bluuebunny/crossref_metadata_2025 huggingface dataset:
P306 Rectal bleeding and stool frequency are strong predictors of endoscopic and histologic activity in ulcerative colitis patients, a prospective cohort study
Authors: Alenezi T , Almushir S , Afif W , Wild G , Lakatos P , Brassard P , Bitton A , Bessissow T
Published: January 2024

Background

Rectal bleeding and increased stool frequency are the most common symptoms patients with UC report, and they are key components in most of disease activity scores. It is unclear whether the severity of patient reported outcomes (rectal bleeding or diarrhea) correlate with endoscopic or histological disease activity. The aim of this prospective study is to evaluate the role of rectal bleeding and increased stool frequency as predictors for endoscopic and mucosal activity in patients with UC.

Methods

A single-center prospective observational study was conducted from July 2012 to July 2020. Adult patients aged 18 or older, with a confirmed UC diagnosis in clinical remission for at least 3 months, presenting to the endoscopy unit for disease activity evaluation or surveillance, were included. The partial Mayo score assessed rectal bleeding and stool frequency, considering scores of zero for each as clinical remission. Active endoscopic findings were defined by an endoscopic Mayo score > 1, and active histology was assessed using the Geboes score (active disease defined as Geboes score ≥ 3.1) from rectal biopsies. Logistic regression analysis and generalized estimated equation (GEE) were employed to evaluate the predictive impact of rectal bleeding and stool frequency at different time points on endoscopic and histologic disease activity at 12 months.

Results

The study enrolled 253 patients and the analysis revealed a significant association between rectal bleeding and stool frequency scores with 12-month endoscopic and histologic activity at different time points. Rectal bleeding at 9 months (OR: 7.64, 95% CI: 1.43 - 40.90, p = 0.0175) and 12 months (OR: 19.89, 95% CI: 3.98 - 99.52, p = 0.0003) showed a significant association with active endoscopic findings at 12 month in the multivariate analysis. At 12 months, the multivariate model of rectal bleeding revealed a significant association with active histology, with OR of 11.87 (95% CI: 1.26-112.03, p = 0.0307). On the other hand, stool frequency at 12 months exhibited significant associations with the 12 months endoscopic and histologic activity with OR of 7.31 (95% CI: 2.38 - 22.49, p = 0.0005) and OR of 13.02 (95% CI: 1.60-105.74, p = 0.0163), respectively.

Conclusion

Rectal bleeding and stool frequency scores are useful tools to predict endoscopic and histological activity in UC patients.
P337 Proactive therapeutic drug monitoring of Adalimumab, but not HLADQ*A1 determination, predicts inflammatory bowel disease outcome and persistence of treatment
Authors: Carrillo Palau M , Alonso I , Morant A , Vela M , Vera B , Ramos L , Reygosa C , Medina Chico J S , Barrios Y , Franco A , Gutiérrez-Nicolás F , Jiménez A , Hernández-Guerra M
Published: January 2024

Background

Anti-TNF drugs have proven effective in managing Inflammatory Bowel Disease (IBD), but a significant percentage of patients exhibit primary or secondary non-response. Therapeutic drug monitoring (TDM) is a valuable tool for optimizing patient management. HLA-DQA1*05 gene has been investigated as a potential marker for immunogenicity and loss of response to anti-TNF therapy.This prospective, multicentric study aimed to assess the clinical impact of determining Adalimumab (ADA) levels and anti-adalimumab antibodies (Abs) in IBD patients and the influence of the HLA-DQA1*05 allele on the response and maintenance of ADA treatment over a 24-month follow-up.

Methods

Patients initiating ADA treatment between October 2020 and October 2022 were enrolled. Demographic data and IBD characteristics were recorded. Clinical Activity Index, C reactive protein (CRP), faecal calprotectin (FC), endoscopy or radiological activity, Global Physician Assesment (GPA) and PRO (by IBDQ-9) were prospectively collected at baseline and at the same time that ADA levels: week 4, 10, 30 and 12 months. HLA-DQA1*05 was genotyped at baseline. Pearson coefficient was utilized to assess correlations between ADA levels and disease activity.

Results

We included 170 (age 42±17 years, 54% female) IBD patients (74% Crohn`s Disease, 24% Ulcerative Colitis and 2% Indeterminate colitis) who started ADA (85% naïve to anti-TNF). At baseline, 80% had an active disease (GPA=1); CRP and FC were 10.72 ±17.85 mg/L and 568 ±775 µg/g; PRO at baseline was 63±8.6. HLA was determined in 167 patients, of whom 71 (42%) were HLA-DQA1*05 positives. Median follow up was 17 months. No correlation between HLA and drug levels or Abs was founded. ADA levels at the end of induction was correlated with ADA levels during follow up. ADA serum concentration >7 µg/mL at weeks 4 and 10 correlated with improved clinical response at corresponding time points (p<0.001). Patients with ADA levels >7 µg/mL at week 10 demonstrated better disease control at 12 months. 41 patients stopped ADA. It was associated with active disease, low ADA levels, and adverse clinical and laboratory markers. HLA-DQA1*05 positivity did not correlate with adverse reactions or Abs during the observational period. A significative improvement in PROs in patients who started treatment with ADAL (62.73 at baseline and 69.42 at week 30) (p<0.001) was observed.

Conclusion

Early Drug level monitoring of Adalimumab may improve the management of IBD patients. PCR, CF and GPA at week 10 may predict treatment failure. ADA levels >7 µg/mL is associated with a better clinical response in short and long-term, independent of HLADQA1*05.
P341 Clinical Characteristics and Outcomes of Crohn’s Disease with Upper Gastrointestinal Involvement: A Comprehensive Retrospective Cohort Study
Authors: Hsu W C , Le P H , Kuo C J , Yeh P J , Lai M W , Wu R C , Chen C M , Chiu C T , Su M Y , Pan Y B
Published: January 2024

Background

Crohn's Disease (CD) affects the entire gastrointestinal tract, predominantly involving the terminal ileum and colon. However, the incidence and implications of upper gastrointestinal tract involvement in CD are often underestimated and underreported, especially in Asian populations. This study provides a comprehensive evaluation of the clinical characteristics and outcomes associated with UGI involvement in CD.

Methods

We conducted a retrospective cohort study at Chang Gung Memorial Hospital, Linkou, from January 2001 to June 2023, including CD patients with consistent follow-up records. Patients were categorized into two groups based on UGI involvement: Montreal L4 and non-L4. Comparative analyses were performed between the groups regarding baseline characteristics, new-onset complications post L4 disease diagnosis, and clinical outcomes.

Results

The study included 223 CD patients, 114 in the L4 group and 109 in the non-L4 group, with an average follow-up of 40.6 months. Initially, the L4 group showed higher smoking prevalence (21.1% vs. 5.5%, P<0.001), higher Crohn’s Disease Activity Index (CDAI) scores (302.6±85.6 vs. 272.8±106.3, P=0.023), increased stricture disease (Montreal B2) incidence (55% vs. 48.2%, P<0.001), and more frequent use of biologics (12.3% vs.3.7%, P=0.021) and proton pump inhibitors (64.9% vs. 52%, P=0.014). They also had lower albumin levels (3.6±0.8 vs. 3.9±0.7, P=0.011) and reduced peri-anal (14.9% vs. 26.8%, P=0.026) and fistulizing disease incidences (14% vs. 26.6%, P=0.016). At follow-up end, the L4 group continued to exhibit higher CDAI scores (153.6±98.7 vs. 114.4±71.8, P = 0.001), increased hospitalization rates (0.6±1.1 vs. 0.3±0.5 times/year, P=0.009), elevated C-reactive protein levels (15.2±37.8 vs. 6.9±15.1, P=0.036), and decreased albumin levels (4±0.7 vs. 4.2±0.4, P=0.018). Though they had a lower incidence of new-onset perianal fistula (6.7% vs. 3.7%, P=0.041), the L4 group had higher incidences of most new-onset CD-related complications, including strictures (44% vs. 20.2%, P<0.001), enter enteral fistulae (11.9% vs. 3.5%, P=0.036), and intraabdominal abscesses (17.4% vs. 5.3%, P=0.009).

Conclusion

CD with UGI involvement is associated with higher disease activity and an increased risk of IBD-related complications. Comprehensive assessments at diagnosis and aggressive treatments are crucial for these patients to mitigate poorer outcomes.
P372 Barriers and facilitators of the transition from paediatric to adult care in inflammatory bowel disease: A Western Canadian perspective
Authors: Bihari A , Wine E , Seow C H , Goodman K J , Kroeker K
Published: January 2024

Background

Patients diagnosed with inflammatory bowel disease (IBD) in childhood/adolescence face additional challenges compared to those diagnosed in adulthood, including more extensive disease and higher risk of complications. The need to undergo transition from paediatric to adult care is associated with an increase in health care utilization and a decrease in adherence to medical appointments and medications. An effective transition may reduce these negative impacts, but there remains a need to engage the stakeholders involved in transition to identify ways to improve the transition process. This study aims to describe the perspectives of key stakeholders - patients, parents, and health care providers - on barriers and facilitators of a successful transition from paediatric to adult care.

Methods

We conducted a qualitative description study informed by naturalistic inquiry. Patients, parents, and providers from Western Canada were recruited using purposive and snowball sampling for a virtual semi-structured interview. Interviews were recorded, transcribed, and then analyzed by latent content analysis.

Results

We interviewed 17 patients, 13 parents, and 15 providers. Preparedness as a facilitator was the only theme to emerge across all groups. Groups described preparedness as knowing disease history (patients & providers), expectations of adult care (providers), and having a peer support program (parents). A supportive adult care team was identified as a facilitator by patients (n=10) and parents (n=4) who described an adult care team as one with open lines of communication, and one that is welcoming and caring. Additional facilitator themes included patient characteristics (i.e., patients who were mature, organized, and independent), and supportive parents and home environment, where a patient’s self-confidence and ability to advocate for themselves was encouraged. A barrier theme of patient factors was characterized by providers (n=8) and parents (n=4) as patients in denial of their IBD or who had mental health comorbidities. In the theme of hovering parents and family factors, providers (n=12) described parents who were reluctant to transfer disease responsibility to their child, and families with economic and/or personal challenges. Additional barrier themes included the need to navigate a new health care system and travel to clinic.

Conclusion

The results suggest a uniform agreement is necessary amongst stakeholders to ensure the development of resources aimed at preparing patients. Our study found differences in how stakeholder groups characterize the barriers and facilitators of transition. Future research should engage multiple stakeholder groups in designing transition interventions and supports for patients with IBD.
P379 PD-1-positive cells contribute to the diagnosis of Inflammatory Bowel Disease and can aid in predicting response to vedolizumab
Authors: Kim M K , Jo S I , Kim S Y , Lim H , Kang H S , Moon S , Ye B D , Soh J S , Hwang S W
Published: January 2024

Background

Differentiating inflammatory bowel disease (IBD) from other inflammatory diseases is often challenging. Programmed cell death protein-1 (PD-1) is expressed in T cells and is an indicator of their exhaustion. The role of PD-1 expression in diagnosing IBD and predicting the response of biologic agents remains inconclusive.

Methods

In this study, endoscopic biopsy samples of 19 patients diagnosed with IBD and other inflammatory diseases were analysed using multiplexed immunohistochemistry . Other inflammatory diseases comprised five patients with intestinal tuberculosis, and five with intestinal Behçet’s disease. Additionally, a separate prospectively maintained "vedolizumab (VDZ) cohort", established in 12 ulcerative colitis(UC) patients who underwent endoscopic biopsy before VDZ administration was analysed to predict response to VDZ.

Results

In the immunohistochemistry analysis, the cell density of T cell subsets, including helper T cell (Th), cytotoxic T cell (Tc), regulatory T cell (Treg), PD-1+ cell, PD-1+ Th, PD-1+ Tc, and PD-1+ Treg was investigated and compared between IBD and other inflammatory disease. Cell densities of PD-1+ cells (p=0.028), PD-1+ Th (p=0.008), and PD-1+ Treg (p=0.024) were higher in IBD compared with other inflammatory disease.(Figure 1) In addition, the proportion of PD-1+ cells in Th and Treg was higher in the IBD group than in the other inflammatory disease group (median 7% vs. 3%, p=0.008; median 6% vs. 2%, p=0.004, respectively). Comparing within IBD, the cell density of Treg was higher in Crohn’s disease(CD) than in UC (p=0.042), whilst the cell density of Tc was higher in CD than in UC with marginal statistical significance (p=0.066). In the VDZ cohort, patients with a 14-week steroid-free clinical response had higher levels of PD-1+ cells (p=0.026), PD-1+ Th (p=0.026), and PD-1+ Treg (p=0.041) than the no response group.(Table 1)

Conclusion

We explored the relationship between PD-1 expression and IBD using multiplexed immunohistochemistry. We compared IBD and other inflammatory disease in their expression of various immune cells including PD-1+ cells, and found IBD had higher PD-1 expression, as well as higher PD-1+ Th and PD-1+ Treg compared with other inflammatory diseases. In addition, VDZ-responsive patients had higher PD-1 expression. Our study confirmed the difference in PD-1 expression in IBD and other inflammatory diseases and revealed that PD-1 expression could be a predictive marker for VDZ responsiveness.
P396 Bowel ultrasound training in European and Mediterranean Countries: results of a survey
Authors: Costantino A , Af Björkesten C , Vaiano M L , Banai H , Schreiner P , Zignani N , Penagini R
Published: January 2024

Background

Bowel ultrasound (US) is a cost-effective, non-invasive, accurate, and readily available tool for the diagnosis and monitoring of patients with inflammatory bowel disease (IBD). Moreover, it can be an accurate tool in the hands of gastroenterologists for the initial assessment of patients with chronic and acute intestinal disorders -such as abdominal pain and diarrhoea- to rule in and out organic causes.

Currently, it is not known how many European residents in gastroenterology or internal medicine who care for IBD patients have the opportunity to have a bowel US training. Tha aims of our study were to investigate the bowel US training in Europe and the perception of utility of this diagnostic technique.

Methods

The participants of the survey were residents from different Countries who voluntarily chose to take part in one of the two first editions of the bowel US course, one of the optional courses held during the UEG Summer School in Prague (2022 and 2023).

Participants answered an initial test in a digital anonymous questionnaire.

Results

Among the 135 participants in the course, 104 (77%) answered all the questions. Respondents were from 28 European and Mediterranean area Countries.

The majority of respondents (60.6%) were residents in their 3rd and 4th year of specialization (men 58.7%). Among the respondents, 61 (58.7%) stated they had a general abdominal US training period during their residency (62.5% of them reporting <100 exams performed). (Figure 1) It was not offered any bowel US training to 76% of residents. (Figure 2) Among the respondents, the Italian residents showed the highest probability to have a bowel US training (7/13, 53,8%). At a Likert scale, 96.2% stated that bowel US is important for their future profession (Figure 3) and 93.3% stated it is important for treatment decision in gastroenterology. (Figure 4)

Conclusion

Our survey reveals, despite the possible limits given by the response and selection bias, that in Europe bowel US training is deficient and heterogeneous.

Only one every four participants received a bowel US training during their residency, despite bowel US knowledge is considered a necessary skill by approximately 95% of young gastroenterologists who participated in the course. Since less than 2/3 have a US period during their residency (often insufficient), it is likely that most residents interested in bowel US are forced to acquire this skill attending other specific courses during or after their residency.

Solutions may be represented by the implementation of specific courses or with the institution of minimum bowel US training level during the residency.
P400 Experience with the use of intestinal ultrasound and application of the Milan Ultrasound Criteria in Colombian patients with ulcerative colitis
Authors: Parra Izquierdo L V , Vargas M , Frías-Ordoñez J , Ibañez E , Rios S , Orduz G , Florez-Sarmiento C
Published: January 2024

Background

Intestinal ultrasound (IUS) has been reported to be accurate in the diagnosis of ulcerative colitis (UC) and can also be applied to determine the extent of the disease, its severity and location of inflammation, also, is fast, effective, non-invasive, relatively inexpensive, and can be performed in health care centres of varying complexity. The aim of this study is to assess the validity and reproducibility of IUS in patients with UC, and evaluate the Milan Ultrasound Criteria (MUC) as a predictor of activity in UC.

Methods

analytical observational study in adults and paediatric patients with UC with different degrees of activity, and with a need for colonoscopy. Clinical, biochemical, endoscopic, and ultrasonographic variables were collected. Logistic regression analysis was performed. The presence of endoscopically active disease was the outcome (or dependent variable). All IUS parameters described were independent variables. Univariate analysis was used to identify candidate predictors. A significance level of 0.05 was used in all tests.

Results

Thirty-six subjects were included, predominantly male, 75% (27/36) were in endoscopic remission (Mayo score 0 -1), while 25% (9/36) had endoscopic activity (Mayo endoscopic score > 2). Median Colonic wall thickening (CWT) in patients in endoscopic remission (Mayo score 0-1) was 2.4 (IQR 2-2.8) mm compared to 3.1 (IQR 2.15-4.2) mm in patients with endoscopically active disease (Mayo score 2) with no statistically significant difference p=0.148. Colonic wall flow at power doppler (CWF) was present in 22.2 % (6/27) of patients in endoscopic remission compared to 44.4 % (4/9) of patients showing endoscopic activity (p=0.148). Endoscopic activity (p = 0.264). Loss of elasticity and peristalsis was present in 11.1% (3/27) patients in remission compared to 66.6% (6/9) in patients with activity (p=0.003). As for mesenteric fat hypertrophy, it was found in 44.4% (4/9) of patients with activity compared to 14.8% (4/27) in remission (p=0.098). Enlarged mesenteric nodes were found in 22.2% (2/9) patients with activity compared to 14.8% (4/27) in remission (p=0.615). Free fluid was present in 22.2% (2/9) of patients with activity compared to 7.4% (2/27) in remission (p=0.315). The mean value of the MUC score was 4.025 (observer 1 mean 3.85 with S: 77% and E: 70%, observer 2 mean 3.99, with S: 66% and E: 77%). The degree of interobserver agreement was 0.957.

Conclusion

IUS is a useful and effective tool in the evaluation of disease activity in patients with UC, with a MUC measurement of 4.025 suggesting an adequate diagnostic performance of this score, being the best cut-off point to discriminate between activity versus remission.
P419 Proximal Crohn’s disease location is associated with a more benign course of perianal Crohn’s disease (the PERIAPROX study)
Authors: Romero-Mascarell C , Giordano A , Riestra S , Martín-Arranz M D , Ricart E , Gisbert J P , Brunet-Mas E , Rivas Rivas C , Calafat M , Fernández Salgado E , Guardiola J , Gomollón F , Sierra Moros E , Hernández Camba A , Iglesias E , De Prado Á , Martinez-Montiel P , Mesonero F , Varela P , de Castro L , Madero Velázquez L , Lázaro Pérez-Calle J , Esteve M , Rodríguez-Lago I , Bermejo F , Lorente R , Sicilia B , Castro-Poceiro J , Gordillo J , Huguet J M , Ponferrada A , Sierra M , Bujanda L , Marín-Jiménez I , Pascual I , Vera I , Sesé E , Vega P , Domènech E , Garcia-Planella E
Published: January 2024

Background

Proximal Crohn’s disease (CD) location (L4 according to the Montreal Classification) is associated with a more severe course with higher risk of abdominal surgery. However, little is known about the relation with perianal disease. The aim of our study was to investigate the impact of L4 disease location on perianal disease incidence and clinical course.

Methods

A case-control study was conducted in the prospectively maintained ENEIDA database for all CD with and without L4 location between January 2005 and March 2023. Demographic data, disease characteristics, perianal disease diagnosis and evolution according to biologic therapy and surgery requirement were collected. Demographic data, CD characteristics, perianal disease diagnosis and course were analyzed. Cox proportional hazards and Kaplan-Meier methods were used for the analysis of perianal incidence, and biologic and surgery requirement.

Results

A cohort of 14022 CD patients were included in the analysis. The mean follow-up duration was 6.4 years (SD 4.9). L4 location showed a lower prevalence of perianal disease (18.0 vs 19.9%, p=0.018), with lower rate of fistulas (60.9 vs 66.1%, p=0.021) and perianal abscesses (33.5 vs 39.4%, p=0.013). Perianal disease and L4 were associated with male sex (OR 1.29, p<0.001), younger age (43 vs 44), and the structuring phenotype (OR 2.14, p<0.001). L4 location was associated with a lower incidence of perianal disease (HR 0.891, p=0.041), while proctitis was associated with a higher risk (HR=2.161, p<0.001). L4 location was also associated with a lower requirement for biologics (HR 0.712, p=0.023), along with advanced age (HR 0.988, p<0.001). Proctitis (HR 1.292) and a history of perianal surgery (3.373) were associated with a higher requirement for biologics. At univariate analysis, L4 location was associated with a lower requirement of surgery (HR 0.833), however at multivariate analysis this finding was not confirmed (p=0.525). Instead, a history of active smoking (HR 1.419), the use of biologics (HR 2.262), and CD penetrating pattern (HR 1.277) were associated with a higher requirement for perianal surgery.

Conclusion

L4 location is associated with a lower incidence of perianal disease and a more benign course with lower requirement for biologics and surgery.
P428 Nutritional, Muscular status and micronutrient deficiencies in patients with Inflammatory Bowel Disease
Authors: Han J , Song H J , Kim H U , Kang M S , Kang K S
Published: January 2024

Background

Malnutrition and micronutrient deficiencies are common in inflammatory bowel disease (IBD). Nutrient deficiencies increase the morbidity and complications of IBD. The aim of this study was to evaluate the nutritional and muscular status and identify micronutrient deficiencies of patients with IBD receiving treatment.

Methods

A total of 105 patients with IBD were enrolled prospectively in the department of gastroenterology and pediatrics from June 2019 to October 2021. To obtain objective data, iron, ferritin, phosphate, folate, Mg, 25-OH vitamin D, vitamin B12, and Zinc were measured in the patient's serum. In addition, body composition analysis was performed using bioelectrical impedance analysis to gain information regarding muscular status.

Results

There were 51 patients with ulcerative colitis (UC), 54 with Crohn's disease (CD), and the gender ratio (M:F) was 54:51. The average age was 37±18 years, which was significantly lower in patients with CD than UC (28.6±15.9 vs. 45.3±16.3, p<0.001). The mean body mass index (BMI) was 22.0 ± 3.7 kg/m2, lower in patients with CD than UC (21.2 ± 3.8 kg/m2, vs. 22.0 ± 3.3 kg/m2, p=0.030). The disease activity of the patients was 64.8% in remission, with 17.1% mild, 15.2% moderate, and 2.9% severe. In the UC and CD patient groups, skeletal muscle index(SMI) and adjusted skeletal muscle mass were lower in patients with CD compared to UC.(SMI : 35.8±5.5 vs. 32.8±4.7 %, p<0.004, adjusted skeletal muscle : 8.2±1.9 vs. 7.0±1.5 kg/m2, p<0.001) However, there was no difference of SMI and adjusted skeletal muscle according to disease activity in both UC and CD patients (Table 1). Iron was lower in patients with CD compared to UC (63.3 ± 42.5 vs. 82.8 ± 44.0 ug/dL, p=0.024). Ferritin, phosphorus, folic acid, vitamin B12, and zinc were also within normal limits. Magnesium was lower in patients with CD compared to UC (2.08 ± 0.15 vs. 2.15 ± 0.19, p=0.036 mg/dL). Vitamin D levels showed insufficient vitamin D in patients with UC and vitamin D deficiency (below 20 ng/mL) in patients with CD (20.1 ± 10.6 vs. 19.0 ± 9.9 ng/mL, p = 0.567) (Table 2).

Conclusion

Nutritional status of patients with IBD is favorable, and the lack of trace elements, specifically iron, magnesium, and vitamin D, and reduced skeletal muscle mass were observed to be prominent in patients with CD compared to UC.
P445 Wireless capsule endoscopy reading support for Crohn’s disease patients using deep neural networks with an active learning method
Authors: Rouveyre R , Subileau-Langlois T , Gomez T , Mouchère H , Bourreille A , Leberre C
Published: January 2024

Background

Artificial intelligence (AI) systems, in particular neural networks (NN), have been developed to detect lesions in wireless capsule endoscopy (WCE) in patients with Crohn’s disease (CD) in order to ease their reading. Despite acceptable performance on individual images, these tools do not analyze entire videos and require a large amount of labeled data. Active learning (AL) methods have already been used, proving their ability to limit labeling cost without reducing NN performance. The aim of this study was to evaluate several AL models in order to train an AI system able to differentiate normal and pathological entire videos with a limited labeled dataset.

Methods

Firstly, 76 WCEs of CD patients were used to automate the detection of the first and last image of the small bowel. They were identified by an expert and then used for training, validation and test of a NN. The model associated with the Viterbi algorithm predicted boundaries location and was compared with expert annotations.

Secondly, 4286 images from the Crohn-IPI database¹ were used to train another NN to classify pathological or normal images. An image was considered pathological if it contained erythema, oedema, ulceration or stenosis. Four AL models with several selection criteria² were tested on a limited labeled dataset and their classification performance (normal/pathological image) was evaluated.

Finally, 42 WCEs were used to assess performance of a pre-trained AL model to predict the normal or pathological nature of entire videos.

Results

Overall, the model detected the pylorus compared with experts with a median deviation (IQR) of 3 images (66.5) and the last ileal image with a median deviation of 98 images (336). A history of ileocolic resection non-significantly impaired the last ileal image location, with a median difference of 203 images (812, p=0.59).

None of the four AL models showed superiority in classifying pathological or normal image, with a sensitivity of 60% and a specificity of 98%.

Finally, the AL pre-trained NN assessed the pathological/normal status of entire videos with a sensitivity of 83% and a specificity of 50%.

Conclusion

Our study suggests the feasibility and efficiency of NN to identify the first and last image of the small bowel on CD patients WCE. Performances of the four AL models were similar but remained sufficient given the small amount of labeled data used. Prediction of the pathological/normal status of entire videos by AI systems seems feasible, but requires optimization to obtain acceptable results for current practice.

1. De Maissin A et al. Multi-expert annotation of Crohn's disease(...) neural network, Endosc IntOpen(2021)

2. Wang K et al. Cost-Effective Active Learning for Deep Image Classification, IEEE (...) Technology(2017)
P454 Systemic free thiols associate with clinical and biochemical disease activity in Inflammatory Bowel Disease: a prospective diagnostic validation study
Authors: Geertsema S , Holstein H J , Bulthuis M L C , Faber K N , van Goor H , Dijkstra G , Bourgonje A R
Published: January 2024

Background

In the pathophysiology of inflammatory bowel diseases (IBD), oxidative stress plays an important role. Lower levels of plasma free thiols (FT) reflect a higher oxidative stress burden and correlate with IBD disease activity. However, their clinical significance as biomarker for disease activity remains unclear. This study aimed to prospectively validate the utility of plasma FT levels as biomarker for clinical, biochemical, and endoscopic disease activity in patients with IBD.

Methods

In an ongoing prospective diagnostic trial aiming to include 100 IBD patients, we conducted an interim analysis of plasma FT levels in 52 patients with IBD (24 Crohn's disease [CD], 21 ulcerative colitis [UC], and 7 patients with undetermined IBD). Clinical disease activity was quantified by the Harvey-Bradshaw Index (HBI) for CD and Simple Clinical Colitis Activity Index (SCCAI) for UC. Biochemical disease activity was determined by measuring blood C-reactive protein [CRP] and faecal calprotectin [fCal]). Endoscopic disease activity was quantified with the Mayo endoscopic subscore for UC and the Simple Endoscopic Score (SES-CD) for CD. Plasma FT levels were assessed for correlations with disease activity parameters using linear and logistic regressions models. Discriminative capacity of biomarkers was evaluated through calculating receiver operating characteristics (ROC) statistics.

Results

Plasma FT levels were significantly negatively correlated in clinical parameters, like HBI (r = -0.53, p < 0.05) (Fig. 1A). Other inflammatory biomarkers, like CRP, were also negatively correlated with plasma FT levels and were reduced in patients with active IBD (r = -0.43, p < 0.05) (Fig. 1B). Plasma FT levels accurately discriminated between CD patients with clinically quiescent (HBI < 5) and active disease (HBI ≥ 5) (AUC = 0.80, p = 0.02, Fig. 1C), better than fCal (AUC = 0.55, p = 0.83). Plasma FT were not significantly different for biochemically quiescent (CRP < 5 mg/l) and active (CRP ≥ 5mg/l) disease (AUC = 0.69, p = 0.20, Fig. 1D). Both Mayo and SES-CD scores, after adjusting for confounders, also exhibited a trend towards negative association with plasma FT levels (Fig. 1E).

Figure 1

Conclusion

Further completion of the trial will reveal whether systemic FT levels will reflect endoscopically observed disease activity, and this interim analysis shows strong correlations FT levels and parameters of clinically and biochemically active disease. Measuring systemic FTs in IBD may be a promising, minimally invasive strategy to monitor IBD disease activity.

Funding

None
P461 Deep learning model for endoscopic differential diagnosis between intestinal lymphoma and Crohn's disease: a multicenter study
Authors: Gu Y , Zhao L , Zhang Y , Zou D
Published: January 2024

Background

Primary and secondary intestinal lymphoma (IL) are a relatively rare cancer, while easily misdiagnosed due to the unclear aetiology and unspecific clinical symptoms. Moreover, the endoscopic features of IL vary depending on pathological types, making it difficult to distinguish from Crohn's disease (CD). This study aims to develop deep learning models based on endoscopic images, facilitating the differential diagnosis of IL and CD.

Methods

We retrospectively recruited 271 patients with IL and 232 patients with CD from 6 tertiary centres in China. With out-of-focus or poor-bowel-prepared images excluded, we used 1739 IL and 1649 CD images for internal and external validation to build deep learning models. For internal validation, we used five-fold cross-validation with 1517 IL images and 1428 CD images from 5 centres randomly assigned without any patient overlap. 222 IL and 221 CD images from the 6th centre were used for independent external validation to measure the generalization ability of models. Further, we compared the performance of models with that of clinical physicians consisting of 2 junior physicians and 2 endoscopy specialists with more than ten years of clinical experience. We evaluated models using metrics such as accuracy, sensitivity, specificity, and the area under the receiver operating characteristic curve (AUC) and used the kappa statistic to measure the inter-rater reliability between models and clinical physicians.

Results

We developed multiple convolutional neural network models, including ResNet18, ResNet34, ResNet50, VGG16, VGG19, DenseNet121, Inception v3, and Xception. The top 3 models in the internal validation were Inception v3, Xception, and DenseNet121. Inception v3 showed the best performance (accuracy: 83.1%; AUC: 0.910), while Xception performed better on average (average accuracy: 76.8%; average AUC: 0.834). In the external validation, the top 3 models were Inception v3, DenseNet121, and VGG19. Inception v3 achieved the highest accuracy of 81.9%, while DenseNet121 had the best AUC of 0.903. Compared with clinical physicians, Inception v3 performed better than junior physicians (average accuracy: 67.2%) and showed good agreement with the best endoscopy specialist (kappa: 0.604, p<0.05).

Conclusion

Convolutional neural network models using endoscopic images were able to differentiate PIL from CD, with better-diagnosing performance than junior physicians, good agreement with specialists, and good generation ability, which were expected to assist clinical physicians lacking experience to differentiate PIL and CD more precisely under endoscope.
P471 Tight control strategy improves combined histologic and endoscopic remission in ulcerative colitis
Authors: Rodrigues I , Fernandes S , Botto I , Saraiva S , Bernardo S , Gonçalves A R , Moura Santos P , Valente A , Araújo Correia L
Published: January 2024

Background

Increasing evidence suggests that combined histological and endoscopic remission associates with less adverse outcomes (hospitalization and corticosteroid therapy) and predicts a quiescent course of ulcerative colitis (UC). However, few patients can achieve this target with the drugs currently available. A tight control strategy with a proactive treatment escalation based on biomarkers may improve these results.

Methods

Retrospective, single-center cohort study including consecutive patients with UC with severe endoscopic disease (Mayo endoscopic subscore=3) and subsequent endoscopic, histologic and faecal calprotectin (FCP) evaluation. Data concerning demographic, disease phenotype, laboratory findings and treatment were collected. We defined tight control strategy as therapeutic escalation in >50% of cases where FCP≥250ug/g. Therapeutic escalation was defined as the start, switch or dose increment/interval shortening of biologic therapies/small molecules. Endoscopic remission was defined as a Mayo endoscopic subscore ≤1. Histologic remission was defined as the absence of ulcers, erosions and neutrophils in the lamina propria.

Results

One hundred and seven patients were included, 56.0% male and 63.6% with extensive UC. Thirty-four patients (31.8%) were included in the tight control group. During follow up, 52 patients (48.6%) achieved endoscopic remission, 29 (27.1%) histological remission and 27 (25.1%) combined remission. Patients in the tight control group achieved combined remission more frequently (38.2 vs 19.2%, P=0.05). On multivariate analysis including age at diagnosis, duration and extension of disease and therapy received, a tight control strategy was independently related to a higher probability of combined remission: OR 2.768 IC95% 1.056-7.255, P=0.038.

Conclusion

A tight control strategy based on FCP was associated with higher combined histological and endoscopic remission in UC.
P473 Comparison of clinical performance of fecal calprotectin of laboratory methods with lateral flow based POC and home tests
Authors: Reinhard C , Pénager R , Ueberschlag M E , Kräuchi S , Trapani-Vondran D , Kupchak P , Schuster T
Published: January 2024

Background

To confirm an IBD diagnosis and manage IBD patients, endoscopy is the gold standard to assess mucosal inflammation. Fecal calprotectin (fCAL) is a reliable biomarker of intestinal inflammation that highly correlates with endoscopic and histological findings. Fecal calprotectin testing is recommended in most IBD guidelines for diagnosis and disease course evaluation. Different assay technologies exist that need to measure fecal calprotectin comparably. These range from classic enzyme linked immunosorbent assays (ELISA), particle enhance turbidimetric immuno assays (PETIA), and rapid lateral flow assays (LFIA). LFIA[AL1] [RC2] s can be read by conventional tabletop readers or by everyday smartphone applications using the phone’s camera to acquire an image, detect the test cassette and calculate a quantitative result. As there is no international standard to date, fecal calprotectin assay manufacturers rely on their own internal calprotectin standardization. This study compared four different assays measuring the same clinical samples.

Methods

The 128 raw stool samples that were analyzed in this study were obtained from patients that presented with signs and symptoms suggesting intestinal inflammation and underwent endoscopic evaluation to establish or exclude an IBD diagnosis. Samples were extracted with the BÜHLMANN CALEX® Cap stool extraction device. Each extract was then measured on the BÜHLMANN fCAL® ELISA, fCAL® turbo (PETIA), Quantum Blue® fCAL extended lateral flow assay and smartphone based IBDoc® fCAL home test. For the home test, two phones, iPhone 11 and Samsung Galaxy S7, were used to measure the lateral flow test cassettes. Each sample was measured one time on each assay and Receiver Operating Characteristic (ROC) curve analysis was performed and total agreement between each method was calculated.

Results

ROC curves were generated to assess the ability of each assay to differentiate between IBS and IBD with area under the curve (AUC) values ranging from 0.827 (Samsung Galaxy S7 to 0.835 (fCAL turbo). There was no significant difference between the methods. Commonly used cut-offs in the assessment of IBD patients are 100 and 250 µg/g, respectively. Positive and negative percent agreement (PPA/NPA) between the smartphone-based home test and the laboratory assays was calculated. The PPA was above 90% for all methods while the NPA was above 88% for all methods.

Conclusion

The results presented here show that the four BÜHLMANN assays measure fecal calprotectin extremely comparably and show an excellent clinical performance. This allows for the use of the methods interchangeably, depending on the needs of the patients and their care team.
P485 Do intestinal ultrasound scores have a role in the diagnosis of post-operative recurrence?
Authors: Amor Costa C , Suarez Ferrer C , Poza Cordon J , Rueda Garcia J L , Sanchez Azofra M , Martin-Arranz E , Yebra Carmona J , Spigarelli Rabago I , Amiama Roig C , Gonzalez Diaz I , Garcia Ramirez L , Martin-Arranz M D
Published: January 2024

Background

Ileocolonoscopy and Rutgeerts endoscopic score remains the gold standard to evaluate post-operative recurrence (POR) in Crohn's disease (CD) patients. Intestinal ultrasound (IUS) is proposed as a non-invasive alternative to ileocolonoscopy for the diagnosis of POR, with a sensitivity of 94% and specificity of 84%. There are several IUS scores that evaluate CD disease activity such as SUS-CD (validated), IBUS-SAS and Simple US Score, which have not yet been studied in the diagnosis of POR. The aim of this study is to assess whether IUS parameters and ultrasound scores correlate with endoscopy in the diagnosis of POR.

Methods

A unicentric retrospective study was performed. There were included patients with CD with both an ileocolonoscopy and intestinal ultrasound performed for the detection of POR, the time between tests was less than 6 months and there was no therapeutic change between tests. Endoscopic POR was evaluated with Rutgeers score (RS), considering POR RS ≥i2b. In IUS, were used: Simple US Score, SUS-CD and IBUS-SAS.

Results

103 patients were included, baseline characteristics are in Table 1. 30 patients (29.1%) had no endoscopic POR, 22 (21.4%) had RS i2a, 12 (11.6%) RS i2b and 39 (37.9%) had severe POR (RS i3-i4). The mean wall thickness measured by IUS in patients without endoscopic POR was 2.7 mm (SD +/- 1.3) versus 5.0 (SD +/- 1.7) in patients with RS ≥i2b (p 0.001). Hyperemia (Limberg >1) was present in 60 patients (82.2%) with RS ≥i2a vs in 4 patients (13.3%) without endoscopic POR (p 0.001). Both hyperemia and wall thickness had a sensitivity of 89.0% and specificity of 76.7% in the diagnosis of POR.

The mean values for IUS scores were: Simple US Score 5.5 (SD +/- 3.1), SUS-CD 2.1 (SD +/- 1.8) and IBUS-SAS 32.9 (SD +/- 26.3). There were positive correlation for IUS scores (Simple US Score r 0.68, SUS-CD r 0.68 and IBUS-SAS r 0.67) with RS (p <0.0001). For the Simple US Score an area under the ROC curve (AUC) of 84.13% (95% CI 76.81 – 91.45) was obtained, with a score ≥3, the sensitivity (S) was 82.19% and specificity (E) 80.0%. IBUS-SAS presented an AUC of 84.93% (95% CI 77.98 - 91.87), a result ≥15 granted a S 82.19% and E 80.0%. The SUS-CD index had an AUC of 83.38% (95% CI 75.55 - 91.20), a result ≥1 presented S 82.19% and E 80.0%.

Conclusion

In our experience, IUS scores (IBUS-SAS, SUS-CD and Simple US Score) show a high sensitivity and specificity in the diagnosis of POR. The three scores had AUC greater than 80%, IBUS-SAS showed slightly higher AUC results.
P529 Assessing patient-perceived burden of disease in Crohn’s disease: a novel scoring approach in a real-world Australasian cohort
Authors: Pipicella J L , Gu B , Palmer L , Connor S J , Wilson W , Andrews J M
Published: January 2024

Background

The prevalence and burden of inflammatory bowel diseases (IBD) including Crohn’s disease (CD) are rising globally. We present a novel score to evaluate the patient-perceived burden of disease (PPBoD) in CD, and explored it in a large real-world Australasian cohort.

Methods

The Crohn’s Colitis Care (CCCare) Clinical Registry was interrogated in October 2023. Adults with CD across 17 IBD centres with an outpatient encounter in the last 14 months were included. A novel PPBoD score was designed for CD, which included patient-reported components from the Harvey-Bradshaw index (abdominal pain and patient-rated general wellbeing) as well as nocturnal bowel actions, defecation urgency and stool frequency. The PPBoD score was calculated as detailed in figure 1. A total score of 0 was defined as no PPBoD, 1-2 as mild, 3-4 as moderate and ≥ 5 as significant PPBoD. Correlations amongst PPBoD and demographics, disease and treatment factors were explored.

Results

A total of 3461 people with CD were assessed in the last 14 months and 3233 (93.4%) had adequate data to calculate PPBoD. Of these, 80.0% had either no or mild PPBoD (table 1). While gender varied significantly between PPBoD categories, age and BMI did not. People with lower PPBoD were more likely to be receiving advanced therapies and had lower rates of steroid use than those with higher PPBoD. There were no significant differences in the use of immunomodulators and/or aminosalicylates across PPBoD categories. The cohort was geographically dispersed across Australia (n = 2414, 74.7%) and New Zealand (n = 819, 25.3%). There was significantly higher PPBoD in New Zealand compared to Australia but notably people in New Zealand were less likely to be receiving advanced therapies (p < 0.001). In the subset of 1074 people (33.2%) with a recent faecal calprotectin, those with no PPBoD were more likely to have biochemical remission (faecal calprotectin < 100 μg/g). Data were available to assess endoscopic and radiological remission in 1049 people (32.4%); those with no PPBoD were more likely to be in remission. Less than 1% of people with no PPBoD had any days out of role due to CD, whereas those with higher PPBoD had more days out of role (Table 1).

Conclusion

We present a novel consumer-focused score to quantify PPBoD in CD. Within this geographically dispersed cohort, the majority had either no or mild PPBoD. Advanced therapy use appeared to be protective against high PPBoD. Further studies are required to validate this novel score to assess PPBoD in CD.
P542 Clinical decision support tool guided selective intensive induction strategy of ustekinumab in patients with Crohn’s disease: real-world evidence
Authors: Li Q , Tang J , Shi L , Lv X , Chen W , Guo Q , Li M , Gao X , Chao K
Published: January 2024

Background

Clinical decision support tool (CDST) of ustekinumab (UST) can predict the possibility of drug response1. However, the potential benefits of initial intensification induction therapy (IIT) to improve clinical outcomes for different responders has not been explored2. We aimed to evaluate the effectiveness and safety of the strategy of initial IIT for Crohn’s disease patients who exhibit varying responses based on UST-CDST.

Methods

This is a multicenter retrospective study included active Crohn’s disease patients who were low, intermediate and high probability responders according to UST-CDST (Figure 1). IIT was defined as intensive induction by 2 or 3 initial doses of a weight-based intravenous UST. The patients treated with standard therapy (ST) were identified as controls. The primary endpoint was corticosteroid-free clinical remission (CFCR) at week 24. The secondary endpoint was clinical remission, clinical response, endoscopic remission, endoscopic response, and CRP normalization at week 24. Propensity-matched analyses were applied to ensure comparability.

Results

A total of 296 patients were included, with 69 patients receiving IIT and 227 patients receiving ST. At week 24, in low-intermediate probability responders, IIT group was associated with higher rates of CFCR (72.3% vs 43.0%, OR 3.47 [95%CI 2.15-5.68], clinical remission (77.3% vs 47.1%, OR 3.82 [95%CI 2.33-6.37]), clinical response (78.1% vs 60.1%, OR 2.37 [95%CI 1.43-3.97]), endoscopic remission (50.6% vs 22.4%, OR 3.55 [95%CI 1.65-7.92]) and endoscopic response (83.1% vs 44.1%, OR 6.23 [95%CI 2.75-15.26]). CRP normalization were comparable. In high probability responders, all end points did not demonstrate statistically significant differences (Table 1). The cut-off UST trough concentration for predicting corticosteroid-free clinical remission was determined to be 1.43µg/mL, with an area under the curve (AUC) of 0.612, a sensitivity of 55.0%, and a specificity of 70.0%. No serious adverse events occurred.

Conclusion

Initial dose intensification induction in low-intermediate responders based on UST-CDST was superior to the ST in both clinical and endoscopic remission at week 24, which provide a novel strategy for stratifying patients at baseline.

1. Park J, Chun J, Yoon H, Cheon JH. Feasibility of a Clinical Decision Support Tool for Ustekinumab to Predict Clinical Remission and Relapse in Patients With Crohn's Disease: A Multicenter Observational Study. Inflamm Bowel Dis. 2023;29(4):548-554.

2. Ren H, Kang J, Wang J, et al. Efficacy of Ustekinumab Optimization by 2 Initial Intravenous Doses in Adult Patients With Severe Crohn's Disease [published online ahead of print, 2023 Aug 24]. Inflamm Bowel Dis. 2023; izad184.