Obscure gastrointestinal bleeding (OGIB) accounts for approximately 5% of all gastrointestinal bleeding cases, with the small intestine being the most common source of origin. Primary small-bowel lymphoma is a rare malignancy that can present as intestinal bleeding in 2% to 22% of cases. A 67-year-old male presented with a four-day history of diarrhea and melena, accompanied by severe anemia with a hemoglobin level of 5 g/dL. While a colonoscopy only revealed internal hemorrhoids and an ascending colon polyp, a subsequent non-contrast whole-abdomen CT scan demonstrated a 6-cm segmental small bowel wall thickening involving the proximal and distal ileum, accompanied by mesenteric fat stranding and aggressive aneurysmal dilatation. Further evaluation using antegrade enteroscopy identified a mass with central ulceration in the proximal ileum. Histopathological analysis of the ileal biopsy specimens revealed small intestinal mucosa heavily infiltrated by a diffuse, highly cellular tumor with small-to-medium neoplastic cells, confirming a malignant round cell neoplasm highly suspicious for non-Hodgkin lymphoma. This case highlights the critical clinical challenge of managing OGIB and underscores the importance of early diagnostic interventions. Utilizing CT imaging alongside device-assisted enteroscopy is vital for the prompt recognition of hidden small bowel disorders like lymphoma, enabling timely treatment, preventing life-threatening hemorrhagic complications, and improving the overall patient prognosis.

Peutz-Jeghers syndrome (PJS) is a rare autosomal dominant hamartomatous polyposis disorder characterised by mucocutaneous pigmentation and multiple gastrointestinal polyps, most commonly involving the small intestine. Paediatric patients frequently present with complications, such as abdominal pain, gastrointestinal bleeding, and recurrent intussusception. We report the case of a nine-year-old female with classical clinical and radiological features of PJS, including multisite gastrointestinal polyposis and a prior history of intussusception. Contrast-enhanced computed tomography revealed multiple heterogeneously enhancing sessile polyps involving the stomach, duodenum, colon, and rectum. Histopathological examination confirmed the diagnosis of PJS. In addition, imaging demonstrated incidental findings of femoral head epiphyseal flattening and sclerosis, consistent with avascular necrosis, suggestive of Legg-Calvé-Perthes disease (LCPD). A comprehensive review of the available literature revealed no previously reported cases describing a similar radiological association between PJS and LCPD. While both conditions are individually well documented, their coexistence appears to be extremely rare, thereby highlighting the novelty of the present case. The patient was managed conservatively and is currently under follow-up, with a stable clinical status. This case underscores the value of comprehensive cross-sectional imaging in pediatric patients with syndromic disorders, facilitating both diagnostic confirmation and the identification of unexpected but clinically significant incidental findings.

Colorectal serrated polyps are now recognized as an important pathway in colorectal carcinogenesis. An association between serrated polyposis syndrome (SPS) and duodenal serrated lesions sharing a similar immunophenotype in both the colon and duodenum has been reported in the literature. We present a case of a 38-year-old male who presented in June 2023 with abdominal pain and fever. Initial investigations, including multiple computed tomography scans of the abdomen and pelvis, revealed an appendiceal abscess and small bowel intussusception involving two segments of the jejunum without evidence of obstruction, along with multiple polyps throughout the small and large bowel suggestive of an intestinal polyposis syndrome. Further evaluation with colonoscopy, esophagogastroduodenoscopy, and magnetic resonance enterography confirmed the presence of numerous polyps of varying sizes involving the duodenum, jejunum, ileum, and all segments of the colon. The initial differential diagnosis included familial adenomatous polyposis, Peutz-Jeghers syndrome, and PTEN hamartoma tumor syndrome. The patient subsequently developed complicated small bowel obstruction due to intussusception and underwent open small bowel resection. Multiple intestinal polyps were identified, and histopathological examination confirmed the diagnosis of SPS. At a later stage, the patient was planned for subtotal colectomy, preceded by elective endoscopic polypectomy, which achieved clearance of the left colon up to 20 cm from the anal verge. Gross examination of the colectomy specimen revealed more than 20 large polyps measuring up to 4 cm. Histopathological analysis demonstrated colonic serrated polyposis without evidence of invasive malignancy, wall infiltration, or lymph node involvement, with clear surgical margins.

Esophageal cancer is a highly aggressive malignancy of the digestive tract, with surgical resection remaining the cornerstone of curative treatment. For patients with an intact stomach, reconstruction using a gastric conduit via gastric pull-up is the preferred approach following esophagectomy. However, in cases where the stomach is unavailable—due to prior gastric surgery, polyps, or concurrent tumors—alternative conduits must be considered. By reviewing relevant domestic and international research literature, this review evaluates the indications, benefits, limitations, and common complications associated with jejunal, colonic, and ileocolonic interpositions. Additionally, strategies for the prevention and management of complications are discussed. By synthesizing the latest clinical evidence, we aim to provide practical recommendations to guide surgical decision-making and improve outcomes in the management of esophageal cancer. The jejunum, colon, and ileocolon represent the primary options for esophageal reconstruction, each offering unique anatomical and functional advantages as well as distinct technical challenges and complication profiles.

Endoscopic procedures play a central role in the diagnosis and management of gastrointestinal (GI) diseases, yet the field lacks large-scale, clinically diverse benchmarks and unified datasets to evaluate vision foundation models. We introduce PanEndoSuite, the first unified ecosystem for endoscopic AI, developed through systematic collaboration between AI researchers and practicing gastroenterologists. PanEndoSuite consists of three complementary components: PanEndoAtlas, PanEndoX, and PanEndoFM. PanEndoAtlas is a harmonized dataset of over 420,000 labeled images from 30 public endoscopy datasets across 13 countries and 26 hospitals, creating a clinically-grounded hierarchical taxonomy that mirrors diagnostic reasoning patterns across 111 GI diseases. PanEndoX is a benchmark of 10 clinically grounded tasks, including hierarchical GI-tree classification, Barrett's esophagus grading, ulcerative colitis scoring, polyp subtyping, Boston Bowel Preparation Scale assessment, multi-organ disease classification, and anatomical landmark identification-designed to probe generalization across anatomical regions, disease presentations, and annotation granularities. PanEndoFM is a foundation model pretrained on a 10 million-image corpus curated from public data sources, spanning the entire GI tract. We benchmark PanEndoFM against two endoscopy-specific foundation models (EndoFM-LV, EndoSSL) and two general-purpose vision models (ViT-B/16, ResNet-50). PanEndoFM achieves the highest macro-AUC on 6 of 10 tasks, demonstrating broad clinical generalization; EndoFM-LV performs best on colon-focused tasks, EndoSSL excels in polyp subtyping, and ViT-B/16 shows strengths on small-intestine conditions. Together, PanEndoSuite establishes a foundation for building robust, generalist AI systems in gastrointestinal endoscopy that bridge current AI capabilities and clinical practice.

Cystic fibrosis (CF) alters gut physiology, yet its impact on microbial communities across colonic regions (ascending, transverse, descending colon) and microhabitats (lumen, mucosa) remains incompletely understood. Here, we applied culturomics to characterize gut microbiota in a small cohort of 32 individuals (22 non-CF, 10 CF). Persons with CF (pwCF) exhibited significantly higher viable bacterial loads than non-CF individuals, particularly in mucosal samples. Anaerobes predominated overall, with relative enrichment of aerobes in the mucosa of pwCF. Alpha diversity was reduced in mucosal samples and aerobic cultures for pwCF, whereas beta diversity was influenced by all the tested variables except the colonic region. Phylum-level analyses revealed enrichment of Proteobacteria and depletion of Actinobacteria, Bacteroidota, and Firmicutes in samples from pwCF, consistent with stool analysis. Random forest models identified selected oral-associated microbes as key predictive taxa and accurately classified polyp status within this cohort. Whole-genome sequencing of Bacteroides fragilis (n = 21) and Escherichia coli (n = 15) isolates, representing a subset of 109 gut bacterial genomes sequenced from this cohort, revealed minimal genomic variation across colonic regions and sample types, indicating intra-individual strain stability. The understandings from this pilot culturome study, after future validation, may help in developing targeted microbial therapeutic approaches to address the gut dysbiosis of CF.

Natural polyamines, such as spermidine and spermine, exert strong anti-inflammatory effects, but their therapeutic benefits are limited by rapid absorption in the small intestine, resulting in low colonic availability. In this study, engineered Citrobacter freundii overexpressing ppk1 (CPP) could significantly enhance both intracellular polyamine synthesis and polyphosphates (PolyP) accumulation. Under a two-step cultivation process, the engineered strain produced substantial amounts of polyamines, including spermidine (145.14 ± 5.11 mg/g) and spermine (175.31 ± 4.2 mg/g). CPP responds to environmental stress by importing large amounts of phosphate for PolyP synthesis. This process further promotes polyamine production, which binds to PolyP to neutralize intracellular charge. The resulting polyamine-polyphosphate granules (PPGs) enhance both binding stability and slow-release properties in vivo. Notably, the oral administration of PPGs increased colonic polyamine levels, alleviated DSS-induced colitis, reduced inflammatory cytokines, and restored gut microbiota balance. Overall, biosynthesized PPGs represent a highly promising material for mitigating colitis.

BACKGROUND Filiform polyposis (FP) is a rare pseudopolyp associated with inflammatory bowel disease (IBD), characterized by elongated mucosal projections. It is found primarily in the colon and rectum, and presentation in the ileum is rare. Despite its benign nature, FP can mask underlying chronic intestinal inflammation. CASE REPORT A 52-year-old woman presented with loose stool but no other gastrointestinal symptoms. She was found to have a branched mucosal mass in the terminal ileum and diffuse ulcerations throughout the colorectum. Initial laboratory tests indicated anemia and elevated inflammatory markers. After 3 months of treatment with mesalazine and adjuvant drugs, the symptom of loose stool had improved, but the colonoscopy and imaging examination results show little change from the initial visit. Colonoscopy, imaging, and histopathology supported a diagnosis of Crohn's disease (CD). The ileal mass was identified as filiform polyposis. After multidisciplinary consultation, she was treated with Ustekinumab, leading to significant symptomatic and endoscopic improvement. The mass was subsequently resected via hybrid ESD and confirmed as an inflammatory polyp. CONCLUSIONS This case reveals that although a patient has no significant symptoms related to CD, FP located at the terminal ileum can initially manifest as CD, highlighting the need for through evaluation to detect underlying IBD. Multidisciplinary collaboration is essential for accurate diagnosis and management. FP can be the "tip of the iceberg" in hidden chronic intestinal inflammation, necessitating careful endoscopic and histologic assessment.

Background and Clinical significance: Cowden syndrome is an autosomal dominant disorder caused by germline loss-of-function mutations in the PTEN tumor suppressor gene. It is characterized by multiple hamartomas and an increased lifetime risk of malignancies affecting the breast, thyroid, endometrium, and gastrointestinal (GI) tract. Pediatric presentations may include macrocephaly, scrotal tongue, and intellectual disability. Gastrointestinal involvement is frequent, with juvenile-like hamartomatous polyps occurring in at least half of patients and distributed throughout the GI tract, posing a risk for malignant transformation. Early diagnosis and surveillance are crucial for improving patient outcomes. Case Presentation: We report a case of a 10-year-old Caucasian female with Cowden syndrome, with a history of a malignant germ cell tumor of the ovary consisting of a yolk sac tumor and low-grade immature teratoma diagnosed at age six, and thyroidectomy at age nine. The patient has mild intellectual disability. Routine radiological surveillance revealed a right colon intraluminal mass, prompting referral for pediatric gastroenterology evaluation. Endoscopy identified multiple polyps throughout the colon, stomach, and small intestine. Polypectomy of larger lesions was performed, and histopathology confirmed juvenile-like hamartomatous polyps without dysplasia or malignancy. This case highlights the necessity of comprehensive gastrointestinal evaluation in pediatric Cowden syndrome patients. Endoscopic surveillance is essential for early detection and management of polyps. Conclusions: Given the multisystem involvement and elevated cancer risk associated with PTEN mutations, a multidisciplinary approach that includes genetic counseling, dermatologic evaluation, and ongoing oncologic monitoring is recommended. Increased awareness of gastrointestinal manifestations enables timely intervention and may reduce morbidity and mortality in this high-risk population.

While juvenile hamartomatous polyps are common pediatric findings, they are almost exclusively restricted to the colon and rectum; their occurrence in the small intestine is exceptionally rare and presents a significant diagnostic dilemma. This case report describes an eight-year-old patient who presented with vague constitutional symptoms, including intermittent vomiting, abdominal pain, and severe weight loss resulting in a Z-score of -3.29. Initial diagnostic investigations, including abdominal ultrasound, computed tomography, upper digestive endoscopy, and contrast bowel studies, failed to identify a clear etiology. Following an exploratory laparotomy, a juvenile hamartomatous polyp was identified in the mid-jejunum, acting as a lead point for intermittent intussusception with secondary vascular congestion of the intestinal loops. The diagnosis was confirmed through anatomopathological analysis after a successful enterectomy. This case demonstrates that in the presence of unexplained malnutrition and cyclical emesis, clinicians must maintain a high index of suspicion for small bowel lesions, as prompt surgical intervention can prevent further complications and lead to complete symptomatic resolution.

An 88-year-old female was admitted with a complaint of melena. Abdominal computed tomography revealed a dense mass and a target sign in the distal ileum, suggesting an intestinal mass and associated intussusception. However, there were no signs of intestinal obstruction or ischemic change. Retrograde single-balloon enteroscopy revealed a lesion in the distal ileum that appeared as a spherical mass in the frontal view, with a long stalk visible posteriorly. Detailed observation was challenging. At that time, intussusception was not observed. Contrast examination revealed a long and slender mass with a hemispherical, dome-shaped head. As the source of bleeding remained unidentified, enteroscopic clipping and tattooing were performed for preoperative marking. Given the patient's stable hemodynamic and respiratory status, single-incision laparoscopic surgery was performed one week later. Intraoperatively, the tattooed section of the ileum, demonstrating evidence of intussusception, was easily identified. The affected segment was exteriorized through the single-incision port, and the intussusception was relieved using the Hutchinson maneuver. Approximately 20cm of the ileum, including the tattooed segment, was resected, followed by reconstruction using a functional end-to-end anastomosis. Gross examination of the resected specimen revealed a 20×90mm polyp with a slender, "worm-like" appearance-typical of an enteric muco-submucosal elongated polyp (EMSEP). Histopathological analysis confirmed the presence of normal mucosa and submucosa with a variably prominent mixture of blood and lymphatic vessels. Although EMSEPs are frequently observed in the colon, they are exceedingly rare in the small intestine. Their detection during routine health screenings is challenging due to their location, and they often manifest as intussusception. Because endoscopic management of small EMSEPs can be challenging, lesion tattooing followed by laparoscopic surgery is a good treatment choice.