Publications by authors named "Roser Vega"

Background And Aims: Inflammatory bowel disease [IBD] is associated with high rates of post-colonoscopy colorectal cancer [PCCRC], but further in-depth qualitative analyses are required to determine whether they result from inadequate surveillance or aggressive IBD cancer evolution.

Methods: All IBD patients who had a colorectal cancer [CRC] diagnosed between January 2015 and July 2019 and a recent [<4 years] surveillance colonoscopy at one of four English hospital trusts underwent root cause analyses as recommended by the World Endoscopy Organisation to identify plausible PCCRC causative factors.

Results: In total, 61% [n = 22/36] of the included IBD CRCs were PCCRCs.

View Article and Find Full Text PDF

Background: Ustekinumab was approved in 2016 for the treatment of moderate-severe Crohn's disease (CD). Clinical trials and real-world studies have suggested ustekinumab to be a safe and effective treatment; however, studies to date infrequently use imaging techniques to predict response to biologics in CD.

Objectives: We assessed the 2-year real-world effectiveness and safety of ustekinumab in a tertiary CD cohort with the use of novel imaging techniques.

View Article and Find Full Text PDF

Background And Aim: Lack of visual recognition of colorectal polyps may lead to interval cancers. The mechanisms contributing to perceptual variation, particularly for subtle and advanced colorectal neoplasia, have scarcely been investigated. We aimed to evaluate visual recognition errors and provide novel mechanistic insights.

View Article and Find Full Text PDF
Article Synopsis
  • A convolutional neural network (CNN) was developed to classify polyps as adenomatous or nonadenomatous using video data from narrow-band imaging (NBI) and NBI-near focus (NBI-NF), including sessile serrated lesions (SSLs).
  • The CNN was trained on 16,832 frames from 229 polyp videos and tested with 222 polyp videos, demonstrating high sensitivity (around 89-92%) and specificity (around 88-94%) for identifying adenomas and diminutive polyps across various test sets.
  • The results showed that the CNN outperformed nonexpert endoscopists in accuracy while performing comparably to experts, highlighting its potential in enhancing computer-a
View Article and Find Full Text PDF
Article Synopsis
  • Crohn's disease (CD) is a chronic inflammatory condition affecting the intestines that can lead to serious complications if not treated early; the study aims to identify which newly diagnosed patients may develop severe forms of the disease.
  • The research involves a multicentre, non-randomised study of newly diagnosed adult CD patients, utilizing data from the METRIC study and additional participants to assess the effectiveness of various magnetic resonance enterography (MRE) scores in predicting disabling CD outcomes within five years.
  • Ethical approval has been obtained for the study, and results will be shared through conferences and peer-reviewed articles to inform medical practices.
View Article and Find Full Text PDF
Article Synopsis
  • The study examines the effectiveness of sequential drug treatments for ulcerative colitis (UC), specifically comparing the use of vedolizumab (VDZ) and anti-TNF therapies as second-line treatments.
  • Researchers analyzed data from patients who switched treatments between May 2013 and August 2020, looking at various health outcomes over a 52-week period.
  • Results indicated that patients receiving VDZ after anti-TNF had significantly better treatment persistence, colectomy-free survival, and clinical remission compared to those receiving anti-TNF after VDZ, suggesting a favorable effect of the treatment order on patient outcomes.
View Article and Find Full Text PDF

Objectives: There is uncertainty regarding the efficacy of artificial intelligence (AI) software to detect advanced subtle neoplasia, particularly flat lesions and sessile serrated lesions (SSLs), due to low prevalence in testing datasets and prospective trials. This has been highlighted as a top research priority for the field.

Methods: An AI algorithm was evaluated on four video test datasets containing 173 polyps (35,114 polyp-positive frames and 634,988 polyp-negative frames) specifically enriched with flat lesions and SSLs, including a challenging dataset containing subtle advanced neoplasia.

View Article and Find Full Text PDF
Article Synopsis
  • Patients with ulcerative colitis (UC) and low-grade dysplasia (LGD) are at a higher risk of developing advanced neoplasia (AN), such as high-grade dysplasia or colorectal cancer, highlighting the need for effective risk assessment.
  • A study involving patients diagnosed with LGD from multiple UK centers used clinicopathological data to create a risk prediction model that was validated across additional cohorts, identifying key factors like the size of LGD, resection status, inflammation severity, and multifocality.
  • The model's validated results indicate that patients meeting certain criteria can receive personalized risk assessments through a web tool, aiding in informed treatment decisions to potentially improve outcomes.
View Article and Find Full Text PDF

Background And Objectives: The UK bowel cancer screening programme (BCSP) has been established for the early detection of colorectal cancer offering colonoscopy to patients screened positive by faecal occult blood tests. In this multisite, prospective, randomised controlled trial, we aimed to compare the performance of Standard Definition Olympus Lucera (SD-OL) with Scope Guide and the High Definition Pentax HiLine (HD-PHL).

Patients And Methods: Subjects undergoing a colonoscopy as part of the UK National BCSP at four UK sites were randomised to an endoscopy list run using either SD-OL or HD-PHL.

View Article and Find Full Text PDF

Background And Aims: There are no universally accepted guidelines regarding surveillance of ulcerative colitis [UC] patients after restorative proctocolectomy and ileal pouch-anal anastomosis [IPAA]. There also exists a lack of validated quality assurance standards for performing pouchoscopy. To better understand IPAA surveillance practices in the face of this clinical equipoise, we carried out a retrospective cohort study at five inflammatory bowel disease [IBD] referral centres.

View Article and Find Full Text PDF

Computer-aided diagnosis offers a promising solution to reduce variation in colonoscopy performance. Pooled miss rates for polyps are as high as 22%, and associated interval colorectal cancers after colonoscopy are of concern. Optical biopsy, whereby in-vivo classification of polyps based on enhanced imaging replaces histopathology, has not been incorporated into routine practice because it is limited by interobserver variability and generally only meets accepted standards in expert settings.

View Article and Find Full Text PDF

Background And Aims: The inflammatory bowel diseases (IBD) are particularly common among the Ashkenazi Jewish (AJ) population. Population-specific estimates of familial risk are important for counseling; however, relatively small cohorts of AJ IBD patients have been analyzed for familial risk to date. This study aimed to recruit a new cohort of AJ IBD patients, mainly from the UK, to determine the familial occurrence of disease.

View Article and Find Full Text PDF

Objective: IBD confers an increased lifetime risk of developing colorectal cancer (CRC), and colitis-associated CRC (CA-CRC) is molecularly distinct from sporadic CRC (S-CRC). Here we have dissected the evolutionary history of CA-CRC using multiregion sequencing.

Design: Exome sequencing was performed on fresh-frozen multiple regions of carcinoma, adjacent non-cancerous mucosa and blood from 12 patients with CA-CRC (n=55 exomes), and key variants were validated with orthogonal methods.

View Article and Find Full Text PDF

Pulmonary sequestration (PMS) is a rare bronchopulmonary malformation. It has an incidence of between 0.15% to 1.

View Article and Find Full Text PDF

Objectives: To assess the ability of magnetic resonance enterography global score (MEGS) to characterise Crohn's disease (CD) response to anti-TNF-α therapy.

Methods: Thirty-six CD patients (median age 26 years, 20 males) commencing anti-TNF-α therapy with concomitant baseline MRI enterography (MRE) were identified retrospectively. Patients' clinical course was followed and correlated with subsequent MREs.

View Article and Find Full Text PDF

Objective: To investigate the effect of tumour necrosis factor (TNF)-α antagonists on MRI dynamic contrast-enhanced (DCE) and diffusion-weighted imaging (DWI) parameters in Crohn's disease (CD).

Methods: 42 patients with CD (median age 24 years; 22 females) commencing anti-TNF-α therapy with baseline and follow-up (median 51 weeks) 1.5-T MR enterography (MRE) were retrospectively identified.

View Article and Find Full Text PDF

Background: Restorative proctocolectomy with ileal pouch-anal anastomosis is the operation of choice for patients with treatment-refractory ulcerative colitis. However, after this intervention, up to 50% of patients develop pouchitis. Moreover, a subgroup will also develop inflammation in the afferent ileum proximal to the pouch, a condition named prepouch ileitis (PI).

View Article and Find Full Text PDF

Background: Mucosal abnormalities are potentially important in the primary pathogenesis of ulcerative colitis (UC). We investigated the mucosal transcriptomic expression profiles of biopsies from patients with UC and healthy controls, taken from macroscopically noninflamed tissue from the terminal ileum and 3 colonic locations with the objective of identifying abnormal molecules that might be involved in disease development.

Methods: Whole-genome transcriptional analysis was performed on intestinal biopsies taken from 24 patients with UC, 26 healthy controls, and 14 patients with Crohn's disease.

View Article and Find Full Text PDF

Crohn's disease is a chronic inflammatory condition largely affecting the terminal ileum and large bowel. A contributing cause is the failure of an adequate acute inflammatory response as a result of impaired secretion of pro-inflammatory cytokines by macrophages. This defective secretion arises from aberrant vesicle trafficking, misdirecting the cytokines to lysosomal degradation.

View Article and Find Full Text PDF

Background: Cytomegalovirus (CMV) infection has been reported in ulcerative colitis (UC), especially in severe, steroid-refractory disease. However, its role in steroid-refractoriness remains unknown. Our goals were to evaluate the prevalence of CMV disease in UC, the best diagnostic strategy, and the influence of disease activity and/or treatment in its development.

View Article and Find Full Text PDF

Background/aims: Isolated cases of acute hepatitis C, as well as hepatitis C outbreaks transmitted by health-care related procedures, have drawn attention to nosocomial transmission of HCV. The aim of this study was to investigate the current relevance of nosocomial HCV infection.

Methods: For this purpose, we performed a retrospective epidemiological analysis of all cases of acute hepatitis C diagnosed in 18 Spanish hospitals.

View Article and Find Full Text PDF

In July 2000, symptomatic acute hepatitis C was diagnosed in five patients who had attended the emergency room of a municipal hospital on the same day, about 6 weeks before. Investigation of the remaining 65 patients visited at the emergency room on that day disclosed that 8 patients had a positive anti-hepatitis C virus (anti-HCV) test and 4 of them had biochemical evidence of acute anicteric hepatitis. HCV RNA was detected in 12 of the 13 anti-HCV-positive patients.

View Article and Find Full Text PDF