD (N = 52) and patients with ITB (N = 16) diagnosed between 2010 and 2013 were identified. Specimens obtained via endoscopy were analyzed microscopically by a pathologist. The relationship between endoscopic appearance and histopathological features was analyzed. The χ test, Fisher's exact probability test, and the Mann-Whitney U test were used.Granulomas were present in 81.3% of ITB cases and in 67.3% of CD cases (P = 0.36). Granulomas in ITB cases were denser than those in CD cases (mean 5.29 ± 4.30 vs. 2.46 ± 3.50 granulomas per 10 low power fields; each low power field = 3.80 mm; P = 0.005). Granulomas in ITB cases were larger (mean widest diameter, 508 ± 314 μm; range, 100-1100 μm) than those in CD cases (mean widest diameter, 253 ± 197 μm; range, 50-800 μm). Basal plasmacytosis was more common in CD cases than in ITB cases (77.0% vs. 37.5%, P = 0.000). Endoscopy findings such as longitudinal ulcer, aphthous ulcer, and cobblestone appearance were only seen in CD cases (34.6%, 21.2%, and 23.1%, respectively). Granulomas were detected in the majority of cases with longitudinal ulcers (88.9%). Basal plasmacytosis was exclusively detected in cases with longitudinal ulcer and a cobblestone appearance.Characteristics of granulomas maybe the most important distinguishing features between CD and ITB. However, the histopathological characteristics of both diseases may overlap on endoscopic biopsy specimens. An accurate diagnosis should be made that considers clinical, endoscopic features, and pathologic findings.

Health-related quality of life in Chinese patients with mild and moderately active ulcerative colitis

Background

Ulcerative colitis (UC) impairs the health-related quality of life (HRQOL). The difference in HRQOL between patients with mild and moderately active UC is not well-defined. Few studies have been conducted to explore the factors that influence HRQOL in Chinese patients. Our study aims were to (1) compare HRQOL of mildly active UC patients with moderate patients; (2) explore the factors that influence HRQOL in Chinese patients with UC; and (3) analyze demographic and disease characteristics of UC in China.

Methods

A total of 110 mild and 114 moderate patients with UC were enrolled. The demographic and disease characteristics were recorded. HRQOL was measured by the Chinese version of the inflammatory bowel disease questionnaire (IBDQ) between mild and moderate patients, male and female patients, and different disease distributions. Stepwise regression analysis was used to assess factors influencing the IBDQ score.

Results

Patients with moderate UC had significantly lower IBDQ total scores compared to patients with mild UC (P=0.001). The IBDQ total score had a negative correlation with the Mayo score (r=–0.263, P<0.001). Stepwise regression analysis showed that the disease activity index and gender had an influence on the IBDQ total score (P<0.05). The female patients had a lower score than the male patients (P<0.05), especially in the emotional function domain (P=0.002). Different disease distributions were not statistically significant in the IBDQ total score (P=0.183).

Conclusions

UC has a negative influence on HRQOL. HRQOL in patients with moderate UC was lower than HRQOL in patients with mild UC, as measured by the IBDQ. UC disease activity has a negative correlation with HRQOL. Gender and the disease activity index are important factors involved in the impairment of HRQOL in Chinese patients with UC. Chinese females may benefit from increased psychological care as part of UC therapy.

Association between genetic polymorphisms in interferon regulatory factor 5 (IRF5) gene and Malaysian patients with Crohn's disease

OBJECTIVE

The study aimed to investigate the association between the interferon regulatory factor 5 (IRF5) gene polymorphisms and the onset of Crohn's disease (CD) in a Malaysian cohort.

METHODS

Genomic DNA was extracted from blood samples collected from 91 CD patients and 100 healthy individuals via a conventional phenol-chloroform extraction method. Screening of the four target single nucleotide polymorphisms (SNPs), including rs3807306, rs4728142, rs10954213 and rs11770589 was carried out in a real-time polymerase chain reaction (PCR) thermal cycler using TaqMan genotyping assay. The genetic data obtained was subsequently subjected to statistical analysis to relate the SNPs to the onset of CD in the Malaysian population. The genotyping assay and data were further validated selectively by conventional PCR amplification of the SNP sites and DNA sequencing.

RESULTS

The rs3807306 G allele was a risk factor for CD (OR 2.3630, P = 0.00004), whereas the homozygous T genotype was protective against the disease (OR 0.2038, P = 0.00004). The heterozygous A/G genotype of rs10954213 was significantly associated with CD (OR 4.319, P = 0.0377). On the other hand, the homozygous A and heterozygous A/G genotypes of the rs11770589 were significant in the controls (OR 0.4242, P = 0.0166) and patients (OR 2.000, P = 0.0179), respectively. In the ethnic-stratification analysis, the rs11770589 homozygous A genotype was protective in Indians (OR 0.1551, P = 0.0112).

CONCLUSION

IRF5 gene polymorphisms may play a role in the development of CD in the Malaysian population.

Differences in clinical features of Crohn's disease and intestinal tuberculosis

AIM: To investigate the clinical features of Crohn’s disease (CD) and intestinal tuberculosis (ITB) with a scoring system that we have developed.

METHODS: A total of 25 CD and 40 ITB patients were prospectively enrolled from August 2011 to July 2012. Their characteristics and clinical features were recorded. Laboratory, endoscopic, histologic and radiographic features were determined. The features with a high specificity were selected to establish a scoring system. The features supporting CD scored +1, and those supporting ITB scored -1; each patient received a final total score. A receiver operating characteristic (ROC) curve was used to determine the best cut-off value for distinguishing CD from ITB.

RESULTS: Based on a high specificity of differentiating between CD and ITB, 12 features, including longitudinal ulcers, nodular hyperplasia, cobblestone-like mucosa, intestinal diseases, intestinal fistula, the target sign, the comb sign, night sweats, the purified protein derivative test, the interferon-γ release assay (T-SPOT.TB), ring ulcers and ulcer scars, were selected for the scoring system. The results showed that the average total score of the CD group was 3.12 ± 1.740, the average total score of the ITB group was -2.58 ± 0.984, the best cutoff value for the ROC curve was -0.5, and the diagnostic area under the curve was 0.997, which was statistically significant (P < 0.001). The patients whose total scores were higher than -0.5 were diagnosed with CD; otherwise, patients were diagnosed with ITB. Overall, the diagnostic accuracy rate and misdiagnosis rate of this scoring system were 97% and 3%, respectively.

CONCLUSION: Some clinical features are valuable for CD and ITB diagnosis. The described scoring system is key to differentiating between CD and ITB.

Emerging leadership lecture: Inflammatory bowel disease in Asia: emergence of a "Western" disease

More than a decade ago, inflammatory bowel disease (IBD) is rare in Asia. Today, the importance of IBD in Asia is exemplified by its rapidly increasing incidence, complicated disease behavior, and substantial morbidity. In the first large-scale population-based epidemiologic study in Asia, the incidence of IBD varied from 0.60 to 3.44 per 100,000. There has been a twofold to threefold increase in the incidence of IBD in several countries in Asia. Ulcerative colitis (UC) is more prevalent than Crohn's disease (CD), although CD incidence is rapidly increasing. A positive family history is much less common than in the West, as are extra-intestinal disease manifestations. Complicated and penetrating CD are common in Asia. These epidemiologic changes may relate to increased contact with the West, westernization of diet, improved hygiene, increasing antibiotics use, or changes in the gut microbiota. Asian patients with CD have altered gut microbiota compared with their healthy counterparts and Caucasian CD subjects. Mucosa-associated microbiota in IBD may differ geographically. In a population-based case-control study, breast-feeding, having pets, and better sanitary conditions were protective of IBD, suggesting that childhood environment plays an important role in modulating disease development. Genetic factors also differ between Asians and Caucasians. Nucleotide oligomerization domain-2 (NOD2) and autophagy variants were not associated with CD, but tumor necrosis factor superfamily gene-15 polymorphisms were strongly associated with CD in East Asians. Research in Asia, an area of rapidly changing IBD epidemiology, may lead to the discovery of critical etiologic factors that lead to the development of IBD.

Protective association of tumor necrosis factor superfamily 15 (TNFSF15) polymorphic haplotype with Ulcerative Colitis and Crohn's disease in an Indian population

Background

Tumor necrosis factor superfamily (TNFSF) proteins are involved in the genesis of inflammatory bowel disease (IBD). We examined the association of seven single nucleotide polymorphisms (SNP) in the TNFSF15 gene with Crohn's disease (CD) and ulcerative colitis (UC) in the Indian population.

Methods

Seven SNPs in the TNFSF15 gene (rs10114470, rs3810936, rs6478108, rs4263839, rs6478109, rs7848647 and rs7869487) were genotyped in 309 CD patients, 330 UC patients and 437 healthy controls using the Sequenom iPLEX MassArray platform. Disease associations were evaluated for allelotypes and for genotypes.

Results

The minor T alleles and the TT genotypes of rs10114470 and rs3810936 were significantly protectively associated with both CD and UC. The CC genotype of rs6478108, AA genotype of rs4263839, the AA genotype of rs6478109, the TT genotype of rs7848647 and the CC genotype of rs7869487 were all protectively associated with CD but not with UC. Two haplotype blocks could be discerned, one where SNPs rs10114470 and rs3810936 were in tight LD (D′ = 0.8) and the other where rs6478108, rs4263839, rs6478109, rs7848647 and rs7869487 were in tight LD (D′ 0.92–1.00). The second block of haplotypes were not associated with CD or with UC. The first block of haplotypes was very significantly associated with both CD and UC.

Conclusions

Strong associations exist between TNFSF15 gene polymorphisms and IBD (both CD and UC) in the Indian population.

A questionnaire-based survey on the diagnosis and management of inflammatory bowel disease in East Asian countries in 2012

BACKGROUND AND AIM

The prevalence and incidence of inflammatory bowel disease (IBD) are lower in East Asia than in Western countries; however, marked increases have recently been reported. The clinical diagnosis and medical management of IBD in East Asia differ from those in Western countries. A questionnaire-based survey was performed to gather physicians' current opinions on IBD in different East Asian countries.

METHODS

Representative International Gastrointestinal Consensus Symposium (IGICS) committee members provided a questionnaire to physicians in each East Asian country studied. The questionnaire mainly focused on the diagnosis and management of IBD.

RESULTS

There were 19 respondents from Japan, 10 from South Korea, 9 from the Philippines, 6 from China and 4 from Indonesia. Colonoscopy (100%) and histopathology (63%) were commonly used for the diagnosis in ulcerative colitis (UC). Conventional small bowel enteroclysis was still the most common diagnostic tool for assessing small bowel lesions in Crohn's disease (CD) in East Asia. The percentage of physicians who investigated the reactivation of Cytomegalovirus in severe or refractory patients with UC ranged from 0% in the Philippines and Indonesia to 100% in Japan and Korea. Most physicians in Korea, the Philippines, China and Indonesia chose thiopurines or anti-TNF therapy as the second-line treatment in severe refractory UC, whereas Japanese physicians preferred to use tacrolimus or leukocyte apheresis. Physicians in the Philippines and Indonesia preferred to use oral 5-aminosalicylic acid for newly diagnosed severe ileocecal CD. In contrast, Korean physicians chose oral steroids and most physicians in China and Japan preferred to use anti-TNF. Nutritional therapy to induce or maintain remission in patients with CD was commonly used in Indonesia, Japan and China. Targeted biopsies by conventional colonoscopy were the most preferred strategy for cancer surveillance in long-standing UC over random biopsies in this region.

CONCLUSIONS

The present survey found that current diagnostic approaches and clinical management of IBD vary within East Asian countries.

Association of IRGM gene mutations with inflammatory bowel disease in the Indian population

BACKGROUND

Mutations in the IRGM gene have been associated with Crohn's disease in several populations but have not been explored in Indian patients with this disease. This study examined the association of IRGM mutations with ulcerative colitis and Crohn's disease in Indian patients with inflammatory bowel disease.

METHODS

The IRGM gene was amplified in four segments and Sanger-sequenced in 101 participants (42 Crohn's disease, 39 ulcerative colitis, and 20 healthy controls). Ten single nucleotide polymorphisms (SNP) were genotyped in 1200 participants (352 Crohn's disease, 400 ulcerative colitis, and 448 healthy controls) using Sequenom MassARRAY iPLEX. Disease associations were evaluated for each of the ten SNPs.

RESULTS

Thirty one mutations were identified in the IRGM gene, of which two had not hitherto been reported (150226250- ss947429272 & 150227858- ss947429273). Ten SNPs (6 from the above and 4 from the literature) were evaluated. Significant associations with Crohn's disease were noted with the T allele of rs1000113 (OR 1.46, 95% CI 1.12-1.90), T allele of rs9637876 (OR 1.25, 95% CI 1.005-1.561) and C allele of rs 13361189 (OR 1.33, 95% CI 1.07-1.669). Two SNPs--rs11747270 and rs180802994--did not exhibit Hardy-Weinberg equilibrium but were associated with both Crohn's disease and ulcerative colitis in this population. The remaining SNPs did not show significant associations with either Crohn's disease or ulcerative colitis.

CONCLUSIONS

Association of IRGM gene SNPs with Crohn's disease is reported for the first time in Indian patients. We also report, for the first time, an association of rs 9637876 in the IRGM gene with Crohn's disease.

Characteristics of fecal and mucosa-associated microbiota in Chinese patients with inflammatory bowel disease

The intestinal microbiota plays an important role in the pathogenesis of inflammatory bowel disease (IBD), and geographical and genetic backgrounds impact the composition of the intestinal microbiota. However, there is a lack of evidence regarding the overall changes and characteristics of fecal-associated microbiota (FAM) and mucosa-associated microbiota (MAM) in Chinese patients with IBD. We recruited 26 patients with Crohn's disease (CD), 46 patients with ulcerative colitis (UC), and 21 healthy individuals; we collected matched fresh fecal and mucosal samples from the same subjects. The microbial communities were studied by 454-pyrosequencing. Community-wide changes in FAM and MAM were observed in patients with IBD. The proportion of several butyrate-producing bacteria, such as of the genera Roseburia, Coprococcus, and Ruminococcus were significantly reduced, whereas the pathogens Escherichia-Shigella and Enterococcus were prevalent in patients with IBD. FAM and MAM were similar between CD and UC. FAM differed from MAM in healthy individuals and patients with UC. In conclusion, the compositions of FAM and MAM were altered in patients with IBD. The reduction of butyrate-producing bacteria and the increase in opportunistic pathogens might be associated with the pathogenesis of IBD.

Association between STAT3 gene polymorphisms and Crohn's disease susceptibility: a case-control study in a Chinese Han population

Background

Crohn’s disease (CD) is an immune-related disease with genetic predisposition. This study aimed to investigate the association of three polymorphisms in the signal transducer and activator of transcription 3 (STAT3) gene with CD risk in a Chinese population.

Methods

We conducted a hospital-based case–control study involving 232 CD patients and 272 controls. Genotyping was performed using polymerase chain reaction with sequence-specific primer method. Statistical analyses were conducted using logistic regression and genotype risk scoring.

Results

Significant differences were found between patients and controls in allele/genotype distributions of rs744166 (Pallele = 0.0008; Pgenotype = 0.003) and allele distributions of rs4796793 (P = 0.03). The risk for CD associated with the rs744166-A mutant allele decreased by 37% [95% confidence interval (CI): 0.48–0.83] under the additive model, 39% (95% CI: 0.43–0.81) under the dominant model and 57% (95% CI: 0.24–0.77) under the recessive model. Carriers of the rs4796793-G mutant allele exhibited 25% (95% CI: 0.58–0.98; P = 0.03) and 47% (95% CI: 0.30–0.95) decreased risks of developing CD under the additive and recessive models, respectively.

Conclusions

STAT3 rs744166 and rs4796793 polymorphisms may be associated with CD occurrence and used as a predictive factor of CD in Chinese Han populations.

Virtual Slides

The virtual slide(s) for this article can be found here: http://diagnosticpathology.slidepath.com/webViewer.php?snapshotId=1297687014

Routine diagnosis of intestinal tuberculosis and Crohn's disease in Southern India

AIM: To investigate whether routinely measured clinical variables could aid in differentiating intestinal tuberculosis (ITB) from Crohn’s disease (CD).

METHODS: ITB and CD patients were prospectively included at four South Indian medical centres from October 2009 to July 2012. Routine investigations included case history, physical examination, blood biochemistry, ileocolonoscopy and histopathological examination of biopsies. Patients were followed-up after 2 and 6 mo of treatment. The diagnosis of ITB or CD was re-evaluated after 2 mo of antituberculous chemotherapy or immune suppressive therapy respectively, based on improvement in signs, symptoms and laboratory variables. This study was considered to be an exploratory analysis. Clinical, endoscopic and histopathological features recorded at the time of inclusion were subject to univariate analyses. Disease variables with sufficient number of recordings and P < 0.05 were entered into logistic regression models, adjusted for known confounders. Finally, we calculated the odds ratios with respective confidence intervals for variables associated with either ITB or CD.

RESULTS: This study included 38 ITB and 37 CD patients. Overall, ITB patients had the lowest body mass index (19.6 vs 22.7, P = 0.01) and more commonly reported weight loss (73% vs 38%, P < 0.01), watery diarrhoea (64% vs 33%, P = 0.01) and rural domicile (58% vs 35%, P < 0.05). Endoscopy typically showed mucosal nodularity (17/31 vs 2/37, P < 0.01) and histopathology more frequently showed granulomas (10/30 vs 2/35, P < 0.01). The CD patients more frequently reported malaise (87% vs 64%, P = 0.03), nausea (84% vs 56%, P = 0.01), pain in the right lower abdominal quadrant on examination (90% vs 54%, P < 0.01) and urban domicile (65% vs 42%, P < 0.05). In CD, endoscopy typically showed involvement of multiple intestinal segments (27/37 vs 9/31, P < 0.01). Using logistic regression analysis we found weight loss and nodularity of the mucosa were independently associated with ITB, with adjusted odds ratios of 8.6 (95%CI: 2.1-35.6) and 18.9 (95%CI: 3.5-102.8) respectively. Right lower abdominal quadrant pain on examination and involvement of ≥ 3 intestinal segments were independently associated with CD with adjusted odds ratios of 10.1 (95%CI: 2.0-51.3) and 5.9 (95%CI: 1.7-20.6), respectively.

CONCLUSION: Weight loss and mucosal nodularity were associated with ITB. Abdominal pain and excessive intestinal involvement were associated with CD. ITB and CD were equally common.

Early predictors of responses and clinical outcomes of corticosteroid treatment for severe ulcerative colitis

BACKGROUND

Patients with severe ulcerative colitis (SUC) have a high risk of requiring colectomy or resorting to a second-line treatment. However, neither clinical outcomes nor factors predictive of poor response have been clearly established in the treatment of SUC.

OBJECTIVE

To assess prospectively the effects and predictors of corticosteroids (CS) use in clinical outcomes of SUC during 1 year of follow-up.

MATERIAL AND METHODS

Consecutive inpatients with SUC, who had been treated with intravenous CS, were enrolled. Patients were monitored by clinical, laboratory, and endoscopic examinations, and the data were recorded for 1 year. Univariate and multivariate analyses were performed at 1 week.

RESULTS

There were 22.6% (14/62) nonresponders at 7 days. Several predictors were associated with nonresponse to CS. These included Mayo Score at baseline (p = 0.007), partial Mayo Score, number of bowel movements, blood presence in stool, abdominal pain, and levels of C-reactive protein (CRP), hemoglobin (Hgb), platelet count (PLT), and erythrocyte sedimentation rate (ESR) on day 3 (p < 0.05). Multiple logistic regression analysis identified the Partial Mayo Score at day 3 as an independent predictor of outcome (p = 0.012). A total of 12 patients underwent colectomy within 1 year. The short-term response rates to intravenous cyclosporin (CsA) and infliximab (IFX) in SUC were 71.4% (5/7) and 77.8% (7/9), respectively.

CONCLUSIONS

Many patients with SUC eventually became refractory to or dependent on CS. The Mayo score and laboratory characteristics were factors useful in predicting short-term outcome of CS treatment. Secondary medical therapy can help avoid emergency surgery.

Fluorescent quantitative PCR of Mycobacterium tuberculosis for differentiating intestinal tuberculosis from Crohn's disease

Intestinal tuberculosis (ITB) and Crohn's disease (CD) are granulomatous disorders with similar clinical manifestations and pathological features that are often difficult to differentiate. This study evaluated the value of fluorescent quantitative polymerase chain reaction (FQ-PCR) for Mycobacterium tuberculosis (MTB) in fecal samples and biopsy specimens to differentiate ITB from CD. From June 2010 to March 2013, 86 consecutive patients (38 females and 48 males, median age 31.3 years) with provisional diagnoses of ITB and CD were recruited for the study. The patients' clinical, endoscopic, and histological features were monitored until the final definite diagnoses were made. DNA was extracted from 250 mg fecal samples and biopsy tissues from each patient. The extracted DNA was amplified using FQ-PCR for the specific MTB sequence. A total of 29 ITB cases and 36 CD cases were included in the analysis. Perianal disease and longitudinal ulcers were significantly more common in the CD patients (P<0.05), whereas night sweats, ascites, and circumferential ulcers were significantly more common in the ITB patients (P<0.05). Fecal FQ-PCR for MTB was positive in 24 (82.8%) ITB patients and 3 (8.3%) CD patients. Tissue PCR was positive for MTB in 16 (55.2%) ITB patients and 2 (5.6%) CD patients. Compared with tissue FQ-PCR, fecal FQ-PCR was more sensitive (X2=5.16, P=0.02). We conclude that FQ-PCR for MTB on fecal and tissue samples is a valuable assay for differentiating ITB from CD, and fecal FQ-PCR has greater sensitivity for ITB than tissue FQ-PCR.

Inflammatory bowel disease: an expanding global health problem

This review provides a summary of the global epidemiology of inflammatory bowel diseases (IBD). It is now clear that IBD is increasing worldwide and has become a global emergence disease. IBD, which includes Crohn’s disease (CD) and ulcerative colitis (UC), has been considered a problem in industrial-urbanized societies and attributed largely to a Westernized lifestyle and other associated environmental factors. Its incidence and prevalence in developing countries is steadily rising and has been attributed to the rapid modernization and Westernization of the population. There is a need to reconcile the most appropriate treatment for these patient populations from the perspectives of both disease presentation and cost. In the West, biological agents are the fastest-growing segment of the prescription drug market. These agents cost thousands of dollars per patient per year. The healthcare systems, and certainly the patients, in developing countries will struggle to afford such expensive treatments. The need for biological therapy will inevitably increase dramatically, and the pharmaceutical industry, healthcare providers, patient advocate groups, governments and non-governmental organizations should come to a consensus on how to handle this problem. The evidence that IBD is now affecting a much younger population presents an additional concern. Meta-analyses conducted in patients acquiring IBD at a young age also reveals a trend for their increased risk of developing colorectal cancer (CRC), since the cumulative incidence rates of CRC in IBD-patients diagnosed in childhood are higher than those observed in adults. In addition, IBD-associated CRC has a worse prognosis than sporadic CRC, even when the stage at diagnosis is taken into account. This is consistent with additional evidence that IBD negatively impacts CRC survival. A continuing increase in IBD incidence worldwide associated with childhood-onset of IBD coupled with the diseases’ longevity and an increase in oncologic transformation suggest a rising disease burden, morbidity, and healthcare costs. IBD and its associated neoplastic transformation appear inevitable, which may significantly impact pediatric gastroenterology and adult CRC care. Due to an infrastructure gap in terms of access to care between developed vs. developing nations and the uneven representation of IBD across socioeconomic strata, a plan is needed in the developing world regarding how to address this emerging problem.

Granulomas of intestinal tuberculosis and Crohn's disease can be differentiated by CD73 cell surface marker expression: a pilot study

BACKGROUND

Intestinal tuberculosis (ITB) and Crohn's disease are similar granulomatous disorders. Granulomas are present in both and difficult to differentiate on histopathology alone. A recent study demonstrated recruitment of mesenchymal cells (MSCs) at the periphery of granulomas in lymph node tuberculosis which suppressed T cell responses. We hypothesized that granulomas of ITB would also recruit MSCs to evade host immune response.

AIM

The purpose of this study was to demonstrate MSC markers in granulomas of ITB and evaluate whether distribution of MSC markers could differentiate between granulomas of Crohn's and ITB.

METHODS

We initially retrospectively enrolled 17 patients with confirmed ITB (8) or Crohn's (9) with granulomas on histopathology. Tissues were evaluated by immunofluorescence for MSC markers CD29, CD90, CD73 and absence of haematopoietic markers CD31, CD34, CD45 and CD14. Double-staining was done to confirm presence of MSCs. Subsequently, 23 postoperative specimens of Crohn's (18) and ITB (5) were analyzed for validation.

RESULTS

Overall, 27 Crohn's and 13 ITB cases were assessed. CD29 and CD90 positive cells were noted around both ITB and Crohn's granulomas. MSC marker CD73 was expressed around the granulomas of ITB alone and was completely absent in the Crohn's. The subsequent assessment of granulomas in postoperative specimens of Crohn's and ITB also showed similar results.

CONCLUSION

Granulomas of ITB and Crohn's disease can be differentiated by CD73 MSC surface marker expression. The differential CD73 expression around ITB granuloma indicates that Mycobacterium tuberculosis evades host immunity by recruiting MSCs with CD73 expression. MSCs with increased CD73 expression could be the future for therapeutic intervention in Crohn's.

Hypothesis: Increased consumption of emulsifiers as an explanation for the rising incidence of Crohn's disease

Crohn's disease (CD) incidence has increased over the past fifty years but the explanation is unclear. CD can be brought into remission by liquid enteral feeding, but the mechanism for this response is unknown. We suggest that consumption of emulsifiers in processed foods may promote CD by increasing bacterial translocation. This is supported by evidence that (i) geographical variation in CD correlates with emulsifier consumption as does the increasing incidence of CD in Japan; (ii) although CD incidence also correlates with fat consumption, the response to enteral feeding is not affected by the fat content of the feed and (iii) very small concentrations of the emulsifier polysorbate 80 enhance bacterial translocation across intestinal epithelia. Undigested emulsifiers may increase bacterial translocation, particularly in the small intestine where the mucus layer is discontinuous. The hypothesis should be testable by trials of enteral feeding with/without emulsifiers.

Clostridium leptum group bacteria abundance and diversity in the fecal microbiota of patients with inflammatory bowel disease: a case-control study in India

Background

Alterations in the fecal bacterial flora occur in inflammatory bowel disease (IBD). We examined the abundance and diversity of Clostridium leptum group, an important group of carbohydrate-fermenting bacteria, in the feces of patients with IBD and compared them with healthy controls.

Methods

Seventeen healthy controls (HC), 20 patients with Crohn’s disease (CD) and 22 patients with ulcerative colitis (UC) participated in the study. DNA extracted from fecal samples was amplified by PCR targeting 16S rRNA gene sequences specific to C. leptum group. The PCR product was subjected to temporal temperature gradient electrophoresis (TTGE) and the number and position of individual bands were noted and diversity was estimated. The identity of bands at different positions was confirmed by cloning and sequencing. Real time quantitative PCR with Mesa Green, targeted at specific 16S rRNA gene sequences, was used to quantitate C. leptum group and its most prominent constituent, Faecalibacterium prausnitzii.

Results

Twenty five different operational taxonomic units (OTUs, equivalent to species) were identified constituting the C. leptum group in these participants. Their sequences were deposited in GenBank [accession numbers GQ465348 to GQ465370]. OTU number was significantly reduced in CD (7.7±3.7, mean±SD) and UC (9.0±3.0) compared to HC (11.9±2.2) (P=0.0005). The Simpson D index of alpha diversity was not significantly different between the three groups. Total numbers of C. leptum group bacteria and F. prausnitzii were reduced in both CD and UC compared to HC (P=0.0036 and P<0.0001 respectively). Disease activity did not influence numbers of C. leptum or F. prausnitzii in patients with CD or UC.

Conclusion

C. leptum numbers and diversity were significantly reduced in both CD and UC suggesting that alterations noted were not specific to one disease. This could contribute to reduced short chain fatty acid production in IBD.

Survey of inflammatory bowel diseases in India

INTRODUCTION

Inflammatory bowel disease (IBD), both ulcerative colitis (UC) and Crohn's disease (CD), once thought to be uncommon, is now seen commonly in India. The Indian Society of Gastroenterology (ISG) Task Force on IBD decided to collate data on the clinical spectrum of IBD currently prevailing in India.

METHODS

An open call to members of ISG was given through publication of a proforma questionnaire in the Indian Journal of Gastroenterology and the web portal of ISG. The proforma contained questions related with demographic features, family history, risk factors, clinical manifestations and characteristics, course of disease, and pattern of treatment of IBD.

RESULTS

Of 1,255 filled questionnaires received, 96 were rejected and 1,159 (92.3 %) were analyzed. This comprised data on 745 (64.3 %) patients with UC, 409 (35.3 %) with CD, and 5 with indeterminate colitis. The median duration of illness was longer in patients with CD (48 months) compared to those with UC (24 months) (p = 0.002). More than one half of patients (UC 51.6 %, CD 56.9 %) had one or more extraintestinal symptoms. A definite family history of IBD was present in 2.9 % (UC 2.3 % and CD 4.6 %; p = 0.12). The extent of disease in UC was pancolitis 42.8 %, left-sided colitis 38.8 %, and proctitis alone in 18.3 %. The extent of disease involvement in CD was both small and large intestine in 39.6 %, colon alone in 31.4 % and small intestine alone in 28.9 %. Stricturing and fistulizing disease were noted in 18.8 % and 4.4 % of patients with CD respectively. Chronic continuous and intermittent disease course were present in 35.5 % and 47.2 % of UC patients respectively, and in 23.1 % and 68.8 % of CD patients. Four percent of patients with UC had undergone colectomy, while 15.2 % of patients with CD underwent surgical intervention.

CONCLUSIONS

The present survey provides a reasonable picture of the demographic features and clinical manifestations of Indian patients with IBD, their risk factors, course of disease, and the treatment given to them.

Mitochondrial electron transport chain complex dysfunction in the colonic mucosa in ulcerative colitis

BACKGROUND

Ulcerative colitis (UC) is characterized by an energy deficiency state of the colonic epithelium. This study evaluated mitochondrial electron transport chain (ETC) complex activity in normal and disease mucosa in patients with UC. Alterations in ETC complexes were also investigated in experimental colitis in mice.

METHODS

Biopsies were obtained from macroscopically normal and diseased colonic mucosa of 43 patients with UC and 35 controls undergoing screening colonoscopy and ETC complex activity was assayed biochemically. ETC complex activities were also assayed in colonic epithelial cells isolated from Swiss albino mice with dextran sodium sulfate (DSS)-induced colitis at various stages of induction of colitis. Mucosal nitrite levels and protein carbonyl content were determined.

RESULTS

The activity of Complex II was significantly decreased in colonic biopsies from UC patients compared with controls, while activities of other mitochondrial complex were normal. Complex II activity was equally decreased in diseased and normal mucosa in UC; the degree of reduction did not correlate with clinical, endoscopic, or histological grading of disease activity. In DSS-fed mice, a reduction in activity of Complex IV and Complex II was observed. Activity of other complex was not affected. Administration of aminoguanidine, an inducible nitric oxide synthase (iNOS) inhibitor, attenuated all parameters of colitis as well as the reductions in Complex IV and Complex II activity.

CONCLUSIONS

Reduction in Complex II activity appears to be a specific change in UC, present in quiescent and active disease. Mitochondrial complex dysfunction occurs in DSS colitis in mice and appears to be mediated by nitric oxide.

NOD2 gene mutations associate weakly with ulcerative colitis but not with Crohn's disease in Indian patients with inflammatory bowel disease

BACKGROUND

Three mutations (two missense and one frameshift) in the NOD2 gene are associated with Crohn's disease (CD) in a proportion of patients with Crohn's disease in North America, Europe and Australia. These three mutations are not found in Indian patients with CD. We undertook new studies to identify polymorphisms in the NOD2 gene in the Indian population and to detect whether any of these were associated with inflammatory bowel disease (IBD) in this population.

METHODS

Individual exons of the NOD2 gene were amplified by PCR and subjected to denaturing high performance liquid chromatography (DHPLC) to detect heteroduplex formation. All 12 exons of the NOD2 gene were amplified and Sanger-sequenced to detect polymorphisms in the NOD2 gene. 310 patients with CD, 318 patients with ulcerative colitis (UC) and 442 healthy controls (HC) were recruited for association studies. DNA from these participants was evaluated for the identified eight polymorphisms by Sequenom analysis.

RESULTS

Heteroduplex formation was noted by DHPLC in exons 2 and 4 of the NOD2 gene. Sequencing of the entire NOD2 gene data revealed eight polymorphisms - rs2067085, rs2066842, rs2066843, rs1861759, rs2111235, rs5743266, rs2076753, and rs5743291 - of which the latter four were described for the first time in Indians. None of these polymorphisms was associated with CD. The SNPs rs2066842 and rs2066843 were in significant linkage disequilibrium. Both SNPs showed a significant association with UC (P=0.03 and 0.04 respectively; odds ratio 1.44 and 1.41 respectively).

CONCLUSION

Four NOD2 polymorphisms were identified for the first time in the Indian population. Of 8 NOD2 polymorphisms, none were associated with CD but two were weakly associated with UC. NOD2 polymorphisms do not play a major role in CD genesis in India.

[Guidelines for the management of ulcerative colitis]

Ulcerative colitis (UC) is a chronic inflammatory bowel disorder characterized by a relapsing and remitting course. The quality of life can decreases significantly during exacerbations of the disease. The incidence and prevalence of UC in Korea are still lower than those of Western countries, but have been rapidly increasing during the past decades. Various medical and surgical therapies are currently used for the management of UC. However, many challenging issues exist and sometimes these lead to differences in practice between clinicians. Therefore, Inflammatory Bowel Diseases (IBD) Study Group of Korean Association for the Study of Intestinal Diseases (KASID) set out the Korean guidelines for the management of UC. These guidelines are made by the adaptation using several foreign guidelines and encompass treatment of active colitis, maintenance of remission and indication for surgery in UC. The specific recommendations are presented with the quality of evidence. These are the first Korean treatment guidelines for UC and will be revised with new evidences on treatment of UC.

Molecular alterations in colitis-associated colorectal neoplasia: study from a low prevalence area using magnifying chromo colonoscopy

BACKGROUND AND AIM

Longstanding ulcerative colitis (UC) predisposes to colorectal cancer (CRC). To understand the molecular pathogenesis of colitis-associated colorectal neoplasia (UC-CRN), we studied the frequency of microsatellite instability (MSI) and mutations in p53, BRAF and KRAS genes in the tissues of patients with long standing UC with or without neoplasia and compared them with colitis patients without risk of neoplasia, and those with sporadic colorectal neoplasia (S-CRN) in an area with lower prevalence for either disease.

METHODS

Biopsies were obtained during magnifying chromo colonoscopy or routine colonoscopy in consecutive UC patients with high risk (UC-HR) and low risk (UC-LR) of neoplasia, and those with S-CRN. MSI (NCI-Bethesda panel) and mutations in p53, KRAS and BRAF genes were analysed.

RESULTS

Twenty-eight patients with UC-HR, 30 with UC-LR and 30 with S-CRN were included. Six (21.4%) of UC-HR had neoplasia (Progressors). MSI was not detected in the UC-CRN group as compared to 5 (16.7%) in the S-CRN group. p53 mutations occurred in 1 (3.3%) of UC-LR, increasing to 6 (27.3%, P<0.05) and 3 (50%, P<0.05) in the UC-HR subgroups without and with neoplasia respectively, as against 10 (33.3%) in sporadic neoplasia group. KRAS mutations were found only in the presence of neoplasia. None showed the BRAF mutation.

CONCLUSIONS

In a population with a lower prevalence for UC and CRC, the molecular pathogenesis of colitis-associated colorectal neoplasia is comparable to that reported from areas with a higher prevalence of these diseases, MSI being an exception.

Comparison of clinical characteristics and management of inflammatory bowel disease in Hong Kong versus Melbourne

BACKGROUND AND AIM

Inflammatory bowel disease (IBD), common in Melbourne, was rare but is now increasing in incidence in Hong Kong (HK). To investigate whether these are the same diseases in the West and East, potential causes of changing incidence, and to plan resource needs, an appreciation of clinical characteristics in contrasting populations is essential.

METHODS

Disease characteristics were collected from prospectively populated IBD databases in two specialist centers in Melbourne, Australia and HK.

RESULTS

Of 795 patients (Crohn's disease [CD] : ulcerative colitis [UC] Melbourne 272:159 and HK 161:203), the age of diagnosis was higher, there were proportionally more male patients with CD but no UC sex difference, fewer patients were current or ex-smokers (CD 8% vs 50%; UC 17% vs 35%) and a family history of IBD was less common (2% vs 11%; P < 0.001) in HK compared to Melbourne. Stricturing and perianal CD were more common in HK (12% vs 6%; P < 0.001; and 29% vs 16%; P = 0.001, respectively). In HK for UC, more patients had extensive disease at diagnosis (42% vs 22%) but colectomy was less common (7% vs 20%; P < 0.001). In Melbourne there was greater steroid use at diagnosis and patients were more likely to receive an immunomodulator or anti-tumor necrosis factor agent.

CONCLUSIONS

IBD in HK was diagnosed at an older age, and had more complicated disease behavior than in Melbourne. Medical therapy, however, was less intense in HK. These differences may relate to real differences in disease or delayed diagnosis due to late presentation and less disease recognition in HK.

Systems analysis of inflammatory bowel disease based on comprehensive gene information

Background

The rise of systems biology and availability of highly curated gene and molecular information resources has promoted a comprehensive approach to study disease as the cumulative deleterious function of a collection of individual genes and networks of molecules acting in concert. These "human disease networks" (HDN) have revealed novel candidate genes and pharmaceutical targets for many diseases and identified fundamental HDN features conserved across diseases. A network-based analysis is particularly vital for a study on polygenic diseases where many interactions between molecules should be simultaneously examined and elucidated. We employ a new knowledge driven HDN gene and molecular database systems approach to analyze Inflammatory Bowel Disease (IBD), whose pathogenesis remains largely unknown.

Methods and Results

Based on drug indications for IBD, we determined sibling diseases of mild and severe states of IBD. Approximately 1,000 genes associated with the sibling diseases were retrieved from four databases. After ranking the genes by the frequency of records in the databases, we obtained 250 and 253 genes highly associated with the mild and severe IBD states, respectively. We then calculated functional similarities of these genes with known drug targets and examined and presented their interactions as PPI networks.

Conclusions

The results demonstrate that this knowledge-based systems approach, predicated on functionally similar genes important to sibling diseases is an effective method to identify important components of the IBD human disease network. Our approach elucidates a previously unknown biological distinction between mild and severe IBD states.

Preparation of a mouse model of TNBS-induced ulcerative colitis: technology improvement and optimal dose exploration

AIM: To establish a mouse model of 2, 4, 6-trinitrobenzenesulfonic acid (TNBS)-induced colitis using the "gavage needle" instead of "silicone tube", and to explore the optimal dosage and induction time of TNBS.

METHODS: Forty SPF male Balb/c mice were randomly and equally divided into five groups: normal control group and four TNBS groups (treated with 37.5, 75, 150, and 200 mg/kg of TNBS). Four mice in each group were killed on days 2 and 4 after model induction to observe the physical status and evaluate pathologic changes in the colon.

RESULTS: No death occurred during the "gavage needle"-based modeling preparation. The control group showed no abnormalities. Higher doses of TNBS induced more severe congestion, hemorrhage, edema, inflammation and ulcer in the colon mucosa. Colonic tissue edema, inflammatory cell infiltration, goblet cell deletion, and formation of ulcer were aggravated significantly as the dosage of TNBS increased. The above mentioned features recovered from day 2 after model induction in mice treated with 37.5 and 75 mg/kg of TNBS, but showed no obvious alterations on day 4 after model induction in mice treated with 150 and 200 mg/kg of TNBS.

CONCLUSION: The "gavage needle"-based method could improve efficiency and increase stability in preparing the mouse model of TNBS-induced ulcerative colitis.

Haplotype-based analysis of ulcerative colitis risk loci identifies both IL2 and IL21 as susceptibility genes in Han Chinese

BACKGROUND

The incidence of ulcerative colitis (UC) varies between Western and Eastern ethnicities. A distinct genetic background may play a role in the differences. Until now, very little was known of the UC genetics in Asian populations. Here we performed a haplotype-based analysis of six known UC susceptibility loci in Han Chinese patients.

METHODS

In all, 245 UC patients and 300 healthy controls of Han Chinese descent were genotyped for 27 single nucleotide polymorphisms (SNPs), which cover the major haplotypes of the chromosome regions containing IL10, IL2/IL21, MYO9B, ECM1, MST1, and IL23R in Han Chinese.

RESULTS

In contrast to the tight linkage disequilibrium (LD) block of the IL2/IL21 region in Caucasians, IL2 and IL21 reside in two independent LD blocks in Han Chinese. The IL2 SNP rs2069762 (P = 7.0 × 10(-4) , odds ratio [OR] = 1.54, 95% confidence interval [CI] 1.20-1.99) and the IL21 SNP rs2055979 (P = 1.2 × 10(-4) , OR = 1.50, 95% CI 1.17-1.92) were independently associated with UC. We identified one risk haplotype in IL2 and another independent risk haplotype in IL21. In addition to the IL2/IL21 locus, we observed association of the TT genotype of SNP rs1545620 in MYO9B with UC (P = 0.0169; OR = 0.29, 95% CI 0.11-0.78) and association of rs17375018 in IL23R with pancolitis in Chinese UC patients (P = 0.002; OR = 2.38, 95% CI 1.41-4.02).

CONCLUSIONS

Our study confirmed the association of the IL2/IL21 region with UC in Han Chinese patients, and further implied both IL2 and IL21 as genetic risk factors for UC. Han Chinese UC patients share part of their genetic susceptibility with Caucasian patients.

Environmental factors associated with Crohn's disease in India

BACKGROUND

The frequency of diagnosis of Crohn's disease (CD) in India is increasing. This case-control study was designed to detect associations of environmental and dietary factors with the diagnosis of CD.

METHODS

In 200 consecutive patients with CD and 200 control subjects without gastrointestinal disease, environmental hygiene exposures in childhood and in the past one year, and dietary preferences were recorded using a questionnaire. Univariate and multivariate analyses were done.

RESULTS

In univariate analysis, CD showed positive association with urban residence (at birth and current), availability of protected drinking water (childhood and current), availability of piped water in the house (childhood and current), and strict vegetarian dietary habit, and negative association with regular fish consumption and presence of cattle in the house compound. Multivariate analysis showed that regular fish consumption (OR 0.52, 95% CI 0.33-0.80, p = 0.003), and presence of cattle in the house compound currently (OR 0.57, 95% CI 0.35-0.92, p = 0.023) were significant protective associations, whereas use of safe drinking water was positively associated (OR 1.59, 95% CI 1.02-2.47, p = 0.042) with the disease.

CONCLUSION

Occurrence of CD was associated with dietary and environmental exposures, which indicate that diet and hygiene may influence the development of this disease.