Evolving role of endoscopy in inflammatory bowel disease: Going beyond diagnosis

The ulcerative colitis endoscopic index of severity score is superior to reflecting long-term prognosis in ulcerative colitis patients treated with vedolizumab

The scoring systems commonly used to assess endoscopic disease severity of ulcerative colitis (UC) in clinical research and practice include the Mayo endoscopic score (MES), ulcerative colitis endoscopic severity index (UCEIS), and degree of ulcerative colitis burden of luminal inflammation (DUBLIN). We aimed to assess and compare the predictive efficacy of the MES, DUBLIN score and UCEIS score for prognosis in UC patients treated with vedolizumab (VDZ). Seventy-four UC patients who treated with VDZ from September 2021 to February 2023 were retrospectively enrolled. We used the MES, DUBLIN and UCEIS score to evaluate endoscopic findings. The predictive capability of these 3 scores for surgery or therapeutic escalation was assessed using the receiver operating characteristic curve. The mean MES, DUBLIN and UCEIS score significantly improved from 2.83 ± 0.38, 7.80 ± 1.82 and 6.24 ± 1.51 to 2.07 ± 0.88, 5.57 ± 2.68, and 3.72 ± 2.12, respectively (P < .001). Lower pre-therapeutic UCEIS scores were associated with favorable short-term outcomes. Importantly, the post-therapeutic UCEIS score showed the best predictive capability with an area under curve of 0.871 (95% confidence interval: 0.767-0.976), specificity of 0.654, sensitivity of 0.900, and cutoff value of 3.5. A UCEIS score of ≥ 4 after treatment was correlated with surgical operation or treatment escalation. The UCEIS score is superior to the MES and DUBLIN score in reflecting short-term outcomes and long-term prognosis in UC patients treated with VDZ, and clinical remission could be defined as a UCEIS score ≤ 3.

Serum long noncoding RNA H19/micro RNA-675-5p axis as a probable diagnostic biomarker in inflammatory bowel disease

BACKGROUND

A significant body of research strengthens the starring role of long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) in the pathogenesis of inflammatory bowel disease (IBD). Here, we investigated the diagnostic utility of lncRNA H19 and miRNA-675-5p in IBD.

METHODS

This study included 97 participants, thirty-five ulcerative colitis patients, thirty-two Crohn's disease patients, and thirty IBD-free controls. History, staging, laboratory investigations, and colonoscopy were performed. Also, quantitative real-time PCR (qPCR) for revealing of lncRNA H19 and miRNA-675-5p was done.

RESULTS

The estimated serum levels for H19 and miRNA-675-5p in the UC and CD groups in comparison to the control group showed a high statistical difference (P = 0.0001 for each parameter). Based upon the severity of UC patients, both biomarkers showed significantly higher values between remission and moderate cases, with p-values 0.022 and 0.02, respectively. Meanwhile, in CD patients, both biomarkers revealed no statistical significance between remission and any active stage of the disease. Additionally, ROC analysis revealed that H19 could discriminate between UC and control subjects with 94.3% sensitivity and 90.0% specificity, and with 87.5% sensitivity, and 88.5% specificity in the CD group. Furthermore, miR-675-5p was able to discriminate between UC and control subjects with 85.7% sensitivity and 97.3% specificity and with 88.4% sensitivity, 95.2% specificity in the CD group. Logistic regression found a significant predictive utility of using miR-675-5p and H19 in IBD.

CONCLUSION

H19 and miRNA-675-5p can be used as diagnostic biomarkers in IBD, with superiority in UC patients with moderate activity.

Review article: Translating STRIDE-II into clinical reality - Opportunities and challenges

BACKGROUND

With the introduction of novel therapies for inflammatory bowel diseases (IBD), 'treat-to-target' strategies are increasingly discussed to improve short- and long-term outcomes in patients with IBD.

AIM

To discuss opportunities and challenges of a treat-to-target approach in light of the current 'Selecting Therapeutic Targets in Inflammatory Bowel Disease' (STRIDE-II) consensus METHODS: The 2021 update of STRIDE-II encompasses 13 evidence- and consensus-based recommendations for treat-to-target strategies in adults and children with IBD. We highlight the potential implications and limitations of these recommendations for clinical practice.

RESULTS

STRIDE-II provides valuable guidance for personalised IBD management. It reflects scientific progress as well as increased evidence of improved outcomes when more ambitious treatment goals such as mucosal healing are achieved.

CONCLUSIONS

Prospective studies, objective criteria for risk stratification, and better predictors of therapeutic response are needed to potentially render 'treating to target' more effective in the future.

CD73 blockade alleviates intestinal inflammatory responses by regulating macrophage differentiation in ulcerative colitis

Ulcerative colitis (UC) is a type of inflammatory bowel disease characterized by excessive and persistent inflammation. Intestinal macrophages play a considerable role in regulating inflammatory immune reactions in the gut mucosa. It has previously been reported that CD73 is related to the pathogenesis of inflammatory or immune-related diseases; however, the roles of CD73 in UC remain unclear. In this study, CD73 expression in the inflamed mucosa of patients with UC was examined using reverse transcription-quantitative PCR (RT-qPCR), western blotting, and immunohistochemistry. Adenosine 5'-(α, β-methylene) diphosphate (APCP) was used to block the expression of CD73. Furthermore, the mRNA levels of proinflammatory mediators associated with macrophages following the blocking of CD73 were examined using RT-qPCR. Finally, the regulatory function of CD73 in intestinal inflammation was assessed by administering APCP in a mouse model of dextran sulfate sodium salt (DSS)-induced colitis. Notably, it was found that CD73 expression was significantly increased in the colonic mucosal tissues of patients with UC. Blockade of CD73 inhibited the expression of pro-inflammatory cytokines but promoted the production of anti-inflammatory cytokines in macrophages, while its promotion of M2 macrophage polarization was also verified. In vivo, CD73 blockade markedly alleviated DSS-induced colitis in mice, as characterized by reduced weight loss, reduction in the incidence of diarrhea, and reduced amount of bloody stool. Mechanistically, it was shown that CD73 regulated macrophage differentiation via the NF-κB and ERK signaling pathways. In conclusion, the findings of the present study indicate that CD73 may have a potential impact on the pathogenesis of UC by modulating the immune response of macrophage differentiation; thus, providing a novel pathway for modulating mucosal inflammation in UC.

Impaired Intestinal Permeability Assessed by Confocal Laser Endomicroscopy-A New Potential Therapeutic Target in Inflammatory Bowel Disease

Inflammatory bowel diseases (IBD) represent a global phenomenon, with a continuously rising prevalence. The strategies concerning IBD management are progressing from clinical monitorization to a targeted approach, and current therapies strive to reduce microscopic mucosal inflammation and stimulate repair of the epithelial barrier function. Intestinal permeability has recently been receiving increased attention, as evidence suggests that it could be related to disease activity in IBD. However, most investigations do not successfully provide adequate information regarding the morphological integrity of the intestinal barrier. In this review, we discuss the advantages of confocal laser endomicroscopy (CLE), which allows in vivo visualization of histological abnormalities and targeted optical biopsies in the setting of IBD. Additionally, CLE has been used to assess vascular permeability and epithelial barrier function that could correlate with prolonged clinical remission, increased resection-free survival, and lower hospitalization rates. Moreover, the dynamic evaluation of the functional characteristics of the intestinal barrier presents an advantage over the endoscopic examination as it has the potential to select patients at risk of relapses. Along with mucosal healing, histological or transmural remission, the recovery of the intestinal barrier function emerges as a possible target that could be included in the future therapeutic strategies for IBD.

Development of a Convolutional Neural Network-Based Colonoscopy Image Assessment Model for Differentiating Crohn’s Disease and Ulcerative Colitis

Objective

Evaluation of the endoscopic features of Crohn’s disease (CD) and ulcerative colitis (UC) is the key diagnostic approach in distinguishing these two diseases. However, making diagnostic differentiation of endoscopic images requires precise interpretation by experienced clinicians, which remains a challenge to date. Therefore, this study aimed to establish a convolutional neural network (CNN)-based model to facilitate the diagnostic classification among CD, UC, and healthy controls based on colonoscopy images.

Methods

A total of 15,330 eligible colonoscopy images from 217 CD patients, 279 UC patients, and 100 healthy subjects recorded in the endoscopic database of Tongji Hospital were retrospectively collected. After selecting the ResNeXt-101 network, it was trained to classify endoscopic images either as CD, UC, or normal. We assessed its performance by comparing the per-image and per-patient parameters of the classification task with that of the six clinicians of different seniority.

Results

In per-image analysis, ResNeXt-101 achieved an overall accuracy of 92.04% for the three-category classification task, which was higher than that of the six clinicians (90.67, 78.33, 86.08, 73.66, 58.30, and 86.21%, respectively). ResNeXt-101 also showed higher differential diagnosis accuracy compared with the best performing clinician (CD 92.39 vs. 91.70%; UC 93.35 vs. 92.39%; normal 98.35 vs. 97.26%). In per-patient analysis, the overall accuracy of the CNN model was 90.91%, compared with 93.94, 78.79, 83.33, 59.09, 56.06, and 90.91% of the clinicians, respectively.

Conclusion

The ResNeXt-101 model, established in our study, performed superior to most clinicians in classifying the colonoscopy images as CD, UC, or healthy subjects, suggesting its potential applications in clinical settings.