Normalization of Fecal Calprotectin Within 12 Months of Diagnosis Is Associated With Reduced Risk of Disease Progression in Patients With Crohn's Disease

Comparison of Fecal Calprotectin and Myeloperoxidase in Predicting Outcomes in Inflammatory Bowel Disease

BACKGROUND

Biomarkers have been proposed as surrogate treatment targets for the management of inflammatory bowel disease (IBD); however, their relationship with IBD-related complications remains unclear. This study investigated the utility of neutrophil biomarkers fecal calprotectin (fCal) and fecal myeloperoxidase (fMPO) in predicting a complicated IBD course.

METHODS

Participants with IBD were followed for 24 months to assess for a complicated IBD course (incident corticosteroid use, medication escalation for clinical disease relapse, IBD-related hospitalizations/surgeries). Clinically active IBD was defined as Harvey-Bradshaw index >4 for Crohn's disease (CD) and simple clinical colitis activity index >5 for ulcerative colitis (UC). Area under the receiver-operating-characteristics curves (AUROC) and multivariable logistic regression assessed the performance of baseline symptom indices, fCal, and fMPO in predicting a complicated disease IBD course at 24 months.

RESULTS

One hundred and seventy-one participants were included (CD, n = 99; female, n = 90; median disease duration 13 years [interquartile range, 5-22]). Baseline fCal (250 μg/g; AUROC = 0.77; 95% confidence interval [CI], 0.69-0.84) and fMPO (12 μg/g; AUROC = 0.77; 95% CI, 0.70-0.84) predicted a complicated IBD course. Fecal calprotectin (adjusted OR = 7.85; 95% CI, 3.38-18.26) and fMPO (adjusted OR = 4.43; 95% CI, 2.03-9.64) were associated with this end point after adjustment for other baseline variables including clinical disease activity. C-reactive protein (CRP) was inferior to fecal biomarkers and clinical symptoms (pdifference < .05) at predicting a complicated IBD course. A combination of baseline CRP, fCal/fMPO, and clinical symptoms provided the greatest precision at identifying a complicated IBD course.

CONCLUSIONS

Fecal biomarkers are independent predictors of IBD-related outcomes and are useful adjuncts to routine clinical care.

Comparative Effectiveness of Biologic Therapies in Preventing Penetrating Complications in Patients With Crohn's Disease

BACKGROUND & AIMS

Comparative effectiveness of biologics in preventing penetrating disease (PD) in Crohn's disease (CD) is not well established. We compared the risk of developing luminal and perianal PD (LPD and PPD) between biologics used as first-line therapies.

METHODS

Adults (>17 years) with CD who initiated their first biologic (anti-tumor necrosis factor [anti-TNF], ustekinumab [UST], or vedolizumab [VDZ]) were identified from Merative Commercial Database (2006 and 2020). We excluded preexisting PD using a minimum look-back period of 1 year. Cohorts were balanced by inverse probability of treatment weighting based on age, sex, comorbidities, prior CD surgery, and CD severity. Pairwise comparisons were performed by Cox proportional hazards models, adjusted for immunomodulator exposure, and with biologic exposure treated as a time-dependent variable based on a medication possession ratio of 0.8.

RESULTS

Our analysis included 40,693 patients: 93% anti-TNF, 3% UST, and 4% VDZ. After inverse probability of treatment weighting all comparisons were well balanced. Anti-TNF was protective against LPD (hazard ratio, 0.66; 95% confidence interval, 0.55-0.78; P < .0001) and PPD (hazard ratio, 0.88; 95% confidence interval, 0.80-0.96; P = .0045) compared with VDZ and LPD (hazard ratio, 0.37; 95% confidence interval, 0.30-0.46; P < .0001) compared with UST. There were no significant differences in the risk of LPD and PPD between VDZ and UST. These results were similar after limiting the study period to after 2016.

CONCLUSIONS

Anti-TNF therapy was associated with a lower risk of LPD and PPD compared with VDZ, and lower risk of LPD compared with UST. Further studies are needed to validate these findings and to determine potential reasons for these differences.

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

A treat-to-target (T2T) approach applies the principles of early intervention and tight disease control to optimise long-term outcomes in Crohn's disease. The Selecting Therapeutic Targets in Inflammatory Bowel Disease (STRIDE)-II guidelines specify short, intermediate, and long-term treatment goals, documenting specific treatment targets to be achieved at each of these timepoints. Scheduled appraisal of Crohn's disease activity against pre-defined treatment targets at these timepoints remains central to determining whether current therapy should be continued or modified. Consensus treatment targets in Crohn's disease comprise combination clinical and patient-reported outcome remission, in conjunction with biomarker normalisation and endoscopic healing. Although the STRIDE-II guidelines endorse the pursuit of endoscopic healing, clinicians must consider that this may not always be appropriate, acceptable, or achievable in all patients. This underscores the need to engage patients at the outset in an effort to personalise care and individualise treatment targets. The use of non-invasive biomarkers such as faecal calprotectin in conjunction with cross-sectional imaging techniques, particularly intestinal ultrasound, holds great promise; as do emerging treatment targets such as transmural healing. Two randomised clinical trials, namely, CALM and STARDUST, have evaluated the efficacy of a T2T approach in achieving endoscopic endpoints in patients with Crohn's disease. Findings from these studies reflect that patient subgroups and Crohn's disease characteristics likely to benefit most from a T2T approach, remain to be clarified. Moreover, outside of clinical trials, data pertaining to the real-world effectiveness of a T2T approach remains scare, highlighting the need for pragmatic real-world studies. Despite the obvious promise of a T2T approach, a lack of guidance to support its integration into real-world clinical practice has the potential to limit its uptake. This highlights the need to describe strategies, processes, and models of care capable of supporting the integration and execution of a T2T approach in real-world clinical practice. Hence, this review seeks to examine the current and emerging literature to provide clinicians with practical guidance on how to incorporate the principles of T2T into routine clinical practice for the management of Crohn's disease.

To STRIDE or not to STRIDE: a critique of "treat to target" in Crohn´s disease

INTRODUCTION

The STRIDE consensus suggested to focus on mucosal healing, based on biomarkers and endoscopy, in addition to clinical endpoints as treatment target. This narrative review provides a critique of this concept in Crohn´s disease.

AREAS COVERED

We analyze and discuss the limitations of endpoints as targets, their currently limited achievability, and the controversial evidence relating to 'treat to target.' The relevant publications in Pubmed were identified in a literature review with the key word 'Crohn´s disease.'

EXPERT OPINION

All targets and endpoints have their limitations, and, even if reached, not all have unequivocally been shown to improve prognosis. The major deficiency of STRIDE is not only the lack of validation and agreement upon endpoints but little evidence of their achievability in a sizable proportion of patients by dose or timing adjustments or switching the medication. Above all, the concept should be based on clear evidence that patients indeed benefit from appropriate escalation of treatment and relevant controlled studies in this regard have been controversial. Until the STRIDE approach is proven to be superior to standard treatment focusing on clinical well-being, the field should remain reluctant and expect more convincing evidence before new targets are approved.

Early intervention with biologic therapy in Crohn´s disease: how early is early?

BACKGROUND

Early biologic therapy within the first 18-24 months after diagnosis is associated with improved clinical outcomes in Crohn's disease [CD]. However, the definition of the best time to initiate biologic therapy remains unclear. We aimed to assess if there is an optimal timing for early biologic therapy initiation.

METHODS

This was a multicentre retrospective cohort study including newly diagnosed CD patients who started anti-tumour necrosis factor [TNF] therapy within 24 months from diagnosis. The timing of initiation of biologic therapy was categorised as ≤6, 7-12, 13-18, and 19-24 months. The primary outcome was CD-related complications defined as a composite of progression of Montreal disease behaviour, CD-related hospitalisations, or CD-related intestinal surgeries. Secondary outcomes included clinical, laboratory, endoscopic, and transmural remission.

RESULTS

We included 141 patients where 54%, 26%, 11%, and 9% started biologic therapy at ≤6, 7-12, 13-18, and 19-24 months after diagnosis, respectively. A total of 34 patients [24%] reached the primary outcome: 8% had progression of disease behaviour, 15% were hospitalised, and 9% required surgery. There was no difference in the time to a CD-related complication according to the time of initiation of biologic therapy within the first 24 months. Clinical, endoscopic, and transmural remission was achieved in 85%, 50%, and 29%, respectively, but no differences were found according to the time of initiation of biologic therapy.

CONCLUSION

Starting anti-TNF therapy within the first 24 months after diagnosis was associated with a low rate of CD-related complications and high rates of clinical and endoscopic remission, although we found no differences with earlier initiation within this window of opportunity.

Longitudinal Fecal Calprotectin Profiles Characterize Disease Course Heterogeneity in Crohn's Disease

BACKGROUND AND AIMS

The progressive nature of Crohn's disease is highly variable and hard to predict. In addition, symptoms correlate poorly with mucosal inflammation. There is therefore an urgent need to better characterize the heterogeneity of disease trajectories in Crohn's disease by utilizing objective markers of inflammation. We aimed to better understand this heterogeneity by clustering Crohn's disease patients with similar longitudinal fecal calprotectin profiles.

METHODS

We performed a retrospective cohort study at the Edinburgh IBD Unit, a tertiary referral center, and used latent class mixed models to cluster Crohn's disease subjects using fecal calprotectin observed within 5 years of diagnosis. Information criteria, alluvial plots, and cluster trajectories were used to decide the optimal number of clusters. Chi-square test, Fisher's exact test, and analysis of variance were used to test for associations with variables commonly assessed at diagnosis.

RESULTS

Our study cohort comprised 356 patients with newly diagnosed Crohn's disease and 2856 fecal calprotectin measurements taken within 5 years of diagnosis (median 7 per subject). Four distinct clusters were identified by characteristic calprotectin profiles: a cluster with consistently high fecal calprotectin and 3 clusters characterized by different downward longitudinal trends. Cluster membership was significantly associated with smoking (P = .015), upper gastrointestinal involvement (P < .001), and early biologic therapy (P < .001).

CONCLUSIONS

Our analysis demonstrates a novel approach to characterizing the heterogeneity of Crohn's disease by using fecal calprotectin. The group profiles do not simply reflect different treatment regimens and do not mirror classical disease progression endpoints.

Safety, Effectiveness, and Treatment Persistence of Subcutaneous Vedolizumab in IBD: A Multicenter Study From the United Kingdom

BACKGROUND AND AIMS

Despite intravenous (IV) vedolizumab being established for treatment of inflammatory bowel disease (IBD), the novel subcutaneous (SC) route of administration may provide numerous incentives to switch. However, large-scale real-world data regarding the long-term safety and effectiveness of this strategy are lacking.

METHODS

IBD patients on IV vedolizumab across 11 UK sites agreed to transition to SC injections or otherwise continued IV treatment. Data regarding clinical disease activity (Simple Clinical Colitis Activity Index, partial Mayo score, and modified Harvey-Bradshaw Index), biochemical markers (C-reactive protein and calprotectin), quality of life (IBD control), adverse events, treatment persistence, and disease-related outcomes (namely corticosteroid use, IBD-related hospitalization, and IBD-related surgery) were retrospectively collected from prospectively maintained clinical records at baseline and weeks 8, 24, and 52.

RESULTS

Data from 563 patients (187 [33.2%] Crohn's disease, 376 [66.8%] ulcerative colitis; 410 [72.8%] SC, 153 [27.2%] IV) demonstrated no differences in disease activity, remission rates, and quality of life between the SC and IV groups at all time points. Drug persistence at week 52 was similar (81.1% vs 81.2%; P = .98), as were rates of treatment alteration due to either active disease (12.2% vs 8.9%; P = .38) or adverse events (3.3% vs 6.3%; P = .41). At week 52, there were equivalent rates of adverse events (9.8% vs 7.8%; P = .572) and disease-related outcomes. IBD control scores were equivalent in both IV-IV and IV-SC groups.

CONCLUSIONS

Switching to SC vedolizumab appears as effective, safe, and well tolerated as continued IV treatment and maintains comparable disease control and quality of life as IV treatment at 52 weeks.

Establishing key performance indicators for inflammatory bowel disease in the UK

Background and aims

Healthcare quality improvement (QI) is the systematic process to continuously improve the quality of care and outcomes for patients. The landmark Inflammatory Bowel Disease (IBD) UK National Audits provided a means to measure the variation in care, highlighting the need to define the standards of excellence in IBD care. Through a consensus approach, we aimed to establish key performance indicators (KPIs), providing reliable benchmarks for IBD care delivery in UK.

Methods

KPIs that measure critical aspects of a patient journey within an IBD service were identified though stakeholder meetings. A two-stage Delphi consensus was then conducted. The first involved a multidisciplinary team of IBD clinicians and patients to refine definitions and methodology. The second stage assessed feasibility and utility of the proposed QI process by surveying gastroenterology services across UK.

Results

First, the four proposed KPIs were refined and included time from primary care referral to diagnosis in secondary care, time to treatment recommendation following a diagnosis, appropriate use of steroids and advanced therapies prescreening and assessment. Second, the Delphi consensus reported >85% agreement on the feasibility of local adoption of the QI process and >75% agreement on the utility of benchmarking of the KPIs.

Conclusions

Through a structured approach, we propose quantifiable KPIs for benchmarking to improve and reduce the individual variation in IBD care across the UK.

Macrophages in intestinal homeostasis and inflammatory bowel disease

Macrophages are essential for the maintenance of intestinal homeostasis, yet appear to be drivers of inflammation in the context of inflammatory bowel disease (IBD). How these peacekeepers become powerful aggressors in IBD is still unclear, but technological advances have revolutionized our understanding of many facets of their biology. In this Review, we discuss the progress made in understanding the heterogeneity of intestinal macrophages, the functions they perform in gut health and how the environment and origin can control the differentiation and longevity of these cells. We describe how these processes might change in the context of chronic inflammation and how aberrant macrophage behaviour contributes to IBD pathology, and discuss how therapeutic approaches might target dysregulated macrophages to dampen inflammation and promote mucosal healing. Finally, we set out key areas in the field of intestinal macrophage biology for which further investigation is warranted.

Multiple infliximab biosimilar switches appear to be safe and effective in a real-world inflammatory bowel disease cohort

BACKGROUND

Switching from originator infliximab (IFX) to biosimilar IFX is effective and safe. However, data on multiple switching are scarce. The Edinburgh inflammatory bowel disease (IBD) unit has undertaken three switch programmes: (1) Remicade to CT-P13 (2016), (2) CT-P13 to SB2 (2020), and (3) SB2 to CT-P13 (2021).

OBJECTIVE

The primary endpoint of this study was to assess CT-P13 persistence following switch from SB2. Secondary endpoints included persistence stratified by the number of biosimilar switches (single, double and triple), effectiveness and safety.

METHODS

We performed a prospective, observational, cohort study. All adult IBD patients on IFX biosimilar SB2 underwent an elective switch to CT-P13. Patients were reviewed in a virtual biologic clinic with protocol driven collection of clinical disease activity, C-reactive protein (CRP), faecal calprotectin (FC), IFX trough/antibody levels, and drug survival.

RESULTS

297 patients (CD n = 196 [66%], ulcerative colitis/inflammatory bowel disease unclassified n = 101, [34%]) were switched (followed-up: 7.5 months [6.8-8.1]). This was the third, second and first IFX switch for 67/297 (22.5%), 138/297 (46.5%) and 92/297 (31%) of the cohort respectively. 90.6% of patients remained on IFX during follow-up. The number of switches was not independently associated with IFX persistence after adjusting for confounders. Clinical (p = 0.77), biochemical (CRP ≤5 mg/ml; p = 0.75) and faecal biomarker (FC<250 µg/g; p = 0.63) remission were comparable at baseline, week 12 and week 24.

CONCLUSION

Multiple successive switches from IFX originator to biosimilars are effective and safe in patients with IBD, irrespective of the number of IFX switches.

CT-based radiomics signature of visceral adipose tissue for prediction of disease progression in patients with Crohn's disease: A multicentre cohort study

BACKGROUND

Visceral adipose tissue (VAT) is involved in the pathogenesis of Crohn's disease (CD). However, data describing its effects on CD progression remain scarce. We developed and validated a VAT-radiomics model (RM) using computed tomography (CT) images to predict disease progression in patients with CD and compared it with a subcutaneous adipose tissue (SAT)-RM.

METHODS

This retrospective study included 256 patients with CD (training, n = 156; test, n = 100) who underwent baseline CT examinations from June 19, 2015 to June 14, 2020 at three tertiary referral centres (The First Affiliated Hospital of Sun Yat-Sen University, The First Affiliated Hospital of Shantou University Medical College, and The First People's Hospital of Foshan City) in China. Disease progression referred to the development of penetrating or stricturing diseases or the requirement for CD-related surgeries during follow-up. A total of 1130 radiomics features were extracted from VAT on CT in the training cohort, and a machine-learning-based VAT-RM was developed to predict disease progression using selected reproducible features and validated in an external test cohort. Using the same modeling methodology, a SAT-RM was developed and compared with the VAT-RM.

FINDINGS

The VAT-RM exhibited satisfactory performance for predicting disease progression in total test cohort (the area under the ROC curve [AUC] = 0.850, 95% confidence Interval [CI] 0.764-0.913, P < 0.001) and in test cohorts 1 (AUC = 0.820, 95% CI 0.687-0.914, P < 0.001) and 2 (AUC = 0.871, 95% CI 0.744-0.949, P < 0.001). No significant differences in AUC were observed between test cohorts 1 and 2 (P = 0.673), suggesting considerable efficacy and robustness of the VAT-RM. In the total test cohort, the AUC of the VAT-RM for predicting disease progression was higher than that of SAT-RM (AUC = 0.786, 95% CI 0.692-0.861, P < 0.001). On multivariate Cox regression analysis, the VAT-RM (hazard ratio [HR] = 9.285, P = 0.005) was the most important independent predictor, followed by the SAT-RM (HR = 3.280, P = 0.060). Decision curve analysis further confirmed the better net benefit of the VAT-RM than the SAT-RM. Moreover, the SAT-RM failed to significantly improve predictive efficacy after it was added to the VAT-RM (integrated discrimination improvement = 0.031, P = 0.102).

INTERPRETATION

Our results suggest that VAT is an important determinant of disease progression in patients with CD. Our VAT-RM allows the accurate identification of high-risk patients prone to disease progression and offers notable advantages over SAT-RM.

FUNDING

This study was supported by the National Natural Science Foundation of China, Guangdong Basic and Applied Basic Research Foundation, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Nature Science Foundation of Shenzhen, and Young S&T Talent Training Program of Guangdong Provincial Association for S&T.

TRANSLATION

For the Chinese translation of the abstract see Supplementary Materials section.

Relative Contribution of Disease Activity and Psychological Health to Prognosis of Inflammatory Bowel Disease During 6.5 Years of Longitudinal Follow-Up

BACKGROUND & AIMS

Symptoms of common mental disorders, such as anxiety or depression, are common in inflammatory bowel disease (IBD) and may affect prognosis. However, unlike clinical or biochemical markers of disease activity, psychological health is not a recommended therapeutic target. We assessed relative contribution of poor psychological health and clinical or biochemical activity to prognosis.

METHODS

Demographic features, IBD subtype, treatments, and anxiety and depression scores were recorded at baseline for 760 adults, with clinical activity determined using validated scoring systems. Fecal calprotectin was analyzed in 379 (49.9%) patients (≥250 μg/g used to define biochemical activity). Glucocorticosteroid prescription or flare, escalation, hospitalization, intestinal resection, or death were assessed during 6.5 years of follow-up. Occurrence was compared using multivariate Cox regression across 4 patient groups according to presence of disease remission or activity, with or without symptoms of a common mental disorder, at baseline.

RESULTS

In total, 718 (94.5%) participants provided data. Compared with clinical remission without symptoms of a common mental disorder at baseline, need for glucocorticosteroid prescription or flare (hazard ratio [HR], 2.36; 95% confidence interval [CI], 1.58-3.54), escalation (HR, 1.65; 95% CI, 1.14--2.40), and death (HR, 4.99; 95% CI, 1.80-13.88) were significantly higher in those with clinical activity and symptoms of a common mental disorder. Rates in those with clinical remission and symptoms of a common mental disorder at baseline or those with clinical activity without symptoms of a common mental disorder were not significantly higher. Similarly, with biochemical activity and symptoms of a common mental disorder, rates of glucocorticosteroid prescription or flare (HR, 2.48; 95% CI, 1.38-4.46), escalation (HR, 2.97; 95% CI, 1.74-5.06), hospitalization (HR, 3.10; 95% CI, 1.43-6.68), and death (HR, 6.26; 95% CI, 2.23-17.56) were significantly higher.

CONCLUSIONS

Psychological factors are important determinants of poor prognostic outcomes in IBD and should be considered as a therapeutic target.

Tools for the Diagnosis and Management of Crohn's Disease

Numerous tools have emerged over recent decades to aid in the increasingly complex management of patients with Crohn's disease (CD) beyond endoscopy, including video capsule endoscopy, magnetic resonance enterography, computed tomography enterography, a variety of biomarkers, and even wearable biosensors and smartphone applications. These tools have allowed for a more sophisticated and less invasive complementary approach to the evaluation of disease activity and treatment response in patients with CD. This article details the characteristics, practical application, and limitations of these various modalities and discusses how updated guidelines are now incorporating many of them into a treat-to-target strategy.

Disease Monitoring in Inflammatory Bowel Disease: Evolving Principles and Possibilities

Inflammatory bowel disease is a progressive and debilitating condition. Early and effective treatment using a treat-to-target approach is key to improving patient outcomes. Therefore, proactive monitoring is essential to ensure that treatment strategies are working and targets are being met. In this review we discuss the current monitoring tools available to us and how they can be used. We also discuss the importance of monitoring during key phases of the disease and propose an optimum treat-to-target monitoring strategy for Crohn's disease and ulcerative colitis. Regarding the advent of new technology, we discuss how this may improve our monitoring capabilities and how we envisage future monitoring strategies of inflammatory bowel diseases.

A Clinical Prediction Model to Determine Probability of Response to Certolizumab Pegol for Crohn's Disease

BACKGROUND

Certolizumab pegol (CZP) is effective for moderately to severely active Crohn's disease (CD). Higher plasma concentrations are associated with better outcomes and increased drug clearance is the driver of subtherapeutic CZP concentrations.

OBJECTIVE

We aimed to develop a prediction model incorporating predicted CZP clearance and patient variables to allow estimation of the probability for remission prior to initiating therapy.

METHODS

A population pharmacokinetic model estimated baseline CZP clearance in patients with CD from nine phase II and III trials. Multivariable prediction models were developed and validated using the PRECiSE 1 and PRECiSE 2 datasets to identify candidate predictors for a composite remission outcome (Crohn's Disease Activity Index ≤ 150 and fecal calprotectin concentration ≤ 250 μg/g) at Weeks 6 or 26. An online clinical decision support tool (CDST) was developed.

RESULTS

Baseline predicted CZP clearance ≥ 0.5 L/day was associated with subtherapeutic Week 6 CZP plasma concentrations. Baseline weight (odds ratio [OR] 1.04; 95% confidence interval [CI] 1.02-1.07), calculated CZP clearance (OR 0.92; 95% CI 0.87-0.96), hematocrit (OR 2.55; 95% CI 1.43-4.54), and fecal calprotectin (OR 0.66; 95% CI 0.54-0.80) were associated with Week 6 remission (p ≤ 0.0015 for all predictors). Baseline weight (OR 1.04; 95% CI 1.02-1.07), calculated CZP clearance (OR 0.93; 95% CI 0.88-0.97), and Patient-Reported Outcome-2 (PRO2) (OR 0.93; 95% CI 0.87-0.99) were associated with Week 26 remission (p ≤ 0.033 for all predictors).

CONCLUSIONS

Patients who are predicted to have accelerated baseline CZP clearance are at risk of subtherapeutic CZP concentrations. Patient-level probabilities for a composite remission outcome can be predicted for patients with CD by entering commonly available patient- and disease-related factors into an online CDST ( https://premedibd.com ) incorporating predicted CZP clearance.

Role of Biomarkers in the Diagnosis and Treatment of Inflammatory Bowel Disease

The number of patients with inflammatory bowel disease (IBD) is increasing worldwide. Endoscopy is the gold standard to assess the condition of IBD. The problem with this procedure is that the burden and cost on the patient are high. Therefore, the identification of a reliable biomarker to replace endoscopy is desired. Biomarkers are used in various situations such as diagnosis of IBD, evaluation of disease activity, prediction of therapeutic effect, and prediction of relapse. C-reactive protein and fecal calprotectin have a lot of evidence as objective biomarkers of disease activity in IBD. The usefulness of the fecal immunochemical test, serum leucine-rich glycoprotein, and urinary prostaglandin E major metabolite have also been reported. Herein, we comprehensively review the usefulness and limitations of biomarkers that can be used in daily clinical practice regarding IBD. To date, no biomarker is sufficiently accurate to replace endoscopy; however, it is important to understand the characteristics of each biomarker and use the appropriate biomarker at the right time in daily clinical practice.

Efficacy of anti-TNF dosing interval lengthening in adolescents and young adults with inflammatory bowel disease in sustained remission (FREE-study): protocol for a partially randomised patient preference trial

INTRODUCTION

Anti-tumour necrosis factor (TNF) therapy has greatly improved treatment outcomes in patients with inflammatory bowel disease (IBD), but long-term use is associated with cutaneous reactions, susceptibility to infections and frequent injections or hospital visits. Several non-controlled studies have demonstrated that dose reduction is feasible for a subset of patients, provided that early detection of a disease flare is possible. Here, we aim to compare the effectiveness of interval lengthening with standard dosing in maintaining remission in young patients with IBD.

METHODS AND ANALYSIS

In this international, prospective, non-inferiority, partially randomised patient preference trial, we aim to recruit 148 patients aged 12-25 years with luminal Crohn's disease or ulcerative colitis in sustained remission (ie, three consecutive in-range faecal calprotectin (FC) results or recently confirmed endoscopic remission). In the interventional arm, the dosing interval will be lengthened from 8 to 12 weeks for infliximab users and from 2 to 3 weeks for adalimumab users. In the control group, standard dosing will be continued. Rapid tests will be performed for FC every 4 weeks and for anti-TNF trough levels every 12 weeks. The primary outcome is the cumulative incidence of out-of-range FC results at 48-week follow-up. Secondary endpoints include time to get out-of-range FC results, cumulative incidence of adverse effects, proportion of patients progressing to loss of response and identification of predictors of successful interval lengthening.

ETHICS AND DISSEMINATION

The protocol has been approved by the Medical Ethics Review Committee of the University Medical Centre Groningen and is pending at the other participating centres. Results will be disseminated in peer-reviewed journals and presented at scientific meetings.

TRIAL REGISTRATION NUMBER

EudraCT number: 2020-001811-26; ClinicalTrials.gov Identifier: NCT04646187. Protocol version 4, date 17 September 2021.

Approach to the Management of Recently Diagnosed Inflammatory Bowel Disease Patients: A User's Guide for Adult and Pediatric Gastroenterologists

Inflammatory bowel diseases (IBDs), including Crohn's disease and ulcerative colitis, are chronic, progressive, immune-mediated diseases of adults and children that have no cure. IBD can cause significant morbidity and lead to complications such as strictures, fistulas, infections, and cancer. In children, IBD can also result in growth impairment and pubertal delays. IBD is highly heterogenous, with severity ranging from mild to severe and symptoms ranging from mild to debilitating. Delay in IBD diagnosis, especially in Crohn's disease, is common and associated with adverse outcomes. Early diagnosis and prompt institution of treatment are the cornerstones for improving outcomes and maximizing health. Early diagnosis requires a low threshold of suspicion and red flags to guide early specialist referral at the primary provider level. Although the armamentarium of IBD medications is growing, many patients will not respond to treatment, and the selection of first-line therapy is critical. Risk stratification of disease severity, based on clinical, demographic, and serologic markers, can help guide selection of first-line therapy. Clinical decision support tools, genomics, and other biomarkers of response to therapy and risk of adverse events are the future of personalized medicine. After starting appropriate therapy, it is important to confirm remission using objective end points (treat to target) with continued control of inflammation with adjustment of therapy using surrogate biomarkers (tight control). Lastly, IBD therapy extends far beyond medications, and other aspects of the overall health and wellbeing of the patient are critical. These include preventive health, nutrition, and psychobehavioral support addressing patients' concerns around complementary therapy and medication adherence, prevention of disability, and ensuring open communication.

Fecal calprotectin concentration to assess endoscopic and histologic remission in patients with cancer with immune-mediated diarrhea and colitis

Background

Immune-mediated diarrhea and colitis (IMDC) is currently diagnosed and monitored by evaluating clinical symptoms. Deep remission is determined by endoscopic and histologic evaluation of the disease process. However, repeating these invasive procedures frequently can become cumbersome. We sought to assess the role of fecal calprotectin (FC) concentration as a non-invasive biomarker of endoscopic or histologic remission.

Methods

We performed a retrospective study of patients with IMDC who were tested for FC at IMDC onset and after IMDC treatment between June 2016 and March 2020. Patient demographics, clinical variables, and FC data were collected and analyzed to determine the optimal cut-off FC concentration to predict endoscopic and histologic remission.

Results

Our sample comprised 77 patients with a median age of 62 years; 66% were male and 94% were Caucasian. Sixty-five patients (84%) achieved clinical remission, 46 (60%) achieved endoscopic remission, and 24 (31%) achieved histologic remission after IMDC treatment. FC concentrations decreased from the time of IMDC onset to the end of treatment (p<0.001). High FC concentrations were associated with evident endoscopic inflammation (p=0.003) and acute/chronic active colitis (p=0.025) which positively correlated with the Mayo Endoscopic Subscore (r=0.615, p=0.001) at the time of IMDC onset. In patients who achieved endoscopic remission after treatment, a significantly lower FC concentration was observed at IMDC onset (p=0.006) and after treatment (p<0.001) compared with those without endoscopic remission. The cut-off FC concentration to predict endoscopic remission was ≤116 μg/g and for histologic remission ≤80 μg/g; these cut-offs had optimal specificity (94% and 85%, respectively) and positive predictive value (0.91 and 0.38, respectively).

Conclusions

FC concentration may serve as a non-invasive biomarker to predict endoscopic and histologic remission in patients receiving treatment for IMDC, minimizing the need for frequent invasive endoscopies. Future prospective studies are needed to provide further insight on the role of this marker in disease surveillance.