Treat to target in Crohn’s disease: A practical guide for clinicians

A patient-reported outcome measure comprising the stool frequency and abdominal pain items from the Crohn's Disease Activity Index: psychometric evaluation in adults with Crohn's disease

BACKGROUND

The Stool Frequency (SF) and Abdominal Pain (AP) items from the Crohn's Disease Activity Index are together referred to as the "Patient Reported Outcome" (PRO). The SF item measures the number of very soft/liquid stools and the AP item measures abdominal pain severity, which are common Crohn's disease (CD) symptoms that patients consider important to treat. This study evaluated the psychometric properties of both PRO items separately and estimated thresholds for clinical remission in moderately to severely active CD.

METHODS

The measurement properties of the PRO items were analyzed using pooled data from VIVID-1 (NCT03926130), a Phase 3, randomized, placebo- and active-controlled study in adults with moderately to severely active CD. Analyses used weekly average scores of the SF and AP items at Weeks 0 (Baseline), 4, 12, and 52. Remission thresholds were estimated using the Patient Global Rating of Severity (PGRS) and Patient Global Impression of Change (PGIC) as primary anchors as well as qualitative evidence from exit interviews.

RESULTS

Data from 1065 participants (mean age: 36.2 years [standard deviation: 13 years]) were analyzed. During the trial, scores improved for both PRO items. Both items demonstrated moderate-to-good test-retest reliability for participants defined as stable based on PGRS and PGIC. Most correlations of related assessments were moderate (0.30≤|ρ| <0.70) with SF and moderate-to-large (0.30≤|ρ| ≤0.90) with AP. By contrast, as anticipated, both items had weak correlations (|ρ| <0.30) with endoscopic and laboratory assessments. The PRO items could discriminate between groups of participants known to differ based on other assessments. The PRO items were able to detect change, as score changes in both items between Baseline and Weeks 12 and 52 differed significantly between most PGRS and PGIC categories. Anchor-based analyses combined with responses from the exit interviews suggested that an SF score of ≤ 3 and an AP score of ≤ 1 could together represent clinical remission.

CONCLUSION

These results support the reliability, construct-validity, and responsiveness of both PRO items in moderately to severely active CD and confirm previously suggested scores for both items that could represent clinical remission.

TRIAL REGISTRATION

Clinicaltrials.gov, NCT03926130. Registered 23 April 2019, https://clinicaltrials.gov/study/NCT03926130 .

Assessment of the Utility of Selected Inflammatory Markers in Correlation with Magnetic Resonance Enterography (MRE) Findings in the Diagnosis of Crohn's Disease

Crohn's Disease (CD) is a chronic inflammatory bowel disease affecting the gastrointestinal tract. The search continues for new markers for assessing the activity of CD. Among them, pro-inflammatory and anti-inflammatory cytokines appear promising. We performed the analysis of cytokine concentrations in blood serum using the Bio-Plex Multiplex system (Bio-Rad), and their correlations with radiological parameters were assessed by magnetic resonance enterography (MRE), and fecal calprotectin levels were measured quantitatively by ELISA and clinical evaluation according to the Crohn's Disease Activity Index (CDAI). Our study found that measuring cytokine serum concentrations can be a valuable tool in the diagnosis and treatment of CD. Positive correlations were reported between contrast enhancement on DCE-MRE and the concentrations of PDGF-BB and RANTES. Also, a positive correlation was found between the delayed-phase of DCE and IL-10 concentration, a strong negative correlation between the delayed-phase of DCE and IL-12 concentration, and a strong positive correlation between the delayed-phase of DCE and RANTES concentrations. A strong positive correlation was also observed between the thickness of the intestinal wall on T2-weighted images and RANTES concentration. Therefore, concentrations of PDGF-BB, RANTES, IL-10 and IL-12 are promising markers of CD activity. The study also demonstrated significant correlations between the severity of disease activity assessed by the CDAI and the concentrations of IL-5, IL-8 and IL-9, as well as positive correlations between the levels of fecal calprotectin and the concentrations of IL-1RA and VEGF. Therefore, the levels of IL-5, IL-8, IL-9, VEGF and IL-1RA may be useful markers in the diagnosis and clinical assessment of disease activity.

C-X-C Motif Chemokine 12 Was Identified as a Potential Gene Target in the Treatment of Crohn's Disease

Object

The present study aimed to identify hub genes associated with the treatment and control of active and inactive Crohn's disease (CD).

Methods

Differentially expressed genes (DEGs) were identified in normal, active CD, and inactive CD samples from GSE95095 dataset. Intersection genes screened by Venn diagram in DEGs. Subsequently, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were conducted on the intersection genes. The protein-protein interaction (PPI) network was used to screen of hub gene. The expression and mRNA levels of CXCL12 in CD and ROC curves in GSE95095 dataset. Signaling pathways of hub genes and their correlation with immune cells were analyzed by gene set enrichment analysis (GSEA), EPIC, and ESTIMATE, respectively. Finally, immunohistochemistry (IHC) and Reverse Transcription-Polymerase Chain Reaction (RT-PCR) were used to detect the expression of the hub gene in normal, inactive, and active CD tissues.

Results

In GSE95095 dataset, CXCL12 was identified as the most hub gene by limma analysis, Venn diagram and A protein-protein interaction (PPI) network. CXCL12 expression was highest in active CD (p < 0.001) followed by inactive CD (p < 0.01). Subsequently, it was validated through IHC and RT-PCR in normal intestinal mucosal, active CD, and inactive CD. CXCL12 was overexpressed in active and inactive CD (IHC: p < 0.001 and RT-PCR: p < 0.001, respectively). CXCL12 expression in active CD was determined via analysis with receiver operating characteristic (ROC) curves. The specificity and sensitivity were 0.875 and 0.625, respectively, the accuracy was 72.92%, the area under the curve (AUC) was 0.780, and the 95% confidence interval (CI) was in the range of 0.648-0.912. CXCL12 expression was closely correlated with various immune cells.

Conclusion

CXCL12 is overexpressed in active CD and is closely correlated with various immune cells. We propose that CXCL12 as a potential target genes for the treatment and management of both active and inactive CD.

Anti-VEGF therapy for the long-term management of diabetic macular edema: a treat-to-target strategy based on macular morphology

In an aging population, the prevalence and burden of diabetes mellitus, diabetic retinopathy, and vision-threatening diabetic macular edema (DME) are only expected to rise around the world. Similarly to other complications of diabetes mellitus, DME requires long-term management. This article aims to review the current challenges associated with the long-term management of DME, opportunities to improve outcomes for patients, and to develop a treat-to-target strategy based on macular morphology. At present, intravitreal anti-vascular endothelial growth factor (VEGF) therapy is the standard of care for the management of DME; however, best-achievable vision outcomes with treatment are reliant on frequent injections and close monitoring, which are difficult to maintain in current clinical practice because of the burden this imposes on patients. Achieving and maintaining good vision with treatment are the most important factors for patients with DME. Landmark trials have shown that vision gains with anti-VEGF therapy are typically accompanied by anatomical improvements (e.g., reductions in retinal thickness); therefore, multimodal imaging measures of macular morphology are often used in patients with DME to guide real-world treatment decisions. We would like to propose a hypothetical treat-to-target algorithm to guide physicians on treatment strategies for the long-term management of DME. Alternative measures of retinal fluid (e.g., persistence, stability, location) may be stronger predictors of visual acuity in DME, although further research is required to confirm whether alternate quantifiable biomarkers such as subretinal fluid and intraretinal fluid volumes can be used as a biomarker of clinical improvement. Identifying novel biomarkers and treatments that target neuroinflammation and neurodegeneration, improving patient-physician communication around treatment adherence, and using treat-to-target measures may help to ensure that the long-term benefits of treatment are realized.

Navigating new horizons in inflammatory bowel disease: Integrative approaches and innovations

This editorial offers an updated synthesis of the major advancements in the management and treatment of inflammatory bowel disease (IBD), as documented in the World Journal of Gastroenterology between 2023 and early 2024. This editorial explores substantial developments across key research areas, such as intestinal microecology, computational drug discovery, dual biologic therapy, telemedicine, and the integration of lifestyle changes into patient care. Furthermore, the discussion of emerging topics, including bowel preparation in colonoscopy, the impact of the coronavirus disease 2019 pandemic, and the intersection between IBD and mental health, reflects a shift toward a more holistic approach to IBD research. By integrating these diverse areas of research, this editorial seeks to promote a holistic and multidisciplinary approach to IBD treatment, combining emerging technologies, personalized medicine, and conventional therapies to improve patient outcomes.

Artificial Intelligence in Coloproctology: A Review of Emerging Technologies and Clinical Applications

Artificial intelligence (AI) has emerged as a transformative tool across several specialties, namely gastroenterology, where it has the potential to optimize both diagnosis and treatment as well as enhance patient care. Coloproctology, due to its highly prevalent pathologies and tremendous potential to cause significant mortality and morbidity, has drawn a lot of attention regarding AI applications. In fact, its application has yielded impressive outcomes in various domains, colonoscopy being one prominent example, where it aids in the detection of polyps and early signs of colorectal cancer with high accuracy and efficiency. With a less explored path but equivalent promise, AI-powered capsule endoscopy ensures accurate and time-efficient video readings, already detecting a wide spectrum of anomalies. High-resolution anoscopy is an area that has been growing in interest in recent years, with efforts being made to integrate AI. There are other areas, such as functional studies, that are currently in the early stages, but evidence is expected to emerge soon. According to the current state of research, AI is anticipated to empower gastroenterologists in the decision-making process, paving the way for a more precise approach to diagnosing and treating patients. This review aims to provide the state-of-the-art use of AI in coloproctology while also reflecting on future directions and perspectives.

A Comprehensive Review of Artificial Intelligence and Colon Capsule Endoscopy: Opportunities and Challenges

Colon capsule endoscopy (CCE) enables a comprehensive, non-invasive, and painless evaluation of the colon, although it still has limited indications. The lengthy reading times hinder its wider implementation, a drawback that could potentially be overcome through the integration of artificial intelligence (AI) models. Studies employing AI, particularly convolutional neural networks (CNNs), demonstrate great promise in using CCE as a viable option for detecting certain diseases and alterations in the colon, compared to other methods like colonoscopy. Additionally, employing AI models in CCE could pave the way for a minimally invasive panenteric or even panendoscopic solution. This review aims to provide a comprehensive summary of the current state-of-the-art of AI in CCE while also addressing the challenges, both technical and ethical, associated with broadening indications for AI-powered CCE. Additionally, it also gives a brief reflection of the potential environmental advantages of using this method compared to alternative ones.

Treatment Targets Should Influence Choice of Infliximab Dose Intensification Strategy in Inflammatory Bowel Disease: A Pharmacokinetic Simulation Study

BACKGROUND

The optimal infliximab dose intensification strategy to address loss of response associated with subtherapeutic infliximab trough levels remains uncertain, as does whether post-intensification trough and treatment targets should influence this decision.

OBJECTIVES

This pharmacokinetic simulation study aimed to identify infliximab dose intensification strategies capable of achieving post-intensification infliximab trough thresholds associated with clinical and objective treatment targets in Crohn's disease and ulcerative colitis.

METHODS

A validated pharmacokinetic infliximab model, applied to 200 simulated patients, identified those with subtherapeutic (< 3.00 mg/L) trough levels after 30 weeks of standard (5 mg/kg 8-weekly) dosing, and subsequently applied 10 dose intensification strategies over a further 32 weeks. The proportion of simulations achieving 32-week post-intensification infliximab trough levels associated with endoscopic remission (ulcerative colitis > 7.50 mg/L, Crohn's disease > 9.70 mg/L) was the primary outcome, with perianal fistula healing (Crohn's disease > 10.10 mg/L) and clinical improvement (ulcerative colitis > 3.70 mg/L, Crohn's disease > 7.00mg/L) evaluated as secondary outcomes. All outcomes were stratified by intensity of dose intensification, with standard (≤ 10 mg/kg 8-weekly or 5 mg/kg 4-weekly; n = 5) and intensive (> 10 mg/kg 8-weekly or 5 mg/kg 4-weekly; n = 5) dosing strategies defined, respectively.

RESULTS

The median pre-intensification infliximab trough level was 0.91 mg/L (interquartile range 1.37). Intensive dosing strategies were more likely to achieve infliximab trough concentrations associated with endoscopic remission (ulcerative colitis 36.48% vs. 10.80%, Crohn's disease 25.98 vs. 4.68%), perianal fistula healing (24.52% vs. 4.36%) and clinical improvement (ulcerative colitis 61.90% vs. 34.86%, Crohn's disease 40.32 vs. 12.08%) than standard intensification strategies (all p < 0.01). When controlling for cumulative (mg/kg) infliximab dose over 32 weeks, strategies that concurrently dose increased and interval shortened achieved the highest infliximab trough levels (all p < 0.01).

CONCLUSION

This simulation-based analysis highlights the potential of using post-intensification infliximab trough thresholds associated with aspirational treatment targets in Crohn's disease and ulcerative colitis to guide choice of infliximab dose intensification strategy. Intensive dose intensification strategies, particularly those that concurrently dose increase and interval shorten, appear to achieve higher infliximab levels than standard dose intensification strategies. This may be particularly important in the pursuit of stringent endpoints, such as endoscopic remission and fistula healing, which have been consistently associated with higher infliximab trough levels. These findings require validation across real-world cohorts.

Eosinophils, Eosinophilic Gastrointestinal Diseases, and Inflammatory Bowel Disease: A Critical Review

BACKGROUND/OBJECTIVES

Inflammatory bowel disease (IBD) and eosinophilic gastrointestinal diseases (EGIDs) are complex, multifactorial chronic inflammatory disorders affecting the gastrointestinal tract. Their epidemiology, particularly for eosinophilic esophagitis (EoE), is increasing worldwide, with a rise in the co-diagnosis of IBD and EGIDs. Both disorders share common risk factors, such as early exposure to antibiotics or specific dietary habits. Moreover, from a molecular perspective, eosinophilic infiltration is crucial in the diagnosis of eosinophilic disorders, and it also plays a pivotal role in IBD histological diagnosis. Indeed, recent evidence highlights the significant role of eosinophils in the health of the intestinal mucosal barrier and as mediators between innate and acquired immunity, even indicating a potential role in IBD pathogenesis. This narrative review aims to summarize the current evidence regarding the common clinical and molecular aspects of EGIDs and IBD and the current state of knowledge regarding overlap conditions and their pathogenesis.

METHODS

Pubmed was searched until May 2023 to assess relevant studies describing the epidemiology, pathophysiology, and therapy of EGIDs in IBD.

RESULTS

The immune pathways and mechanisms underlying both EGIDs and IBD remain partially known. An improved understanding of the role of eosinophils in overlapping conditions could lead to enhanced diagnostic precision, the development of more effective future therapeutic strategies, and a more accurate prediction of patient response. Consequently, the identification of red flags indicative of an eosinophilic disorder in IBD patients is of paramount importance and must be evaluated on a case-by-case basis.