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Inflammatory bowel disease includes two major types of disease: Crohn’s disease and ulcerative colitis. The incidence of inflammatory bowel disease is increasing worldwide, including in Korea. This chronic disease progresses gradually, with cycles of improvement and exacerbation. Therefore, a quick diagnosis and appropriate treatment are necessary. In this review, we discuss the clinical symptoms of inflammatory bowel disease, as well as diagnostic methods.

Background Several studies have shown that there are no significant differences in anastomotic leakage associated with Transanal total mesorectal excision (taTME) versus laparoscopic TME (lapTME) for rectal cancer; however, little is known about late anastomotic leakage, such as that primarily found in the chronic presacral sinus. We aimed to compare the occurrence of anastomotic leakage and chronic presacral sinus in rectal cancer for taTME and lapTME. Methods In this retrospective cohort study, data were collected for patients with rectal cancer who underwent surgery between January 2009 and September 2019. Of the 220 patients included in this study, 182 were in the lapTME group and 38 in the taTME group. We compared factors associated with anastomotic leakage and chronic presacral sinus formation between the two groups. A binary-logistic model was used to determine the risk factors for chronic presacral sinus. Results Anastomotic leakage occurred in six patients (15.8%) in the taTME group and 36 patients (19.7%) in the lapTME group. Chronic presacral sinus occurred in three patients (7.9%) in the taTME group and 15 patients (8.2%) in the lapTME group. There was no significant difference in anastomotic leakage or chronic presacral sinus between groups (P = 0.569 and P = 1.000, respectively). Pathologic stage III or higher was significantly associated with chronic presacral sinus formation (P = 0.006). Conclusion There were no significant differences between taTME and lapTME regarding the incidence of anastomotic leakage or chronic presacral sinus. Almost one-third of anastomotic leakages developed into chronic presacral sinus.

Background. Patients with inflammatory bowel disease (IBD) have a decreased quality of life (QoL), the improvement of which is a treatment goal. The CUCQ-8 is a verified simple and effective QoL measurement tool. We validated the Korean version of CUCQ-8 with the approval of its developer. Methods. We investigated the correlation between the Korean version of CUCQ-8 and the IBDQ-32 in patients with IBD. Results. In all, 147 subjects (male, 97 (66.0%); female, 50 (34.0%); mean age 36.2 ± 13.5 years) were analyzed. Cronbach’s alpha coefficient of the CUCQ-8 was 0.833, indicating very high internal consistency. The Korean version of the CUCQ-8 showed a significant correlation with the IBDQ-32 and its subscales (correlation coefficient, >0.75). Conclusions. The Korean version of the CUCQ-8 has high reliability and construct validity and can be used to evaluate the QoL of patients with IBD.

Background/Aims: This study assessed the efficacy and safety of adalimumab (ADA) and explored predictors of response in Korean patients with ulcerative colitis (UC).Methods: A prospective, observational, multicenter study was conducted over 56 weeks in adult patients with moderately to severely active UC who received ADA. Clinical response, remission, and mucosal healing were assessed using the Mayo score.Results: A total of 146 patients were enrolled from 17 academic hospitals. Clinical response rates were 52.1% and 37.7% and clinical remission rates were 24.0% and 22.0% at weeks 8 and 56, respectively. Mucosal healing rates were 39.0% and 30.1% at weeks 8 and 56, respectively. Prior use of anti-tumor necrosis factor-α (anti-TNF-α) did not affect clinical and endoscopic responses. The ADA drug level was significantly higher in patients with better outcomes at week 8 (P

Although gut microbiome dysbiosis has been associated with inflammatory bowel disease (IBD), the relationship between the oral microbiota and IBD remains poorly understood. This study aimed to identify unique microbiome patterns in saliva from IBD patients and explore potential oral microbial markers for differentiating Crohn’s disease (CD) and ulcerative colitis (UC). A prospective cohort study recruited IBD patients (UC: n = 175, CD: n = 127) and healthy controls (HC: n = 100) to analyze their oral microbiota using 16S rRNA gene sequencing. Machine learning models (sparse partial least squares discriminant analysis (sPLS-DA)) were trained with the sequencing data to classify CD and UC. Taxonomic classification resulted in 4041 phylotypes using Kraken2 and the SILVA reference database. After quality filtering, 398 samples (UC: n = 175, CD: n = 124, HC: n = 99) and 2711 phylotypes were included. Alpha diversity analysis revealed significantly reduced richness in the microbiome of IBD patients compared to healthy controls. The sPLS-DA model achieved high accuracy (mean accuracy: 0.908, and AUC: 0.966) in distinguishing IBD vs. HC, as well as good accuracy (0.846) and AUC (0.923) in differentiating CD vs. UC. These findings highlight distinct oral microbiome patterns in IBD and provide insights into potential diagnostic markers.

Although fatigue is common in patients with inflammatory bowel disease (IBD), it often goes unrecognized and untreated. We investigated the degree of fatigue and associated factors in patients with IBD. A multicenter study involving 147 IBD patients was conducted at five academic hospitals from August 2019 to December 2021. Fatigue was evaluated using the validated Korean version of the Multidimensional Fatigue Inventory (MFI-K). Among 97 ulcerative colitis patients and 50 Crohn’s disease patients, the mean total MFI-K score was 59.0 ± 5.5, which corresponded to a moderate-to-severe level of fatigue. Moderate-to-severe disease activity was found to be significantly associated with a higher general and physical fatigue subscale MFI-K score compared to remission-to-mild disease activity (17.6 ± 1.7 vs. 16.7 ± 2.0, p = 0.009), while the use of biologics was associated with a lower total MFI-K score (57.3 ± 5.0 vs. 59.5 ± 5.5, p = 0.031). In multiple linear regression, the total MFI-K score was positively correlated with a history of surgery for IBD, while it was negatively correlated with the use of biologics. Depression was positively correlated with the reduced motivation subscale score. The degree of fatigue in patients with IBD was high. Disease activity, the use of biologics, a history of surgery for IBD, and depression were associated with fatigue.

Background: Inflammatory bowel disease (IBD) is a multifactorial chronic inflammatory disease resulting from dysregulation of the mucosal immune response and gut microbiota. Crohn's disease (CD) and ulcerative colitis (UC) are difficult to distinguish, and differential diagnosis is essential for establishing a long-term treatment plan for patients. Furthermore, the abundance of mucosal bacteria is associated with disease severity. This study aimed to differentiate and diagnose these two diseases using the microbiome and identify specific biomarkers associated with disease activity. Results: We observed differences in the abundance and composition of the microbiome between patients with IBD and healthy controls (HC). Compared to HC, the diversity of the gut microbiome in patients with IBD decreased; the diversity of the gut microbiome in patients with CD was significantly lower. We identified 68 members of the microbiota (28 for CD and 40 for UC) associated with these diseases. Additionally, as the disease progressed through different stages, the diversity of the bacteria decreased. The abundances of Alistipes shahii and Pseudodesulfovibrio aespoeensis were negatively correlated with the severity of CD, whereas the abundance of Polynucleobacter wianus was positively correlated. The severity of UC was negatively correlated with the abundance of A. shahii, Porphyromonas asaccharolytica and Akkermansia muciniphilla, while it was positively correlated with the abundance of Pantoea candidatus pantoea carbekii. A regularized logistic regression model was used for the differential diagnosis of the two diseases. The area under the curve(AUC) was used to examine the model performance. The model discriminated between UC and CD at an AUC of 0.886 (training set) and 0.826 (test set) and an area under the precision-recall curve (AUCPR) of 0.871 (test set). Conclusions: Based on fecal whole-metagenome shotgun (WMS) sequencing, CD and UC were diagnosed using a machine-learning predictive model. Additionally, microbiome biomarkers associated with disease activity (UC and CD) have been proposed.

Background and AimsCrohn’s disease (CD) has a complex polygenic etiology with high heritability. We keep putting an effort to identify novel variants associated with susceptibility to CD through a genome-wide association study (GWAS) in large Korean populations.MethodsGenome-wide variant data from 902 Korean patients with CD and 72,179 controls were used to assess the genetic associations in a meta-analysis with previous Korean GWAS results from 1,621 patients with CD and 4,419 controls. Epistatic interactions between CD-risk variants of interest were tested using a multivariate logistic regression model with an interaction term.ResultsWe identified two novel genetic associations with the risk of CD nearZBTB38and within the leukocyte immunoglobulin-like receptor (LILR) gene cluster (P−8), with highly consistent effect sizes between the two independent Korean cohorts. CD-risk variants in the LILR locus are known quantitative trait loci (QTL) for multiple LILR genes, of whichLILRB2directly interacts with various ligands including MHC class I molecules. The LILR lead variant exhibited a significant epistatic interaction with CD-associated regulatory variants forTAP2involved in the antigen presentation of MHC class I molecules (P=4.11×10−4), showing higher CD-risk effects of theTAP2variant in individuals carrying more risk alleles of the LILR lead variant (OR=0.941,P=0.686 in non-carriers; OR=1.45,P=2.51×10−4in single-copy carriers; OR=2.38,P=2.76×10−6in two-copy carriers).ConclusionsThis study demonstrated that genetic variants at two novel susceptibility loci and the epistatic interaction between variants in LILR andTAP2loci confer risk of CD.

Background/Aims: Our study aimed to evaluate the long-term outcomes and risk factors for relapse after anti-tumor necrosis factor (TNF)-α cessation in inflammatory bowel disease (IBD) patients because they are not well established. Methods: A retrospective multicenter cohort study was conducted involving patients with Crohn’s disease (CD) or ulcerative colitis (UC) from 10 referral hospitals in Korea who discontinued firstline anti-TNF therapy after achieving clinical remission. Results: A total of 109 IBD patients (71 CD and 38 UC) with a median follow-up duration of 56 months were analyzed. The cumulative relapse rates at 1, 3, and 5 years were 11.3%, 46.7%, and 62.5% for CD patients and 28.9%, 45.3%, and 60.9% for UC patients. Multivariable Cox analysis revealed that discontinuation owing to the clinician’s decision was associated with lower risk of relapse (vs patient’s preference: hazard ratio [HR], 0.13; 95% confidence interval [CI], 0.04 to 0.48; p=0.002) and adalimumab use was associated with higher risk of relapse (vs infliximab: HR, 4.42; 95% CI, 1.24 to 17.74; p=0.022) in CD patients. Mucosal healing was associated with lower risk of relapse (vs nonmucosal healing: HR, 0.12; 95% CI, 0.02 to 0.83; p=0.031) in UC patients. Anti-TNF re-induction was provided to 52 patients, and a response was obtained in 50 patients. However, 25 of them discontinued retreatment owing to a loss of response (n=15), the patient’s preference (n=6), and other factors (n=4). Conclusions: More than 60% of IBD patients in remission under anti-TNF therapy relapsed within 5 years of treatment cessation. Anti-TNF re-induction was effective. However, half of the patients discontinued anti-TNF therapy, and 50% of these patients discontinued treatment owing to loss of response. (Gut Liver 2021;15:752-762)

Almost half of patients show no primary or secondary response to monoclonal anti-tumor necrosis factor α (anti-TNF) antibody treatment for inflammatory bowel disease (IBD). Thus, the exact mechanisms of a non-durable response (NDR) remain inadequately defined. We used our genome-wide genotype data to impute expression values as features in training machine learning models to predict a NDR. Blood samples from various IBD cohorts were used for genotyping with the Korea Biobank Array. A total of 234 patients with Crohn’s disease (CD) who received their first anti-TNF therapy were enrolled. The expression profiles of 6294 genes in whole-blood tissue imputed from the genotype data were combined with clinical parameters to train a logistic model to predict the NDR. The top two and three most significant features were genetic features (DPY19L3, GSTT1, and NUCB1), not clinical features. The logistic regression of the NDR vs. DR status in our cohort by the imputed expression levels showed that the β coefficients were positive for DPY19L3 and GSTT1, and negative for NUCB1, concordant with the known eQTL information. Machine learning models using imputed gene expression features effectively predicted NDR to anti-TNF agents in patients with CD.

Background and Aim. This study evaluated the impact of coronavirus disease 2019 (COVID-19) on the mental health of inflammatory bowel disease (IBD) patients. We quantified anxiety, depression, and medication adherence among IBD patients through a single-center survey in South Korea during the COVID-19 pandemic. Methods. An electronic survey was made available to patients at the IBD clinic in Daejeon St. Mary’s hospital from July 2021 to September 2021. The validated Hospital Anxiety and Depression Scale (HADS) was used to assess depression and anxiety. The Korean version of the Medication Adherence Rating Scale (KMARS) questionnaire was used to assess medication adherence. Results. In total, 407 patients (56.5%; ulcerative colitis, 43.5%; Crohn’s disease) participated in the survey. Among the respondents, 14.5% showed significant anxiety and 26.3% showed significant depression. Female sex, presence of mental disease, unvaccinated status, and the presence of Crohn’s disease were associated with greater risks of anxiety and depression. Among medications, immunomodulators were associated with a greater risk of anxiety. In terms of KMARS, patients reported favorable medication adherence despite the psychological burden of the pandemic. The KMARS score was 7.3 ± 1.5 (mean ± SD) of 10.0 points. High anxiety and depression were associated with a slight decrease in medication adherence. Conclusions. COVID-19 has increased anxiety and depression among IBD patients, whose medication adherence has nevertheless remained good. Furthermore, anxiety and depression were found to have a negative correlation with adherence. Our results provide insights concerning psychological response and medication adherence among IBD patients in South Korea during the COVID-19 pandemic.

Background: Tofacitinib is a small molecule that inhibits Janus kinase and has been reported to be effective in Western patients with ulcerative colitis (UC). However, the real-life data on tofacitinib in Asian UC patients are limited. Objective: To investigate the real-life effectiveness and safety of tofacitinib induction and maintenance treatment in Korean patients with UC. Design: This was a retrospective study on patients with UC who received tofacitinib treatment at 12 hospitals in Korea between January 2018 and November 2020. Methods: Clinical remission at week 52, defined as a partial Mayo score of ⩽2 with a combined rectal bleeding subscore and stool frequency subscore of ⩽1, was used as the primary outcome. Adverse events (AEs), including herpes zoster and deep vein thrombosis, were also evaluated. Results: A total of 148 patients with UC were started on tofacitinib. Clinical remission rates of 60.6%, 54.9%, and 52.8% were reported at weeks 16, 24, and 52, respectively. Clinical response rates of 71.8%, 67.6%, and 59.9% were reported at weeks 16, 24, and 52, respectively. Endoscopic remission rates at weeks 16 and 52 were 52.4% and 30.8% based on the Mayo endoscopic subscore and 20.7% and 15.2% based on the UC endoscopic index of severity (UCEIS), respectively. A higher UCEIS at baseline was negatively associated with clinical response [adjusted odds ratio (aOR): 0.774, p = 0.029] and corticosteroid-free clinical response (aOR: 0.782, p = 0.035) at week 52. AEs occurred in 19 patients (12.8%) and serious AEs in 12 patients (8.1%). Herpes zoster occurred in four patients (2.7%). One patient (0.7%) suffered from deep vein thrombosis. Conclusions: Tofacitinib was an effective induction and maintenance treatment with an acceptable safety profile in Korean patients with UC. Plain language summary Real-life effectiveness and safety of tofacitinib treatment in Korean patients with ulcerative colitis Ulcerative colitis (UC) is an idiopathic, chronic inflammatory disorder of the colonic mucosa that usually presents with bloody diarrhea and abdominal pain. Tofacitinib is a small molecule that inhibits Janus kinase and has been reported to be effective in Western patients with UC. However, real-life data on the effectiveness of tofacitinib in Asian patients with UC are limited. To investigate the real-life effectiveness and safety of tofacitinib treatment in Korean patients with UC, we retrospectively analyzed the data of 148 patients with UC who received tofacitinib treatment at 12 hospitals in Korea between January 2018 and November 2020. Clinical remission (i.e. complete improvement of symptoms) was achieved in 60.6% and 52.8% of patients at weeks 16 and 52, respectively. Endoscopic remission was achieved in 52.4% and 30.8% of patients at weeks 16 and 52, respectively. A higher baseline score of the UC endoscopic index of severity, which is one of the endoscopic indices that evaluate the severity of inflammation of the colon, was negatively associated with clinical response (i.e. partial improvement of symptoms). Adverse events (AEs) including herpes zoster and deep vein thrombosis occurred in 19 patients (12.8%) and serious AEs occurred in 12 patients (8.1%). Our real-life study shows that tofacitinib is a clinically effective treatment for Korean patients with UC, and the incidence of AEs was also similar to those observed in other real-world studies.

Background: Therapeutic targets for ulcerative colitis (UC) and prediction models of antitumor necrosis factor (TNF) therapy outcomes have not been fully reported. Objective: Investigate the characteristic metabolite and lipid profiles of fecal samples of UC patients before and after adalimumab treatment and develop a prediction model of clinical remission following adalimumab treatment. Design: Prospective, observational, multicenter study was conducted on moderate-to-severe UC patients ( n = 116). Methods: Fecal samples were collected from UC patients at 8 and 56 weeks of adalimumab treatment and from healthy controls (HC, n = 37). Clinical remission was assessed using the Mayo score. Metabolomic and lipidomic analyses were performed using gas chromatography mass spectrometry and nano electrospray ionization mass spectrometry, respectively. Orthogonal partial least squares discriminant analysis was performed to establish a remission prediction model. Results: Fecal metabolites in UC patients markedly differed from those in HC at baseline and were changed similarly to those in HC during treatment; however, lipid profiles did not show these patterns. After treatment, the fecal characteristics of remitters (RM) were closer to those of HC than to those of non-remitters (NRM). At 8 and 56 weeks, amino acid levels in RM were lower than those in NRM and similar to those in HC. After 56 weeks, levels of 3-hydroxybutyrate, lysine, and phenethylamine decreased, and dodecanoate level increased in RM similarly to those in HC. The prediction model of long-term remission in male patients based on lipid biomarkers showed a higher performance than clinical markers. Conclusion: Fecal metabolites in UC patients markedly differ from those in HC, and the levels in RM are changed similarly to those in HC after anti-TNF therapy. Moreover, 3-hydroxybutyrate, lysine, phenethylamine, and dodecanoate are suggested as potential therapeutic targets for UC. A prediction model of long-term remission based on lipid biomarkers may help implement personalized treatment.

Crohn’s disease (CD) and ulcerative colitis (UC) can be difficult to differentiate. As differential diagnosis is important in establishing a long-term treatment plan for patients, we aimed to develop a machine learning model for the differential diagnosis of the two diseases using RNA sequencing (RNA-seq) data from endoscopic biopsy tissue from patients with inflammatory bowel disease (n = 127; CD, 94; UC, 33). Biopsy samples were taken from inflammatory lesions or normal tissues. The RNA-seq dataset was processed via mapping to the human reference genome (GRCh38) and quantifying the corresponding gene models that comprised 19,596 protein-coding genes. An unsupervised learning model showed distinct clusters of four classes: CD inflammatory, CD normal, UC inflammatory, and UC normal. A supervised learning model based on partial least squares discriminant analysis was able to distinguish inflammatory CD from inflammatory UC after pruning the strong classifiers of normal CD vs. normal UC. The error rate was minimal and affected only two components: 20 and 50 genes for the first and second components, respectively. The corresponding overall error rate was 0.147. RNA-seq analysis of tissue and the two components revealed in this study may be helpful for distinguishing CD from UC.

Background/Aims: In ulcerative colitis (UC) patients, Escherichia coli Nissle 1917 (EcN) is equivalent to mesalazine for preventing disease relapse; however, evidence of the ability of EcN to increase health-related quality of life or induce remission remains scarce. We investigated the efficacy of EcN as an add-on therapy for UC.Methods: In this multicentre, double-blind, randomised, placebo-controlled study, a total of 133 UC patients were randomly assigned to receive either EcN or placebo once daily for 8 weeks. Inflammatory bowel disease questionnaire (IBDQ) scores (primary endpoint) and clinical remission and response rates (secondary endpoints) were compared (Clinical trial registration number: NCT04969679).Results: In total, 118 patients (EcN, 58; placebo, 60) completed the study. The number of patients reaching the primary endpoint did not differ between the EcN and placebo groups (30 [51.7%] vs. 31 [51.7%]; per-protocol analysis, p = 1.0; intention-to-treat analysis, p = 0.86). However, significantly fewer patients in the EcN group exhibited a decreased IBDQ score (1 [1.7%] vs. 8 [13.3%]; per-protocol analysis, p = 0.03; intention- to-treat analysis, p = 0.02). Moreover, a significantly higher number of patients in the EcN group displayed clinical response at 4 weeks (23 [39.7%] vs. 13 [21.7%], p = 0.04) and endoscopic remission at 8 weeks (26 [46.4%] vs. 16 [27.1%], p = 0.03).Conclusions: Although the number of patients reaching the primary endpoint did not differ between the EcN and placebo groups, EcN was found to be safe and effective in preventing the exacerbation of IBDQ scores and achieving clinical responses and endoscopic remission in patients with mild-to-moderate UC.

BACKGROUND: Colectomy risk after acute severe ulcerative colitis (ASUC) has not been compared between Eastern and Western countries. We compared the 1-year colectomy risk after ASUC between Korea and the USA. METHODS: Data on patients admitted for ASUC to five tertiary referral hospitals in Korea and Mount Sinai Hospital, New York, the USA, between January 2015 and January 2019 were reviewed retrospectively. For comparability between groups, a 1:1 propensity score matching (PSM) was performed. The primary outcome was colectomy, and secondary outcomes were mortality, readmission, and venous thromboembolism (VTE) within 1-year of the index admission for ASUC. The risk of each outcome was compared using Cox proportional hazards model in pre-matched cohort and Kaplan–Meier analysis with log-rank test in post-matched cohort. RESULTS: 290 ASUC patients were included in the study (121 Korea, 169 the USA). After PSM, 56 patients were selected in each group with no significant differences in baseline variables. At 1 year after ASUC, colectomy was less common in Korea than in the USA [3 (5.4%) vs. 24 (42.9%), p < 0.001]. The cumulative colectomy risk was significantly higher in the USA than in Korea in pre-matched cohort [adjusted hazard ratio 7.89, 95% confidence interval 3.23 to 19.22] and in post-matched cohort (log-rank p < 0.001), while there was no difference in cumulative risk of mortality, readmission, and VTE. CONCLUSION: Colectomy risk within 1 year of ASUC is significantly higher in the USA than in Korea. We observed no differences in mortality, readmission, and VTE between the two groups.

Aim: This study examined the real-world effectiveness and safety outcomes of vedolizumab in ulcerative colitis (UC) patients who had failed anti-tumor necrosis factor (anti-TNF) therapy in Korea. Methods: A retrospective chart review study was conducted in adults with moderate to severely active UC who had failed anti-TNF agents and subsequently received vedolizumab. Clinical response and clinical remission at week 6 and 14 after vedolizumab initiation was evaluated. Safety outcomes were also reported. Outcome rates were compared with a matched sub-cohort derived from the open-label sub-cohort of the GEMINI 1 trial using the optimal matching method. Results: A total of 105 patients (mean age, 45.3 years; 63.8% male) were included. At week 6, 55.8% ( n = 43/77) achieved a clinical response and 18.2% ( n = 14/77) achieved clinical remission. At week 14, 73.2% ( n = 52/71) achieved a clinical response and 39.4% ( n = 28/71) achieved clinical remission. When non-response imputation was used, the clinical response rate at week 6 and week 14 were 40.1% ( n = 43/105) and 49.5% ( n = 52/105) respectively. Of the 105 patients, 16 (15.2%) experienced at least one adverse event. The matched analysis showed that the clinical response rate at week 6 was higher in the matched sub-cohort of this study (24/47, 51.1%) versus the matched sub-cohort from the GEMINI 1 open-label cohort (12/47, 34.3%, p = 0.019). The clinical remission rates at week 6 were similar (7/47, 14.9% versus 9/47, 19.1%, p = 0.785). Conclusions: In the real-world setting, vedolizumab is effective and well tolerated within the first 14 weeks of use in Korea. The proportion of patients experiencing clinical response and clinical remission at 6 and 14 weeks appeared to be largely consistent with that observed in real-world studies from other regions and populations.

One-liter polyethylene glycol plus ascorbic acid (PEG-ASC) improves patient tolerability, but some patients still show low tolerability to a relatively high content of ASC. This study aimed to improve the tolerability and safety of 1-L PEG with low-dose ASC in comparison with standard 1-L and 2-L PEG-ASC.This was a randomized, controlled, double-blinded, multicenter, noninferiority trial involving 215 healthy adults who underwent colonoscopy from June 2020 to January 2021. Efficacy, tolerability, and safety were compared among 1-L PEG with low-dose ASC (50% lower ASC concentration in group A and 25% lower ASC concentration in groups B and C) and standard 1-L and 2-L PEG-ASC with all split regimens.One-liter PEG with low-dose ASC (groups A-C) had similar bowel cleansing efficacies according to the Harefield Cleansing Scale and Boston Bowel Preparation Scale, without negative clinical performance, compared with standard 1-L and 2-L PEG-ASC preparation (all P.1). One-liter PEG with low-dose ASC had better tolerability compared with 2-L PEG-ASC and less residual fluid retention in the stomach compared with 1-L PEG-ASC, proportional to the amount of ASC. No significant differences were found in the incidences of overall adverse events, mild adverse events, or death or in the occurrence of gastroduodenal erosion or ulcer in upper endoscopy.One-liter PEG with low-dose ASC (25%-50% reduction in dose) for bowel cleansing showed similar efficacy and safety compared with standard 1-L or 2-L PEG-ASC, better tolerability compared with 2-L PEG-ASC, and less residual gastric fluid retention compared with standard 1-L PEG-ASC. (Clinical trial registration number: KCT0005490.).

Perforation is the most serious adverse event of colonoscopy, but rarely considered from the view of colonoscopists’ second victim experience and perception discordance between colonoscopists and patients. We aimed to evaluate colonoscopists’ second victim experience and the perception discordance between colonoscopists and patients for the colonoscopic perforation. A survey for colonoscopic perforation was performed for the colonoscopists and outpatients who visited the university hospital between February 1, 2020, and April 30, 2020. The questionnaire included questions regarding colonoscopists’ satisfaction for the intervention strategies offered to patients and patient–colonoscopist perception on colonoscopic perforation. A modified Korean version of the “Second Victim Experience and Support Tool (K-SVEST)” was used to assess the second victim experiences and supportive resources for the colonoscopists. Survey results from 160 colonoscopists and 165 patients were analyzed. The colonoscopists’ satisfaction scores were higher for strategies related to sufficient explanation, empathy, courteous listening, and monetary compensation. The scores of the K-SVEST for the second victim experience were highest in psychological distress, followed by loss of professional self-efficacy, colleague support, physical distress, non-work-related support, institutional support, and turnover intentions/absenteeism. Significant patient–colonoscopist discordance was noted for the same colonoscopic perforation scenario on the judgment of medical error, health professionals’ apology, monetary compensation, and criminal penalties for the colonoscopists. Colonoscopists can suffer emotionally and physically from the second victim experience after colonoscopic perforation. In addition, the significant patient–colonoscopist discordance should be considered to make a better communication for the colonoscopic perforation.

The hepatobiliary system is one of the most common sites of extraintestinal manifestation in patients with inflammatory bowel disease (IBD). The progression of IBD can lead to a primary hepatobiliary manifestation and can occur secondary to multiple drugs or accompanying viral infections. Primary sclerosing cholangitis is the representative hepatobiliary manifestation of IBD, particularly in ulcerative colitis. Although most agents used in the treatment of IBD are potentially hepatotoxic, the risk of serious hepatitis or liver failure is low. The prevalence of HBV and HCV in IBD is similar to the general population, but the clinical concern is HBV reactivation associated with immunosuppressive therapy. Patients undergoing cytotoxic chemotherapy or immunosuppressive therapy with a moderate to high risk of HBV reactivation require prophylactic antiviral therapy. On the other hand, HCV has little risk of reactivation. Patients with IBD are more likely to have nonalcoholic fatty liver disease than the general population and tend to occur at younger ages. IBD and cholelithiasis are closely related, especially in Crohn's disease.

Background We investigated the real-life effectiveness and safety of vedolizumab (VDZ) induction therapy among Korean patients with Crohn disease (CD) or ulcerative colitis (UC) for whom anti-tumor necrosis factor therapy previously failed. Methods Adult patients who started VDZ induction therapy at 16 centers were prospectively enrolled in the Korean VDZ nationwide registry. The coprimary outcomes were clinical remission, defined as a Crohn’s Disease Activity Index score Results Between August 2017 and November 2019, a total of 158 patients (80 with CD and 78 with UC) received VDZ induction therapy. Clinical remission rates among patients with CD and patients with UC were 44.1% and 44.0%, respectively. Among patients with UC, the endoscopic remission rate was 32.4%. Clinical response and remission rates showed increasing trends during induction therapy. Multivariable analysis revealed that clinical response at week 6 was the only predictor of clinical remission at week 14 for both patients with CD and patients with UC. Among patients who experienced 1 or more adverse events (n = 71; 44.9%), disease exacerbation (n = 28; 17.7%) was the most common adverse event. Conclusions Among Korean patients with CD or UC for whom anti-tumor necrosis factor therapy failed, VDZ induction therapy was effective and safe. The early clinical response was associated with clinical remission after VDZ induction therapy.

Limited studies have examined the intestinal microbiota composition in relation to Crohn&rsquo, s disease (CD) prognosis. We analyzed the differences in microbial communities and relevant metabolic pathways associated with prognostic variables in patients with CD. We applied 16S rRNA gene sequencing to analyze a cohort of 1110 CD and healthy control (HC) fecal samples. We categorized patients with CD into good (CD-G), intermediate (CD-I) and poor (CD-P) prognosis groups, according to the history of using biologics and intestinal resection. Microbiota &alpha, diversity decreased more in CD-P than CD-G and CD-I. Microbiota &szlig, diversity in CD-P differed from that in CD-G and CD-I. Thirteen genera and 10 species showed differential abundance between CD-G and CD-P groups. Escherichia coli (p = 0.001) and species Producta (p = 0.01) and genera Lactobacillus (p = 0.003) and Coprococcus (p = 0.01) consistently showed differences between CD-G and CD-P groups after adjusting for confounding variables. Functional profiling suggested that the microbial catabolic pathways and pathways related to enterobacterial common antigen and lipopolysaccharide biosynthesis were better represented in the CD-P group than in the CD-G group, and E. coli were the top contributors to these pathways. CD prognosis is associated with altered microbiota composition and decreased diversity, and E. coli might be causally involved in CD progression, and may have adapted to live in inflammatory environments.

Backgrounds and Aims We aimed to evaluate the safety of Bacille Calmette–Guérin [BCG] vaccination in infants born to mothers receiving anti-tumour necrosis factor [anti-TNF] therapy for inflammatory bowel disease. Methods Adverse events of BCG vaccination were evaluated in 90 infants who were last exposed to anti-TNF agents at a median of gestational week 30. Results After receiving BCG vaccination at a median age of 6 months [range, 0.25–11 months], three infants [3.3%] showed injection site swelling, two of whom also showed axillar lymphadenopathy. The rates of adverse events were similar between infants who were last exposed to anti-TNF agents before the third trimester [n = 35] and those who were last exposed in the third trimester [n = 55] [2.9% vs 3.6%; p = 1.00]. All adverse events were spontaneously resolved and there were no serious adverse events such as active tuberculosis infection or death. Conclusions BCG vaccination after 6 months of age is of low risk in infants exposed to anti-TNF agents in utero.

Crohn's disease and ulcerative colitis are the two major types of inflammatory bowel disease, and affect mainly the gastrointestinal tract but also have extraintestinal sequelae, such as arterial and venous thromboembolism. Thromboembolic complications, particularly pulmonary thromboembolism, can be life threatening and require prompt management with anticoagulants. Conventional vitamin K antagonists have been used for the treatment of thromboembolic complications, but the development of novel oral anticoagulants has shifted the paradigm. We report a case of a 42-year-old female with ulcerative colitis who experienced an acute flare-up due to cytomegalovirus superinfection with pulmonary thromboembolism. She was treated with oral mesalamine, intravenous steroid and ganciclovir and low-molecular-weight heparin, followed by rivaroxaban, a novel oral anticoagulant. Her symptoms resolved after treatment, and no recurrence was noted during a 6-month post-treatment follow-up.

PURPOSE Dysregulated microRNAs (miRNAs) can contribute to cancer development by leading to abnormal proliferation of cells, apoptosis, and differentiation. Although several miRNAs that are related to gastric cancer have been identified, the reported results have been inconsistent. The aim of this study was to determine miRNA expression profiles and validate miRNAs up- and down-regulated in gastric cancer. MATERIALS AND METHODS We evaluated 34 primary gastric cancer tissues and paired adjacent nontumorous gastric tissues. Total RNA was extracted, and low-molecular-weight RNAs (

We propose graphene as a Schottky metal electrode material for an AlGaN/GaN heterostructure layer-based metal–insulator–semiconductor–insulator–metal (MISIM)-type UV sensor. The fabricated AlGaN/GaN MISIM UV sensor showed two distinguishable sensing windows, namely, a UV-A and a UV-B region with sharp cutoff characteristic. The graphene-electrode UV sensor had a lower dark current density and better UV-to-visible rejection ratio than that of a Ni-electrode UV sensor.