Relationship between the gut microbiota and bile acid composition in the ileal mucosa of Crohn’s disease

Background/Aims@#Crosstalk between the gut microbiota and bile acid plays an important role in the pathogenesis of gastrointestinal disorders. We investigated the relationship between microbial structure and bile acid metabolism in the ileal mucosa of Crohn’s disease (CD). @*Methods@#Twelve non-CD controls and 38 CD patients in clinical remission were enrolled. Samples were collected from the distal ileum under balloon-assisted enteroscopy. Bile acid composition was analyzed by liquid chromatography-mass spectrometry. The gut microbiota was analyzed by 16S rRNA gene sequencing. @*Results@#The Shannon evenness index was significantly lower in endoscopically active lesions than in non-CD controls. β-Diversity, evaluated by the UniFrac metric, revealed a significant difference between the active lesions and non-CD controls (P=0.039). The relative abundance of Escherichia was significantly higher and that of Faecalibacterium and Roseburia was significantly lower in CD samples than in non-CD controls. The increased abundance of Escherichia was more prominent in active lesions than in inactive lesions. The proportion of conjugated bile acids was significantly higher in CD patients than in non-CD controls, but there was no difference in the proportion of primary or secondary bile acids. The genera Escherichia and Lactobacillus were positively correlated with the proportion of conjugated bile acids. On the other hand, Roseburia, Intestinibacter, and Faecalibacterium were negatively correlated with the proportion of conjugated bile acids. @*Conclusions@#Mucosa-associated dysbiosis and the alteration of bile acid composition were identified in the ileum of CD patients. These may play a role in the pathophysiology of ileal lesions in CD patients.

Prototype single-balloon enteroscopy with passive bending and high force transmission improves depth of insertion in the small intestine

Background/Aims@#We retrospectively analyzed Crohn’s disease (CD) patients with small intestinal strictures who underwent single-balloon enteroscopy (SBE) to ascertain whether prototype SBEs with a passive bending mechanism and high force transmission insertion tube had better insertability in the small intestine than a conventional SBE. @*Methods@#Among 253 CD patients who underwent SBE, we identified 94 CD patients who had undergone attempted endoscopic balloon dilatation (EBD) for small intestinal stenosis for inclusion in this study. We analyzed whether the type of scope used for their initial procedure affected the cumulative surgery-free rate. For the insertability analysis, patients who underwent SBE at least twice were divided into 3 groups according to the type of scope used: conventional SBE only, prototype SBE only, and both conventional and prototype SBEs. For each group, depth of insertion, procedure time, and number of EBDs were compared in the same patient at different time points. @*Results@#The success rate of EBD was 88.3%. The 5- and 10-year cumulative surgery-free rate was 75.7% and 72.8%, respectively. Cox regression analysis indicated that the factors contributing to surgery were long stricture (≥2 cm), EBD failure, and elevated Crohn’s Disease Activity Index, but not the type of scope used for EBD. The prototype SBEs significantly improved the depth of insertion (P=0.03, Wilcoxon’s signed-rank test). @*Conclusions@#In CD patients with small intestinal stenosis, the prototype SBEs with a passive bending mechanism and high force transmission insertion tube did not improve long-term EBD outcome but did improve deep insertability. (Clinical Trial Registration No. UMIN000037102)

Efficacy and safety of cold forceps polypectomy utilizing the jumbo cup: a prospective study

BACKGROUND/AIMS: There are few prospective studies on cold forceps polypectomy (CFP) using jumbo cup forceps. Therefore, we examined patients with diminutive polyps (5 mm or smaller) treated with CFP using jumbo cup forceps to achieve an adenoma-free colon and also assessed the safety of the procedure and the recurrence rate of missed or residual polyp after CFP by performing follow-up colonoscopy 1 year later. METHODS: We included patients with up to 5 adenomas removed at initial colonoscopy and analyzed data from a total of 361 patients with 573 adenomas. One-year follow-up colonoscopy was performed in 165 patients, at which 251 lesions were confirmed. RESULTS: The one-bite resection rate with CFP was highest for lesions 3 mm or smaller and decreased significantly with increasing lesion size. Post-procedural hemorrhage was observed in 1 of 573 lesions (0.17%). No perforation was noted. The definite recurrence rate was 0.8% (2/251 lesions). The probable recurrence rate, which was defined as recurrence in the same colorectal segment, was 17%. Adenoma-free colon was achieved in 55% of patients at initial resection. Multivariate analysis revealed that achievement of an adenoma-free colon was significantly associated with number of adenomas and years of endoscopic experience. CONCLUSIONS: CFP using jumbo biopsy forceps was safe and showed a high one-bite resection rate for diminutive lesions of 3 mm or smaller. The low definite recurrence rate confirms the reliability of CFP using jumbo biopsy forceps. Number of adenomas and years of endoscopic experience were key factors in achieving an adenoma-free colon.

Seven days triple therapy for eradication of Helicobacter pylori does not alter the disease activity of patients with inflammatory bowel disease

BACKGROUND/AIMS: The influences of Helicobacter pylori eradication therapy on the disease course of inflammatory bowel disease (IBD) are still unclear. We therefore conducted a multicenter, retrospective cohort study to evaluate the safety of H. pylori eradication therapy for IBD patients. METHODS: IBD patients with H. pylori eradication from 2005 to 2015 (eradication group) and control patients (non-eradication group; 2 paired IBD patients without H. pylori eradication matched with each eradicated patient) were included. IBD exacerbation (increased/additional IBD drug or IBD-associated hospitalization/surgery) and disease improvement based on the physicians’ global assessment were investigated at baseline, and at 2 and 6 months after eradication or observation. RESULTS: A total of 429 IBD (378 ulcerative colitis, 51 Crohn’s disease) patients, comprising 144 patients in the eradication group and 285 patients in the non-eradication group, were enrolled at 25 institutions. IBD exacerbation was comparable between groups (eradication group: 8.3% at 2 months [odds ratio, 1.76; 95% confidence interval, 0.78–3.92; P=0.170], 11.8% at 6 months [odds ratio, 1.60; 95% confidence interval, 0.81–3.11; P=0.172]). Based on the physicians’ global assessment at 2 months, none of the patients in the eradication group improved, whereas 3.2% of the patients in the non-eradication group improved (P=0.019). Multivariate analysis revealed that active disease at baseline, but not H. pylori eradication, was an independent factor for IBD exacerbation during 2 months’ observation period. The overall eradication rate was 84.0%–comparable to previous reports in non-IBD patients. CONCLUSIONS: H. pylori eradication therapy does not alter the short-term disease activity of IBD.

Magnified single-balloon enteroscopy in the diagnosis of intestinal follicular lymphoma: a case series

The objective of this study was to evaluate the magnified endoscopic findings in the diagnosis of follicular lymphoma in the small intestine in comparison with those of intestinal follicular lymphoma and lymphangiectasia. Four patients with follicular lymphoma and 3 with lymphangiectasia in the small intestine were retrospectively analyzed. A prototype magnifying singleballoon enteroscope was used. The findings of the intestinal follicular lymphoma and lymphangiectasia were retrospectively analyzed to determine the magnified endoscopic findings of follicular lymphoma in the small intestine. Opaque white granules were observed in 3 of the 4 patients with follicular lymphoma. Magnified narrow-band imaging (NBI) of the opaque white granules showed stretched microvessels, which had a diminutive tree-like appearance. The remaining patient had no opaque white granules and only displayed whitish villi. Magnified NBI observation of the whitish villi revealed the absence of marginal villus epithelium, which was confirmed by histology. The magnified NBI enteroscopy revealed the diminutive tree-like appearance on the opaque white granules and the absence of marginal villus epithelium of the whitish villi in intestinal follicular lymphoma. These findings may be useful in diagnosing follicular lymphoma.