CRIg+ macrophages deficiency enhanced inflammation damage in IBD due to gut extracellular vesicles containing microbial DNA.

Gut microbiota-derived extracellular vesicles (mEVs) are reported to regulate inflammatory response by delivering bacterial products into host cells. The complement receptor of the immunoglobulin superfamily macrophages (CRIg+ Mφ) could clear invading bacteria and their derivatives. Here, we investigate the role of CRIg+ Mφ and the mechanism by which mEVs regulate intestinal inflammation. We found that it is exacerbated in IBD patients and colitis mice by mEVs' leakage from disturbed gut microbiota, enriching microbial DNA in the intestinal mucosa. CRIg+ Mφ significantly decrease in IBD patients, allowing the spread of mEVs into the mucosa. The microbial DNA within mEVs is the key trigger for inflammation and barrier function damage. The cGAS/STING pathway is crucial in mEVs-mediated inflammatory injury. Blocking cGAS/STING signaling effectively alleviates inflammation caused by mEVs leakage and CRIg+ Mφ deficiency. Microbial DNA-containing mEVs, along with CRIg+ Mφ deficiency, stimulate inflammation in IBD, with the cGAS/STING pathway playing a crucial role.

Over-the-scope clip as a rescue treatment for massive bleeding due to Dieulafoy lesion at the colorectal anastomosis: A case report.

RATIONALE: The bleeding of Dieulafoy lesion predominantly involves the proximal stomach and leads to severe gastrointestinal bleeding. However, these lesions have also been reported in the whole gastrointestinal tract. Bleeding of Dieulafoy lesions at the anastomosis was seldomly reported and was very easy to be ignored clinically. PATIENT CONCERNS: We describe a 72-year-old woman with a past history of surgery for rectal carcinoma hospitalized with chief complaint of massive rectal bleeding. No gross bleeding lesion was found during the first emergency colonoscopy. Despite multiple blood transfusions, her hemoglobin rapidly dropped to 5.8 g/dL. DIAGNOSIS: She was diagnosed with Dieulafoy lesion at the colorectal anastomosis during the second emergency colonoscopy. INTERVENTIONS: Primary hemostasis was achieved by endoscopic hemostatic clipping. However, she experienced another large volume hematochezia 3 days later, and then received another endoscopic hemostatic clipping. She was improved and discharged. However, this patient underwent hematochezia again 1 month later. Bleeding was arrested successfully after the over-the-scope clip (OTSC) was placed during the fourth emergency colonoscopy. OUTCOMES: This patient underwent 4 endoscopic examinations and treatments during 2 hospitalizations. The lesion was overlooked during the first emergency colonoscopy. The second and third endoscopes revealed Dieulafoy lesion at the colorectal anastomosis and performed endoscopic hemostatic clippings, but delayed rebleeding occurred. The bleeding was stopped after the fourth emergency colonoscopy using OTSC. There was no further rebleeding during hospitalization and after 2-year of follow-up. LESSONS: As far as we know, there is no reported case of lower gastrointestinal bleeding caused by Dieulafoy lesion at the colorectal anastomosis, OTSC is a safe and effective rescue treatment for Dieulafoy lesions.

Development and validation of a three-dimensional deep learning-based system for assessing bowel preparation on colonoscopy video.

Background: The performance of existing image-based training models in evaluating bowel preparation on colonoscopy videos was relatively low, and only a few models used external data to prove their generalization. Therefore, this study attempted to develop a more precise and stable AI system for assessing bowel preparation of colonoscopy video. Methods: We proposed a system named ViENDO to assess the bowel preparation quality, including two CNNs. First, Information-Net was used to identify and filter out colonoscopy video frames unsuitable for Boston bowel preparation scale (BBPS) scoring. Second, BBPS-Net was trained and tested with 5,566 suitable short video clips through three-dimensional (3D) convolutional neural network (CNN) technology to detect BBPS-based insufficient bowel preparation. Then, ViENDO was applied to complete withdrawal colonoscopy videos from multiple centers to predict BBPS segment scores in clinical settings. We also conducted a human-machine contest to compare its performance with endoscopists. Results: In video clips, BBPS-Net for determining inadequate bowel preparation generated an area under the curve of up to 0.98 and accuracy of 95.2%. When applied to full-length withdrawal colonoscopy videos, ViENDO assessed bowel cleanliness with an accuracy of 93.8% in the internal test set and 91.7% in the external dataset. The human-machine contest demonstrated that the accuracy of ViENDO was slightly superior compared to most endoscopists, though no statistical significance was found. Conclusion: The 3D-CNN-based AI model showed good performance in evaluating full-length bowel preparation on colonoscopy video. It has the potential as a substitute for endoscopists to provide BBPS-based assessments during daily clinical practice.