Background/Aims : International consensus guidelines recommend assessing the external anal sphincter (EAS) function using a short maximal contraction. The clinical value of sustained contractions for assessing EAS fatigability remains controversial, partly because most studies have used water-perfused anorectal manometry systems rather than the more recent three-dimensional high-resolution anorectal manometry (3D HR-ARM) approach. We aimed to determine the discriminative ability of EAS fatigability between patients with fecal incontinence (FI) and healthy volunteers (HV), as well as its pathophysiological implications in patients with FI assessed using 3D HR-ARM. Methods : 3D HR-ARM data from 160 adult female with FI (median age, 64 years) were compared with data from 39 healthy female volunteers (median age, 52 years; P < 1.10-3). EAS fatigability was assessed during a long squeeze (LS) using mean incremental LS pressure (LSP), LS duration, fatigue rate index, and contractile integral (CI). Patients additionally underwent endoanal ultrasound and anal sphincter electromyography. The discriminative performance was evaluated through repeated cross-validation using logistic regression and classification and regression tree models. Results : The most discriminative model for distinguishing FI from HV combined resting pressure (RP) with maximal incremental LSP (area under the ROC curve [AUROC], 0.82; sensitivity, 0.91; specificity, 0.72). RP combined with LS duration showed similar discrimination, but lower specificity (AUROC, 0.82; sensitivity, 0.94; specificity, 0.44). Maximal incremental short squeeze pressure and maximal incremental LSP were associated with neuropathic processes (P = 0.031 and P = 0.034, respectively). Conclusions : EAS fatigability during LS, assessed using 3D HR-ARM, did not discriminate between patients with FI and HV, nor did it identify specific pathophysiological mechanisms.
Background/Aims : Peroral endoscopic myotomy (POEM) is an effective and safe treatment for patients with achalasia; however, it is associated with reflux esophagitis after treatment. This study aimed to examine underlying acidification patterns in patients with achalasia with reflux esophagitis after POEM. Methods : Data were used from a large multicenter randomized controlled trial comparing the effects of POEM and pneumatic dilation in treatment of naive patients with achalasia. Gastroduodenoscopy and 24-hour pH-impedance testing were performed 1 year post-POEM. Acid exposure time (AET), mean pH, minimum pH, and acidification patterns such as reflux, acid fermentation and stasis of acidic foods were compared between patients with endoscopically proven gastroesophageal reflux disease (GERD; LA grade B-D) and those without. Results : In total 38 patients were included of which 9 had endoscopically proven GERD (23.7%). AET and mean pH levels were not different between patients with and without proven GERD (14.5% vs. 6.0%, P = 0.636 and 5.4 vs. 5.2, P = 0.747, respectively). Patients with reflux esophagitis grade B-D reached lower minimum pH (1.5 vs. 2.1, P = 0.024) and had significantly longer episodes of reflux with delayed clearance, particularly in the supine position (7.7% vs. 0.0%, P = 0.041). Acid fermentation was seen in a large proportion of patients, but was not significantly different between patients with and without proven GERD (10.2% vs. 0.4%, P = 0.343). Conclusions : Reflux with delayed clearance in supine position appeared to be the dominant acidification pattern in patients with achalasia and reflux esophagitis after POEM.
Background/Aims : Recent studies show that the gut microbiota may affect both small-intestinal motility and metabolic dysfunction-associated steatotic liver disease (MASLD). However, human studies of this triangle are lacking. Our aim was to leverage the unique potential of cine-MRI to quantify small-intestinal motility in patients with MASLD and investigate its association with gut microbiota, metabolic tissues and metabolites. Methods : Fifteen patients with histology proven MASLD participated in a 12-week exercise intervention. At baseline and endpoint, small-intestinal motility and liver status were assessed using MRI. Stool consistency and composition of fecal microbiome as well as mRNA expression of liver, skeletal muscle, and subcutaneous adipose tissue biopsies were studied. Non-targeted metabolomics was performed on stool, fasted plasma, and urine samples. Results : At baseline, small-intestinal motility did not correlate to liver histology scores or MRI-determined markers of liver fat, stiffness, or inflammation. However, small-intestinal motility did correlate with fecal microbiota, including Verrucomicrobia and Bacteroidetes phyla as well as 41 species such as Prevotella species incertae sedis (false discovery rate [FDR]-P < 0.2). Moreover, liver RNA sequencing revealed correlations of small-intestinal motility with liver mRNA expression of CBS (FDR-P < 0.001), linked to hydrogen sulfide production, and adipose tissue mRNA expression of SCARB1 and SCD1 (FDR-P < 0.05), involved in lipid metabolism. Several stool, plasma, and urine metabolites correlated with small-intestinal motility. Exercise had no effect. Conclusions : In MASLD patients, small-intestinal motility associates with gut microbiota, metabolites and mRNA expression in metabolic tissues. These findings warrant further investigation to determine causality and effect directionality. Additionally, this exploratory study demonstrates the potential of cine-MRI for fundamental small-intestinal motility research.
Background/Aims : Prospective data regarding small-intestinal bacterial overgrowth (SIBO) in patients with Crohn's disease (CD) are limited, and the influence of small-bowel strictures on SIBO as well as the effects of stricture-directed interventions remain unclear. Methods : Patients with CD were classified into stricture and non-stricture groups on the basis of the findings of double-balloon enteroscopy or cross-sectional imaging. Healthy controls (HCs) were included. All participants underwent glucose hydrogen-methane breath testing, and SIBO was diagnosed according to the North American Consensus criteria. Primary analyses used pre-intervention tests, whereas secondary analyses assessed changes after endoscopic balloon dilation (EBD) or surgery. Results : Hydrogen-type SIBO (H-SIBO) was not detected in HCs (0/33) but was observed in 3 of 32 patients with CD (9.4%; P = 0.114). H-SIBO was observed in patients with strictures (3/17) but not in those without strictures (0/15; P = 0.229). Three patients who initially showed negative results for H-SIBO showed positive results after EBD of the ileum or ileal surgery; thus, H-SIBO was observed in 6/32 CD cases (18.8%; P = 0.011 vs. HCs; sensitivity analysis including post-intervention tests). Methane-type SIBO was detected in one HC participant (1/33) but was not observed in patients with CD before or after the intervention. Conclusions : In this prospective cohort study, the prevalence of H-SIBO in Japanese patients with CD appeared to be lower than that reported previously. Severe small-bowel strictures may cause false-negative glucose breath-test results, and stricture-directed interventions may reveal previously undetectable bacterial overgrowth. These findings indicate dynamic changes in SIBO status following such interventions, although the results should be interpreted with caution given the limited sample size and methodological constraints.
