Ulcerative colitis: Impact of early disease clearance on long‐term outcomes ‐ A multicenter cohort study

Disease Clearance in Ulcerative Colitis: A Narrative Review

Ulcerative colitis (UC) is a chronic relapsing disease with significant associated risks such as colectomy, hospitalization, or colorectal cancer. A treat-to-target approach that mitigates disease activity and progression from an early stage is needed. The latest STRIDE II guidelines advocate for clinical and endoscopic remission as the main therapeutic targets in the management of UC; however, histological remission is increasingly being recognized as an important outcome. The concept of disease clearance, a composite outcome comprising clinical, endoscopic, and histological remission, has been proposed as a potential target for patients with UC and has been precisely defined by the International Organization for the Study of Inflammatory Bowel Disease, with the aim of standardizing its use in clinical practice and research. Despite challenges, including variable standardized definitions and uncertainties regarding the timing of reaching different definitions of remission, disease clearance corresponds to comprehensive disease control, and its use as an outcome could help clinicians to better evaluate the actual status of the disease. Furthermore, achieving disease clearance may be related to an improved disease course, positive long-term outcomes, and an improvement in health-related quality of life. Real-world evidence supports the feasibility of achieving disease clearance with various treatment modalities, including vedolizumab, the only gut-selective antilymphocyte trafficking drug. The aim of this narrative review is to explore the concept of disease clearance in patients with disease clearance, mainly focusing on trials evaluating vedolizumab but also other biologics.

Novel outcomes in inflammatory bowel disease

Inflammatory bowel diseases (IBD), Crohn's disease (CD), and ulcerative colitis (UC) are lifelong chronic, relapsing, and remitting conditions that culminate in disease progression in many patients. Effective management of CD and UC requires consideration of both short- and long-term treatment outcomes. Historically, short-term outcomes such as clinical and endoscopic remission and symptom relief have been evaluated in clinical trials. With the expansion of treatments targeting underlying disease pathophysiology, there is the opportunity to develop management strategies that improve disease control and patients' lives in both the short and the long term. Researchers have been examining novel outcomes for assessing the efficacy of CD and UC treatments that are important to patients, and also those that go beyond symptomatic improvements or clinical remission. These include new patient-reported outcomes for symptoms, as well as transmural/histological healing and disease clearance that can be more reflective of deeper remission states and disease modification. This review analyses published clinical studies involving patients with UC and CD treated with biologics or small molecule therapies. It highlights novel IBD endpoints employed in published clinical trials and discusses their likely value for assessing disease activity and disease modification, and as predictors of reduced risk of complications and morbidities.

Endoscopic, Histologic, and Composite Endpoints in Patients With Ulcerative Colitis Treated With Etrasimod

BACKGROUND & AIMS

Histologic remission, a potentially important treatment target in ulcerative colitis (UC), is associated with favorable long-term outcomes. Etrasimod is an oral, once-daily, selective sphingosine 1-phosphate (S1P)1,4,5 receptor modulator for the treatment of moderately to severely active UC. This post-hoc analysis of the ELEVATE UC program evaluated the efficacy of etrasimod according to histologic and composite (histologic/endoscopic/symptomatic) endpoints and examined their prognostic value.

METHODS

Patients with moderately to severely active UC were randomized 2:1 to once-daily oral etrasimod 2 mg or placebo. Histologic and composite endpoints, including disease clearance (endoscopic/histologic/symptomatic remission), were assessed at Weeks 12 (ELEVATE UC 52; ELEVATE UC 12) and 52 (ELEVATE UC 52). Logistic regressions examined associations between baseline and Week 12 histologic/composite endpoints and Week 52 outcomes.

RESULTS

At Weeks 12 and 52, significant improvements with etrasimod vs placebo were observed in histologic/composite outcomes, including endoscopic improvement-histologic remission and disease clearance. The proportion of patients treated with etrasimod achieving clinical remission at Week 52 was higher among those with disease clearance at Week 12 vs those without disease clearance (73.9% [17/23] vs 28.3% [71/251]). Histologic improvement and endoscopic improvement at Week 12 were moderately and strongly associated with clinical remission at Week 52 (odds ratio [OR], 2.37; 95% confidence interval [CI], 1.27-4.41; and OR, 6.36; 95% CI, 3.47-11.64, respectively). Histologic remission and endoscopic improvement at Week 12 were strongly associated with endoscopic improvement-histologic remission at Week 52 (OR, 3.21; 95% CI, 1.70-6.06 and OR, 5.47; 95% CI, 2.89-10.36, respectively).

CONCLUSIONS

Etrasimod was superior to placebo for achievement of stringent histologic and composite endpoints.

CLINICALTRIALS

gov, Number: NCT03945188; ClinicalTrials.gov, Number: NCT03996369.

Advancing Therapeutic Targets in IBD: Emerging Goals and Precision Medicine Approaches

Inflammatory bowel diseases (IBD) including Crohn's disease (CD) and ulcerative colitis (UC) are chronic, relapsing conditions characterized by dysregulated immune responses and persistent intestinal inflammation. This review aims to examine new potential therapeutic targets in IBD starting from the STRIDE-II statements. Key targets now include clinical remission, endoscopic remission, and biomarker normalization (such as C-reactive protein and fecal calprotectin). Moreover, histologic remission, transmural remission, and in the future molecular targets are emerging as important indicators of sustained disease control. The treatment goals for inflammatory bowel disease are varied: to relieve symptoms, prevent permanent intestinal damage, promote inflammation remission, and minimize complications. Consequently, the therapeutic targets have evolved to become broader and more ambitious. Integrating these advanced therapeutic targets has the potential to redefine IBD management by promoting deeper disease control and improved patient outcomes. Further research is essential to validate these strategies and optimize their clinical implementation.

Dual Biologic Therapy Induces Remission in Refractory Crohn's Disease With Vedolizumab and Ustekinumab

Background

Despite advancements in the therapeutic armamentarium for Crohn's disease (CD), biologic and small molecule monotherapies are associated with sub-optimal response and remission rates. Utilizing dual biologic therapy (DBT) holds the potential to increase efficacy in the treatment of refractory or partially responsive CD. Evidence pertaining to this strategy remains limited.

Methods

We retrospectively examined refractory CD patients treated with a combination of ustekinumab and vedolizumab. Outcomes to DBT at week (wk) 52 were compared to monotherapy. The primary outcome constituted corticosteroid-free remission. Secondary outcomes included adverse events, infections, hospitalizations, surgeries, treatment persistence, and disease clearance.

Results

Sixteen of 21 active refractory CD patients (76%) on DBT achieved disease remission at wk 52. Mucosal healing was observed in 38% (n = 6), biochemical remission in 25% (n = 4), and both clinical and biochemical remission in 38% (n = 6). Of these patients, 50% (n = 8) achieved corticosteroid-free remission. Three patients (37.5%) with corticosteroid-free remission achieved complete disease clearance. Paired median fecal calprotectin decreased from 508 to 118 µg/g (P < .0001). Paired C-reactive protein median decreased from 1.04 to 0.50 mg/dL (P < .0001). Median Harvey Bradshaw Index score reduced from 7 to 2 (P = .003). Endoscopic healing was achieved with a paired simple endoscopic score for CD decrease from 6 to 3 (P = .013). Corticosteroid dependency reduced from 17 to 8 patients discontinuing altogether. Patients still requiring corticosteroids experienced a decrease in average daily dose from 9 to 6 mg (P = .045). At wk 52, 5 patients (24%) did not meet the criteria for remission with 4 requiring CD-related surgical intervention. Mean CD-related hospitalizations reduced from 2.95 ± 2.33 to 0.52 ± 1.12 (P < .001) and surgeries from 1.76 ± 1.3 to 0.14 ± 0.4 (P < .001). Three infections with 1 requiring hospitalization and 1 report of headache were noted. Two patients discontinued DBT.

Conclusions

Dual biologic therapy with ustekinumab and vedolizumab is a safe and effective strategy to induce disease remission in refractory CD. Large-scale studies are necessary to validate findings in a prospective setting.

Raising the bar in ulcerative colitis management

Ulcerative colitis (UC) is a chronic inflammatory bowel disease characterized by growing incidence and prevalence around the world in the last few decades. The range of available existing treatment and strategies for its management is being implemented. Given the introduction of newly developed molecules and the lack of specific guidelines, drug positioning may represent a tough clinical challenge. UC management is mostly medical, and it has been shifting toward a more personalized approach with the aim to create a tailored strategy depending on the patient's profile. A treat-to target strategy seems to be the best approach to reach disease control as it allows to carry out therapeutic choices based on objective and specific parameters: histological, ultrasonographic, and molecular targets may add to the already used clinical, endoscopic, and biochemical targets. In addition, dual-targeted therapy has emerged as an attractive therapeutic strategy for patients not achieving remission. This review aims to provide an overview of the available strategies to raise the bar in UC.

An artificial intelligence-driven scoring system to measure histological disease activity in ulcerative colitis

BACKGROUND AND AIMS

Assessment and scoring of histological images in Ulcerative colitis (UC) is prone to inter- and intra-observer variability. This study aimed to investigate whether an artificial intelligence (AI) system developed using image processing and machine learning algorithms could measure histological disease activity based on the Nancy index.

METHODS

A total of 200 histological images of patients with UC were used in this study. A novel AI algorithm was developed using state-of-the-art image processing and machine learning algorithms based on deep learning and feature extraction. The cell regions of each image, followed by the Nancy index, were manually annotated and measured independently by four histopathologists. Manual and AI-automated measurements of the Nancy index score were conducted and assessed using the intraclass correlation coefficient (ICC).

RESULTS

The 200-image dataset was divided into two groups (80% was used for training and 20% for testing). Intraclass correlation coefficient statistical analyses were performed to evaluate the AI tool and used as a reference to calculate the accuracy. The average ICC among the histopathologists was 89.3 and the average ICC between histopathologists and the AI tool was 87.2. The AI tool was found to be highly correlated with histopathologists.

CONCLUSIONS

The high correlation of performance of the AI method suggests promising potential for inflammatory bowel disease clinical applications. A standardized automated histological AI-driven scoring system can potentially be used in daily inflammatory bowel disease practice to reduce training needs and resource use, eliminate the subjectivity of the pathologists, and assess disease severity for treatment decisions.

To STRIDE or not to STRIDE: a critique of "treat to target" in ulcerative colitis

INTRODUCTION

The STRIDE consensus intends to complement the clinical endpoint with an endoscopic endpoint of mucosal healing and others as treatment targets in ulcerative colitis. If these targets are not reached, STRIDE requires dose or timing adjustments or switching the medication. This narrative review provides a critique of this concept.

AREAS COVERED

We analyze and discuss the limitations of current endpoints as targets, their currently limited achievability, and the lacking evidence from controlled trials relating to 'treat to target.' The relevant publications in PubMed were identified in a literature review with the key word 'ulcerative colitis.'

EXPERT OPINION

In ulcerative colitis, the standard clinical target is measured traditionally by the MAYO-score, but in variable combinations of patient and physician reported outcomes as well as also different definitions of the endoscopic part. Only a score of 0 is more stringent than clinical remission but is only achieved by a minority of patients in first and even less in second line therapy. The concept is not based on clear evidence that patients indeed benefit from appropriate escalation of treatment. Until the STRIDE approach is proven to be superior to standard treatment focusing on clinical well-being, the field should remain reluctant.

Clinical Trial: A Pragmatic Randomised Controlled Study to Assess the Effectiveness of Two Patient Management Strategies in Mild to Moderate Ulcerative Colitis-The OPTIMISE Study

Background: Current management of mild-to-moderate ulcerative colitis (UC) involves monitoring clinical markers of disease activity, such as stool frequency (SF) and rectal bleeding (RB), and adjusting treatment accordingly. Our aim was to assess whether targeting treatment based on faecal calprotectin (FC) levels (treat-to-target; T2T) provides greater UC disease control versus a symptom-based approach. Methods: This was a pragmatic, randomised (1:1) controlled study of patients with mild-to-moderate UC (global Mayo score 2-6) treated with ≤2.4 g/day 5-aminosalicylic acid that compared the effectiveness of two management strategies with (interventional arm) and without (reference arm) FC home monitoring over 12 months of follow-up. Treatment was optimised in the interventional arm using FC values and clinical symptoms (PRO-2), while the reference arm used only PRO-2. Results: 193 patients completed the study. No significant difference was found for the primary endpoint (Mayo Endoscopic Subscore [MES] = 0 at 12 months). A numerical advantage for the interventional arm over the reference arm for the primary endpoint (37.0% vs. 33.4%, respectively) and for MES ≤ 1, RB = 0, and SF ≤ 1 at 12 months was found following imputation for missing data. The composite endpoint of MES = 0, RB = 0, and SF ≤ 1 at 12 months was achieved at a significantly higher rate in the interventional arm than the reference arm (effect size [ES]: 0.17, 95% CI 0.02-0.32; p < 0.05). A similar result was obtained for MES ≤ 1, RB = 0 and SF ≤ 1 (ES: 0.22; 95% CI 0.07-0.37; p < 0.05). Conclusions: T2T using FC monitoring was effective in patients with mild-to-moderate UC at 12 months. Further longer-term studies are required to confirm the results.

Deep mucosal healing in ulcerative colitis: how deep is better?

Ulcerative colitis (UC), characterized by its recurrent nature, imposes a significant disease burden and compromises the quality of life. Emerging evidence suggests that achieving clinical remission is not sufficient for long-term remission. In pursuit of a favorable prognosis, mucosal healing (MH) has been defined as the target of therapies in UC. This paradigm shift has given rise to the formulation of diverse endoscopic and histological scoring systems, providing distinct definitions for MH. Endoscopic remission (ER) has been widely employed in clinical practice, but it is susceptible to subjective factors related to endoscopists. And there's growing evidence that histological remission (HR) might be associated with a lower risk of disease flares, but the incorporation of HR as a routine therapeutic endpoint remains a debate. The integration of advanced technology has further enriched the definition of deep MH. Up to now, a universal standardized definition for deep MH in clinical practice is currently lacking. This review will focus on the definition of deep MH, from different dimensions, and analyze strengths and limitations, respectively. Subsequent multiple large-scale trials are needed to validate the concept of deep MH, offering valuable insights into potential benefits for UC patients.

Editorial: Mucosal healing with steroids: Once upon a time in ulcerative colitis

This article is linked to Fukuda et al papers. To view these articles, visit https://doi.org/10.1111/apt.18013 and https://doi.org/10.1111/apt.18111

Disease Clearance as a New Outcome in Ulcerative Colitis: a Systematic Review and Expert Consensus

The concept of disease clearance has been proposed as a potential target in ulcerative colitis (UC). We conducted a systematic review to investigate the role of disease clearance, defined as a composite outcome including simultaneous clinical, endoscopic, and histologic remission of disease in the management of patients with UC. Based on the literature data, statements regarding disease clearance were developed and voted on by the members of the International Organization for the Study of Inflammatory Bowel Diseases (IOIBD) according to a Delphi methodology. A definition of disease clearance was proposed to standardize its use in clinical practice and clinical trials and to provide practical recommendations for its implementation as a therapeutic target in UC.

Rapidly achieving clinical remission in ulcerative colitis indicates better endoscopic and histological outcomes

BACKGROUND

Clinical remission (CR) is the principal short-term treatment target in patients with ulcerative colitis (UC). However, whether rapidly achieving CR indicates better outcomes remains unclear.

OBJECTIVES

We aimed to explore the associations between the timing of CR and therapeutic outcomes in UC.

METHODS

This study included UC patients from the UNIFI trial. Week-2 CR and time to CR were the major variables of interest. Endoscopic remission (ER) at week 52 was the primary outcome. Multivariate logistic regression was performed to evaluate the association between variables and outcomes.

RESULTS

Week-2 CR was associated with ER (aOR: 2.37 [95% CI: 1.28, 4.37], p = 0.006) and Histological remission (HR) (aOR: 2.87 [95% CI: 1.42, 5.72], p = 0.003) at week 52. Moreover, C-reactive protein (CRP) remission could further stratify patients without CR and predict week-52 outcomes. Patients with clinical activity + CRP remission (aOR: 0.49 [95% CI: 0.26, 0.93], p = 0.039) and clinical activity + CRP activity (aOR: 0.24 [95% CI: 0.11, 0.52], p < 0.001) had gradually decreased likelihood of achieving ER, when compared to those with CR. For time to CR, we found that the earlier to CR, the better endoscopic and histological outcomes patients would attain. Patients achieving CR at weeks 2, 4/8, 12/16 and >16 had gradually reduced proportions of ER (51.9% vs. 40.8% vs. 31.6% vs. 8.8%, p < 0.001) and HR (37.0% vs. 19.8% vs. 17.1% vs. 6.1%, p < 0.001) at week 52. Compared with week 2, achieving CR at weeks 4/8, 12/16 and >16 had 39%, 55% and 92% lower likelihoods of week-52 ER, respectively.

CONCLUSIONS

Week-2 CR indicates better outcomes in UC patients receiving ustekinumab. Moreover, achieving CR more rapidly is associated with higher probability of ER and HR.

Disease clearance in ulcerative colitis: A new therapeutic target for the future

Advancements in murine modeling systems for ulcerative colitis have diversified our understanding of the pathophysiological factors involved in disease onset and progression. This has fueled the identification of molecular targets, resulting in a rapidly expanding therapeutic armamentarium. Subsequently, management strategies have evolved from symptomatic resolution to well-defined objective endpoints, including clinical remission, endoscopic remission and mucosal healing. While the incorporation of these assessment modalities has permitted targeted intervention in the context of a natural disease history and the prevention of complications, studies have consistently depicted discrepancies associated with ascertaining disease status through clinical and endoscopic measures. Current recommendations lack consideration of histological healing. The simultaneous achievement of clinical, endoscopic, and histologic remission has not been fully investigated. This has laid the groundwork for a novel therapeutic outcome termed disease clearance (DC). This article summarizes the concept of DC and its current evidence.

Comprehensive overview of novel chemical drugs for ulcerative colitis: focusing on phase 3 and beyond

INTRODUCTION

Despite the growing number of highly efficacious biologics and chemical drugs for ulcerative colitis (UC), steroid-free disease control is still difficult to achieve in subgroups of patients due to refractoriness, adverse events, primary or secondary failure. New treatments are therefore still required in order to optimize clinical management of patients with UC.

AREAS COVERED

The efficacy and safety of both currently available and newly developed small molecules have been summarized. The PubMed database and clinicaltrials.gov were considered in order to search for phase 2b and 3 trials on new chemical drugs for UC. The study drugs reviewed included Janus kinases (JAK) and sphingosine-1-phosphate receptor (S1Pr) inhibitors, α4 integrin antagonist, and micro-RNA-124 upregulators.

EXPERT OPINION

Rapidity of onset, low immunogenicity, and safety are the main characteristics of small molecules currently available or under evaluation for treatment patients with UC. Among the currently available chemical drugs, the selective JAK and the S1Pr inhibitors are characterized by a good safety profile combined with the ability to induce clinical remission in UC. A relatively low frequency of endoscopic improvement and healing currently appears associated with their use, being higher in UC patients treated with S1Pr inhibitor Etrasimod. Overall, additional new safe and effective drugs are still required in order to optimize disease control in a larger majority of UC patients.

Management and treatment optimization of patients with mild to moderate ulcerative colitis

INTRODUCTION

Ulcerative colitis (UC) is a chronic inflammatory bowel disease with a significant health-care burden worldwide. While medical therapy aims to induce and maintain remission, optimal management of mild to moderate UC remains challenging due to heterogeneity in severity classifications and non-standardized approaches. This comprehensive review summarizes current evidence and knowledge gaps to optimize clinical decision-making in patients with mild to moderate UC.

AREAS COVERED

After an extensive literature search of PubMed, Medline, and Embase through August 2023, we provide an overview of definitions utilized to characterize mild to moderate UC severity and established therapeutic targets. Current medical treatments including mesalazine formulations, corticosteroids, and their combinations are surveyed. The role of emerging intestinal ultrasound, telemedicine, and home testing is explored. Individualized, patient-centered paradigms aiming to streamline care delivery through proactive identification of relapses are also examined.

EXPERT OPINION

Addressing inconsistencies in disease activity stratification will better align tailored regimens with each patient's profile. Advancing noninvasive technologies like ultrasound criteria and home testing could improve UC management by enabling personalized models. Realizing individualized plans through informed shared-decision making between health-care providers and fully engaged patients holds promise to maximize quality of life outcomes. Continuous improvement relies on innovation bridging different domains to overcome current limitations and push the field toward more predictive and tailored care.

Evaluation of Disease Activity in Inflammatory Bowel Disease: Diagnostic Tools in the Assessment of Histological Healing

Inflammatory bowel disease (IBD) comprises two types of chronic intestinal disorders: Crohn's disease and ulcerative colitis. In long-standing ulcerative colitis disease activity, histological persistent inflammation has been linked to an increased risk of relapse, and long-term corticosteroid use, even when endoscopic remission is reached. In Crohn's disease, the discontinuous nature of lesions and transmural inflammation have limited the standardized histological assessment. The current evidence from research proposes that besides clinical and endoscopic healing, the achievement of histological healing constitutes an endpoint to assess disease activity and remission in IBD patients concerning better long-term disease outcomes. Histological alterations may persist even in the absence of endoscopic lesions. For these reasons, new advanced techniques promise to revolutionize the field of IBD by improving the endoscopic and histologic assessment, disease characterization, and ultimately patient care, with an established role in daily practice for objective assessment of lesions. This review outlines the importance of including microscopic evaluation in IBD, highlighting the clinical benefits of a deep state of disease remission using validated diagnostic methods and scoring systems for daily clinical practice.

Treatment of Patients with Mild to Moderate Ulcerative Colitis: A Middle East Expert Consensus

The prevalence of ulcerative colitis (UC) in the Middle East is increasing, impacting the economic and healthcare burden. The management of patients with mild to moderate UC is still a challenge as several factors can affect optimal care, including drug choice, induction and maintenance dose, treatment optimization and de-escalation, therapy duration, monitoring, and safety profile. We conducted an expert consensus to standardize the management of patients with mild to moderate UC. Sixteen experts in inflammatory bowel diseases, through a well-established and accepted Delphi methodology, voted and approved eight statements in order to provide practical guidance to clinicians in the Middle East.

Mesalazine granules promote disease clearance in patients with mild-to-moderate ulcerative colitis

BACKGROUND

Over the past decade, treatment targets for ulcerative colitis (UC) have become more stringent, incorporating multiple parameters. Recently, the concept of 'disease clearance'-defined as combined clinical, endoscopic, and histological remission-has been proposed as an ultimate endpoint in treating UC.

OBJECTIVE

To determine the rates of disease clearance in patients with mild-to-moderate UC treated with different doses of mesalazine granules as induction therapy.

METHODS

In a post hoc analysis, data were pooled from four randomised, active-controlled, phase 3 clinical trials in patients with mild-to-moderate UC receiving 8-week induction therapy with mesalazine granules at daily doses of 1.5, 3.0 or 4.5 g. Rates of clinical, endoscopic, and histological remission were determined using stringent criteria and used to calculate rates of the composite endpoints of clinical plus endoscopic remission, endoscopic plus histological remission, and disease clearance (clinical plus endoscopic plus histological remission).

RESULTS

A total of 860 patients were included in the analysis. Among the total population, 20.0% achieved disease clearance with mesalazine granules: 13.1% in patients receiving 1.5 g mesalazine granules/day, 21.8% in those receiving 3.0 g/day and 18.9% in those receiving 4.5 g/day. Among patients with moderate UC, 16.8% achieved disease clearance: 7.1% with 1.5 g/day, 18.8% with 3.0 g/day and 16.2% with 4.5 g/day.

CONCLUSION

Disease clearance, proposed to be predictive of improved long-term outcomes, can be achieved in a clinically meaningful proportion of mild-to-moderate UC patients treated with mesalazine granules. A daily dose of 3.0 g appears optimal to reach this target.

Disease clearance in ulcerative colitis: Setting the therapeutic goals for future in the treatment of ulcerative colitis

Ulcerative colitis, one of the phenotypic patterns of inflammatory bowel disease, should be considered a progressive disease with an increased risk of complications if intestinal inflammation is not adequately controlled. The advent of new lines of treatment for this condition has changed and expanded the therapeutic goals to modify its natural history and evolution. The concept of "disease clearance" in ulcerative colitis aims to achieve clinical and biological remission as well as mucosal healing (endoscopic, histological, and in future molecular) in these patients. This review provides the available data on each of the goals of disease clearance in ulcerative colitis to be considered for application in clinical practice in the coming years.

A scoping review on early inflammatory bowel disease: definitions, pathogenesis, and impact on clinical outcomes

Background

Crohn's disease (CD) and ulcerative colitis (UC) arise from a dysregulation of the balance between commensal microbiota and mucosal-associated immune system, in patients with genetic and environmental predisposition. Different pathophysiological mechanisms have been reported to influence disease history, with impact on disease phenotype and risk of complications.

Objectives

This review aims to summarize the definitions of early CD and UC, analyze the underlying immunological mechanisms, and evaluate the impact of recognizing and treating early inflammatory bowel disease (IBD) on patients' prognosis (short- and long-term outcomes).

Design

To address this issue, we have performed a scoping review.

Data sources and methods

Three online databases (MEDLINE, Web of Science, and ScienceDirect) were searched and the results were independently screened by two reviewers.

Results

From 683 records identified, 42 manuscripts evaluating early IBD in adult patients were included. The 'early CD' concept was first described in 2008. Four years later, an international consensus proposed the definition of diagnosis up to 18 months, in patients without previous or current need for disease-modifying therapies. Several other definitions have been proposed; the '2 years since diagnosis' is the most used, regardless of disease characteristics or medication. The amount of evidence on early UC is lower and more recent. Regarding early disease pathogenesis, most theories emphasize the prominent role of innate immunity, followed by early-Th1 adaptive response.

Conclusion

The treatment of early CD seems to be crucial for the management of CD patients, impacting short-, medium-, and long-term outcomes. On the other hand, the early treatment of UC appears to be less advantageous, yet evidence comes from only a few retrospective studies.