Digestion最新文献

Background: Microbes residing in the gastrointestinal tract are intertwined with the immune development and overall health of the host throughout stages of life. It is well established that these microbes can have both positive and negative impacts on host health. Having foundational knowledge of these interactions with the host is critical in understanding gastrointestinal health.

Summary: This review discusses the importance of high-resolution study of the gut microbiota, which includes potential modern approaches for analyzing the gut microbiota and considers the challenges and aspects necessary for robust investigation of the gut microbiota. Here, we highlight the complex and highly individualized relationship of microbes interacting within the host results in an ever-changing landscape in the gastrointestinal tract, whether due to host conditions or microbial conditions including microbe-microbe and microbe-host interactions. The vastness and complexity of the gut microbiota contribute to the challenge of quantifying not only a community of microbes in the gut environment, but also maintaining resolution to investigate individual microbes, capturing the network of interactions coinciding in the gastrointestinal tract. Furthermore, the review emphasizes the importance of microbial functions and products to host health outcomes in the context of inflammatory diseases.

Key messages: Consideration for microbial functions and interactions with the gut immune system is critical for developing effective treatment strategies of inflammatory disorders. Employing high-resolution microbial techniques to investigate microbes with environmental relevance and community functions are a major challenge in the microbiome field. With new techniques and improvements on existing methodologies, investigating microbes at various community levels is feasible and becoming critical in understanding the community interactions with the host influencing the immune status and overall health outcomes.

Introduction: Studies have demonstrated clinical benefits of fecal microbiota transplantation (FMT) for treatment of irritable bowel syndrome (IBS). This study aimed to evaluate the cost-effectiveness of FMT versus standard drug treatment for patients with moderate-to-severe IBS who failed to respond to first-line therapy from the US payer's perspective.

Methods: Two 1-year Markov models were developed to examine the outcomes of FMT versus standard drug treatment in patients with constipation-predominant IBS (IBS-C) and diarrhea-predominant IBS (IBS-D). The primary model outcomes included direct medical cost and quality-adjusted life-years (QALYs) gained. Model inputs were obtained from literature and public data. Sensitivity analyses were performed to examine the robustness of model results.

Results: In the base-case analysis, FMT gained higher QALYs (by 0.0159 QALYs for IBS-C and 0.0166 QALYs for IBS-D) with cost savings (USD 7,835 for IBS-C and USD 9,015 for IBS-D) when compared to standard drug treatment. Key influential parameters identified by one-way sensitivity analysis were response probabilities of FMT and first-line treatment, the utility values of therapeutic response and nonresponse, and FMT cost. The probabilities of FMT to be accepted as the preferred strategy at a willingness-to-pay threshold of USD 50,000/QALY were 99.86% and 99.89% for IBS-C and IBS-D, respectively.

Conclusion: FMT appears to be cost-effective for patients with moderate-to-severe IBS who failed to respond to first-line therapy from the US payer's perspective.

Introduction: Early detection of duodenal neoplasms is crucial because of the complications associated with their treatment and their increasing recognition. However, standardised protocols for duodenal observation during screening esophagogastroduodenoscopy (EGD) have not been established. This study was performed to survey the current practical status of duodenal observation and to evaluate the clinical relevance of our systematic photo-documentation protocol, known as the Seven Pictures Rule (7 PR).

Methods: A cross-sectional survey using a web-based self-administered questionnaire was conducted among endoscopists in a regional area of Japan. The questionnaire included items on respondents' professional background, duodenal observation practices during screening EGD (observed locations, observation time, ampulla visualisation, and patient discomfort), as well as awareness, application, and perceived effects of the 7 PR, and preferences for future protocols. Data were anonymised and analysed descriptively.

Results: Of the 99 endoscopists included, 96.7% reported observing the duodenum based on their own individual methods. The intentional observation rates by location were highest in the following order: bulb (99%), ampulla in descending (94%), contralateral ampulla in descending (84%), superior duodenal angle (77%), contralateral superior duodenal angle (79%), and transverse duodenum (33%). However, only 14% of respondents reported successfully observing the ampulla in more than 75% of cases. While 62% were aware of the 7 PR, only one-fourth had implemented it in practice. Notably, 43% of respondents familiar with the 7 PR felt that it had led to an increased detection of duodenal neoplasms.

Conclusions: Current duodenal observation practices vary among endoscopists. The establishment of a systematic photo-documentation protocol such as the 7 PR may serve as a useful strategy for improving the detection of duodenal neoplasms. Further optimisation of the protocol is warranted to support broader adoption in clinical settings.

In the article entitled "Colonization of Streptococcus pyogenes Is Associated with Functional Dyspepsia and Exacerbates Functional Dyspepsia in Mice by Inhibiting the RhoA/ROCK1 Pathway through the Skin-Gut Axis" by Lin et al. [Digestion. 2025; https://doi.org/10.1159/000545005], an error occurred in the author details listed in the supplementary material.The corrected supplementary material has been updated accordingly.

Background: Artificial intelligence (AI) has progressed rapidly in gastroenterology, especially in colonoscopy, which is well positioned to benefit from AI due to the high global procedure volume and variability in quality across operators. In this review, we summarise the latest updates in the field, its current benefits, and further work required to accelerate its translation in day-to-day clinical practice.

Summary: Computer-aided detection systems are the most established AI system in colonoscopy, with robust evidence from randomised controlled trials showing significant improvements in adenoma detection rates. However, translation into real-world clinical practice has been less impactful, hindered by implementation challenges and lack of reimbursement pathways. Computer-aided diagnosis systems aim to support histological decision-making for diminutive polyps but have shown inconsistent benefits in clinical trials, reflecting complex human-computer interactions. Computer-aided quality systems, while in earlier stages, hold promise for standardising quality metrics. Novel applications in IBD demonstrate the potential of AI to standardise disease activity scoring and predict relapse, while therapeutic applications remain in proof-of-concept phases.

Key messages: Successful adoption of AI will depend on seamless workflow integration, better understanding of human-AI interaction, cost-effectiveness, establishing reimbursement and training pathways, clinician endorsement, and frameworks addressing fairness, accountability, and bias. The more distant future directions are likely to involve fully integrated multi-modal AI systems, personalised surveillance, and AI-assisted therapeutic interventions.

Introduction: Functional abdominal bloating (FAB) is a bowel disorder of gut-brain interaction (DGBI) characterized by predominant bloating symptom. Given gas dynamics in the digestive tract, gas-related symptoms (belching and flatulence) and behaviors may contribute to the development of FAB. This study aimed to examine their relationships.

Methods: We conducted an Internet survey for individuals aged from 18 to 79 years using a questionnaire including items on demographic and clinical characteristics, lifestyle, and gas-related symptoms and behaviors. DGBIs including FAB were diagnosed based on the Rome IV criteria. The severity of bloating was assessed using visual analog scale. Health-related quality of life (HRQOL) was evaluated using the SF-8. Logistic and multiple regression analyses identified factors associated with FAB and their bloating severity.

Results: A total of 9,995 individuals were included in the analysis, in which 123 (1.2%) were classified as having FAB. HRQOL was significantly impaired in the FAB group compared to the non-FAB group. Multivariable analysis demonstrated that gas-related symptoms and behaviors such as frequent flatulence (OR: 2.55, 95% CI: 1.74-3.72, p < 0.001), frequent suppression of flatulence (OR: 2.09, 95% CI: 1.32-3.32, p = 0.002), and resisting the urge to defecate (OR: 2.77, 95% CI: 1.57-4.90, p < 0.001) were significantly and independently associated with an increased odds of FAB, in addition to lower BMI and gastroesophageal reflux disease. Younger age and resisting the urge to defecate were related to increased severity of bloating in patients with FAB.

Conclusion: Gas-related symptoms and behaviors may contribute to the pathophysiology of FAB.

Introduction: Gastric subepithelial tumors (SETs) including gastrointestinal mesenchymal tumors (GIMTs) - which often appear as similar hypoechoic lesions originating from the fourth layer of the gastric wall - are difficult to distinguish with endoscopic ultrasound (EUS). We aimed to prospectively validate the utility of circularity, a surrogate indicator of roundness, as a diagnostic method for SETs.

Methods: Among 100 patients with potential GIMTs sized 1-5 cm prospectively recruited at two institutions between 2020 and 2023, those who experienced pathological diagnosis were included in the final analysis. One representative EUS image showing the tumors' maximum cross-sectional surface was selected, and the circularity was measured using an image analysis software. The circularity of the leiomyoma and other SETs suspected GIMTs was compared, and the diagnostic performance at the optimal cutoff value was evaluated.

Results: In the 62 patients, the number of GIST, leiomyomas, and other SETs were 46, 10, and 6, respectively. Circularity was significantly lower in the leiomyoma group than in the other SETs group (0.846 vs. 0.924). The area under the receiver operating characteristic curve of circularity for predicting leiomyomas was 0.822 when the cutoff value was set to 0.869. When the lesion was diagnosed as leiomyoma with a circularity of <0.869, the accuracy, sensitivity, and specificity were 82.3%, 70%, and 84.6%, respectively.

Conclusion: The noninvasive diagnostic method for SETs based on circularity is useful for excluding leiomyomas in lesions of 1-5 cm in size. This diagnostic method may be a potential adjunctive option for differentiating SETs.

Background: With the improvement in living standards, metabolic dysfunction-associated steatotic liver disease (MASLD) has become the most common chronic liver disease worldwide, garnering increasing concern due to its significant health risks. MASLD encompasses a spectrum of pathological processes ranging from simple steatosis to nonalcoholic steatohepatitis, liver fibrosis, cirrhosis, and even hepatocellular carcinoma, and it has become a leading cause of liver-related mortality. Due to the lack of specific therapeutic targets, current diagnostic, treatment, and management strategies for MASLD remain inadequate.

Summary: This review aims to explore the pathophysiological manifestations of MASLD, the mechanisms through which hypoxia-inducible factor-1α (HIF-1α) contributes to disease progression, and the potential therapeutic approaches targeting HIF-1α, offering feasible strategies for treating advanced MASLD.

Key message: Studies suggest that hepatocytes in MASLD are often in a hypoxic state, which activates HIF-1α, playing a crucial role in disease progression. During hypoxia, the expression of HIF-1α increases throughout the different stages of MASLD, interacting with various genes and pathways, influencing lipid metabolism, steatosis, and fibrosis progression.

Introduction: Colorectal serrated adenocarcinoma (SAC), a subtype of colorectal adenocarcinoma determined histologically, has characteristics of epithelial serrations. Here, we examined the immunohistochemical and clinicopathological characteristics of colorectal SAC.

Methods: Thirty-three specimens, pathologically diagnosed as SAC in our hospital between 2013 and 2022, were collected for immunohistochemistry of MLH1/MUC2/MUC5AC/p53 and sequencing of BRAF/KRAS mutations.

Results: The proximal colon contained 25 lesions and the distal colon had 8. Patients with proximal SACs were predominantly female, whereas those exhibiting distal SACs were predominantly male (p = 0.003). Overall, lymph node and distant metastasis were present in 17 (52%) and 11 (33%) cases, respectively, with no significant differences between the proximal and distal groups. MLH1 expression loss was more frequent in proximal cases (40%) than distal SACs (13%). Most cases (97%) were MUC2+. MUC5AC+ was significantly more frequent in proximal cases (92%) than distal SACs (37%, p = 0.004). Significantly less p53 overexpression was present in proximal cases (40%) vs. distal SACs (75%). Genetically, the 12 cases of SAC harboring BRAF mutations were all located in the proximal colon, with a significantly greater frequency (p = 0.030), whereas more frequent KRAS mutations were noted in distal SACs. Throughout 5 years of follow-up, 3 patients (2 proximal SAC cases; 1 distal SAC case) died (mean 6.7 months after surgery) because of their disease.

Conclusion: Proximal SACs exhibit distinct clinicopathological and molecular features compared to distal SACs, largely aligning with the sessile serrated and traditional serrated pathways, respectively.