Introduction

Cholangiocarcinoma (CCa) is a complex neoplasm with poor prognosis, classified as intrahepatic (iCCa), perihilar (pCCa), or distal (dCCa) in the bile duct. Its variable phenotypes pose diagnostic challenges. Digital single-operator cholangioscopy (DSOC) aids diagnosis but has limitations, including suboptimal biopsy sensitivity, lack of a standardized morphology classification, as well as technical issues. Emerging evidence highlights AI’s potential to enhance DSOC diagnostic capacity, but the differential performance according to tumor characteristics, namely its topography, remains unassessed.

Aims & Methods

This study aimed to evaluate an AI algorithm’s effectiveness in detecting iCCa, pCCa, and dCCa. A deep learning model based on a convolutional neural network (CNN) was designed to automatically predict the malignancy status of biliary strictures. The model was built using DSOC images from four international high-volume centers: Centro Hospitalar Universitário de São João (Porto, Portugal), Hospital Universitario Puerta de Hierro Majadahonda (Madrid, Spain), New York University Langone Hospital (New York, USA) and University of Chicago Medicine (Chicago, USA). Images showing strictures due to cholangiocarcinoma or benign conditions were included. The model was trained with a learning rate of 0.0001, a batch size of 32, and a number of epochs of 10, using PyTorch framework. The detection rate of the algorithm was compared for each location category.

Results

A total of 18166 images from 32 patients from 4 centers. A total of 22 patients were male (69%) and the mean age was 63 years (SD: 11 years). Common bile duct (CBD) strictures represented 44% of the total (n=14) while intrahepatic and perihilar accounted for 22% (n=7) and 34% (n=11), respectively. The algorithm’s DR of strictures representing CCa was 91.6% for iCCa, 89.4% for pCCa and 92.4% for dCCa. Pairwise comparisons revealed a significant difference in the DR for iCCa and pCCa (p<0.05) and dCCa and pCCa (p<0.001).

Conclusion

Topographic characteristics of biliary strictures influence the diagnostic performance of DSOC. While AI shows promise in improving the diagnostic capacity of DSOC, its performance is impacted by DSOC technical limitations. To our knowledge, this is the first multicentric and transatlantic algorithm, capable of providing detection and differentiation of morphologic features of biliary strictures. Developing models should address and control for these issues before widespread clinical integration. Additionally, this evidence stresses the importance of keeping a “human on the loop”, providing clinical reasoning to guide the application of AI algorithms.

Introduction

Hepatocellular carcinoma (HCC) is characterized by high invasiveness and metastatic potential, with persistently low five-year survival rates. While vitamin D has demonstrated anti-tumor effects in various cancers, its precise molecular mechanism in HCC remains unclear. This study aimed to investigate the inhibitory role of vitamin D in HCC progression, focusing on the regulatory function of acetyl-CoA acetyltransferase 2 (ACAT2).

Aims & Methods

Huh-7 cells were treated with increasing concentrations of vitamin D (0, 15, 20, 30, and 40 nM) for 48 hours. Cell migration was assessed using Transwell assays, and apoptosis was quantified via Annexin V/PI staining followed by flow cytometry. ACAT2 mRNA and protein levels were measured by qPCR and Western blot, respectively. Prognostic relevance of ACAT2 expression was analyzed using Kaplan–Meier survival curves based on the GSE76427 dataset. Mechanistically, single-cell transcriptomic data from 26 HCC patients were integrated to identify ACAT2⁺ malignant cell populations and their enriched pathways via KEGG analysis. Mendelian randomization (MR) using the inverse-variance weighted (IVW) method was employed to assess the causal relationship between genetically predicted vitamin D levels and HCC risk, and to quantify the mediation effect of ACAT2.

Results

Vitamin D treatment significantly suppressed Huh-7 cell migration and induced apoptosis in a dose-dependent manner. ACAT2 expression was consistently downregulated at both mRNA and protein levels. Clinical analysis revealed that high ACAT2 expression was associated with poor prognosis in HCC patients. Single-cell analysis showed that ACAT2 expression was markedly elevated in tumor hepatocytes, and ACAT2⁺ cells were enriched in cytochrome P450-related xenobiotic metabolism pathways. MR analysis demonstrated a significant inverse association between genetically predicted vitamin D levels and HCC risk, and ACAT2 was identified as a significant mediator, accounting for 9.6%.

Conclusion

This study provides novel evidence that vitamin D suppresses HCC progression by downregulating ACAT2. ACAT2 may serve as a potential prognostic biomarker and therapeutic target. These findings support the translational potential of vitamin D as an adjunctive strategy in HCC prevention and treatment.

Introduction

Inflammatory bowel disease (IBD) is associated with an increased risk of cerebrovascular disease (CVD) and coronary heart disease (CHD). It has been suggested that chronic inflammation may be the mechanism. Previous studies have primarily assessed IBD as a group and not ulcerative colitis (UC) or Crohn’s disease (CD) separately.

Aims & Methods

This study aims to determine the relationship between UC and CD and CVD and CHD risk factors/outcomes in a large UK population. General practice electronic medical records were sourced from the United Kingdom (UK) via The Health Improvement Network (THIN). UC and CD risk factors and disease outcomes were identified through Read codes.

Results

Factors	UC Prevalence, n (%) n=3,432	UC Odds Ratio, 95% CI	CD Prevalence, n (%) n=2,831	CD Odds Ratio, 95% CI
Female Sex	1,796 (52.3%)	1.16, 1.09-1.25	1,689 (59.7%)	2.71, 2.08-3.62
Age	43.95 ± 14.4	0.99, 0.99-0.99	45.7 ± 15.7	0.95, 0.94-0.96
Diabetes Type II	417 (12.2%)	1.50, 1.35-1.66	265 (9.4%)	1.12, 0.98-1.27
Dyslipidemia	176 (5.1%)	1.26, 1.08-1.47	112 (4.0%)	0.96, 0.79-1.16
Obesity	7 (0.2%)	0.99, 0.47-2.10	7 (0.3%)	1.21, 0.58-2.55
AMI	113 (3.3%)	1.57, 1.30-1.89	57 (2.0%)	0.95, 0.73-1.23
Ischemic Stroke	47 (1.4%)	1.46, 1.09-1.95	23 (0.8%)	0.86, 0.57-1.30
Intracranial Hemorrhage	15 (0.4%)	1.67, 1.01-2.78	10 (0.4%)	1.35, 0.72-2.51
COPD	31 (0.9%)	1.85, 1.30-2.64	24 (0.9%)	1.74, 1.16-2.59

A total of 1,062,022 unique adult patients were available for analysis. There were 3,432 UC (mean age: 43.95 years, SD=14.4 years; 52% female) and 2,831 CD cases (mean age: 40.9 years, SD=14.06 years; 60% female).

Ulcerative Colitis: Univariate analysis in Table 1. Multiple logistic regression (MLR) of CHD risk factors and outcomes (adjusted in all models for age, sex, diabetes, COPD, dyslipidaemia, obesity, and statins) revealed statistically significant independent CHD risk factors: female sex (OR: 1.19, 95%CI: 1.11-1.28), younger age (OR: 0.98, 95%CI: 0.98-0.99), type 2 diabetes (OR: 1.22, 95%CI: 1.09-1.37), and increased risk of acute myocardial infarction (AMI) (OR: 1.35, 95%CI: 1.11-1.64).
MLR of CVD risk factors and outcomes (adjusted as above plus thrombolytic agents) found statistically significant independent CVD risk factors: female sex (OR: 1.19, 95%CI: 1.10-1.27), younger age (OR: 0.99, 95%CI: 0.98-0.99), diabetes type 2 (OR: 1.20, 95%CI: 1.07-1.34), statin use (OR: 1.13, 95%CI: 1.03-1.25), and any anti-thrombolytic agents (OR: 1.37, 95%CI: 1.25-1.51).
Crohn’s Disease: Univariate analysis in Table 1. MLR of CHD risk factors and outcomes (adjusted) revealed statistically significant independent CHD risk factors: female sex (OR: 0.92, 95%CI: 0.85-0.99), younger age (OR: 0.98, 95%CI: 0.97-0.99), statin use (OR: 1.23, 95%CI: 1.11-1.36), and an increased likelihood of death (OR: 1.28, 95%CI: 1.12-1.47).
MLR of CVD risk factors and outcomes (adjusted) revealed statistically significant independent CVD risk factors: female sex (OR: 0.91, 95%CI: 0.84-0.98), younger age (OR: 0.97, 95%CI: 0.96-0.98), anti-thrombolytic agents (OR: 1.71, 95%CI: 1.55-1.90), and an increased likelihood of death (OR: 1.18, 95%CI: 1.03-1.35).

Conclusion

UC cases are more likely to be female, have diabetes, be taking statins, and anti-thrombolytic agents, and have an increased risk of AMI and death. CD cases are less likely to be female, but more likely to be taking statins, anti-thrombolytic agents, and more likely to die.

Disclosure

Guy D. Eslick and Michael P. Jones have nothing to disclose. Nicholas J. Talley Disclosures: GutSee Ltd (consulting microbiome, 2025), Brown University, Agency for Health Care Research and Quality (fiber and laxation) (2024), Rome Foundation (member gastroduodenal committee) (present) Biocodex (FD diagnostic tool) (present) Microba (consulting microbiome - commencing 2025) Comvita Manuka Honey (FD trial consulting) (2025), BluMaiden outside the submitted work. In addition, Dr. Talley has a patent Nepean Dyspepsia Index (NDI) 1998, a patent Licensing Questionnaires Talley Bowel Disease Questionnaire licensed to Mayo/Talley, “Diagnostic marker for functional gastrointestinal disorders” Australian Provisional Patent Application 2021901692, ”Methods and compositions for treating age-related neurodegenerative disease associated with dysbiosis” US Patent Application No. 63/537,725.
Boards: The Gut Foundation Board (2025-present), Asia Pacific Association of Medical Editors (APAME) Board (President 2023-2025), Doctors for the Environment (Chair 2024-present), Luminal Faculty GESA (Chair) (2023-2025)
Editorial: UptoDate (Section Editor), Mayo Clinic Proceeding Associate Editor (2023-present)
Financial support: Dr. Talley is supported by funding from the National Health and Medical Research Council (NHMRC) to the Centre for Research Excellence in Digestive Health and he holds an NHMRC Investigator grant.

Introduction

Active ulcerative colitis (UC) is typically assessed through clinical manifestations, laboratory examinations, and colonoscopy, which also determine the disease's severity.
An easy-to-use and patient-friendly technique for early clinical suspicion confirmation is intestinal ultrasonography (IUS). Ancillary technologies such as elastographic techniques have recently become available and can be used in conjunction with traditional IUS.

Aims & Methods

The study aim was to assess the accuracy and reproducibility of intestinal 2D-shear Wave Elastography (2D-SWE) as a predictor of disease’s activity and mucosal healing (MH). 2D-SWE was performed in 34 consecutive patients with active disease confirmed by colonoscopy. The 2D-SWE measurements (n. 10 with IQR/Med < 30%) was taken in the sigmoid colon by two independent operators at basal and 3 months after the starting of a new treatment regimen. The correlation between 2D-SWE and the Mayo endoscopic score (MES) was investigated along with clinical and conventional ultrasound parameters such as Bowel Wall Thickness (BWT) and Limberg score (LS).

Results

2D-SWE values (kPa) positively correlated with MES with a statistically significant difference between mucosal healing (MH) and active disease groups (p = 0.003). The AUROC (95% CI) for assessing mucosal healing by 2D-SWE was 0.84 (95% CI: 0.70-0.97). Using a cut off value of 21.5 kPa, sensibility and the specificity for mucosal healing were 0.62 and 0.99, respectively. The median 2D-SWE values obtained by the two independent operators were 19.7 kPa (IQR 16.2-26.8) and 17.7 kPa (IQR 14.4-23.7) respectively. 2D-SWE was also positively correlated with rectal bleeding, LS and BWT (r 0.38 p=0.027; r 0.43 p=0.014; r 0.33 p=0.057) but not with fecal calprotectin and C-reactive protein. No significant correlation was found between 2D-SWE values and clinical remission (Partial Mayo Score ≤ 2) after 3 months of a new treatment regimen (p = 0.491).

Conclusion

This study demonstrated the feasibility of 2D-SWE technique with an excellent inter-observer repeatability. The technique showed good accuracy in predicting mucosal healing, with increasing values correlating with disease severity. In the future, 2D-SWE could help reduce the number of colonoscopies and improve clinical decision making.

Disclosure

No discosure to declare

Clinical Case Summary

A 24-year-old male presented with jaundice and mild vertigo after a 10-day prodrome (asthenia, nausea, headache, fever). Ibuprofen (1200 mg/d) was taken for these symptoms only during the first 5 days. Labs revealed acute hepatocellular injury and elevated cholestasis (AST 215, ALT 862, FA 134, GGT 126 IU/L), marked mixed hyperbilirubinemia (Total 13.5 mg/dL, Direct 7.58 mg/dL) and coagulopathy (INR 1.59). Ultrasound showed hepatosplenomegaly. Viral hepatitis (HAV/HBV/HCV/CMV) and autoimmune/metabolic causes were excluded. Epstein-Barr Virus (EBV) serology showed low-titer positive VCA IgM but negative VCA IgG, EBNA IgG, and serum EBV DNA PCR, indicating recent non-active infection. Given ibuprofen timing and high RUCAM score, drug-induced liver injury (DILI) with a hepatocellular pattern was suspected. Liver biopsy confirmed acute hepatitis with lymphomonocytic infiltrate, necrosis and canalicular cholestasis. Despite improving liver function tests post-ibuprofen cessation, he developed worsening vertigo, severe ataxia, nausea, vomiting, hypophonia, necessitating nasogastric feeding/bed confinement. Cerebrospinal fluid (CSF) showed mild mononuclear pleocytosis (16 cells/mm³); a multiplex PCR pathogen panel (including EBV) was negative. Brain MRI/EEG were normal. Post-infectious EBV acute cerebellar ataxia was diagnosed concurrently with DILI, based on timing post-recent EBV, exclusion of active neurological infection (negative CSF PCR, normal imaging), mild pleocytosis, and supported by later IgG seroconversion. IV methylprednisolone treatment, chosen for clinical severity, led to significant neurological improvement within days and eventual recovery after physiotherapy. This case highlights the significant challenges of diagnosis and management of concomitant DILI and recent EBV infection with neurological sequelae, requiring careful differentiation of liver damage patterns (hepatocellular DILI vs cholestatic EBV) and optimal management of neurological symptoms.

References

Illustrative Material References:
- Liver biopsy histology slides (highlighting lymphomonocytic infiltrate, necrosis, and canalicular cholestasis characteristic of DILI).
- Table/Graph showing serial Liver Function Tests (AST, ALT, Bilirubin) over time, depicting injury peak and recovery trend.
- Table summarizing sequential Epstein-Barr Virus (EBV) serology results (VCA IgM, VCA IgG, EBNA IgG) demonstrating seroconversion.
- Table summarizing Cerebrospinal fluid (CSF) analysis results (cell count, protein, glucose, negative multiplex PCR).
- Representative Brain MRI images (axial/sagittal views) confirming absence of structural lesions or encephalitis signs.