Usefulness of texture and color enhancement imaging in assessing mucosal healing in patients with ulcerative colitis.

BACKGROUND AND AIMS: Endoscopic remission is known to be defined as a Mayo endoscopic subscore (MES) of ≤1 in patients with ulcerative colitis (UC). However, some individuals experience relapse even after showing endoscopic remission under white-light imaging (WLI), and no tool exists that can detect these individuals. The aim of this study was to clarify the usefulness of texture and color enhancement imaging (TXI) in the assessment of inflammation in patients with UC. METHODS: This was a prospective, single-arm, observational study conducted at a university hospital. From January 2021 to December 2021, 146 UC patients with endoscopic remission were enrolled. Images were evaluated by WLI, TXI, and pathologic evaluation, followed by prognostic studies. The primary endpoint of the study was the cumulative relapse of UC in each TXI score. The secondary endpoints were the association between TXI and pathologic scores, predictors of relapse, and interobserver agreement between the MES and TXI scores. RESULTS: Patients with TXI score 2 had significantly lower UC relapse-free rates than did those with TXI scores 0-1 (log-rank test, P < .01). When pathologic remission was defined as Matts grade ≤2, the rate of pathologic remission decreased significantly with higher TXI scores (P = .01). In multivariate analysis, TXI score 2 was the only risk factor for UC relapse (P < .01; hazard ratio, 4.16; 95% confidence interval, 1.72-10.04). Interobserver agreement on the TXI score was good (κ = 0.597-0.823). CONCLUSION: TXI can be used to identify populations with poor prognosis in MES 1, for whom treatment intensification has been controversial.

Amino acid position 37 of HLA-DRß1 affects susceptibility to Crohn's disease in Asians.

Crohn's disease (CD) and ulcerative colitis (UC) are the major types of chronic inflammatory bowel disease (IBD) characterized by recurring episodes of inflammation of the gastrointestinal tract. Although it is well established that human leukocyte antigen (HLA) is a major risk factor for IBD, it is yet to be determined which HLA alleles or amino acids drive the risks of CD and UC in Asians. To define the roles of HLA for IBD in Asians, we fine-mapped HLA in 12 568 individuals from Korea and Japan (3294 patients with CD, 1522 patients with UC and 7752 controls). We identified that the amino acid position 37 of HLA-DRß1 plays a key role in the susceptibility to CD (presence of serine being protective, P = 3.6 × 10-67, OR = 0.48 [0.45-0.52]). For UC, we confirmed the known association of the haplotype spanning HLA-C*12:02, HLA-B*52:01 and HLA-DRB1*1502 (P = 1.2 × 10-28, OR = 4.01 [3.14-5.12]).

Long-term retention of adalimumab treatment and associated prognostic factors for 1189 patients with Crohn's disease.

BACKGROUND AND AIM: There are few studies on the long-term efficacy of adalimumab treatment for patients with Crohn's disease. We have conducted a large, multicenter, retrospective cohort study to evaluate the long-term retention rate and prognostic factors associated with the discontinuation of adalimumab treatment in patients with Crohn's disease. METHODS: Data were collected from all patients with Crohn's disease who had received at least one induction dose of 160 mg of adalimumab between October 2010 and December 2013 at 41 institutions. The cumulative retention rates of adalimumab treatment following the first administration were estimated using the Kaplan-Meier method. Prognostic factors related to the cumulative retention rates were evaluated by log-rank tests and multivariate Cox regression analysis. RESULTS: A total of 1189 patients were included in the study. The 1-, 2-, 3-, and 4-year cumulative retention rates of adalimumab were 81%, 72%, 65%, and 62%, respectively. The multivariate Cox regression analysis confirmed female sex, previous infliximab use, perianal disease, concomitant treatment with prednisolone at baseline, higher C-reactive protein levels, and lower albumin levels as significant independent predictors of poor retention rate of adalimumab treatment. Significantly, more female patients than male patients discontinued adalimumab because of adverse events, especially skin reactions, infections, and arthralgia. CONCLUSIONS: Our data demonstrated a good retention rate of adalimumab in patients with Crohn's disease over a 4-year period. Female sex, perianal disease, concomitant treatment with prednisolone at baseline, previous infliximab use, higher C-reactive protein levels, and lower albumin levels were associated with poor retention of adalimumab treatment.

Disease susceptibility genes shared by primary biliary cirrhosis and Crohn's disease in the Japanese population.

We previously identified TNFSF15 as the most significant susceptibility gene at non-HLA loci for both primary biliary cirrhosis (PBC) and Crohn's diseases (CD) in the Japanese population. The aim of this study is to identify further disease susceptibility genes shared by PBC and CD. We selected 15 and 33 genetic variants that were significantly associated with PBC and CD, respectively, based on previously reported genome-wide association studies of the Japanese population. Next, an association study was independently performed for these genetic variants in CD (1312 CD patients and 3331 healthy controls) and PBC (1279 PBC patients and 1015 healthy controls) cohorts. Two CD susceptibility genes, ICOSLG rs2838519 and IL12B rs6556412, were also nominally associated with susceptibility to PBC (P=3.85 × 10(-2) and P=8.40 × 10(-3), respectively). Three PBC susceptibility genes, CXCR5 rs6421571, STAT4 rs7574865 and NFKB1 rs230534, were nominally associated with susceptibility to CD (P=2.82 × 10(-2), P=3.88 × 10(-2) and P=2.04 × 10(-2), respectively). The effect of ICOSLG and CXCR5 variants were concordant but the effect of STAT4, NFKB1 and IL12B variants were discordant for PBC and CD. TNFSF15 and ICOSLG-CXCR5 might constitute a shared pathogenic pathway in the development of PBC and CD in the Japanese population, whereas IL12B-STAT4-NFKB1 might constitute an opposite pathogenic pathway, reflecting the different balance between Th1 and Th17 in the two diseases.

A genome-wide association study identifies 2 susceptibility Loci for Crohn's disease in a Japanese population.

BACKGROUND & AIMS: Crohn's disease is an inflammatory bowel disease induced by multiple genetic and environmental factors. Genome-wide association studies have identified genetic factors that affect the risk for Crohn's disease in European populations, but information from other ethnic groups is scarce. We therefore investigated genetic factors associated with Crohn's disease in the Japanese population. METHODS: We performed a genome-wide association study with 372 individuals with Crohn's disease (cases) and 3389 controls, all from the Japanese population. To confirm identified associations, we performed a replication study with an independent panel of 1151 Crohn's disease cases and 15,800 controls. We also performed an association analysis using genome-wide genotype imputation in the discovery cohort. RESULTS: We confirmed associations of Crohn's disease with variants in MHC (rs7765379, P = 2.11 × 10(-59)), TNFSF15 (rs6478106, P = 3.87 × 10(-45)), and STAT3 (rs9891119, P = 2.24 × 10(-14)). We identified 2 new susceptibility loci: on chromosome 4p14 (rs1487630, P = 2.40 × 10(-11); odds ratio, 1.33), and in the SLC25A15-ELF1-WBP4 region on 13q14 (rs7329174 in ELF1, P = 5.12 × 10(-9); odds ratio, 1.27). CONCLUSIONS: In a genome-wide association study, we identified 2 new susceptibility loci for Crohn's disease in a Japanese population. These findings could increase our understanding of the pathogenesis of Crohn's disease.

Daikenchuto, a traditional Japanese herbal medicine, for the maintenance of surgically induced remission in patients with Crohn's disease: a retrospective analysis of 258 patients.

PURPOSE: Despite numerous studies, the best postoperative therapy for Crohn's disease is still undefined. We retrospectively evaluated the effects of postoperative maintenance therapy with daikenchuto, a traditional Japanese Kampo medicine, on the reoperation rate at 3 years in patients with Crohn's disease. METHODS: A total of 258 patients who underwent surgery for Crohn's disease were identified for the study. For the prevention of postoperative recurrence, patients were stratified to receive 5-aminosalicylic acid, azathioprine or daikenchuto, and their effects on preventing reoperation at 3 years were evaluated. RESULTS: Of the 258 patients, 44 required reoperation with intestinal resection within 3 years due to disease recurrence. The 3-year reoperation rate was significantly lower in the postoperative daikenchuto group than in the non-daikenchuto group (11.3 vs. 24.5 %, P = 0.01), and was similarly significantly lower in the postoperative 5-aminosalicylic acid group than in the non-5-aminosalicylic acid group (14.8 vs. 29.6 %, P = 0.0049). A multivariate Cox analysis showed that postoperative daikenchuto (P = 0.035) and postoperative 5-aminosalicylic acid (P = 0.022) were significantly and independently associated with the rate of reoperation at 3 years in patients with Crohn's disease. CONCLUSION: We propose that continuous daikenchuto therapy is a clinically useful and feasible maintenance therapy for the prevention of postoperative reoperation in patients with Crohn's disease.

Clinical outcomes of patients with remitting ulcerative colitis after discontinuation of indigo naturalis.

Indigo naturalis is an effective treatment for ulcerative colitis. However, long-term use of indigo naturalis causes adverse events, such as pulmonary hypertension. The natural history of patients with ulcerative colitis who discontinued indigo naturalis after induction therapy is unknown. Moreover, the clinical features of patients who relapsed within 52 weeks after the discontinuation of indigo naturalis are unclear. This study aimed to assess the clinical outcomes of patients with ulcerative colitis after discontinuation of indigo naturalis and to identify potential markers responsible for relapse. This single-center retrospective study investigated the follow-up of 72 patients who achieved a clinical response 8 weeks after indigo naturalis treatment. We observed relapse in patients with ulcerative colitis after the discontinuation of indigo naturalis. We analyzed the factors predicting long-term outcomes after discontinuation of indigo naturalis. Relapse was observed in 24%, 57%, and 71% of patients at 8, 26, and 52 weeks, respectively. There were no predictive markers in patients who relapsed within 52 weeks after the discontinuation of indigo naturalis. The ulcerative colitis relapse rate after indigo naturalis discontinuation was high. Follow-up treatment is required after the discontinuation of indigo naturalis in patients with ulcerative colitis.

Risk of venous thromboembolism with a central venous catheter in hospitalized Japanese patients with inflammatory bowel disease: a propensity score-matched cohort study.

BACKGROUND/AIMS: Thromboprophylaxis is recommended for hospitalized patients with inflammatory bowel disease (IBD) in Western countries, although it is selectively administered to high-risk patients in East Asia. A central venous catheter (CVC) is commonly placed in patients with IBD. Although CVC placement is considered a risk factor for venous thromboembolism (VTE), the degree of increased risk in patients with IBD is uncertain. This study aimed to identify the risk of VTE with CVC placement in hospitalized Japanese patients with IBD without thromboprophylaxis. METHODS: This retrospective cohort study included patients with ulcerative colitis or Crohn's disease who were admitted for disease flares at Keio University Hospital between January 2016 and December 2020. Patients who already had thrombosis or were administered any antithrombotic treatment on admission were excluded. VTE development during the hospitalization was surveyed, and VTE risk associated with CVC indwelling was estimated using propensity score matching and inverse probability of treatment weighting analyses. RESULTS: Altogether, 497 hospitalized patients with IBD (ulcerative colitis, 327; Crohn's disease, 170) were enrolled. VTE developed in 9.30% (12/129) of catheterized patients and in 0.82% (3/368) of non-catheterized patients. The propensity score matching yielded 127 matched pairs of patients. The catheterized group demonstrated higher odds for VTE than the non-catheterized group (odds ratio, 13.15; 95% confidence interval, 1.68-102.70). A similar result was obtained in the inverse probability of treatment weighting analysis (odds ratio, 11.02; 95% confidence interval, 2.64-46.10). CONCLUSIONS: CVC placement is a major risk factor for VTE among hospitalized Japanese patients with IBD without thromboprophylaxis.

Rationally-defined microbial consortia suppress multidrug-resistant proinflammatory Enterobacteriaceae via ecological control.

Persistent colonization and outgrowth of pathogenic organisms in the intestine may occur due to long-term antibiotic usage or inflammatory conditions, which perpetuate dysregulated immunity and tissue damage1,2. Gram-negative Enterobacteriaceae gut pathobionts are particularly recalcitrant to conventional antibiotic treatment3,4, though an emerging body of evidence suggests that manipulation of the commensal microbiota may be a practical alternative therapeutic strategy5-7. In this study, we rationally isolated and down-selected commensal bacterial consortia from healthy human stool samples capable of strongly and specifically suppressing intestinal Enterobacteriaceae. One of the elaborated consortia, consisting of 18 commensal strains, effectively controlled ecological niches by regulating gluconate availability, thereby reestablishing colonization resistance and alleviating antibiotic-resistant Klebsiella-driven intestinal inflammation in mice. Harnessing these microbial activities in the form of live bacterial therapeutics may represent a promising solution to combat the growing threat of proinflammatory, antimicrobial-resistant bacterial infection.

Video capsule endoscopy in inflammatory bowel disease.

Since its introduction into clinical practice in 2000, capsule endoscopy (CE) has become an important procedure for many pathologies of small bowel (SB) diseases, including inflammatory bowel disease (IBD). Currently, the most commonly used capsule procedures are small bowel capsule endoscopy (SBCE), colon CE (CCE), and the recently developed pan-enteric CE that evaluates the SB and colon in patients with Crohn's disease (CD). SBCE has a higher diagnostic performance compared to other radiological and conventional endoscopic modalities in patients with suspected CD. Additionally, CE plays an important role in monitoring the activity of CD in SB. It can also be used in evaluating response to anti-inflammatory treatment and detecting recurrence in postsurgical patients with CD who underwent bowel resection. Due to its increasing use, different scoring systems have been developed specifically for IBD. The main target with CCE is ulcerative colitis (UC). The second-generation colon capsule has shown high performance for the assessment of inflammation in patients with UC. CCE allows noninvasive evaluation of mucosal inflammation with a reduced volume of preparation for patients with UC.

Efficacy of Calcineurin Inhibitors for Induction of Remission in Intestinal Behçet's Disease.

Background: The efficacy of calcineurin inhibitors (CNIs) for induction of remission in intestinal Behçet's disease (intestinal BD) has not been explored. Methods: A multicenter retrospective case series study of patients with active intestinal BD treated with CNIs (cyclosporin and tacrolimus) was conducted. Results: Of 16 patients, 12 (75%) showed a clinical response and 5 (31.3%) achieved clinical remission after 2 weeks of CNI treatment. Similar efficacy of CNIs was observed even in 7 patients refractory to antitumor necrosis factor-alpha therapies. Endoscopic improvement was observed in 11 of 12 patients. Conclusions: CNIs may be promising treatment options for refractory intestinal BD.

Effectiveness and Durability of Ustekinumab Therapy With or Without Immunomodulators for Ulcerative Colitis Patients in Japan.

Background and Aims: The effectiveness and durability of ustekinumab therapy with or without thiopurine immunomodulators (IMs) for ulcerative colitis (UC) in real-world Asian, Japanese patients have not yet been elucidated. Methods: To evaluate the additive effects of IMs on ustekinumab, a retrospective cohort study of UC patients receiving ustekinumab with or without thiopurine IMs, azathioprine or 6-mercaptopurine, was conducted from March 2020 to August 2021. The primary endpoint was clinical remission or response rate at week 8. The secondary endpoints were clinical remission or response rates at weeks 24 and 52, the durability of each treatment, and adverse events. Results: Of the 50 patients with UC treated with ustekinumab, 42 were enrolled. Sixteen patients were treated with a combination of ustekinumab and an IM. The clinical response rates of all patients at weeks 8, 24, and 52 were 53.7%, 63.3%, and 42.9%, respectively. There was no significant difference in the clinical responses or remission rates between the combination therapy and monotherapy groups at weeks 8, 24, and 52. (50.0% vs. 56.0%, P = .757; 70.0% vs. 60.0%, P = .702; and 42.9% vs. 42.9%, P = 1.00, respectively). A Kaplan-Meier analysis showed no difference in IM use on the durability of ustekinumab treatment (log-rank test; P = .955). Conclusions: The response rate for Japanese UC patients is similar to previous reports based on American and European UC patients. There was no significant difference between the ustekinumab monotherapy group and the ustekinumab and IM combination group in the real world.

Decoding the diversity of killer immunoglobulin-like receptors by deep sequencing and a high-resolution imputation method.

The killer cell immunoglobulin-like receptor (KIR) recognizes human leukocyte antigen (HLA) class I molecules and modulates the function of natural killer cells. Despite its role in immunity, the complex genomic structure has limited a deep understanding of the KIR genomic landscape. Here we conduct deep sequencing of 16 KIR genes in 1,173 individuals. We devise a bioinformatics pipeline incorporating copy number estimation and insertion or deletion (indel) calling for high-resolution KIR genotyping. We define 118 alleles in 13 genes and demonstrate a linkage disequilibrium structure within and across KIR centromeric and telomeric regions. We construct a KIR imputation reference panel (nreference = 689, imputation accuracy = 99.7%), apply it to biobank genotype (ntotal = 169,907), and perform phenome-wide association studies of 85 traits. We observe a dearth of genome-wide significant associations, even in immune traits implicated previously to be associated with KIR (the smallest p = 1.5 × 10-4). Our pipeline presents a broadly applicable framework to evaluate innate immunity in large-scale datasets.

Predictors of necessity for endoscopic balloon dilatation in patients with Crohn's disease-related small bowel stenosis.

BACKGROUND AND AIM: In patients with Crohn's disease (CD) and small bowel stenosis, endoscopic balloon dilation (EBD) is considered to be useful in improving stenotic symptoms and avoiding surgery. However, it carries risks such as bleeding and perforation. The aim of this study was to identify the indications for endoscopic intervention in patients with CD and small bowel stenosis. METHODS: From November 2007 to March 2020, 143 CD patients with small bowel stenosis were enrolled in this study. We identified the factors associated with not requiring endoscopic intervention during long-term follow-up of these patients. RESULTS: Forty of the 143 patients had abdominal symptoms of stenosis and had undergone EBD, whereas the remaining 103 were asymptomatic and had not undergone endoscopic intervention. During long-term follow-up, 95 of those 103 patients never required endoscopic or surgical intervention. Multivariate logistic regression analysis revealed that not consuming an elemental diet (OR 3.18, 95% CI 1.48-6.82; p < .01) and ileocecal valve (ICV) stenosis (OR 0.30, 95% CI 0.11-0.83; p = .02) were independently associated with not requiring EBD. The cumulative emergency hospitalisation-free rate also tended to be higher in patients not consuming an elemental diet or with ICV stenosis. CONCLUSIONS: Two factors, namely not consuming an elemental diet and ICV stenosis, predict a long-term intervention-free prognosis in CD patients with small bowel stenosis.Key messagesWhen an endoscopically impassable small bowel stenosis is found in a CD patient, long-term follow-up without endoscopic intervention may be possible if the patient is asymptomatic, is not using an elemental diet, and the stenosis is ICV.

TH1 cell-inducing Escherichia coli strain identified from the small intestinal mucosa of patients with Crohn's disease.

Dysbiotic microbiota contributes to the pathogenesis of Crohn's disease (CD) by regulating the immune system. Although pro-inflammatory microbes are probably enriched in the small intestinal (SI) mucosa, most studies have focused on fecal microbiota. This study aimed to examine jejunal and ileal mucosal specimens from patients with CD via double-balloon enteroscopy. Comparative microbiome analysis revealed that the microbiota composition of CD SI mucosa differs from that of non-CD controls, with an increased population of several families, including Enterobacteriaceae, Ruminococcaceae, and Bacteroidaceae. Upon anaerobic culturing of the CD SI mucosa, 80 bacterial strains were isolated, from which 9 strains representing 9 distinct species (Escherichia coli, Ruminococcus gnavus, Klebsiella pneumoniae, Erysipelatoclostridium ramosum, Bacteroides dorei, B. fragilis, B. uniformis, Parabacteroides distasonis, and Streptococcus pasteurianus) were selected on the basis of their significant association with CD. The colonization of germ-free (GF) mice with the 9 strains enhanced the accumulation of TH1 cells and, to a lesser extent, TH17 cells in the intestine, among which an E. coli strain displayed high potential to induce TH1 cells and intestinal inflammation in a strain-specific manner. The present results indicate that the CD SI mucosa harbors unique pro-inflammatory microbiota, including TH1 cell-inducing E. coli, which could be a potential therapeutic target.

[A case of HIV infection associated with ulcerative colitis].

We describe a 42-year-old-man with HIV infection who developed ulcerative colitis. Ulcerative colitis was diagnosed on the basis of clinical symptoms, and the findings of colonoscopy, pathology and culture. Although remission of ulcerative colitis was induced by PSL and SASP, HIV infection progressed. Treatment with highly active antiretroviral therapy (HAART) was started. HIV viral load decreased to less than 50copies/ml and CD4 counts increased to over 400/microl. After discontinuance of PSL and SASP, he is still in good condition. This is the first report of HIV infection associated with ulcerative colitis in Japan. A relationship between immune disorder in advanced HIV infection and inflammatory bowel disease was suggested. Ulcerative colitis might be an important complication in HIV infection.

Ectopic colonization of oral bacteria in the intestine drives TH1 cell induction and inflammation.

Intestinal colonization by bacteria of oral origin has been correlated with several negative health outcomes, including inflammatory bowel disease. However, a causal role of oral bacteria ectopically colonizing the intestine remains unclear. Using gnotobiotic techniques, we show that strains of Klebsiella spp. isolated from the salivary microbiota are strong inducers of T helper 1 (TH1) cells when they colonize in the gut. These Klebsiella strains are resistant to multiple antibiotics, tend to colonize when the intestinal microbiota is dysbiotic, and elicit a severe gut inflammation in the context of a genetically susceptible host. Our findings suggest that the oral cavity may serve as a reservoir for potential intestinal pathobionts that can exacerbate intestinal disease.

Genetic characteristics of inflammatory bowel disease in a Japanese population.

BACKGROUND: Crohn's disease (CD) and ulcerative colitis (UC) are two major forms of inflammatory bowel disease (IBD). Meta-analyses of genome-wide association studies (GWAS) have identified 163 susceptibility loci for IBD among European populations; however, there is limited information for IBD susceptibility in a Japanese population. METHODS: We performed a GWAS using imputed genotypes of 743 IBD patients (372 with CD and 371 with UC) and 3321 controls. Using 100 tag single-nucleotide polymorphisms (SNPs) (P < 5 × 10(-5)), a replication study was conducted with an independent set of 1310 IBD patients (949 with CD and 361 with UC) and 4163 controls. In addition, 163 SNPs identified by a European IBD GWAS were genotyped, and genetic backgrounds were compared between the Japanese and European populations. RESULTS: In the IBD GWAS, two East Asia-specific IBD susceptibility loci were identified in the Japanese population: ATG16L2-FCHSD2 and SLC25A15-ELF1-WBP4. Among 163 reported SNPs in European IBD patients, significant associations were confirmed in 18 (8 CD-specific, 4 UC-specific, and 6 IBD-shared). In Japanese CD patients, genes in the Th17-IL23 pathway showed stronger genetic effects, whereas the association of genes in the autophagy pathway was limited. The association of genes in the epithelial barrier and the Th17-IL23R pathways were similar in the Japanese and European UC populations. CONCLUSIONS: We confirmed two IBD susceptibility loci as common for CD and UC, and East Asian-specific. The genetic architecture in UC appeared to be similar between Europeans and East Asians, but may have some differences in CD.

Food antigen-induced immune responses in Crohn's disease patients and experimental colitis mice.

BACKGROUND: In Crohn's disease (CD), the involvement of food antigens in immune responses remains unclear. The objective of this study was to detect immune responses against food antigens in CD patients and examine the mechanism in a mouse model of colitis. METHODS: We enrolled 98 CD patients, 50 ulcerative colitis patients, and 52 healthy controls (HCs) to compare the levels of serum immunoglobulin (Ig)Gs against 88 foods. The presence of serum IgGs against foods was also examined in interleukin (IL)-10 knockout (KO) mice in which CD4(+) T cell activation by antigenic food protein was assessed. Mice transferred with IL-10 KO cells received diets with or without food antigens, and the development of colitis was evaluated. RESULTS: The prevalence of IgGs against various foods, especially vegetables, grains, and nuts, was significantly higher in CD patients than in HCs. Similarly, the prevalence of IgGs against food proteins was higher in IL-10 KO mice than in BALB/c mice. Beta-conglycinin, identified as an antigenic food proteins in IL-10 KO mice, induced CD4(+) T cell production of interferon-γ and IL-17 through dendritic cell antigen presentation. Elimination of the food antigens ameliorated the development of colitis in mice without altering the composition of their intestinal microbiota. CONCLUSIONS: In CD colitis mice, intestinal inflammation via CD4(+) T cell hyperactivation was induced by food antigens associated with high serum IgG levels and was ameliorated by the elimination of food antigens. This disrupted immunological tolerance to food antigen, which might act as an exacerbating factor, remains to be elucidated in CD patients.