Real-world NUDT15 genotyping and thiopurine treatment optimization in inflammatory bowel disease: a multicenter study

BACKGROUND

This study evaluated the effectiveness of NUDT15 codon 139 genotyping in optimizing thiopurine treatment for inflammatory bowel disease (IBD) in Japan, using real-world data, and aimed to establish genotype-based treatment strategies.

METHODS

A retrospective analysis of 4628 IBD patients who underwent NUDT15 codon 139 genotyping was conducted. This study assessed the purpose of the genotyping test and subsequent prescriptions following the obtained results. Outcomes were compared between the Genotyping group (thiopurine with genotyping test) and Non-genotyping group (thiopurine without genotyping test). Risk factors for adverse events (AEs) were analyzed by genotype and prior genotyping status.

RESULTS

Genotyping test for medical purposes showed no significant difference in thiopurine induction rates between Arg/Arg and Arg/Cys genotypes, but nine Arg/Cys patients opted out of thiopurine treatment. In the Genotyping group, Arg/Arg patients received higher initial doses than the Non-genotyping group, while Arg/Cys patients received lower ones (median 25 mg/day). Fewer AEs occurred in the Genotyping group because of their lower incidence in Arg/Cys cases. Starting with < 25 mg/day of AZA reduced AEs in Arg/Cys patients, while Arg/Arg patients had better retention rates when maintaining ≥ 75 mg AZA. Nausea and liver injury correlated with thiopurine formulation but not dosage. pH-dependent mesalamine reduced leukopenia risk in mesalamine users.

CONCLUSIONS

NUDT15 codon 139 genotyping effectively reduces thiopurine-induced AEs and improves treatment retention rates in IBD patients after genotype-based dose adjustments. This study provides data-driven treatment strategies based on genotype and identifies risk factors for specific AEs, contributing to a refined thiopurine treatment approach.

Duodenal microbiome in chronic kidney disease

BACKGROUND

The intestinal microbiome is involved in the pathogenesis of chronic kidney disease (CKD). Despite its importance, the microbiome of the small intestinal mucosa has been little studied due to sampling difficulties, and previous studies have mainly focused on fecal sources for microbiome studies. We aimed to characterize the small intestinal microbiome of CKD patients by studying the microbiome collected from duodenal and fecal samples of CKD patients and healthy controls.

METHODS

Overall, 28 stage 5 CKD patients and 21 healthy participants were enrolled. Mucosal samples were collected from the deep duodenum during esophagogastroduodenoscopy and fecal samples were also collected. The 16S ribosomal RNA gene sequencing using Qiime2 was used to investigate and compare the microbial structure and metagenomic function of the duodenal and fecal microbiomes.

RESULTS

The duodenal flora of CKD patients had decreased alpha diversity compared with the control group. On the basis of taxonomic composition, Veillonella and Prevotella were significantly reduced in the duodenal flora of CKD patients. The tyrosine and tryptophan metabolic pathways were enhanced in the urea toxin-related metabolic pathways based on the Kyoto Encyclopedia of Genes and Genomes database.

CONCLUSION

The small intestinal microbiome in CKD patients is significantly altered, indicating that increased intestinal permeability and production of uremic toxin may occur in the upper small intestine of CKD patients.

Small bowel capsule endoscopy examination and open access database with artificial intelligence: The SEE-artificial intelligence project

OBJECTIVES

Artificial intelligence (AI) may be practical for image classification of small bowel capsule endoscopy (CE). However, creating a functional AI model is challenging. We attempted to create a dataset and an object detection CE AI model to explore modeling problems to assist in reading small bowel CE.

METHODS

We extracted 18,481 images from 523 small bowel CE procedures performed at Kyushu University Hospital from September 2014 to June 2021. We annotated 12,320 images with 23,033 disease lesions, combined them with 6161 normal images as the dataset, and examined the characteristics. Based on the dataset, we created an object detection AI model using YOLO v5 and we tested validation.

RESULTS

We annotated the dataset with 12 types of annotations, and multiple annotation types were observed in the same image. We test validated our AI model with 1396 images, and sensitivity for all 12 types of annotations was about 91%, with 1375 true positives, 659 false positives, and 120 false negatives detected. The highest sensitivity for individual annotations was 97%, and the highest area under the receiver operating characteristic curve was 0.98, but the quality of detection varied depending on the specific annotation.

CONCLUSIONS

Object detection AI model in small bowel CE using YOLO v5 may provide effective and easy-to-understand reading assistance. In this SEE-AI project, we open our dataset, the weights of the AI model, and a demonstration to experience our AI. We look forward to further improving the AI model in the future.

Ustekinumab Decreases Circulating Th17 Cells in Ulcerative Colitis

Objective T helper (Th) cells play a central role in the pathogenesis of ulcerative colitis (UC). The present study analyzed the changes in circulating T cells by administration of ustekinumab (UST), an interleukin-12/23p40 antibody. Methods CD4 T cells were isolated from peripheral blood at 0 and 8 weeks after UST treatment, and we analyzed the proportion of CD4 T cells by flow cytometry. Clinical information and laboratory data were obtained at 0, 8, and 16 weeks. Patients We evaluated 13 patients with UC who received UST for the induction of remission between July 2020 and August 2021. Results The median partial Mayo score improved from 4 (1-7) to 0 (0-6) (p<0.001) with UST. Among serological parameters, albumin concentrations, C-reactive protein concentrations, the sedimentation rate, and leucine-rich alpha 2 glycoprotein concentrations showed significant improvement with UST. A flow cytometric analysis of circulating CD4 T cells showed that the percentage of Th17 cells was significantly decreased by UST treatment in all patients (1.85% to 0.98%, p<0.0001). Th1 cells were significantly increased by UST treatment (9.52% to 10.4%, p<0.05), but Th2 and regulatory T cells were not significantly different. The high-Th17 subgroup had a significantly better partial Mayo score than the low-Th17 subgroup at 16 weeks after UST treatment (0 vs. 1, p=0.028). Conclusion Treatment with UST decreases circulating Th17 cells, suggesting that this change may be related to the anti-inflammatory effect of UC.

White Blood Cell Counts and Future Relapse in Ulcerative Colitis under Low-Dose Thiopurine Treatment in Real-World Practice: A 3-Year Japanese Multi-Center Retrospective Cohort Study

Introduction

Whether white blood cell (WBC) counts are predictors for the effectiveness of thiopurine treatment in ulcerative colitis (UC) has been inconclusive in previous studies with small sample sizes. We investigated the association between WBC counts and future relapses in UC patients in a large-scale multi-center study.

Methods

This retrospective cohort study enrolled a total of 723 UC patients in remission from 33 hospitals and followed up for 3 years. Relapse was defined as a need for treatment intensification. The risk of relapse was compared among patients with the baseline WBC counts <3,000/µL (N = 31), 3,000-4,000/µL (N = 167), 4,000-5,000/µL (N = 241), and ≥5,000/µL (N = 284) using a Cox regression model analysis. Moreover, exploratory analyses were conducted to identify other factors predicting relapse.

Results

During a median follow-up period of 1,095 (interquartile range, 1,032-1,119) days, relapse occurred in 17.2% (125/723). In a crude analysis, WBC counts were not associated with relapse; hazard ratios (HRs) (95% confidence interval [CI]) were 1.50 (0.74-3.06), 1.02 (0.66-1.59), and 0.67 (0.43-1.05) in WBC <3,000/µL, 3,000-4,000/µL, and 4,000-5,000/µL groups, respectively (WBC ≥5,000/µL group, as reference). Multivariable-adjusted analyses showed similar results; HRs (95% CI) were 1.21 (0.59-2.49), 1.08 (0.69-1.69), and 0.69 (0.44-1.07), in <3,000/µL, 3,000-4,000/µL, and 4,000-5,000/µL groups, respectively. In the exploratory analyses, thiopurine use <1 year and a mean corpuscular volume <90 fL were predictors for relapse.

Discussion/Conclusion

WBC counts were not predictors for future relapses in patients with UC treated with thiopurine as a maintenance therapy.

Immunomodulators after the discontinuation of anti-tumor necrosis factor-alpha antibody treatment and relapse in ulcerative colitis: A multicenter cohort study

BACKGROUND AND AIM

Strategies to reduce relapse using immunomodulators (IMs) after discontinuing anti-tumor necrosis factor-alpha (TNF-α) antibody treatment are controversial in patients with ulcerative colitis (UC). In this study, we assessed the association between IMs after discontinuing anti-TNF-α antibody treatment and relapse in patients with UC.

METHODS

This retrospective, multicenter cohort study included 257 patients with UC in clinical remission. These patients discontinued anti-TNF-α antibody treatment between June 2010 and March 2019 and were followed up until March 2020. We evaluated the differences in relapse rates between patients with IMs (IM group) and those without IMs (non-IM group) after discontinuing the treatment. Relapse was defined as further undergoing an induction treatment or colectomy. Cox proportional hazards models adjusted for confounders were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for relapse. Exploratory analyses were performed to identify other factors that could predict relapse.

RESULTS

During the median follow-up period of 22 months (interquartile range: 10-41), 114 relapses occurred: 42/100 (42.0%) in the IM group and 72/157 (45.9%) in the non-IM group. In the multivariable analysis, IMs were not associated with relapse (HR, 0.95 [95% CI, 0.64-1.41]). In the exploratory analyses, discontinuation due to side effects (HR, 1.83 [95% CI, 1.18-2.82]) and younger age (HR, 0.99 [95% CI, 0.98-1.00]) predicted relapse.

CONCLUSION

Immunomodulators were not associated with relapse after discontinuing anti-TNF-α antibody treatment in patients with UC. Careful patient follow-up is needed when discontinuing due to side effects or when the patient is of a younger age at the time of discontinuation.

Disease Flares Following COVID-19 Vaccination in Patients with Inflammatory Bowel Disease

Objective Flares of inflammatory bowel disease (IBD) can occur infrequently after vaccination for coronavirus disease 2019 (COVID-19), although the details of this phenomenon are poorly understood. To clarify the possibility of an unfavorable response in patients with IBD, we investigated IBD-related symptoms during the COVID-19 vaccination. Methods Between October 2021 and February 2022, we obtained the COVID-19 vaccination status of 411 IBD patients who were being treated at our institution. The disease course of IBD after vaccination was investigated in 188 patients with ulcerative colitis (UC) and 119 patients with Crohn's disease (CD) who had received at least one dose of the vaccine during the clinical remission phase. The baseline characteristics before vaccination were compared between the patients with UC with or without disease flares. Results During the 30-day follow-up period, eight patients with UC (4.3%) and one patient with CD (0.8%) experienced disease flares following vaccination. Disease flares occurred after the first vaccination in six patients and after the second vaccination in three patients. As for the timing of onset of disease flares, eight events (88.9%) occurred within one week of vaccination. Two patients required hospitalization, and one patient with CD required surgery for an intra-abdominal abscess. The baseline characteristics did not significantly differ between patients with UC who experienced flares and those who did not. Conclusion IBD flares following COVID-19 vaccination are rare and vaccination should therefore be recommended for patients with IBD. However, the possibility of disease flares should be considered for approximately one week after each vaccination, especially in patients with UC.

Clinical Features of Gastroduodenal Ulcers in Kidney Transplant Patients

Objective The risk of developing peptic ulcers and gastrointestinal bleeding is high in patients with chronic kidney disease (CKD). Whether or not kidney transplant patients, who are treated with multiple medications, including immunosuppressive drugs, are at an increased risk of developing peptic ulcers is unclear. Methods In this retrospective study, we compared the clinical and endoscopic features of gastroduodenal ulcers between kidney transplant patients and CKD patients. The subjects underwent upper gastrointestinal endoscopy between January 2015 and March 2021. Results Gastroduodenal ulcers were observed more frequently (6.5%) in kidney transplant patients than in CKD patients (2.1%) (p=0.026). Due in part to the lower median age in the kidney transplant ulcer group than in the CKD ulcer group (59 vs. 70 years old, p=0.016), the rates of atrophic gastritis and Helicobacter pylori infection were also lower in the kidney transplant ulcer group than in the CKD ulcer group. Significantly more kidney transplant patients were treated with acid secretion inhibitors than CKD ulcer patients (100% vs. 34.8%, p=0.0005). Peptic ulcers were observed frequently in kidney transplant patients, even though common risk factors for gastroduodenal ulcers other than immunosuppressive drugs were few. All kidney transplant patients were taking immunosuppressive medications, and tacrolimus, mycophenolate mofetil, and methylprednisolone were taken more frequently than others. Conclusion Kidney transplant patients have a high risk of developing gastroduodenal ulcers. All kidney transplant patients take immunosuppressive medications, so there may be an association between immunosuppressive medications and gastroduodenal ulcer development.

Trajectory analyses to identify persistently low responders to COVID-19 vaccination in patients with inflammatory bowel disease: a prospective multicentre controlled study, J-COMBAT

BACKGROUND

The degree of immune response to COVID-19 vaccination in inflammatory bowel disease (IBD) patients based on actual changes in anti-SARS-CoV-2 antibody titres over time is unknown.

METHODS

Data were prospectively acquired at four predetermined time points before and after two vaccine doses in a multicentre observational controlled study. The primary outcome was humoral immune response and vaccination safety in IBD patients. We performed trajectory analysis to identify the degree of immune response and associated factors in IBD patients compared with controls.

RESULTS

Overall, 645 IBD patients and 199 control participants were analysed. At 3 months after the second vaccination, the seronegative proportions were 20.3% (combination of anti-tumour necrosis factor [TNF]α and thiopurine) and 70.0% (triple combination including steroids), despite that 80.0% receiving the triple combination therapy were seropositive at 4 weeks after the second vaccination. Trajectory analyses indicated three degrees of change in immune response over time in IBD patients: high (57.7%), medium (35.6%), and persistently low (6.7%). In the control group, there was only one degree, which corresponded with IBD high responders. Older age, combined anti-TNFα and thiopurine (odds ratio [OR], 37.68; 95% confidence interval [CI], 5.64-251.54), steroids (OR, 21.47; 95%CI, 5.47-84.26), and tofacitinib (OR, 10.66; 95%CI, 1.49-76.31) were factors associated with persistently low response. Allergy history (OR, 0.17; 95%CI, 0.04-0.68) was a negatively associated factor. Adverse reactions after the second vaccination were significantly fewer in IBD than controls (31.0% vs 59.8%; p < 0.001).

CONCLUSIONS

Most IBD patients showed a sufficient immune response to COVID-19 vaccination regardless of clinical factors. Assessment of changes over time is essential to optimize COVID-19 vaccination, especially in persistently low responders.

Usefulness of Serum Leucine-Rich Alpha-2 Glycoprotein as a Surrogate Marker of Small Bowel Mucosal Injury in Crohn's Disease

Introduction

Although the importance of mucosal healing has been suggested in Crohn's disease, it is difficult to repeat endoscopy, especially for the entire small bowel. Recently, serum leucine-rich alpha-2 glycoprotein (LRG) has been used as a surrogate marker of endoscopy. However, few studies have investigated a correlation between LRG and mucosal injury of the entire small bowel.

Methods

We retrospectively analyzed the clinical data of 30 patients with Crohn's disease from June 2020 to August 2022 at Yamaguchi Red Cross Hospital. All the patients were surveyed through the gastrointestinal tract by esophagogastroduodenoscopy, total colonoscopy, and capsule endoscopy (CE). Subjects with mucosal injury only in the small bowel were selected. Then, we assessed the relationship between serum biomarkers (LRG, C-reactive protein [CRP], hemoglobin, albumin) and small bowel mucosal injury scores (Lewis score [LS], Capsule Endoscopy Crohn's Disease Activity Index [CECDAI], and Crohn's Disease Activity in Capsule Endoscopy [CDACE]) calculated by CE.

Results

LRG and CRP were significantly correlated with small bowel mucosal injury scores (LS, CECDAI, CDACE) (p < 0.05, Spearman's rank correlation coefficient). The degree of correlation was greater for LRG than for CRP.

Conclusions

LRG is a useful surrogate marker that closely reflects small bowel mucosal injury in the entire small bowel.

Ferroptosis in the colon epithelial cells as a therapeutic target for ulcerative colitis

BACKGROUND

Ferroptosis, a type of programmed cell death triggered by oxidative stress, was suspected to play a role in ulcerative colitis. Indigo naturalis is highly effective against ulcerative colitis, but its mechanism is unclear. This study found that indigo naturalis treatment suppressed ferroptosis.

METHODS

We analyzed 770 mRNA expressions of patients with ulcerative colitis. Suppression of ferroptosis by indigo naturalis treatment was shown using a cell death assay. Malondialdehyde levels and reactive oxygen species were analyzed in CaCo-2 cells treated with indigo naturalis. Glutathione metabolism was shown by metabolomic analysis. Extraction of the ingredients indigo naturalis from the rectal mucosa was performed using liquid chromatograph-mass spectrometry.

RESULTS

Gene expression profiling showed that indigo naturalis treatment increased antioxidant genes in the mucosa of patients with ulcerative colitis. In vitro analysis showed that nuclear factor erythroid-2-related factor 2-related antioxidant gene expression was upregulated by indigo naturalis. Indigo naturalis treatment rendered cells resistant to ferroptosis. Metabolomic analysis suggested that an increase in reduced glutathione by indigo naturalis. The protein expression of CYP1A1 and GPX4 was increased in the rectum by treatment with indigo naturalis. The main ingredients of indigo naturalis, indirubin and indigo inhibited ferroptosis. Indirubin was detected in the rectal mucosa of patients with ulcerative colitis who were treated with indigo naturalis.

CONCLUSIONS

Suppression of ferroptosis by indigo naturalis in the intestinal epithelium could be therapeutic target for ulcerative colitis. The main active ingredient of indigo naturalis may be indirubin.

Genetic architecture of the inflammatory bowel diseases across East Asian and European ancestries

Inflammatory bowel diseases (IBDs) are chronic disorders of the gastrointestinal tract with the following two subtypes: Crohn's disease (CD) and ulcerative colitis (UC). To date, most IBD genetic associations were derived from individuals of European (EUR) ancestries. Here we report the largest IBD study of individuals of East Asian (EAS) ancestries, including 14,393 cases and 15,456 controls. We found 80 IBD loci in EAS alone and 320 when meta-analyzed with ~370,000 EUR individuals (~30,000 cases), among which 81 are new. EAS-enriched coding variants implicate many new IBD genes, including ADAP1 and GIT2. Although IBD genetic effects are generally consistent across ancestries, genetics underlying CD appears more ancestry dependent than UC, driven by allele frequency (NOD2) and effect (TNFSF15). We extended the IBD polygenic risk score (PRS) by incorporating both ancestries, greatly improving its accuracy and highlighting the importance of diversity for the equitable deployment of PRS.

Predictive factors of the clinical efficacy of ustekinumab in patients with refractory Crohn's disease: tertiary centers experience in Japan

PURPOSE

Therapeutic efficacy of ustekinumab in the real-world data is limited in patients with refractory Crohn's disease (CD). In addition, factors predictive of better therapeutic efficacy of ustekinumab remains unsolved in CD. We aimed to evaluate therapeutic efficacy of ustekinumab in patients with refractory CD and to identify the factors associated with the efficacy of ustekinumab.

METHODS

We retrospectively analyzed the clinical data of 72 patients treated with ustekinumab for refractory CD. Therapeutic efficacy was assessed at weeks 8, 26, 52, and 104 on the basis of dual remission, defined as the combination of Crohn's Disease Activity Index < 150 and CRP < 0.3 mg/dL, and factors predictive of the induction and maintenance of dual remission were investigated. The cumulative continuation rates and safety of ustekinumab were assessed.

RESULTS

The dual remission rates at weeks 8, 26, 52, and 104 were 31.9%, 37.9%, 47.5%, and 42.6%, respectively. A short disease duration (≤ 2 years) and higher baseline serum albumin levels (≥ 3.1 g/dL) were positively associated with dual remission at weeks 8 and 52. Meanwhile, higher serum CRP levels (≥ 1.19 mg/dL) were negatively associated with dual remission at week 8. The cumulative ustekinumab continuation rate was favorable, and no severe adverse events were found.

CONCLUSION

A short disease duration and higher baseline serum albumin levels might be predictive of favorable therapeutic efficacy of ustekinumab in refractory CD. Induction efficacy appears to be lower in patients with higher serum CRP levels.

Continuous use of antithrombotic medications during peri-endoscopic submucosal dissection period for colorectal lesions: A propensity score matched study

BACKGROUND AND AIM

The aim of this study was to elucidate the continuous use of antithrombotic medications during the peri-colorectal endoscopic submucosal dissection (ESD) period.

METHODS

This study included 468 patients with colorectal epithelial neoplasms treated by ESD, consisting of 82 under antithrombotic medications and 386 patients without the medications. Among patients taking antithrombotic medications, antithrombotic agents were continued during the peri-ESD period. Clinical characteristics and adverse events were compared after propensity score matching.

RESULTS

Before and after propensity score matching, post-colorectal ESD bleeding rate was higher in patients continuing antithrombotic medications (19.5% and 21.6%, respectively) than in those not taking antithrombotic medications (2.9% and 5.4%, respectively). In the Cox regression analysis, continuation of antithrombotic medications was associated with post-ESD bleeding risk (hazard ratio, 3.73; 95% confidence interval, 1.2-11.6; P < 0.05) compared with patients without antithrombotic therapy. All patients who experienced post-ESD bleeding were successfully treated by endoscopic hemostasis procedure or conservative therapy.

CONCLUSIONS

Continuation of antithrombotic medications during the peri-colorectal ESD period increases the risk of bleeding. However, the continuation may be acceptable under careful monitoring for post-ESD bleeding.

Clinical Guidelines for Diagnosis and Management of Juvenile Polyposis Syndrome in Children and Adults-Secondary Publication

Juvenile polyposis syndrome (JPS) is a rare disease characterized by multiple hamartomatous polyps within the gastrointestinal tract. SMAD4 or BMPR1A is known as a causative gene of JPS. Approximately 75% of newly diagnosed cases have an autosomal-dominantly inherited condition, whereas 25% are sporadic without previous history of polyposis in the family pedigree. Some patients with JPS develop gastrointestinal lesions in childhood and require continuous medical care until adulthood. JPS is classified into three categories according to phenotypic features of polyp distributions, including generalized juvenile polyposis, juvenile polyposis coli, and juvenile polyposis of the stomach. Juvenile polyposis of the stomach is caused by germline pathogenic variants of SMAD4 with a high risk leading to gastric cancer. Pathogenic variants of SMAD4 are also associated with hereditary hemorrhagic telangiectasia-JPS complex, inducing regular cardiovascular survey. Despite growing concerns regarding the managing JPS in Japan, there are no practical guidelines. To address this situation, the guideline committee was organized by the Research Group on Rare and Intractable Diseases granted by the Ministry of Health, Labor and Welfare involving specialists from multiple academic societies. The present clinical guidelines explain the principles in the diagnosis and management of JPS with three clinical questions and corresponding recommendations based on a careful review of the evidence and involve incorporating the concept of the Grading of Recommendations, Assessment, Development, and Evaluation system. Herein, we present the clinical practice guidelines of JPS to promote seamless implementation of accurate diagnosis and appropriate management of pediatric, adolescent, and adult patients with JPS.

The Compositional Structure of the Small Intestinal Microbial Community via Balloon-Assisted Enteroscopy

INTRODUCTION

An association has been found between human-gut microbiota and various diseases (e.g., metabolic disease) by analyzing fecal or colonic microbiota. Despite the importance of the small intestinal microbiota, sampling difficulties prevent its full analysis. We investigated the composition and metagenomic functions of microbiota along the small intestine and compared them with the microbiota from feces and from other gastrointestinal (GI) sites.

METHODS

Mucosal samples from the six GI sites (stomach, duodenum, distal jejunum, proximal ileum, terminal ileum, and rectum) were collected under balloon-assisted enteroscopy. Fecal samples were collected from all participants. The microbial structures and metagenomic functions of the small intestinal mucosal microbiota were compared with those from feces and other GI sites using 16S ribosomal RNA gene sequencing.

RESULTS

We analyzed 133 samples from 29 participants. Microbial beta diversity analysis showed that the jejunum and ileum differed significantly from the lower GI tract and the feces (p < 0.001). Jejunal and duodenal microbiotas formed similar clusters. Wide clusters spanning the upper and lower GI tracts were observed with the ileal microbiota, which differed significantly from the jejunal microbiota (p < 0.001). Veillonella and Streptococcus were abundant in the jejunum but less so in the lower GI tract and feces. The metagenomic functions associated with nutrient metabolism differed significantly between the small intestine and the feces.

CONCLUSIONS

The fact that the compositional structures of small intestinal microbiota differed from those of fecal and other GI microbiotas reveals that analyzing the small intestinal microbiota is necessary for association studies on metabolic diseases and gut microbiota.

Crohn's Disease and Early Exposure to Thiopurines are Independent Risk Factors for Mosaic Chromosomal Alterations in Patients with Inflammatory Bowel Diseases

BACKGROUND AND AIMS

Mosaic chromosomal alterations [mCAs] increase the risk for haematopoietic malignancies and may be risk factors for several other diseases. Inflammatory bowel diseases [IBDs], including Crohn's disease [CD] and ulcerative colitis [UC], are associated with mCAs, and patients may be at risk for haematopoietic malignancy development and/or modification of IBD phenotypes. In the present study, we screened patients with IBD for the presence of mCAs and explored the possible pathophysiological and genetic risk factors for mCAs.

METHODS

We analysed mCAs in peripheral blood from 3339 patients with IBD and investigated the clinical and genetic risk factors for mCAs.

RESULTS

CD and exposure to thiopurines before the age of 20 years were identified as novel independent risk factors for mCAs [odds ratio = 2.15 and 5.68, p = 1.17e-2 and 1.60e-3, respectively]. In contrast, there were no significant associations of disease duration, anti-tumour necrosis factor alpha antibodies, or other clinical factors with mCAs. Gene ontology enrichment analysis revealed that genes specifically located in the mCAs in patients with CD were significantly associated with factors related to mucosal immune responses. A genome-wide association study revealed that ERBIN, CD96, and AC068672.2 were significantly associated with mCAs in patients with CD [p = 1.56e-8, 1.65e-8, and 4.92e-8, respectively].

CONCLUSIONS

The difference in mCAs between patients with CD and UC supports the higher incidence of haematopoietic malignancies in CD. Caution should be exercised when using thiopurines in young patients with IBD, particularly CD, in light of possible chromosomal alterations.

One-year clinical efficacy and safety of indigo naturalis for active ulcerative colitis: a real-world prospective study

BACKGROUND/AIMS

Recent studies suggested a favorable effect of indigo naturalis (IN) in inducing remission for refractory ulcerative colitis (UC), however, the maintenance effect of IN for patients with UC remains unknown. Therefore, we conducted a prospective uncontrolled open-label study to analyze the efficacy and safety of IN for patients with UC.

METHODS

Patients with moderate to severe active UC (clinical activity index [CAI] ≥ 8) took 2 g/day of IN for 52 weeks. CAI at weeks 0, 4, 8, and 52 and Mayo endoscopic subscore (MES) and Geboes score (GS) at weeks 0, 4, and 52 were assessed. Clinical remission (CAI ≤ 4), mucosal healing (MES ≤ 1), and histological healing (GS ≤ 1) rates at each assessment were evaluated. Overall adverse events (AEs) during study period were also evaluated. The impact of IN on mucosal microbial composition was assessed using 16S ribosomal RNA gene sequences.

RESULTS

Thirty-three patients were enrolled. The rates of clinical remission at weeks 4, 8, and 52 were 67%, 76%, and 73%, respectively. The rates of mucosal healing at weeks 4 and 52 were 48% and 70%, respectively. AEs occurred in 17 patients (51.5%) during follow-up. Four patients (12.1%) showed severe AEs, among whom 3 manifested acute colitis. No significant alteration in the mucosal microbial composition was observed with IN treatment.

CONCLUSIONS

One-year treatment of moderate to severe UC with IN was effective. IN might be a promising therapeutic option for maintaining remission in UC, although the relatively high rate of AEs should be considered.

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 (n_reference = 689, imputation accuracy = 99.7%), apply it to biobank genotype (n_total = 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.

[A case of chronic enteropathy associated with SLCO2A1 gene diagnosed by capsule endoscopy and successfully treated by ferric carboxymaltose]

Chronic non-specific multiple ulcers of the small intestine is a disease condition postulated in Japan. It is an uncommon gastrointestinal disease that causes chronic anemia and hypoalbuminemia by causing numerous ulcers without any histopathologically identifiable features. In recent years, it has been revealed that the mutations of SLCO2A1, which codes the prostaglandin transporter protein, are the cause of this disease;it is called the new name "chronic enteropathy associated with SLCO2A1 gene." The ileum, except the terminal ileum, is the most common place making it difficult to identify major lesions. Other than conservative treatments, such as nutrition therapy and iron supplements, no effective treatment has been identified so far. We present a case of chronic non-specific multiple ulcers of the small intestine diagnosed by capsule endoscopy and effectively treated by ferric carboxymaltose. A 48-year-old female had chronic iron deficiency anemia since around the age of 15. Because of severe anemia, the patient had upper and lower endoscopy at the age of 47 to find the source of the bleeding, but it was not detected. Except for the terminal ileum, the capsule endoscopy revealed ring-like ulcers, tape-like ulcers, and oblique ulcer scars in the ileum. Genetic analysis showed a homozygous mutation in intron 7, c.940+1G>A, indicating a definitive diagnosis of non-specific multiple ulcers of the small intestine. Anemia and anemia-related symptoms such as general malaise persisted despite continuous oral administration of iron drugs. Three intravenous injections of ferric carboxymaltose increased hemoglobin and enhanced the symptoms.

Role of barium enema examination for the diagnosis of submucosal invasion depth in T1 colorectal cancers

BACKGROUND

The indication for endoscopic resection for submucosally invasive colorectal cancer (T1-CRC) depends on the preoperative diagnosis of invasion depth. The aim of this investigation was to evaluate the association between barium enema examination (BE) profile views and depth of submucosal (SM) invasion in CRCs.

METHODS

We reviewed the radiographic and endoscopic findings of 145 T1-CRCs diagnosed from 2008 to 2019. We measured the widths of horizontal and vertical rigidity under a BE profile view corresponding to CRC and compared the values with SM invasion depth. Horizontal rigidity was defined as the horizontal length and vertical rigidity as the vertical width of the barium defect corresponding to each target lesion. The most appropriate cut-off values for predicting SM invasion ≥1.8 mm were calculated by receiver operating characteristic curve analysis.

RESULTS

Values of horizontal rigidity (r = 0.626, P < 0.05) and vertical rigidity (r = 0.482, P < 0.05) correlated significantly with SM invasion depth. The most appropriate cut-off values for the prediction of SM invasion depth ≥ 1.8 mm were 4.5 mm for horizontal rigidity, with an accuracy of 80.7%; and 0.7 mm for vertical rigidity, with an accuracy of 77.9%. The prevalence of lympho-vascular invasion was significantly different when those cut-off values were applied (43.2% vs. 17.5% for horizontal rigidity, P < 0.005).

CONCLUSIONS

In T1-CRC, values of horizontal and vertical rigidities under a BE profile view were correlated with SM invasion depth. While the accuracy of the rigidities for the prediction of SM invasion depth ≥ 1.8 mm was not high, horizontal rigidity may be predictive of lympho-vascular invasion, thus aiding in therapeutic decision-making.

Risk of Rebleeding in Patients with Small Bowel Vascular Lesions

Objective With recent advances in endoscopic modalities, small bowel vascular lesions (SBVLs) are often now detected in patients with gastrointestinal bleeding. Given the high invasiveness of endoscopic treatment, it is important to select patients at high risk for bleeding. To assess the risk of rebleeding in patients with SBVLs as a systemic disease rather than a gastrointestinal disease in relation to their general health. Methods We retrospectively analyzed the clinical data of 55 patients with SBVLs among patients with obscure gastrointestinal bleeding. The possible association between the clinical findings and the updated Charlson comorbidity index with rebleeding was evaluated. Results Gastrointestinal rebleeding occurred in 20 patients (36.4%) during the follow-up period. The presence of multiple comorbidities as indicated by an updated Charlson comorbidity index of ≥4 was a risk factor for rebleeding (hazard ratio, 3.64; p=0.004). Other risk factors were arteriosclerosis of the superior mesenteric artery and multiple SBVLs. Endoscopic hemostasis and the discontinuation of antithrombotic medications were not significantly associated with rebleeding. Patients with a high updated Charlson comorbidity index had a high risk of death of causes other than gastrointestinal rebleeding. Conclusion Gastrointestinal rebleeding is not a rare condition among patients with SBVLs. Patients with poor general health may therefore have a higher risk of rebleeding.

Ustekinumab Improves Active Crohn's Disease by Suppressing the T Helper 17 Pathway

BACKGROUND

Ustekinumab (UST), an antibody targeting the p40 subunit of interleukin (IL)-12 and IL-23, is effective in treating Crohn's disease (CD). To clarify the mechanism of UST, we investigated T-cell differentiation in CD patients treated with UST.

METHODS

Twenty-seven patients with active CD were enrolled in this study. Seventeen patients were treated with UST, and 10 patients were treated with anti-tumor necrosis factor (TNF)-alpha therapy. The changes in the proportions of T-cell subsets after these therapies were analyzed by flow cytometry. Comprehensive gene expression changes in the colonic mucosa were also evaluated.

RESULTS

The frequency of T helper (Th) 17 cells was significantly decreased in the peripheral blood of patients with active CD after UST therapy. Anti-TNF therapy had a minimal effect on Th17 cells but increased the proportion of regulatory T cells. Enrichment analysis showed the expression of genes involved in the Th17 differentiation pathway was downregulated in the colonic mucosa after UST but not anti-TNF therapy. There were no common differentially expressed genes between CD patients treated with UST and anti-TNF therapy, suggesting a clear difference in their mechanism of action.

CONCLUSION

In patients with active CD, UST therapy suppressed Th17 cell differentiation both in the peripheral blood and colonic tissues.

Gastric microbiota in patients with Helicobacter pylori-negative gastric MALT lymphoma

To investigate the mucosal microbiota in the stomach of patients with Helicobacter pylori-negative mucosa-associated lymphoid tissue (MALT) lymphoma by means of metagenomic analysis.Although some gastric MALT lymphomas are associated with the presence of H. pylori, other gastric MALT lymphomas occur independently of H. pylori infection. The pathogenesis of H. pylori-negative MALT lymphoma remains unclear.Mucosal biopsy specimens were collected from the gastric body from 33 MALT lymphoma patients with gastric lesions, including both H. pylori-infection naïve patients and posteradication patients, as well as 27 control participants without H. pylori infection or cancer. Subsequently, the samples were subjected to 16S rRNA gene sequencing. Quantitative insights into microbial ecology, linear discriminant analysis effect size, and phylogenetic investigation of communities by reconstruction of unobserved states softwares were used to analyze the participants' microbiota.H. pylori-negative MALT lymphoma patients had significantly lower alpha diversity (P = .04), compared with control participants. Significant differences were evident in the microbial composition (P = .04), as determined by comparison of beta diversity between the 2 groups. Taxonomic composition analysis indicated that the genera Burkholderia and Sphingomonas were significantly more abundant in MALT lymphoma patients, while the genera Prevotella and Veillonella were less abundant. Functional microbiota prediction showed that the predicted gene pathways "replication and repair," "translation," and "nucleotide metabolism" were downregulated in MALT lymphoma patients.H. pylori-negative MALT lymphoma patients exhibited altered gastric mucosal microbial compositions, suggesting that altered microbiota might be involved in the pathogenesis of H. pylori-negative MALT lymphoma.

Adding Thiopurine After Loss of Response to Infliximab Versus Early Combination in Treating Crohn's Disease: A Retrospective Study

BACKGROUND

Although combining thiopurine with infliximab (IFX) is considered to improve the clinical efficacy of IFX when treating Crohn's disease (CD), it also increases the risk of adverse events (AEs). We compared the efficacy and safety of delayed thiopurine addition after loss of response (LOR) to IFX with the efficacy and safety of an earlier combination of thiopurine and IFX.

METHODS

This retrospective study analyzed patients with CD who started IFX as a first-line biologic at Kyushu University Hospital between June 2002 and July 2018. Patients were assigned to either the early-combination (EC) group, who started IFX and thiopurine simultaneously, or the late-combination (LC) group, who were treated with IFX alone until they developed LOR. We compared the cumulative IFX continuation rates and AE incidence between the two groups.

RESULTS

One hundred seventy-six patients were enrolled in this study; 49 were enrolled in the EC group, and 127 were enrolled in the LC group. Disease activity at baseline did not significantly differ between the groups, nor did the cumulative IFX continuation rates differ between the groups (P = 0.30); however, the AE rate was significantly higher in the EC group than in the LC group (38.7% vs. 21.2%; P = 0.02). The severe AE rate was also higher in the EC group than in the LC group (18.3% vs 3.1%; P = 0.001).

CONCLUSION

Considering the risk-benefit balance, delayed addition of thiopurine after LOR to IFX might be an alternative strategy when using IFX to treat CD.

Is barium enema examination negligible for the management of colorectal cancer? Comparison with conventional colonoscopy and magnifying colonoscopy

PURPOSE

The aim of this investigation was to evaluate the clinical value of barium enema (BE) examination for the management of colorectal epithelial neoplasms.

METHODS

We reviewed the colonoscopy records at our institution from 2014 to 2019 and identified cases of endoscopically or surgically resected colorectal epithelial neoplasms evaluated by BE, conventional colonoscopy, magnifying narrow-band imaging colonoscopy (M-NBI), and magnifying chromoendoscopy (MCE). The yield of each modality for the diagnosis of massively submucosal invasive (mSM) colorectal cancer was evaluated by a receiver-operating characteristic analysis including the area under the curve (AUC).

RESULTS

We analyzed the records of 105 patients (17 adenomas, 53 high-grade dysplasias (HGDs), and 35 cancers). Smooth surface, irregularity in depression, and eccentric deformity on the profile view with BE were observed more frequently in mSM cancers than adenomas/HGDs/slightly submucosal invasive cancers (p < 0.01). The AUC of BE was 0.8355, the value of which was not different from the other three modalities (conventional colonoscopy 0.7678; M-NBI 0.7835; MCE 0.8376). Although the specificity, PPV, and accuracy of BE were lower than those of M-NBI and MCE, the sensitivity and NPV of BE were the highest among the four types of examinations.

CONCLUSION

BE is still available and may serve as a supplementary modality for the diagnosis of mSM cancers.

Rationally designed bacterial consortia to treat chronic immune-mediated colitis and restore intestinal homeostasis

Environmental factors, mucosal permeability and defective immunoregulation drive overactive immunity to a subset of resident intestinal bacteria that mediate multiple inflammatory conditions. GUT-103 and GUT-108, live biotherapeutic products rationally designed to complement missing or underrepresented functions in the dysbiotic microbiome of IBD patients, address upstream targets, rather than targeting a single cytokine to block downstream inflammation responses. GUT-103, composed of 17 strains that synergistically provide protective and sustained engraftment in the IBD inflammatory environment, prevented and treated chronic immune-mediated colitis. Therapeutic application of GUT-108 reversed established colitis in a humanized chronic T cell-mediated mouse model. It decreased pathobionts while expanding resident protective bacteria; produced metabolites promoting mucosal healing and immunoregulatory responses; decreased inflammatory cytokines and Th-1 and Th-17 cells; and induced interleukin-10-producing colonic regulatory cells, and IL-10-independent homeostatic pathways. We propose GUT-108 for treating and preventing relapse for IBD and other inflammatory conditions characterized by unbalanced microbiota and mucosal permeability.

Transethnic analysis of the human leukocyte antigen region for ulcerative colitis reveals not only shared but also ethnicity-specific disease associations

Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gut. Genetic association studies have identified the highly variable human leukocyte antigen (HLA) region as the strongest susceptibility locus for IBD and specifically DRB1*01:03 as a determining factor for ulcerative colitis (UC). However, for most of the association signal such as delineation could not be made because of tight structures of linkage disequilibrium within the HLA. The aim of this study was therefore to further characterize the HLA signal using a transethnic approach. We performed a comprehensive fine mapping of single HLA alleles in UC in a cohort of 9272 individuals with African American, East Asian, Puerto Rican, Indian and Iranian descent and 40 691 previously analyzed Caucasians, additionally analyzing whole HLA haplotypes. We computationally characterized the binding of associated HLA alleles to human self-peptides and analyzed the physicochemical properties of the HLA proteins and predicted self-peptidomes. Highlighting alleles of the HLA-DRB1*15 group and their correlated HLA-DQ-DR haplotypes, we not only identified consistent associations (regarding effects directions/magnitudes) across different ethnicities but also identified population-specific signals (regarding differences in allele frequencies). We observed that DRB1*01:03 is mostly present in individuals of Western European descent and hardly present in non-Caucasian individuals. We found peptides predicted to bind to risk HLA alleles to be rich in positively charged amino acids. We conclude that the HLA plays an important role for UC susceptibility across different ethnicities. This research further implicates specific features of peptides that are predicted to bind risk and protective HLA proteins.

Recent advances in studies of SLCO2A1 as a key regulator of the delivery of prostaglandins to their sites of action

Solute carrier organic anion transporter family member 2A1 (SLCO2A1, also known as PGT, OATP2A1, PHOAR2, or SLC21A2) is a plasma membrane transporter consisting of 12 transmembrane domains. It is ubiquitously expressed in tissues, and mediates the membrane transport of prostaglandins (PGs, mainly PGE₂, PGF_2α, PGD₂) and thromboxanes (e.g., TxB₂). SLCO2A1-mediated transport is electrogenic and is facilitated by an outwardly directed gradient of lactate. PGs imported by SLCO2A1 are rapidly oxidized by cytoplasmic 15-hydroxyprostaglandin dehydrogenase (15-PGDH, encoded by HPGD). Accumulated evidence suggests that SLCO2A1 plays critical roles in many physiological processes in mammals, and it is considered a potential pharmacological target for diabetic foot ulcer treatment, antipyresis, and non-hormonal contraception. Furthermore, whole-exome analyses suggest that recessive inheritance of SLCO2A1 mutations is associated with two refractory diseases, primary hypertrophic osteoarthropathy (PHO) and chronic enteropathy associated with SLCO2A1 (CEAS). Intriguingly, SLCO2A1 is also a key component of the Maxi-Cl channel, which regulates fluxes of inorganic and organic anions, including ATP. Further study of the bimodal function of SLCO2A1 as a transporter and ion channel is expected to throw new light on the complex pathology of human diseases. Here, we review and summarize recent information on the molecular functions of SLCO2A1, and we discuss its pathophysiological significance.

Predictive Factors for Rebleeding after Negative Capsule Endoscopy among Patients with Overt Obscure Gastrointestinal Bleeding

BACKGROUND

Although capsule endoscopy (CE) is useful to evaluate obscure gastrointestinal bleeding (OGIB), CE does not always identify the responsible lesions in patients with overt OGIB.

OBJECTIVES

To identify factors predictive of rebleeding after negative CE in patients with overt OGIB.

METHODS

We retrospectively analyzed the clinical data of 221 patients who underwent CE for overt OGIB. Among 120 patients with negative CE findings, clinical course of 112 patients after CE was followed-up. Clinical factors associated with rebleeding after negative CE and lesions responsible for rebleeding were investigated.

RESULTS

Rebleeding was identified in 37 patients (33.0%) during follow-up after negative CE, and 36 patients (32.1%) developed rebleeding within 24 months after negative CE. Multivariate analyses showed that ongoing overt OGIB (OR 2.67; 95% CI 1.07-5.80; p = 0.036) and severe anemia at the initial CE examination (OR 2.54; 95% CI 1.33-4.96; p = 0.005) were independent factors -associated with rebleeding. Rebleeding source was detected in 13 patients.

CONCLUSIONS

Rebleeding is not a rare condition among patients with overt OGIB after negative CE. Patients with ongoing overt OGIB or severe anemia at the initial CE examination seem to have a higher risk of rebleeding.

Mesenteric phlebosclerosis complicating colonic cancer treated by endoscopic submucosal dissection

A 67-year old woman with a history of long-term Chinese herb use was admitted to our institution complaining of abdominal pain. Barium enema disclosed rigidity of throughout the proximal colon and a slightly elevated lesion in the transverse colon. Colonoscopy showed diffuse and bronze mucosa in the proximal colon, which was compatible with mesenteric phlebosclerosis. There was also a reddish, elevated lesion in the transverse colon. Magnifying colonoscopy revealed irregular microsurface and microvessels on the surface of the lesion. Under a diagnosis of intramucosal cancer, the elevated lesion was treated by endoscopic submucosal dissection. Histological examination of the resected specimen showed intramucosal well-differentiated adenocarcinoma, and fibrous thickening of the vascular wall together with collagen deposition in the submucosa. The final diagnosis was an intramucosal cancer occurring in mesenteric phlebosclerosis.

Genetic Analysis of Ulcerative Colitis in Japanese Individuals Using Population-specific SNP Array

BACKGROUND

To clarify the genetic background of ulcerative colitis (UC) in the Japanese population, we conducted a genome-wide association study (GWAS) using a population-specific single nucleotide polymorphism (SNP) array.

METHODS

We performed a GWAS and replication study including 1676 UC patients and 2381 healthy controls. The probability of colectomy was compared between genotypes of rs117506082, the top hit SNP at HLA loci, by the Kaplan-Meier method. We studied serum expression of miR-622, a newly identified candidate gene, from 32 UC patients and 8 healthy controls by quantitative reverse-transcription polymerase chain reaction.

RESULTS

In the GWAS, only the HLA loci showed genome-wide significant associations with UC (rs117506082, P = 6.69E-28). Seven nominally significant regions included 2 known loci, IL23R (rs76418789, P = 6.29E-7) and IRF8 (rs16940202, P = 1.03E-6), and 5 novel loci: MIR622 (rs9560575, P = 8.23E-7), 14q31 (rs117618617, P = 1.53E-6), KAT6B (rs12260609, P = 1.81E-6), PAX3-CCDC140-SGPP2 (rs7589797, P = 2.87E-6), and KCNA2 (rs118020656, P = 4.01E-6). Combined analysis revealed that IL23R p.G149R (rs76418789, P = 9.03E-11; odds ratio [OR], 0.51) had genome-wide significant association with UC. Patients with GG genotype of rs117506082 had a significantly lower probability of total colectomy than those with the GA+AA genotype (P = 1.72E-2). Serum expression of miR-622 in patients with inactive UC tended to be higher than in healthy controls and patients with active UC (inactive UC vs healthy controls, P = 3.03E-02; inactive UC vs active UC, P = 6.44E-02).

CONCLUSIONS

IL23R p.G149R is a susceptibility locus for UC in Japanese individuals. The GG genotype of rs117506082 at HLA loci may predict a better clinical course.

Short-term and long-term outcomes of indigo naturalis treatment for inflammatory bowel disease

BACKGROUND AND AIM

Indigo naturalis (IN) is a traditional Chinese herbal medicine reported to be effective in inducing remission in ulcerative colitis (UC). We conducted a retrospective observational study to investigate the efficacy and safety of IN for induction and maintenance therapy in patients with inflammatory bowel disease.

METHODS

Data were collected from the electric medical records of patients with inflammatory bowel disease who had started IN treatment between March 2015 and April 2017 at Kyushu University Hospital. Clinical response and remission rates were assessed based on the clinical activity index determined by Rachmilewitz index or Crohn's disease (CD) activity index. Cumulative IN continuation rates were estimated using the Kaplan-Meier method. Overall adverse events (AEs) during follow-up were also analyzed.

RESULTS

Seventeen UC patients and eight CD patients were enrolled. Clinical response and remission rates at week 8 were 94.1% and 88.2% in UC patients and 37.5% and 25.0% in CD patients, respectively. Clinical remission rates, as assessed through non-responders imputation analyses at weeks 52 and 104, were 76.4% and 70.4% in UC patients and 25.0% and 25.0% in CD patients, respectively. Ten patients (40%) experienced AEs during follow-up. Three patients (12%) experienced severe AEs, including acute colitis requiring hospitalization in two patients and acute colitis with intussusception requiring surgery in one patient.

CONCLUSIONS

Indigo naturalis showed favorable therapeutic efficacy in UC, whereas its therapeutic efficacy in CD appeared to be modest. The risk of severe AEs should be recognized for IN treatment.

Characteristic Facial Appearance Was the Key to Diagnosing Chronic Enteropathy Associated with SLCO2A1-associated Primary Hypertrophic Osteoarthropathy

Patients with chronic enteropathy associated with SLCO2A1 (CEAS) develop multiple circular, longitudinal, or eccentric ulcers in the ileum. It is sometimes difficult to distinguish CEAS from Crohn's disease. CEAS and primary hypertrophic osteoarthropathy (PHO) are together known to be caused by a mutation of SLCO2A1 gene. The case of a 65-year-old man whose characteristic appearance due to pachydermia of the forehead folds led to the diagnosis of CEAS with PHO is presented.

Mucosal dysbiosis in patients with gastrointestinal follicular lymphoma

Because the pathogenesis of gastrointestinal follicular lymphoma (GI-FL) remains unclear, no standardized treatment strategy has been established. Of the gastrointestinal lymphomas, gastric mucosa-associated lymphoid tissue lymphomas are strongly associated with Helicobacter pylori; hence, the microbiota may be involved in GI-FL pathogenesis. However, the association between GI-FL and the microbiota remains uninvestigated. Therefore, we compared the mucosal microbiotas of GI-FL patients with those of controls to identify microbiota changes in GI-FL patients. Mucosal biopsy samples were obtained from the second portion of the duodenum from 20 GI-FL patients with duodenal lesions and 20 controls. Subsequent 16S rRNA gene sequencing was performed on these samples. QIIME pipeline and LEfSe software were used to analyze the microbiota. The GI-FL patients had significantly lower alpha diversity (P = .049) than did the controls, with significant differences in the microbial composition (P = .023) evaluated by the beta diversity metrics between the two groups. Comparing the taxonomic compositions indicated that the genera Sporomusa, Rothia, and Prevotella and the family Gemellaceae were significantly less abundant in the GI-FL patients than in the controls. GI-FL patients presented altered duodenal mucosal microbial compositions, suggesting that the microbiota might be involved in the GI-FL pathogenesis.

Chronic Enteropathy Associated with SLCO2A1 with Pachydermoperiostosis

A 49-year-old man complained of chronic palpitation and shortness of breath, which had recently become exacerbated. A blood examination indicated severe refractory anemia and hypoproteinemia. Physical examinations revealed anemia, a systolic murmur, and spoon nails. Multiple nonspecific ileal ulcers were observed. A pathological examination indicated a small granuloma with CD68-positive histiocytes. He had a deeply wrinkled forehead, chiseled face, and clubbed fingers. Radiography revealed periostosis of the fingers and long bones in the limb. He was diagnosed with pachydermoperiostosis. SLCO2A1 demonstrated a c.1807C>T homo-mutation. He was also diagnosed with SLCO2A1-associated chronic enteropathy and thus was treated with 5-aminosalicylic acid, which temporarily improved the ileal ulcers, anemia, and hypoalbuminemia.

Risk factors for reflux esophagitis after eradication of Helicobacter pylori

Objective: While there is an association between successful eradication of Helicobacter pylori (HP) and reflux esophagitis (RE), risk factors associated with RE remain obscure. The aim of this study is to determine risk factors associated with the development of RE after HP eradication.Materials and methods: Among all patients treated with successful HP eradication from 2008 to 2016, we retrospectively analyzed those who were free from RE at initial esophagogastroduodenoscopy (EGD) and who were followed up with EGD after eradication. Patients were classified according to the presence or absence of RE at the follow-up EGD. RE was defined as mucosal breaks proximal to the squamous-columnar junction. Demographic data, underlying diseases, medications and endoscopic findings at the initial EGD were compared between patients with and without RE.Results: Among 1575 patients, 142 (9.0%) had RE at the follow-up EGD. The time interval from HP eradication until EGD ranged from 4 to 24 months. The endoscopic grade of RE was higher in males than in females. Multivariate analysis revealed that male sex (odds ratio [OR], 1.51; 95% confidence interval [CI], 1.04-2.24), body mass index ≥25 kg/m² (OR, 2.91; 95% CI, 2.00-4.22), use of calcium channel blockers (OR, 1.70; 95% CI, 1.12-2.55), and hiatal hernia (OR, 3.46; 95% CI, 2.41-5.00) were associated with the development of RE.Conclusions: Calcium channel blocker use was found to be a risk factor for the development of RE after eradication of HP.

Endoscopic features of gastrointestinal stromal tumor in the small intestine

Background/Aims

Gastrointestinal stromal tumor (GIST) is one of the most common types of submucosal tumors (SMTs). Because of GIST’s malignant potential, it is crucial to differentiate it from other SMTs. The present study aimed to identify characteristic endoscopic findings of GISTs in the small intestine.

Methods

We reviewed the clinicopathological and endoscopic findings of 38 patients with endoscopically or surgically resected SMTs in the small intestine. SMTs were classified into GIST and non-GIST groups, and clinicopathological and endoscopic findings were compared between the 2 groups.

Results

Fifteen patients had GIST and 23 patients had other types of SMTs in the small intestine. Comparison of the endoscopic findings between the 2 groups revealed that dilated vessels in the surrounding mucosa were significantly more in number in the GIST group than in the non-GIST group (P<0.05). However, there were no other differences in endoscopic findings between the 2 groups. Among patients with GISTs, the presence of dilated vessels in the surrounding mucosa was not associated with bleeding risk, tumor size, or metastasis rate at diagnosis.

Conclusions

Dilated vessels in the surrounding mucosa, identified during balloon-assisted endoscopy, may be a diagnostic indicator for GIST in the small intestine. However, its clinical significance should be further analyzed.

Distinction between Chronic Enteropathy Associated with the SLCO2A1 Gene and Crohn's Disease

Background/Aims

We recently identified recessive mutations in the solute carrier organic anion transporter family member 2A1 gene (SLCO2A1) as causative variants of chronic nonspecific multiple ulcers of the small intestine (chronic enteropathy associated with SLCO2A1, CEAS). The aim of this study was to investigate the gastroduodenal expression of the SLCO2A1 protein in patients with CEAS and Crohn’s disease (CD).

Methods

Immunohistochemical staining for SLCO2A1 was performed with a polyclonal antibody, HPA013742, on gastroduodenal tissues obtained by endoscopic biopsy from four patients with CEAS and 29 patients with CD.

Results

The expression of SLCO2A1 was observed in one of four patients (25%) with CEAS and in all 29 patients (100%) with CD (p<0.001). The three patients with CEAS without SLCO2A1 expression had a homozygous splice-site mutation in SLCO2A1, c.1461+1G>C (exon 7) or c.940+1G>A (exon 10). The remaining one CEAS patient with positive expression of SLCO2A1 had compound heterozygous c.664G>A and c.1807C>T mutations.

Conclusions

Immunohistochemical staining for SLCO2A1 in gastroduodenal tissues obtained by endoscopic biopsy is considered useful for the distinction of CEAS from CD.

Measurement of prostaglandin metabolites is useful in diagnosis of small bowel ulcerations

BACKGROUND

We recently reported on a hereditary enteropathy associated with a gene encoding a prostaglandin transporter and referred to as chronic enteropathy associated with SLCO2A1 gene (CEAS). Crohn’s disease (CD) is a major differential diagnosis of CEAS, because these diseases share some clinical features. Therefore, there is a need to develop a convenient screening test to distinguish CEAS from CD.

AIM

To examine whether prostaglandin E major urinary metabolites (PGE-MUM) can serve as a biomarker to distinguish CEAS from CD.

METHODS

This was a transactional study of 20 patients with CEAS and 98 patients with CD. CEAS was diagnosed by the confirmation of homozygous or compound heterozygous mutation of SLCO2A1. We measured the concentration of PGE-MUM in spot urine by radioimmunoassay, and the concentration was compared between the two groups of patients. We also determined the optimal cut-off value of PGE-MUM to distinguish CEAS from CD by receiver operating characteristic (ROC) curve analysis.

RESULTS

Twenty Japanese patients with CEAS and 98 patients with CD were enrolled. PGE-MUM concentration in patients with CEAS was significantly higher than that in patients with CD (median 102.7 vs 27.9 μg/g × Cre, P < 0.0001). One log unit increase in PGE-MUM contributed to 7.3 increase in the likelihood for the diagnosis of CEAS [95% confidence interval (CI) 3.2-16.7]. A logistic regression analysis revealed that the association was significant even after adjusting confounding factors (adjusted odds ratio 29.6, 95%CI 4.7-185.7). ROC curve analysis revealed the optimal PGE-MUM cut-off value for the distinction of CEAS from CD to be 48.9 μg/g × Cre with 95.0% sensitivity and 79.6% specificity.

CONCLUSION

PGE-MUM measurement is a convenient, non-invasive and useful test for the distinction of CEAS from CD.

A Genome-wide Association Study Identifying RAP1A as a Novel Susceptibility Gene for Crohn's Disease in Japanese Individuals

BACKGROUND AND AIMS

Genome-wide association studies [GWASs] of European populations have identified numerous susceptibility loci for Crohn's disease [CD]. Susceptibility genes differ by ethnicity, however, so GWASs specific for Asian populations are required. This study aimed to clarify the Japanese-specific genetic background for CD by a GWAS using the Japonica array [JPA] and subsequent imputation with the 1KJPN reference panel.

METHODS

Two independent Japanese case/control sets (Tohoku region [379 CD patients, 1621 controls] and Kyushu region [334 CD patients, 462 controls]) were included. GWASs were performed separately for each population, followed by a meta-analysis. Two additional replication sets [254 + 516 CD patients and 287 + 565 controls] were analysed for top hit single nucleotide polymorphisms [SNPs] from novel genomic regions.

RESULTS

Genotype data of 4 335 144 SNPs from 713 Japanese CD patients and 2083 controls were analysed. SNPs located in TNFSF15 (rs78898421, Pmeta = 2.59 × 10-26, odds ratio [OR] = 2.10), HLA-DQB1 [rs184950714, pmeta = 3.56 × 10-19, OR = 2.05], ZNF365, and 4p14 loci were significantly associated with CD in Japanese individuals. Replication analyses were performed for four novel candidate loci [p <1 × 10-6], and rs488200 located upstream of RAP1A was significantly associated with CD [pcombined = 4.36 × 10-8, OR = 1.31]. Transcriptome analysis of CD4+ effector memory T cells from lamina propria mononuclear cells of CD patients revealed a significant association of rs488200 with RAP1A expression.

CONCLUSIONS

RAP1A is a novel susceptibility locus for CD in the Japanese population.

Anti-tumor necrosis factor therapy decreases the risk of initial intestinal surgery after diagnosis of Crohn's disease of inflammatory type

BACKGROUND

Anti-tumor necrosis factor (TNF) therapy induces and maintains clinical remission in patients with Crohn's disease (CD). However, the effect of anti-TNF therapy on the natural course of CD remains controversial. We aimed to investigate the effect of anti-TNF therapy on the initial intestinal surgery for CD.

METHODS

In this single-center retrospective cohort study, clinical course of 199 CD patients of inflammatory type at the initial diagnosis (the period between 1973 and 2014) was precisely reviewed until the end of 2016. Patients were divided into TNF and non-TNF groups based on anti-TNF agent use. After comparisons of clinical characteristics and medical treatments, propensity scores were calculated for covariates. Risk of intestinal surgery was compared by a Cox proportional hazards model using the propensity scores. The effect of immunomodulators on initial intestinal surgery was assessed in the TNF group.

RESULTS

During the study period, 108 patients received anti-TNF therapy. The patients in the TNF group were diagnosed more recently, and more frequently had isolated colonic involvement, and perianal disease. Immunomodulators were more frequently used in the TNF group. Cumulative probability of initial intestinal surgery was significantly lower in the TNF group (P < 0.0001). The hazard ratio in the TNF group was 0.32 (95% CI 0.13-0.74). Immunomodulators did not decrease the risk of initial intestinal surgery.

CONCLUSIONS

Anti-TNF therapy can decrease the risk of intestinal surgery among patients with inflammatory-type CD at the initial diagnosis. Further studies should be necessary to determine the additive effect of immunomodulators on the risk of intestinal surgery.

Risk of surgery in patients with stricturing type of Crohn's disease at the initial diagnosis: a single center experience

BACKGROUND/AIMS

It remains uncertain which patients with stricturing-type Crohn's disease (CD) require early small bowel surgery after the initial diagnosis. We aimed to clarify clinical characteristics associated with the intervention in such condition of CD.

METHODS

We retrospectively evaluated the clinical course of 53 patients with CD and small bowel strictures who were initially treated with medications after the initial diagnosis. We investigated possible associations between small bowel surgery and the following: clinical factors and radiologic findings at initial diagnosis and the types of medications administered during follow-up.

RESULTS

Twenty-eight patients (53%) required small bowel resection during a median follow-up period of 5.0 years (range, 0.5-14.3 years). The cumulative incidence rates of small bowel surgery at 2, 5, and 10 years were 26.4%, 41.0%, and 63.2%, respectively. Univariate analysis indicated that obstructive symptoms (P=0.036), long-segment stricture (P<0.0001), and prestenotic dilation (P<0.0001) on radiography were associated with small bowel surgery, and immunomodulatory (P=0.037) and biological therapy (P=0.008) were significant factors during follow-up. Multivariate analysis revealed that long-segment stricture (hazard ratio [HR], 4.25; 95% confidence interval [CI], 1.78-10.53; P=0.001) and prestenotic dilation (HR, 3.41; 95% CI, 1.24-9.62; P=0.018) on radiography showed a positive correlation with small bowel surgery, and biological therapy (HR, 0.40; 95% CI, 0.15-0.99; P=0.048) showed a negative correlation.

CONCLUSIONS

CD patients with long-segment stricture and prestenotic dilation on radiography seem to be at a higher risk of needing small bowel surgery. For such patients, early surgical intervention might be appropriate, even at initial diagnosis.