Predictors of Crohn's disease

Magnetic resonance enterography to predict subsequent disabling Crohn's disease in newly diagnosed patients (METRIC-EF)-multivariable prediction model, multicentre diagnostic inception cohort

OBJECTIVES

Magnetic resonance enterography (MRE) is a first-line investigation to diagnose Crohn's disease (CD), but its role for prognostication is unknown. Accordingly, we assessed the predictive ability of prognostic models including MRE scores (MRE Global Score (MEGS), simplified MR Index of Activity (sMARIA), and Lémann index (LI)) against models using clinical predictors alone for the development of modified Beaugerie disabling CD (MBDD) within 5 years of diagnosis.

METHODS

This was a multicentre, diagnostic inception cohort of patients with newly diagnosed CD across 9 UK hospitals, followed for 4 years or more. We censored development of MBDD ≤ 90 days from diagnosis, and used time-to-event models using Royston-Parmer flexible parametric models.

RESULTS

We included 194 patients, median age 29, IQR 22-44 years, 52% female. Within 5 years of diagnosis, 42% (81/194) developed MBDD. In univariable analysis, initial steroid requirement was associated with increased risk of developing MBDD (HR 2.11 (95% CI 1.36, 3.26). The baseline clinical model had 49% (39, 60) sensitivity and 66% (57, 74) specificity for predicting the top 40% of patients with the greatest risk of developing MBDD, and 86% (77, 92) sensitivity and 35% (27, 45) specificity for predicting the development of MBDD in patients with an absolute risk of ≥ 10%. There was no significant difference in sensitivity when the MEGS, sMARIA, or LI were added to the baseline clinical model.

CONCLUSIONS

Addition of MRE scores at diagnosis to a multivariable model comprising clinical predictors did not improve prediction of MBDD within 5 years of diagnosis.

KEY POINTS

Question Magnetic resonance enterography (MRE) is important for diagnosing and monitoring Crohn's disease (CD), but primary research evaluating its prognostic role is lacking. Findings Adding MRE findings at diagnosis to a multivariable model comprising clinical predictors did not improve the prediction of disabling CD within 5 years of diagnosis. Clinical relevance When tested in a prospective, multicentre trial, current MRE activity and damage scores at diagnosis did not reliably predict whether patients would subsequently develop disabling CD. Notwithstanding this finding, MRE remains an essential tool for diagnosis and monitoring.

Perianal Fistulizing Crohn's Disease-Associated Anorectal and Fistula Cancers: Systematic Review and Expert Consensus

BACKGROUND & AIMS

Perianal fistulizing Crohn's disease (PFCD)-associated anorectal and fistula cancers are rare but often devastating diagnoses. However, given the low incidence and consequent lack of data and clinical trials in the field, there is little to no guidance on screening and management of these cancers. To inform clinical practice, we developed consensus guidelines on PFCD-associated anorectal and fistula cancers by multidisciplinary experts from the international TOpClass consortium.

METHODS

We conducted a systematic review by standard methodology, using the Newcastle-Ottawa Scale quality assessment tool. We subsequently developed consensus statements using a Delphi consensus approach.

RESULTS

Of 561 articles identified, 110 were eligible, and 76 articles were included. The overall quality of evidence was low. The TOpClass consortium reached consensus on 6 structured statements addressing screening, risk assessment, and management of PFCD-associated anorectal and fistula cancers. Patients with long-standing (>10 years) PFCD should be considered at small but increased risk of developing perianal cancer, including squamous cell carcinoma of the anus and anorectal carcinoma. Risk factors for squamous cell carcinoma of the anus, notably human papilloma virus, should be considered. New, refractory, or progressive perianal symptoms should prompt evaluation for fistula cancer. There was no consensus on timing or frequency of screening in patients with asymptomatic perianal fistula. Multiple modalities may be required for diagnosis, including an examination under anesthesia with biopsy. Multidisciplinary team efforts were deemed central to the management of fistula cancers.

CONCLUSIONS

Inflammatory bowel disease clinicians should be aware of the risk of PFCD-associated anorectal and fistula cancers in all patients with PFCD. The TOpClass consortium consensus statements outlined herein offer guidance in managing this challenging scenario.

Defining Radiological Healing in Perianal Fistulizing Crohn's Disease: a TOpClass Global Expert Delphi Consensus

BACKGROUND & AIMS

Perianal fistulising Crohn's disease (pfCD) affects one-fifth of patients with Crohn's disease (CD), significantly affecting their quality of life. Magnetic resonance imaging is the gold standard for evaluating fistula healing in pfCD, but variability in radiological definitions hampers meaningful clinical interpretation and consistent trial design. This study aimed to establish an international consensus on the definition of radiological healing in pfCD.

METHODS

The study was conducted in 2 phases. Phase 1 involved a systematic review to identify magnetic resonance imaging-based variables and indices used to define healing in pfCD, assessing methodological quality using the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) framework. Phase 2 utilized a 2-round online Delphi consensus process with 84 international experts, followed by a stakeholder meeting to achieve consensus (agreement threshold >80%). Results were reported as per Accurate Consensus Reporting Document (ACCORD) guidelines.

RESULTS

A radiologically healed fistula can be defined by the absence of T2-weighted hyperintensity, a completely fibrotic fistula tract and, when contrast is used, the absence of contrast enhancement on post-contrast T1-weighted images (95% consensus). Radiological improvement of a fistula can be defined (80% consensus) by the presence of a least one essential criterion: an increasingly fibrotic fistula tract, an unequivocal reduction in one or more of the following: T2-weighted hyperintensity, fistula diameter, fistula length, abscess size, or contrast enhancement of the fistula tract.

CONCLUSION

This international Delphi consensus standardizes radiological endpoints in pfCD, improving consistency in clinical and research settings. Future studies will validate this definition and assess how radiological changes predict long-term clinical outcomes and quality of life improvements.

Misinterpretation and misapplication of biomarkers in inflammatory bowel disease: how do we avoid this?

INTRODUCTION

The management of inflammatory bowel disease (IBD) has evolved substantially over the past decade, with the emergence of new advanced therapies presenting unprecedented challenges in clinical decision-making. While these therapies provide patients with more opportunities to get better, biomarkers to guide their use remain elusive.

AREAS COVERED

This article highlights the challenges associated with biomarker discovery, interpretation, and application in IBD - based on literature review, first-hand experience of biomarker discovery, and personal opinion. We highlight problems including the misinterpretation of predictive capabilities, lack of independent validation, and reverse causation in retrospective studies, and explain why associations with clinical parameters or seropositivity to microbial antigens often fail to meet the rigorous performance metrics required for clinical utility. The relative need for different biomarkers is also discussed - particularly in light of recent evidence from the PROFILE trial, which emphasizes the considerably greater risk posed by uncontrolled disease than by the potential side-effects of medications.

EXPERT OPINION

Despite multiple challenges, the potential of biomarkers for precision medicine in IBD remains promising, particularly in combination with other clinical and biochemical parameters. Further research into combinatorial biomarker approaches is needed, but must be combined with learning how to communicate results that are inherently uncertain.

Perianal Fistulizing Crohn's Disease: Outcomes of Surgical Repairs and Current State of Stem Cell-Based Therapies

Perianal fistulizing Crohn's disease is one of the most disabling phenotypes of Crohn's disease, due to the severe impairment in quality of life including social and personal wellbeing. A multimodal approach with patient-tailored care is the key to optimal management of this condition. Medical therapy is needed to optimize the luminal disease, and surgical intervention is required to control any associated perianal sepsis and attempt palliative or definitive fistula repair. While several medical and surgical options are available, the majority of patients continue to have symptomatic disease. Fortunately, this continues to drive novel innovations which are revolutionizing the treatment and outcomes of perianal fistulizing Crohn's disease. However, there continues to be a need for randomized trials and consistent metrics utilized for classification and treatment outcomes in order to accurately describe optimal treatment outcomes.

Tryptophan metabolites profile predict remission with dietary therapy in pediatric Crohn's disease

Background

Crohn's disease (CD) exclusion diet combined with partial enteral nutrition (CDED + PEN) or exclusive enteral nutrition (EEN) is effective in inducing remission in mild-to-moderate pediatric CD. Although CDED + PEN is better tolerated and has higher compliance compared to EEN, a subset of patients does not achieve remission. Diet-induced remission is shown to be positively associated with specific changes in tryptophan-metabolites.

Objectives

To investigate whether the abundance of baseline fecal tryptophan-metabolites predicts dietary therapy outcomes in pediatric CD.

Design

Diagnostic accuracy study and secondary analysis of previously conducted Randomized Controlled Trial (RCT).

Methods

Twenty-six patients from previously performed RCT of mild-to-moderate pediatric CD were included. The patients were classified as having clinical remission (R) (n = 19 in total; CDED + PEN = 10 and to EEN = 9) or No-Remission (NR) (n = 7 in total; CDED + PEN = 3 and EEN = 4) following 6 weeks of therapy, based on the Pediatric Crohn's Disease Activity Index score (⩽10 = remission). We performed a targeted quantitative analysis of 21 tryptophan-metabolites in baseline (t = 0) fecal samples from both groups, utilizing liquid chromatography coupled with quadrupole mass spectrometry. Receiver operator characteristic curve (ROC) and random forest analysis (RFA) were used to assess the predictive power of fecal tryptophan-metabolites for dietary outcomes at baseline. Ratios of tryptophan-metabolites were compared to investigate different downstream tryptophan pathways.

Results

Baseline fecal kynurenine level was significantly higher in NR compared to R for CDED + PEN (p = 0.02) and EEN (p = 0.04). ROC analysis highlighted the robust predictive power of kynurenine for CDED + PEN (area under the curve (AUC = 0.97)) and EEN (AUC = 0.88)-induced remission. RFA corroborated these observations. The ratio serotonin/kynurenine was the strongest predictor of CDED + PEN-induced remission (AUC = 1). The ratio 5-hydroxytryptophan/kynurenine (AUC = 0.88) predicted EEN-induced remission. By combining data from CDED + PEN and EEN, kynurenine (AUC = 0.91) and ratios of quinolinic acid/kynurenine (AUC = 0.93) and kynurenine/indole-3-acetic acid (AUC = 0.88) demonstrated strong predictive performance for dietary therapy-induced remission.

Conclusion

Baseline tryptophan metabolites have the potential to serve as a biomarker for dietary remission in pediatric CD. Some tryptophan metabolite ratios showed the most promising predictive capabilities. If confirmed in validation studies, baseline fecal tryptophan markers may be able to provide much-needed guidance to personalize dietary intervention within the management of pediatric CD.

Trial registration

NCT01728870.

Innovative Gastrointestinal Drug Delivery Systems: Nanoparticles, Hydrogels, and Microgrippers

Over the past decade, new technologies have emerged to increase intrinsic potency, enhance bioavailability, and improve targeted delivery of drugs. Most pharmaceutical formulations require multiple dosing due to their fast release and short elimination kinetics, increasing the risk of adverse events and patient non-compliance. Due to these limitations, enormous efforts have focused on developing drug delivery systems (DDSs) for sustained release and targeted delivery. Sustained release strategies began with pioneering research using silicone rubber embedding for small molecules and non-inflammatory polymer encapsulation for proteins or DNA. Subsequently, numerous DDSs have been developed as controlled-release formulations to deliver systemic or local therapeutics, such as small molecules, biologics, or live cells. In this review, we discuss the latest developments of DDSs, specifically nanoparticles, hydrogels, and microgrippers for the delivery of systemic or localized drugs to the gastrointestinal (GI) tract. We examine innovative DDS design and delivery strategies tailored to the GI tract's unique characteristics, such as its extensive length and anatomical complexity, varying pH levels and enzymatic activity across different sections, and intrinsic peristalsis. We particularly emphasize those designed for the treatment of inflammatory bowel disease (IBD) with in vivo preclinical studies.

Development of Time-Aggregated Machine Learning Model for Relapse Prediction in Pediatric Crohn's Disease

INTRODUCTION

Pediatric Crohn's disease (CD) easily progresses to an active disease compared with adult CD, making it important to predict and minimize CD relapses. However, prediction of relapse at various time points (TPs) during pediatric CD remains understudied. We aimed to develop a real-time aggregated model to predict pediatric CD relapse in different TPs and time windows (TWs).

METHODS

This retrospective study was conducted on children diagnosed with CD between 2015 and 2022 at Severance Hospital. Laboratory test results and demographic data were collected starting at 3 months after diagnosis, and cohorts were formed using data from 6 different TPs at 1-month intervals. Relapse-defined as a pediatric CD activity index ≥ 30 points-was predicted, and TWs were 3-7 months with 1-month intervals. The feature importance of the variables in each setting was determined.

RESULTS

Data from 180 patients were used to construct cohorts corresponding to the TPs. We identified the optimal TP and TW to reliably predict pediatric CD relapse with an area under the receiver operating characteristic curve score of 0.89 when predicting with a 3-month TW at a 3-month TP. Variables such as C-reactive protein levels and lymphocyte fraction were found to be important factors.

DISCUSSION

We developed a time-aggregated model to predict pediatric CD relapse in multiple TPs and TWs. This model identified important variables that predicted relapse in pediatric CD to support real-time clinical decision making.

Ileal Predominance in Crohn's Disease Is Associated With Increased Intestinal Surgery and Biological Therapy Use, With Lower Treatment Persistence

INTRODUCTION

Crohn's disease (CD) varies by location, potentially affecting therapy efficacy and surgery risk, although research on this topic is conflicting. This study aims to investigate the independent association between CD location and therapeutic patterns.

METHODS

We analyzed patients with CD diagnosed from January 2005 to May 2023 registered in the nationwide ENEIDA registry. A univariate Cox regression analysis assessed the association of disease location with biologic use and persistence (with treatment discontinuation as a failure event), as well as the use of intestinal resections. A multivariate model was constructed to evaluate the independent association of disease location with therapeutic patterns, controlling for potential confounders such as sex, age at inclusion and diagnosis, disease duration and behavior, previous surgery or biological therapy, extraintestinal manifestations, and perianal disease.

RESULTS

The study included 17,292 patients with a median follow-up period of 6 years (interquartile range 2-10 years). Ileocolonic location was associated with a higher biologic use than colonic location (hazard ratio [HR] 1.30, 95% confidence interval [CI] 1.22-1.38) and ileal disease (HR 1.21, 95% CI 1.16-1.27), independently predicting biologic use (P < 0.001). Ileal location was associated with a lower biologic persistence than ileocolonic location (HR 1.14, 95% CI 1.07-1.21) and colonic disease (HR 1.10, 95% CI 1.01-1.20), independently predicting biologic persistence (P = 0.019). Ileal disease was associated with a higher likelihood of intestinal resections than colonic (HR 2.82, 95% CI 2.45-3.25) and ileocolonic location (HR 1.13, 95% CI 1.05-1.22), independently predicting the use of surgery (P < 0.001).

DISCUSSION

CD location with ileal predominance is associated with a distinct therapeutic pattern, including higher biologic use, lower treatment persistence, and increased rates of intestinal resections.

Consensus definition of a radiologically healed fistula on magnetic resonance imaging in perianal Crohn's disease: an international Delphi study

INTRODUCTION

Perianal fistulising Crohn's disease (pfCD) is a distinct and debilitating phenotype seen in around one-third of patients with CD. Clinical trials in pfCD are increasingly using magnetic resonance imaging (MRI) criteria as a primary endpoint, but there is heterogeneity in the radiological definition of a healed perianal fistula that currently limits our ability to perform meaningful meta-analyses of studies. Our aim is to standardise outcomes through the generation of an international consensus definition of a radiologically healed fistula.

METHODS AND ANALYSIS

This international Delphi consensus study employs a two-part strategy.The first is a systematic review to identify a longlist of variables used to define radiological healing in pfCD. MRI-based indices used to score fistula severity and healing will be assessed for their methodological quality using Consensus-based Standards for the selection of health Measurement Instruments (COSMIN). The systematic review protocol will be conducted using COSMIN methodology and reported using Preferred Reporting Items for Systematic Reviews and Meta-Analyses.The second part will be an online Delphi consensus, guided by the results of the systematic review. Radiologists, gastroenterologists and colorectal surgeons with expertise in the management of pfCD will be invited to take part in two to three rounds of online surveys. Once an a priori threshold of >80% agreement is reached on individual radiological components used to define 'healing' and 'healed', a final meeting of key stakeholders will be organised to generate a consensus definition of a healed fistula.

ETHICS AND DISSEMINATION

The study has been deemed exempt from a formal Research Ethics Committee review as no patients will participate directly in the consensus process, given the technical nature of the research question. The study is registered with the local R&D department (Reference RD24/007). Publication of this study will help standardise radiological endpoint measurement in clinical trials of pfCD and improve the synthesis and meta-analysis of comparative studies.

PROSPERO REGISTRATION NUMBER

CRD42024504334.

Review article: Measuring disease severity in inflammatory bowel disease - Beyond treat to target

BACKGROUND

Inflammatory bowel disease (IBD) follows a heterogenous disease course and predicting a patient's prognosis is challenging. There is a wide burden of illness in IBD and existing tools measure disease activity at a snapshot in time. Comprehensive assessment of IBD severity should incorporate disease activity, prognosis, and the impacts of disease on a patient. This review investigates the concept of disease severity in adults with IBD to highlight key components contributing to this.

METHODS

To perform this narrative review, a Medline search was conducted for full-text articles available at 1st March 2024 using search terms which encompassed disease activity assessment, disease severity, prognosis, natural history of Crohn's disease (CD) and ulcerative colitis (UC), and the burden of IBD.

RESULTS

Current methods of disease assessment in IBD have evolved from a focus on the burden of symptoms to one that includes inflammatory targets, genetic, serological, and proteomic profiles, and assessments of quality-of-life (QoL), disability, and psychosocial health. Longitudinal studies of IBD suggest that the burden of illness is driven by disease phenotype, clinical markers of complicated disease course (previous intestinal resection, corticosteroid use, perianal disease in CD, recent hospitalisations in UC), gut inflammation, and the impact of IBD on the patient.

CONCLUSIONS

Disease severity in IBD can be difficult to conceptualise due to the multitude of factors that contribute to IBD outcomes. Measurement of IBD severity may better encapsulate the full burden of illness rather than gut inflammation alone at a single timepoint and may be associated with longitudinal outcomes.

Ten-year outcomes of a prospective population-based incidence cohort of inflammatory bowel disease patients from Canterbury, New Zealand

BACKGROUND AND AIM

Inflammatory bowel disease (IBD) is a progressive condition where ongoing inflammation in the gastrointestinal tract can lead to complications such as strictures, and fistulae. The long-term outcomes of newly diagnosed patients under current medical therapy can be used to plan health service provision and guide patients.

METHODS

Prospective population-based data on all incident patients diagnosed with IBD in Canterbury was gathered in 2014 (n = 205). The medical records of these patients were followed for medication use, disease progression, hospitalization, surgery and mortality, in the 10 years since their diagnosis. Survival analysis and cox regression determined characteristics associated with earlier time to these outcomes.

RESULTS

Medical records of 184 IBD patients were able to be retrieved. Immunomodulators were used by 62% and biologics by 35%; hospitalization occurred for 42% and surgery for 15%. Montreal phenotype progression occurred for 21 and 7% of the cohort died. Younger age at diagnosis hazard ratio (HR) 2.1 (95% confidence interval [CI] 1.1-4.0) and Crohn's disease HR 1.7 (95% CI 1.1-2.6) was associated with immunomodulator use. Younger age was also associated with biologic use HR 2.9 (95% CI 1.2-6.9). Male gender was associated with surgery HR 2.8 (95% CI 1.2-6.4). Perianal disease at diagnosis (14.7%) was associated with immunomodulator use HR 2.58 (95% CI 1.44-4.59) and Montreal phenotype progression HR 2.93 (95% CI 1.10-7.77).

CONCLUSION

In the 10 years since diagnosis disease progression and treatment escalation occurred for most of this population-based cohort. Earlier intervention for patients with higher-risk characteristics may improve long-term outcomes reducing the burden on health systems.

TOpCLASS Expert Consensus Classification of Perianal Fistulising Crohn's Disease: A Real-world Application in a Serial Fistula MRI Cohort

BACKGROUND AND AIMS

Perianal fistuliing Crohn's disease [PFCD] is an aggressive phenotype of Crohn's disease defined by frequent relapses and disabling symptoms. A novel consensus classification system was recently outlined by the TOpCLASS consortium, which seeks to unify disease severity with patient-centred goals but has not yet been validated. We aimed to apply this to a real-world cohort and to identify factors that predict transition between classes over time.

METHODS

We identified all patients with PFCD and at least one baseline and one follow-up pelvic MRI [pMRI]. TOpCLASS classification, disease characteristics, and imaging indices were collected retrospectively at time periods corresponding with respective MRIs.

RESULTS

We identified 100 patients with PFCD, of whom 96 were assigned TOpCLASS Classes 1-2c at baseline. Most patients [78.1%] started in Class 2b, but changes in classification were observed in 52.1% of all patients. Male sex [72.0%, 46.6%, 40.0%, p = 0.03] and prior perianal surgery [52.0% vs 44.6% vs 40.0%, p = 0.02] were more frequently observed in those with improved class compared to unchanged and worsened class. Baseline pMRI indices were not associated with changes in classification; however, greater improvements in mVAI, MODIFI-CD, and PEMPAC were seen among those who improved. Linear mixed effect modelling identified only male sex [-0.31, 95% CI -0.60 to -0.02] with improvement in class.

CONCLUSION

The TOpCLASS classification highlights the dynamic nature of PFCD over time. However, our ability to predict transitions between classes remains limited and requires prospective assessment. Improvement in MRI index scores over time was associated with a transition to lower TOpCLASS classification.

Fistulizing Perianal Disease as a First Manifestation of Crohn's Disease: A Systematic Review and Meta-Analysis

Background: Incidences of perianal fistulas (PAFs) as a first manifestation of Crohn's disease (CD) vary widely in the literature. Aim: To analyse the percentage of patients with a PAF preceding CD diagnosis and assess the time to diagnosis. Methods: A systematic literature search was conducted. Studies reporting on patients with a PAF preceding CD diagnosis were identified. Primary outcomes were the (weighted) percentage of patients with CD with a PAF preceding CD and their time to CD diagnosis. Secondary outcomes were the (weighted) percentage of patients with CD with a PAF preceding CD diagnosis in predefined patient subgroups, including (1) sex (men vs. women), (2) ethnicity (Asian vs. non-Asian), and (3) age (paediatric (0-18 y) and patients with elderly onset CD (>60 y) vs. adult patients (18-60 y)). Results: Seventeen studies were included (34,030 patients with CD). In the overall CD population, a PAF preceded CD in 8.6% [95%CI; 5.72; 12.71] with a weighted mean time to CD diagnosis of 45.9 (31.3) months. No studies reported details on sex differences in patients with a PAF as a manifesting sign of CD. In Asian populations, a PAF preceded CD in 17.66% [95%CI; 11.45; 26.25], which was significantly higher when compared with non-Asians (4.99% [95%CI; 3.75; 6.60], OR:3.99, p < 0.0001). In adolescents, an incidence of 9.17% [95%CI; 5.92; 13.93] was found with significantly lower incidences in paediatric patients (6.38% [95%CI; 1.84; 19.85], OR:0.53, p < 0.0001), and elderly-onset patients (3.77% [95%CI; 1.68; 8.25], OR:0.44, p = 0.0035). Conclusions: This systematic review shows that in the literature, almost 10% of patients present with a PAF as a first manifestation of CD, with a mean time to diagnosis of almost four years. These results emphasise that increased clinical awareness is needed.

High prevalence of vitamin D deficiency in Taiwanese patients with inflammatory bowel disease

Vitamin D deficiency is common in patients with inflammatory bowel disease (IBD). In this study, we aimed to evaluate the prevalence and risk factors of vitamin D deficiency in a Taiwanese IBD cohort. Vitamin D levels were checked in adult patients with IBD who were treated at Changhua Christian Hospital, a medical center in central Taiwan, from January 2017 to December 2023. The risk factors for vitamin D deficiency were evaluated. 106 adult IBD patients were included, including 20 patients with Crohn's disease and 86 with ulcerative colitis. The median age at diagnosis was 39.2 years. The mean vitamin D level was 22.2 ± 8 ng/mL. Forty-five patients (42.5%) had vitamin D deficiency (vitamin D level < 20 ng/mL). Comparing patients with normal vitamin D levels and those with vitamin D deficiency after multivariate adjustment, female sex and early age at diagnosis were identified as statistically significant risk factors. We found a prevalence of 42.5% of vitamin D deficiency in the Taiwanese IBD population. Understanding this issue is essential for teaching patients and doctors about vitamin D deficiency screening and improving patient outcomes.

Exploring Predictive Biomarkers of Relapse in Ulcerative Colitis: A Proteomics Approach

INTRODUCTION AND AIMS

Risk stratification of subjects with a history of inflammatory bowel disease (IBD) into those likely to relapse and those who will remain quiescent continues to be a significant challenge. The aim of this study was to investigate whether certain proteomic signature profiles or biomarkers during remission are associated with future disease relapse in patients with ulcerative colitis (UC).

METHODS

Endoscopic rectal samples from patients with UC in clinical, endoscopic, and histological remission at index endoscopy were collected, as well as samplers from normal control individuals. The patients were stratified to early relapsers (ERs) if they developed clinical signs of UC flare within 6 months of index endoscopy or nonrelapsers (NRs) if there was no relapse after 36 months of follow-up. The pooled rectal samples from ERs, NRs, and control individuals were subjected to nano-liquid chromatography and tandem mass spectrometry as per standard iTRAQ (isobaric tags for relative and absolute quantitation) workflow methodology. Selected proteomics-yielded candidates were subjected to orthogonal validation via immunoblotting, in a biomarker discovery exercise.

RESULTS

Sixty-one patients were included, of whom 8 had clinical relapse within 6 months from the index endoscopy, and 43 patients had no clinical symptoms of relapse within the 36-month follow-up period. Ten patients who had clinical signs of relapse between 6 and 36 months were excluded. Seventeen control individuals were also included. Soluble proteomics analyses between ERs, NRs, and control individuals revealed a series of upregulated and downregulated proteins. Following orthogonal validation, upregulated TRX (P = .001) and IGHA1 (P = .001) were observed in ERs relative to NRs.

CONCLUSIONS

Several novel candidate tissue biomarkers have been identified in this study, which could discriminate patients with UC at risk of early relapse from those in long-term sustained remission. Our findings may pave the way for pre-emptive UC disease monitoring and therapeutic decision making.

Pharmacological Therapies for the Management of Fistulizing Crohn's Disease: A Systematic Review and Meta-Analysis

BACKGROUND

Fistulas are a debilitating complication of Crohn's disease [CD]. We conducted a systematic review to assess the efficacy of medical therapies for fistulizing CD.

METHODS

MEDLINE, Embase, and CENTRAL were searched on May 26, 2022, for randomized controlled trials [RCTs] of pharmacological therapy in adults with fistulizing CD. The primary outcome was induction and maintenance of fistula response. Pooled risk ratios [RRs] and 95% confidence intervals [CIs] were calculated. GRADE was used to assess the certainty of evidence.

RESULTS

Thirty-eight RCTs were included. Nineteen trials [50%] exclusively involved perianal fistula. The remaining studies included some participants with non-perianal fistula. Pooled RRs for anti-tumour necrosis factor [TNF] agents were not statistically significant for induction [RR 1.36, 95% CI 0.97-1.91] or maintenance of fistula response [RR 1.48, 95% CI 0.97-2.27]. However, in a sensitivity analysis of studies with fistula response as the primary outcome, anti-TNFs were superior to placebo for induction [RR 1.94, 95% CI 1.10-3.41] and maintenance [RR 1.88, 95% CI 1.23-2.88] of fistula response. Oral small molecules [RR 2.56, 95% CI 1.18-5.53] and mesenchymal stem cell [MSC] therapy [RR 1.26, 95% CI 1.01-1.57] were effective for induction of fistula response. Ustekinumab was associated with maintenance of fistula response [RR 1.80, 95% CI 1.04-3.11]. Vedolizumab was not superior to placebo. The certainty of evidence ranged from very low to moderate.

CONCLUSION

Very low- to moderate-certainty evidence suggests that anti-TNF therapy, oral small molecules, ustekinumab, and MSCs are effective for perianal fistulizing CD. Dedicated fistula studies evaluating biologics and small molecules are needed.

Safety and Effectiveness of Ustekinumab for Crohn's Disease With Perianal Manifestations: Ad hoc Analysis Data From 1-Year Post-Marketing Surveillance Study in Japan

Background

Crohn's disease (CD) is an immune-mediated inflammatory disorder of the gastrointestinal tract with perianal disease being one of the challenging possible manifestations. Here, we report, an ad hoc analysis of the safety and effectiveness of 1-year use of ustekinumab (UST) for CD in patients with perianal manifestations using post-marketing surveillance (PMS) data in Japan.

Methods

Among 341 patients enrolled in the PMS, 229 and 224 patients who had baseline Crohn's Disease Activity Index (CDAI) data used for evaluating perianal manifestations were included in the safety and efficacy analysis sets, respectively. Incidence of adverse drug reactions, clinical remission, the mean or its change in CDAI scores, and CDAI items were evaluated through week 52 in the presence or absence of perianal manifestations at baseline. The prevalence of perianal manifestations was also described.

Results

Comparing patients with and without baseline perianal manifestations at week 52, there was no difference in ADR incidence (9.1% [n = 66] vs. 15.3% [n = 163]), no difference in clinical remission (68.3% vs. 59.9%; P = 0.269), and decreased mean change of CDAI score (-82.9 [n = 60] vs. -68.8 [n = 137]). The proportion of patients with perianal manifestations decreased after UST treatment in both biologics-naïve patients (23.5% [n = 4/17]) and patients who had received biologics (35.0% [n = 14/40]) at week 52.

Conclusions

In Japanese clinical practice, UST is safe and effective in CD patients with and without perianal manifestations. The therapy might be also beneficial in those with manifestations regardless of prior use of other biologics.

Burden of perianal disease in Crohn's disease: Accelerating medical therapy and high rates of perianal surgery over the last four decades - Results from a population-based study over four decades

BACKGROUND

Few population-based studies have investigated the prevalence and disease course of perianal manifestation in Crohn's disease.

AIMS

To analyse the prevalence and outcomes of perianal Crohn's disease including medical therapies and need for perianal surgery, over different therapeutic eras based on the time of diagnosis; cohort A (1977-1995), cohort B (1996-2008), and cohort C (2009-2018) METHODS: Patient inclusion lasted between 1977 and 2018. We followed patients prospectively, and regularly reviewed both in-hospital and outpatient records. We defined a perianal surgical procedure as any perianal incision and excision, fistulotomy, or abscess drainage.

RESULTS

We included 946 incident patients. Perianal disease at diagnosis was present in 17.4% (n = 165) of the total cohort, with a declining prevalence in cohorts A/B/C, respectively (24.7%/18.5%/13.2%; p = 0.001). By the end of follow-up, an additional 9.3% (n = 88) of the total cohort developed perianal disease. Cumulative immunosuppressive and biologic exposure increased over time; biologic use was higher in patients with perianal disease [pLog Rank < 0.001]. The overall rate of perianal surgery was 44.7% (113/253), with a probability of 28.3% (95% CI: 25.4-31.2) after 10 years, 41.0% (95% CI: 37.5-44.5) after 20 years, and 64.1% (95% CI: 59-69.2) after 30 years. There was no statistically significant difference in the probability of first perianal surgery among cohorts A/B/C [Log Rank = 0.594].

CONCLUSIONS

The burden of perianal disease and perianal surgery rates were high in this cohort. Therapeutic strategy was accelerated in patients with perianal Crohn's over time with higher exposure to immunosuppressives and biologics. Surgical management of perianal disease remained unchanged amongst the cohorts.

Impact of age at diagnosis on long-term prognosis in patients with intestinal Behçet's disease

BACKGROUND AND AIM

Although age at disease onset is considered to be a significant factor in the prognosis of Crohn's disease, little is known about its influence on the long-term prognosis of those with intestinal Behçet's disease (BD). This study aimed to evaluate the long-term clinical outcomes of patients with intestinal BD according to age of disease onset.

METHODS

Patients diagnosed with intestinal BD at < 18, 18-60, and > 60 years of age were classified into early-onset, adult-onset, and late-onset groups, respectively. The influence of disease onset time on clinical prognosis, including specific medical requirements, BD-related intestinal surgery, hospitalization, and emergency room visits, was compared using the log-rank test in a large cohort of patients with intestinal BD.

RESULTS

Among 780 patients, 21 (2.7%), 672 (86.2%), and 87 (11.1%) comprised the early-onset, adult-onset, and late-onset groups, respectively. Patients in the early-onset group were more likely to require immunosuppressants than those in the adult-onset group (P = 0.048). Nine (42.9%), 158 (23.5%), and 18 (20.7%) patients in the early-onset, adult-onset, and late-onset groups, respectively, underwent intestinal resection. The early-onset group exhibited a higher risk for intestinal resection than the late-onset (P = 0.043) and adult-onset (P = 0.030) groups. The late-onset group exhibited a higher risk for BD-related hospitalization than the adult-onset group (P = 0.023).

CONCLUSIONS

Age at diagnosis affected the clinical course of intestinal BD, including intestinal surgery, hospitalization, and specific medical requirements. Different treatment strategies should be established according to age at diagnosis.

Current Approach to Risk Factors and Biomarkers of Intestinal Fibrosis in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD), especially Crohn's disease (CD), characterized by a chronic inflammatory process and progressive intestinal tissue damage, leads to the unrestrained proliferation of mesenchymal cells and the development of bowel strictures. Complications induced by fibrosis are related to high rates of morbidity and mortality and lead to a substantial number of hospitalizations and surgical procedures, generating high healthcare costs. The development of easily obtained, reliable fibrogenesis biomarkers is essential to provide an important complementary tool to existing diagnostic and prognostic methods in IBD management, guiding decisions on the intensification of pharmacotherapy, proceeding to surgical methods of treatment and monitoring the efficacy of anti-fibrotic therapy in the future. The most promising potential markers of fibrosis include cartilage oligomeric matrix protein (COMP), hepatocyte growth factor activator (HGFA), and fibronectin isoform- extra domain A (ED-A), as well as antibodies against granulocyte macrophage colony-stimulating factor (GM-CSF Ab), cathelicidin (LL-37), or circulatory miRNAs: miR-19a-3p and miR-19b-3p. This review summarizes the role of genetic predisposition, and risk factors and serological markers potentially contributing to the pathophysiology of fibrotic strictures in the course of IBD.

Geldof Expert Consensus Classification of Perianal Fistulizing Crohn's Disease: A Real-World Application in a Serial Fistula MRI Cohort

Background and Aims

Perianal fistulizing Crohn's disease (CD-PAF) is an aggressive phenotype of Crohn's disease (CD) defined by frequent relapses and disabling symptoms. A novel consensus classification system was recently outlined by Geldof et al. that seeks to unify disease severity with patient-centered goals but has not yet been validated. We aimed to apply this to a real-world cohort and identify factors that predict transition between classes over time.

Methods

We identified all patients with CD-PAF and at least one baseline and one follow-up pelvic (pMRI). Geldof Classification, disease characteristics, and imaging indices were collected retrospectively at time periods corresponding with respective MRIs.

Results

We identified 100 patients with CD-PAF of which 96 were assigned Geldof Classes 1 - 2c at baseline. Most patients (78.1%) started in Class 2b, but changes in classification were observed in 52.1% of all patients. Male sex (72.0%, 46.6%, 40.0%, p = 0.03) and prior perianal surgery (52.0% vs 44.6% vs 40.0%, p = 0.02) were more frequently observed in those with improved. Baseline pMRI indices were not associated with changes in classification, however, greater improvements in mVAI, MODIFI-CD, and PEMPAC were seen among those who improved. Linear mixed effect modeling identified only male sex (-0.31, 95% CI -0.60 to -0.02) with improvement in class.

Conclusion

Geldof classification highlights the dynamic nature of CD-PAF over time, however, our ability to predict transitions between classes remains limited and requires prospective assessment. Improvement in MRI index scores over time was associated with a transition to lower Geldof classification.

Clinical Update on the Prevention and Management of Postoperative Crohn's Disease Recurrence

PURPOSE OF REVIEW

Despite advances in therapeutics, a significant portion of patients with Crohn's disease still require surgical management. In this article, we present updates to the natural history, prognostication and postoperative monitoring, and novel therapeutics in the prevention and treatment of postoperative Crohn's disease recurrence.

RECENT FINDINGS

Clinical risk factors have been associated with higher rates of postoperative recurrence (POR), and in recent studies demonstrate an increased cumulative risk with presence of additional risk factors. Additional novel clinical, histologic, and "-omic" risk factors for recurrence have recently been elucidated, including the role of the mesentery on recurrence and perioperative intraabdominal septic complications. High-risk patients benefit most from medical prophylaxis, including anti-TNF with or without immunomodulator therapy to prevent recurrence. New biologics such as vedolizumab and ustekinumab have emerging evidence in the use of prophylaxis, especially with recent REPREVIO trial data. Non-invasive disease monitoring, such as cross-sectional enterography, intestinal ultrasound, and fecal calprotectin, have been validated against ileocolonoscopy. Recent advances in the prediction, prevention, and monitoring algorithms of postoperative Crohn's disease may be leading to a reduction in postoperative recurrence. Ongoing trials will help determine optimal monitoring and management strategies for this at-risk population.

Breath biomarkers in Non-Carcinogenic diseases

The analysis of volatile organic compounds (VOCs) from human matrices like breath, perspiration, and urine has received increasing attention from academic and medical researchers worldwide. These biological-borne VOCs molecules have characteristics that can be directly related to physiologic and pathophysiologic metabolic processes. In this work, gathers a total of 292 analytes that have been identified as potential biomarkers for the diagnosis of various non-carcinogenic diseases. Herein we review the advances in VOCs with a focus on breath biomarkers and their potential role as minimally invasive tools to improve diagnosis prognosis and therapeutic monitoring.

Baseline Clinical Factors Are Associated With Risk of Complications in Crohn's Disease: Appraisal of the American Gastroenterological Association Clinical Care Pathway

INTRODUCTION

The American Gastroenterological Association (AGA) has compiled risk factors that may be predictive of disease complications in Crohn's disease (CD) and ulcerative colitis (UC). The aim of this study was to evaluate the performance of the AGA risk factors for risk stratification in UC and CD.

METHODS

We included participants of 2 cohorts: the Ocean State Crohn's and Colitis Area Registry cohort and the Mayo Clinic cohort. Baseline clinical risk factors were extracted according to the AGA pathway. Our primary end point was defined as follows: (i) any inflammatory bowel disease related-hospitalization, (ii) any inflammatory bowel disease-related bowel surgery, or (iii) any progression of disease. We analyzed the association of the number of AGA risk factors with our end point. Statistical multivariable modeling was performed with Cox proportional hazards model.

RESULTS

A total of 412 patients with CD were included. Comparing ≥3 risk factors with 0-1 risk factor, we found a significantly increased risk of complications in both the Ocean State Crohn's and Colitis Area Registry cohort (hazard ratio [HR] 2.75, 95% confidence interval 1.71-4.41) and Mayo Clinic cohort (HR 2.07, 95% confidence interval 1.11-3.84). Diagnosis at younger age (HR 2.07), perianal disease (HR 1.99), and B2/B3 behavior (HR 1.92) were significantly associated with disease complications. We did not observe a consistent association between number of risk factors nor any specific individual risk factors and risk of disease complications in the 265 patients with UC included.

DISCUSSION

We found a significant association between the number of AGA risk factors and the risk of disease complication in CD; this association was not significant in UC. The presence of ≥ 3 risk factors in CD leads to the highest risk of complications. The AGA care pathway is a useful tool to stratify patients who are at higher risk of disease complications in patients with CD.

Estimation of patients affected by inflammatory bowel disease potentially eligible for biological treatment in a real-world setting

BACKGROUND/AIMS

This analysis estimated the number of inflammatory bowel disease (IBD) patients presenting criteria of eligibility for biological therapies in an Italian real-world setting.

METHODS

An observational analysis was performed on administrative databases of a sample of Local Health Units, covering 11.3% of the national population. Adult IBD patients (CD or UC) from 2010 to the end of data availability were included. Eligibility criteria for biologics were the following: Criterion A, steroid-refractory active disease; Criterion B, steroid-dependent patients; Criterion C, intolerance or contraindication to conventional therapies; Criterion D, severe relapsing disease; Criterion E (CD only), highly active CD disease and poor prognosis.

RESULTS

Of 26,781 IBD patient identified, 18,264 (68.2%) were treated: 3,125 (11.7%) with biologics and 15,139 (56.5%) non-biotreated. Among non-biotreated, 7,651 (28.6%) met at least one eligibility criterion for biologics, with criterion B (steroid-dependence) and criterion D (relapse) as the most represented (58-27% and 56-76%, respectively). Data reportioned to the Italian population estimated 67,635 patients as potentially eligible for biologics.

CONCLUSIONS

This real-world analysis showed a trend towards undertreatment with biologics in IBD patients with 28.6% being potentially eligible, suggesting that an unmet medical need still exists among the Italian general clinical practice for IBD management.

Personalized Treatment for Crohn's Disease: Current Approaches and Future Directions

Crohn's disease is a complex, relapsing and remitting inflammatory disorder of the gastrointestinal tract with a variable disease course. While the treatment options for Crohn's disease have dramatically increased over the past two decades, predicting individual patient response to treatment remains a challenge. As a result, patients often cycle through multiple different therapies before finding an effective treatment which can lead to disease complications, increased costs, and decreased quality of life. Recently, there has been increased emphasis on personalized medicine in Crohn's disease to identify individual patients who require early advanced therapy to prevent complications of their disease. In this review, we summarize our current approach to management of Crohn's disease by identifying risk factors for severe or disabling disease and tailoring individual treatments to patient-specific goals. Lastly, we outline our knowledge gaps in implementing personalized Crohn's disease treatment and describe the future directions in precision medicine.

Deep remission improves the quality of life of patients with Crohn's disease and anoperineal fistula treated with darvadstrocel: results of a French pilot study

BACKGROUND

The injection of allogeneic adipose tissue-derived mesenchymal stem cells (MSC) into anal fistulas in patients with Crohn's disease has never been evaluated in "real-life" conditions in France.

METHODS

We prospectively studied the first patients receiving MSC injections at our center and undergoing 12 months of follow-up. The primary endpoint was the clinical and radiological response rate. The secondary endpoints were symptomatic efficacy, safety, anal continence, quality of life (Crohn's anal fistula-quality of life scale, CAF-QoL), and predictive factors of success.

RESULTS

We included 27 consecutive patients. The complete clinical and radiological response rates at M12 were 51.9% and 50%, respectively. The combined complete clinical-radiological response (deep remission) rate was 34.6%. No major adverse effects or changes in anal continence were reported. The perianal disease activity index decreased from 6.4 to 1.6 (p < 0.001) for all patients. The CAF-QoL score also decreased from 54.0 to 25.5 (p < 0.001). At the end of the study, M12, the CAF-QoL score was significantly lower only in patients with a complete combined clinical-radiological response relative to those without a complete clinical-radiological response (15.0 versus 32.8, p = 0.01). Having a multibranching fistula and infliximab treatment were associated with a combined complete clinical-radiological response.

CONCLUSIONS

This study confirms reported efficacy data for the injection of MSC for complex anal fistulas in Crohn's disease. It also shows a positive impact on the quality of life of patients, particularly those for whom a combined clinical-radiological response was achieved.

Anastomotic Configuration and Temporary Diverting Ileostomy Do Not Increase Risk of Anastomotic Stricture in Postoperative Crohn's Disease

INTRODUCTION

Surgical management of Crohn's disease (CD) is common. Postoperative complications include anastomotic stricturing (AS). The natural history and risk factors for AS have not been elucidated.

METHODS

A retrospective cohort study of patients with CD who underwent ileocolonic resection (ICR) with ≥1 postoperative ileocolonoscopy between 2009 and 2020. Postoperative ileocolonoscopies with corresponding cross-sectional imaging were evaluated for evidence of AS without neoterminal ileal extension. Severity of AS and endoscopic intervention at time of detection were collected. Primary outcome was development of AS. Secondary outcome was time to AS detection.

RESULTS

A total of 602 adult patients with CD underwent ICR with postoperative ileocolonoscopy. Of these, 426 had primary anastomosis, and 136 had temporary diversion at time of ICR. Anastomotic configuration consisted of 308 side-to-side, 148 end-to-side, and 136 end-to-end. One hundred ten (18.3%) patients developed AS with median time of 3.2 years to AS detection. AS severity at time of detection was associated with need for repeat surgical resection for AS. On multivariable Cox proportional hazard regression, anastomotic configuration and temporary diversion were not associated with risk of or time to AS. Preoperative stricturing disease was associated with decreased time to AS (adjusted hazard ratio 1.8; P = 0.049). Endoscopic ileal recurrence before AS was not associated with subsequent AS detection.

DISCUSSION

AS is a relatively common postoperative CD complication. Patients with previous stricturing disease behavior are at increased risk of AS. Anastomotic configuration, temporary diversion, and ileal CD recurrence do not increase risk of AS. Early detection and intervention for AS may help prevent progression to repeat ICR.

Precision medicine in inflammatory bowel disease

Inflammatory bowel disease (IBD) is an incurable disease characterized by remission-relapse cycles throughout its course. Both Crohn's disease (CD) and ulcerative colitis (UC), the two main forms of IBD, exhibit tendency to develop complications and substantial heterogeneity in terms of frequency and severity of relapse, thus posing great challenges to the clinical management for IBD. Current treatment strategies are effective in different ways in induction and maintenance therapies for IBD. Recent advances in studies of genetics, pharmacogenetics, proteomics and microbiome provide a strong driving force for identifying molecular markers of prognosis and treatment response, which should help clinicians manage IBD patients more effectively, and then, improve clinical outcomes and reduce treatment costs of patients. In this review, we summarize and discuss precision medicine in IBD, focusing on predictive markers of disease course and treatment response, and monitoring indices during therapeutic drug monitoring.

Prognostic modelling in IBD

In the ideal world prognostication or predicting disease course in any chronic condition would allow the clinician to anticipate disease behaviour, providing crucial information for the patient and data regarding best use of resources. Prognostication also allows an understanding of likely response to treatment and the risk of adverse effects of a treatment leading to withdrawal in any individual patient. Therefore, the ability to predict outcomes from the onset of disease is the key step to developing precision personalised medicine, which is the design of medical care to optimise efficiency or therapeutic benefit based on careful profiling of patients. An important corollary is to prevent unnecessary healthcare costs. This paper outlines currently available predictors of disease outcome in IBD and looks to the future which will involve the use of artificial intelligence to interrogate big data derived from various important 'omes' to tease out a more holistic approach to IBD.

Small molecule modulators of immune pattern recognition receptors

Pattern recognition receptors (PRRs) represent a re-emerging class of therapeutic targets for vaccine adjuvants, inflammatory diseases and cancer. In this review article, we summarize exciting developments in discovery and characterization of small molecule PRR modulators, focusing on Toll-like receptors (TLRs), NOD-like receptors (NLRs) and the cGAS-STING pathway. We also highlight PRRs that are currently lacking small molecule modulators and opportunities for chemical biology and therapeutic discovery.

Allogenic stem cells for Crohn's anal fistulas: Treating early improves the deep remission rate

AIM

The aim of this study was to evaluate the real-life clinical and radiological efficacy of darvadstrocel injection into complex perianal fistulas in Crohn's disease. Secondary endpoints were to assess symptomatic efficacy, adverse effects and factors associated with complete combined clinical-radiological response (deep remission).

METHODS

After marketing the product in France, all first patients treated consecutively were included. A complete clinical response was defined by a complete closure of all external openings with no discharge on pressure. A complete radiological response (MRI), evaluated at least after six months of follow-up, was defined by a completely fibrotic sequela without abscess. A deep remission was defined as the association of a complete clinical response with a complete radiological response.

RESULTS

A total of 43 patients were included (M/F: 22/21, median age 37 [26-45] years). The fistulas were already drained with seton(s) and were on biologic treatment. After a median follow-up of 383 (359-505) days, 28 (65%) patients showed a clinical response (22 complete and 6 partial) and 16 (37%) achieved a deep remission. The Perineal Disease Activity Index decreased significantly after treatment: 39 (91%) patients reported symptomatic improvement in terms of discharge, pain, and induration, and 28 (65%) no longer had any perineal symptoms. No severe adverse events were reported. A short history of Crohn's disease <3 years was significantly associated with deep remission (OD 4.5 [1.0-19.1], p = 0.04).

CONCLUSION

Darvadstrocel injection resulted in a clinical response for two thirds of patients and deep remission for one third. A shorter duration of Crohn's disease was associated with deep remission.

Crohn's Disease: Basic Characteristics of the Disease, Diagnostic Methods, the Role of Biomarkers, and Analysis of Metalloproteinases: A Review

Crohn's disease is a chronic inflammatory bowel disease that affects the ileum and/or large intestine. At the same time, it can also affect any other part of the human body, i.e., from the mouth to the anus. In Crohn's disease, the physiology and functioning of the epithelial barrier are inhibited due to the correlation of various factors, such as the environment, genetic susceptibility or intestinal microbiota. The symptoms are very troublesome and cause a significant reduction in quality of life, sometimes occurring with paralyzing permanent damage to the digestive tract, requiring enteral or parenteral nutrition throughout life. In order to make a proper and accurate diagnosis, an appropriately selected diagnostic path in a given clinical entity is necessary. Standard diagnostic methods are: laboratory examination, histopathological examination, endoscopic examination, X-ray, computed tomography, ultrasound examination and magnetic resonance imaging. Medical biology and the analysis of metalloproteinases have also proved helpful in diagnosing changes occurring as a result of Crohn's disease. Here we provide a thorough review of the latest reports on Crohn's disease and its genetic conditions, symptoms, morphology, diagnosis (including the analysis of Crohn's disease biomarkers, i.e., metalloproteinases) and treatment.

Difficult-to-treat inflammatory bowel disease: results from an international consensus meeting

Many patients with inflammatory bowel disease (IBD) have persistent symptoms and disease activity despite the best available medical or surgical treatments. These patients are commonly referred to as having difficult-to-treat IBD and need additional therapeutic strategies. However, the absence of standard definitions has impeded clinical research efforts and comparisons of data. Under the guidance of the endpoints cluster of the International Organization for the Study of Inflammatory Bowel Disease, we held a consensus meeting to propose a common operative definition for difficult-to-treat IBD. 16 participants from 12 countries voted on 20 statements covering various elements of difficult-to-treat IBD, such as failure of medical and surgical treatments, disease phenotypes, and specific complaints from patients. "Agreement" was defined as at least 75% consensus. The group agreed that difficult-to-treat IBD is defined by the failure of biologics and advanced small molecules with at least two different mechanisms of action, or postoperative recurrence of Crohn's disease after two surgical resections in adults, or one in children. In addition, chronic antibiotic-refractory pouchitis, complex perianal disease, and comorbid psychosocial complications that impair disease management also qualified as difficult-to-treat IBD. Adoption of these criteria could serve to standardise reporting, guide enrolment in clinical trials, and help identify candidates for enhanced treatment strategies.

Natural History of Anal Ulcerations in Pediatric-Onset Crohn's Disease: Long-Term Follow-Up of a Population-Based Study

INTRODUCTION

Anal ulcerations are frequently observed in Crohn's disease (CD). However, their natural history remains poorly known, especially in pediatric-onset CD.

METHODS

All patients with a diagnosis of CD before the age of 17 years between 1988 and 2011 within the population-based registry EPIMAD were followed retrospectively until 2013. At diagnosis and during follow-up, the clinical and therapeutic features of perianal disease were recorded. An adjusted time-dependent Cox model was used to evaluate the risk of evolution of anal ulcerations toward suppurative lesions.

RESULTS

Among the 1,005 included patients (females, 450 [44.8%]; median age at diagnosis 14.4 years [interquartile range 12.0-16.1]), 257 (25.6%) had an anal ulceration at diagnosis. Cumulative incidence of anal ulceration at 5 and 10 years from diagnosis was 38.4% (95% confidence interval [CI] 35.2-41.4) and 44.0% (95% CI 40.5-47.2), respectively. In multivariable analysis, the presence of extraintestinal manifestations (hazard ratio [HR] 1.46, 95% CI 1.19-1.80, P = 0.0003) and upper digestive location (HR 1.51, 95% CI 1.23-1.86, P < 0.0001) at diagnosis were associated with the occurrence of anal ulceration. Conversely, ileal location (L1) was associated with a lower risk of anal ulceration (L2 vs L1 HR 1.51, 95% CI 1.11-2.06, P = 0.0087; L3 vs L1 HR 1.42, 95% CI 1.08-1.85, P = 0.0116). The risk of fistulizing perianal CD (pCD) was doubled in patients with a history of anal ulceration (HR 2.00, 95% CI 1.45-2.74, P < 0.0001). Among the 352 patients with at least 1 episode of anal ulceration without history of fistulizing pCD, 82 (23.3%) developed fistulizing pCD after a median follow-up of 5.7 years (interquartile range 2.8-10.6). In these patients with anal ulceration, the diagnostic period (pre vs biologic era), exposure to immunosuppressants, and/or anti-tumor necrosis factor did not influence the risk of secondary anoperineal suppuration.

DISCUSSION

Anal ulceration is frequent in pediatric-onset CD, with nearly half of patients presenting with at least 1 episode after 10 years of evolution. Fistulizing pCD is twice as frequent in patients with present or past anal ulceration.

Choosing the Right Therapy at the Right Time for Pediatric Inflammatory Bowel Disease: Does Sequence Matter

Despite the enlarging therapeutic armamentarium, IBD is still plagued by a therapeutic ceiling. Precision medicine, with the selection of the "rights," may present a solution, and this review will discuss the critical process of pairing the right patient with right therapy at the right time. Firstly, the review will discuss the shift to and evidence behind early effective therapy. Then, it delves into promising future strategies of patient profiling to identify a patients' biological pathway(s) and prognosis. Finally, the review lays out practical considerations that drive treatment selection, particularly the impact of the therapeutic sequence.

The Risk of Developing Disabling Crohn's Disease: Validation of a Clinical Prediction Rule to Improve Treatment Decision Making

BACKGROUND

Crohn's disease (CD) is characterized by the development of complications over the course of the disease. It is crucial to identify predictive factors of disabling disease, in order to target patients for early intervention. We evaluated risk factors of disabling CD and developed a prognostic model.

METHODS

In total, 511 CD patients were retrospectively analyzed. Univariate and multivariate logistic regression analyses were used to identify demographic, clinical, and biological risk factors. A predictive nomogram model was developed in a subgroup of patients with noncomplicated CD (inflammatory pattern and no perianal disease).

RESULTS

The rate of disabling CD within 5 years after diagnosis was 74.6%. Disabling disease was associated with gender, location of disease, requirement of steroids for the first flare, and perianal lesions. In the subgroup of patients (310) with noncomplicated CD, the rate of disabling CD was 80%. In the multivariate analysis age at onset <40 years (OR = 3.46, 95% confidence interval [CI] = 1.52-7.90), extensive disease (L3/L4) (OR = 2.67, 95% CI = 1.18-6.06), smoking habit (OR = 2.09, 95% CI = 1.03-4.27), requirement of steroids at the first flare (OR = 2.20, 95% CI = 1.09-4.45), and albumin (OR = 0.59, 95% CI = 0.36-0.96) were associated with development of disabling disease. The developed predictive nomogram based on these factors presented good discrimination, with an area under the receiver operating characteristic curve of 0.723 (95% CI: 0.670-0.830).

CONCLUSION

We identified predictive factors of disabling CD and developed an easy-to-use prognostic model that may be used in clinical practice to help identify patients at high risk and address treatment effectively.

Diagnosis and Clinical Features of Perianal Lesions in Newly Diagnosed Crohn's Disease: Subgroup Analysis from Inception Cohort Registry Study of Patients with Crohn's Disease (iCREST-CD)

BACKGROUND AND AIMS

Perianal lesion is a refractory phenotype of Crohn's disease [CD] with significantly diminished quality of life. We evaluated the clinical characteristics of perianal lesions in newly diagnosed CD patients and the impact of perianal lesions on the quality of life in Japanese patients with CD.

METHODS

Patients newly diagnosed with CD after June 2016 were included between December 2018 and June 2020 from the Inception Cohort Registry Study of Patients with CD [iCREST-CD].

RESULTS

Perianal lesions were present in 324 [48.2%] of 672 patients with newly diagnosed CD; 71.9% [233/324] were male. The prevalence of perianal lesions was higher in patients aged <40 years vs ≥40 years, and it decreased with age. Perianal fistula [59.9%] and abscess [30.6%] were the most common perianal lesions. In multivariate analyses, male sex, age <40 years and ileocolonic disease location were significantly associated with a high prevalence of perianal lesions, whereas stricturing behaviour and alcohol intake were associated with low prevalence. Fatigue was more frequent [33.3% vs 21.6%] while work productivity and activity impairment-work time missed [36.3% vs 29.5%] and activity impairment [51.9% vs 41.1%] were numerically higher in patients with than those without perianal lesions.

CONCLUSIONS

At the time of CD diagnosis, approximately half of the patients had perianal lesions; perianal abscesses and perianal fistulas were the most common. Young age, male sex, disease location and behaviour were significantly associated with the presence of perianal lesions. The presence of perianal lesion was associated with fatigue and impairment of daily activities.

CLINICAL TRIALS REGISTRY

University Hospital Medical Information Network Clinical Trials Registry System [UMIN-CTR, UMIN000032237].

Evaluation of Albumin, Transferrin and Transthyretin in Inflammatory Bowel Disease Patients as Disease Activity and Nutritional Status Biomarkers

Inflammatory bowel disease (IBD), which includes Crohn's disease (CD) and ulcerative colitis (UC), is often accompanied by malnutrition that manifests itself as nutrient deficiencies and body mass loss or deficit. The purpose of this study is to evaluate the utility of albumin, transferrin and transthyretin levels in the assessment of nutritional status and IBD activity. The case-control study included 82 IBD patients. The serum concentrations of albumin, transferrin and transthyretine were determined by a quantitative sandwich enzyme-linked immunosorbent assay (ELISA). Significantly lower median concentrations of albumin were found in the IBD patients vs. controls and in CD patients compared to the UC patients. Significantly higher median transthyretin concentrations were found in the IBD patients compared to the healthy subjects. There were no significant differences in median transferrin concentrations between the IBD patients and the healthy subjects. Significantly higher albumin levels were found in IBD patients in remission compared to patients with moderate and severe exacerbation of IBD symptoms. There were no significant differences in the median transferrin or transthyretin levels in patients with IBD depending on disease activity. No differences were identified in the median transferrin or transthyretin levels in the IBD patients according to nutritional status. The median albumin concentrations in the IBD subjects were significantly higher in patients with normal body fat, normal BMI and normal waist circumferences compared to those with an abnormal nutritional status. The albumin levels reflect both nutritional status and disease activity and therefore cannot be considered a prognostic marker of malnutrition in IBD. As regards the utility of transferrin and transthyretin as markers of activity and nutritional status in IBD patients, further studies are required.

Symptoms of anxiety and depression associated with steroid efficacy and clinical outcomes in patients with inflammatory bowel disease

Background

Anxiety and depression symptoms are very common in patients with inflammatory bowel disease (IBD). We aimed to explore the impact of anxiety and depression on the efficacy of medications, as well as IBD-related poor outcomes.

Method

This was a prospective longitudinal observational study. Hospital Anxiety and Depression Scale was used to assess anxiety and depression symptoms. Logistic regression analyses were used to assess the association between anxiety/depression and the response to different medications. Kaplan-Meier survival analysis and Cox regression model were applied to analyze the relationship between anxiety/depression and IBD-related poor outcomes, which were defined as urgent IBD-related hospitalization, IBD-related surgery, or death.

Results

A total of 325 IBD patients were enrolled, 118 of whom were treated with corticosteroids, 88 with azathioprine/6-mercaptopurine (AZA/6-MP), and 147 with anti-TNF agents. Anxiety/depression symptoms were found to be significantly related to steroid resistance, but independent of AZA/6-MP and anti-TNF agents nonresponse. There was a significant association between anxiety/depression symptoms and IBD-related poor outcomes. Coexisting with anxiety/depression symptoms was an independent influencing factor of steroid resistance and IBD-related poor outcomes.

Conclusion

IBD patients with anxiety/depression symptoms were at a higher risk of developing steroid resistance and IBD-related poor outcomes. Future studies are needed to explore whether interventions for anxiety and depression will improve their response to medications and change their prognosis.

Recent Advances and Potential Multi-Omics Approaches in the Early Phases of Inflammatory Bowel Disease

Inflammatory bowel disease leads to debilitating gastrointestinal symptoms and reduced quality of life, resulting in a significant burden on healthcare utilization and costs. Despite substantial advancements in diagnosis and treatment, there may still be considerable delays in diagnosing some patients. To reduce disease progression before the full disease spectrum appears and improve prognostic outcomes, several strategies have concentrated on early intervention and prevention. Recent evidence shows that initial immune response changes and endoscopic lesions may exist for years before diagnosis, implying the existence of a preclinical phase of inflammatory bowel disease comparable to findings in other immune-mediated disorders. In this review, we highlight the most relevant findings regarding preclinical inflammatory bowel disease and the prospective role of novel omics techniques in this field.

Postoperative Complications Are Associated With an Early and Increased Rate of Disease Recurrence After Surgery for Crohn's Disease

BACKGROUND

Several potential risk factors for Crohn's disease recurrence after surgery have been identified, including age at diagnosis, disease phenotype, and smoking. Despite the clinical relevance, few studies investigated the role of postoperative complications as a possible risk factor for disease recurrence.

OBJECTIVE

To investigate the association between postoperative complications and recurrence in Crohn's disease patients after primary ileocolic resection.

DESIGN

This was a retrospective case-control study.

SETTING

This study was conducted at 2 tertiary academic centers.

PATIENTS

We included 262 patients undergoing primary ileocolic resection for Crohn's disease between January 2008 and December 2018 and allocated the patients into recurrent (145) and nonrecurrent (117) groups according to endoscopic findings.

MAIN OUTCOME MEASURES

Postoperative complications were assessed as possible risk factors for endoscopic recurrence after surgery by univariable and multivariable analyses. The effect of postoperative complications on endoscopic and clinical recurrence was evaluated by Kaplan-Meier and Cox regression analyses.

RESULTS

On binary logistic regression analysis, smoking (OR = 1.84; 95% CI, 1.02-3.32; p = 0.04), penetrating phenotype (OR = 3.14; 95% CI, 1.58-6.22; p < 0.01), perianal disease (OR = 4.03; 95% CI, 1.75-9.25; p = 0.001), and postoperative complications (OR = 2.23; 95% CI, 1.19-4.17; p = 0.01) were found to be independent risk factors for endoscopic recurrence. Postoperative complications (HR = 1.45; 95% CI, 1.02-2.05; p = 0.03) and penetrating disease (HR = 1.73; 95% CI, 1.24-2.40; p = 0.001) significantly reduced the time to endoscopic recurrence; postoperative complications (HR = 1.6; 95% CI, 1.02-2.88; p = 0.04) and penetrating disease (HR = 207.10; 95% CI, 88.41-542.370; p < 0.0001) significantly shortened the time to clinical recurrence.

LIMITATIONS

This study was limited by its retrospective design.

CONCLUSIONS

Postoperative complications are independent risk factors for endoscopic recurrence after primary surgery for Crohn's disease, affecting the rate and timing of endoscopic and clinical disease recurrence. See Video Abstract at http://links.lww.com/DCR/C48 .

LAS COMPLICACIONES POSOPERATORIAS ESTN ASOCIADAS CON UNA TASA TEMPRANA Y AUMENTADA DE RECURRENCIA DE LA ENFERMEDAD DESPUS DE LA CIRUGA PARA LA ENFERMEDAD DE CROHN

ANTECEDENTES: Se han identificado varios factores de riesgo potenciales para la recurrencia de la enfermedad de Crohn después de la cirugía, incluida la edad en el momento del diagnóstico, el fenotipo de la enfermedad y el tabaquismo. A pesar de la relevancia clínica, pocos estudios investigaron el papel de las complicaciones postoperatorias como posible factor de riesgo para la recurrencia de la enfermedad.OBJETIVO: Investigar la asociación entre las complicaciones postoperatorias y la recurrencia en pacientes con enfermedad de Crohn después de la resección ileocólica primaria.DISEÑO: Este fue un estudio retrospectivo de casos y controles.AJUSTE: Este estudio se realizó en dos centros académicos terciarios.PACIENTES: Incluimos 262 pacientes sometidos a resección ileocólica primaria por enfermedad de Crohn entre Enero de 2008 y Diciembre de 2018 y los asignamos en grupos recurrentes (145) y no recurrentes (117) según los hallazgos endoscópicos.PRINCIPALES MEDIDAS DE RESULTADO: Las complicaciones posoperatorias se evaluaron como posibles factores de riesgo de recurrencia endoscópica después de la cirugía mediante análisis univariable y multivariable. El efecto de las complicaciones posoperatorias sobre la recurrencia endoscópica y clínica se evaluó mediante análisis de regresión de Kaplan-Meier y Cox.RESULTADOS: En el análisis, tabaquismo (OR = 1,84; IC 95%: 1,02-3,32; p = 0,04), fenotipo penetrante (OR = 3,14; IC 95%: 1,58-6,22; p < 0,01), enfermedad perianal (OR = 4,03; IC 95%: 1,75-9,25; p = 0,001) y las complicaciones postoperatorias (OR = 2,23; IC 95%: 1,19-4,17; p = 0,01) fueron factores de riesgo independientes para la recurrencia endoscópica. Las complicaciones posoperatorias (HR = 1,45; IC 95%: 1,02-2,05; p = 0,03) y la enfermedad penetrante (HR = 1,73; IC 95%: 1,24-2,40; p = 0,001) redujeron significativamente el tiempo hasta la recurrencia endoscópica; las complicaciones posoperatorias (HR= 1,6; IC 95%: 1,02-2,88; p = 0,04) y la enfermedad penetrante (HR = 207,10; IC 95%: 88,41-542,37; p < 0,0001) acortaron significativamente el tiempo hasta la recurrencia clínica.LIMITACIONES: Este estudio estuvo limitado por su diseño retrospectivo.CONCLUSIONES: Las complicaciones postoperatorias son factores de riesgo independientes para la recurrencia endoscópica después de la cirugía primaria para la enfermedad de Crohn, lo que afecta la tasa y el momento de la recurrencia endoscópica y clínica de la enfermedad. Consulte el Video Resumen en http://links.lww.com/DCR/C48 . (Traducción-Dr. Yesenia Rojas-Khalil ).

Long-term Outcomes and Factors Predicting Outcome of IPAA When Used Intentionally for Well-Defined Crohn's Disease

BACKGROUND

Crohn's disease is considered a contraindication for IPAA. In our prior study, when IPAA was used intentionally for well-defined Crohn's disease, we found a high incidence of recurrent disease with a low incidence of pouch failure.

OBJECTIVE

This study aimed to replicate these findings in a larger cohort over a longer period.

DESIGN

Retrospective review of a prospective IBD registry.

SETTINGS

Large IBD referral center.

PATIENTS

Patients with preoperative colorectal Crohn's disease requiring surgery were included in the study.

INTERVENTION

IPAA.

MAIN OUTCOME MEASURES

Long-term Crohn's disease recurrence, pouch failure, and pouch function.

RESULTS

Forty-six patients were identified. Crohn's disease was diagnosed on the basis of perianal disease (n = 18; 39%), small-bowel disease (n = 16; 35%), noncaseating granuloma (n = 10; 22%), and discontinuous inflammation (colorectal skip lesions) (n = 11; 24%). After a median follow-up of 93 (7-291) months, 22 patients (48%) developed recurrent Crohn's disease based on afferent limb disease (n = 14; 30%) or pouch fistulizing disease (n = 8; 18%). Only 4 patients (9%) developed pouch failure. No clinical factor was associated with Crohn's disease recurrence. Young age at the time of surgery and short duration of disease before IPAA were associated with pouch fistula recurrence ( p = 0.003 and p = 0.03, respectively). Most patients (86%) reported excellent continence, with no urgency (67%) and median stool frequency of 6 (range, 3-9) per day.

LIMITATION

Retrospective nature and relatively small sample size.

CONCLUSION

This largest reported series examining the intentional use of IPAA in Crohn's disease showed a high (48%) incidence of postoperative Crohn's disease with a low (9%) incidence of pouch failure. Young age and short disease course before surgery were risk factors for poor outcomes. Highly motivated patients with colorectal Crohn's disease may consider IPAA and avoid a definitive ileostomy. See Video Abstract at http://links.lww.com/DCR/C171 .

RESULTADOS A LARGO PLAZO Y FACTORES PREDICTORES DE RESULTADOS DE LA ANASTOMOSIS ILEOANAL CON RESERVORIO CUANDO SE USA INTENCIONALMENTE PARA LA ENFERMEDAD DE CROHN BIEN DEFINIDA

ANTECEDENTES: La enfermedad de Crohn (EC) se considera una contraindicación para la anastomosis ileoanal con reservorio (IPAA). Nuestro estudio previo de IPAA cuando fue usada intencionalmente para EC bien definida mostró una alta incidencia de enfermedad recurrente con una baja incidencia de falla del reservorio.OBJETIVO: Replicar estos hallazgos en una cohorte más grande durante un período más largo.DISEÑO: Revisión retrospectiva de una base de datos prospectiva de enfermedad inflamatoria intestinal.ESCENARIO: Un centro grande de referencia de EII.PACIENTES: EC colorrectal preoperatoria con necesidad de tratamiento quirúrgico.INTERVENCIÓN: Anastomosis ileoanal con reservorio.RESULTADOS PRINCIPALES: Recurrencia de EC a largo plazo, falla del reservorio y función del reservorio.RESULTADOS: Cuarenta y seis pacientes fueron identificados. El diagnóstico de EC se basó en enfermedad perianal (n = 18; 39%), enfermedad del intestino delgado (n = 16; 35%), granuloma no caseificante (n = 10; 22%) e inflamación discontinua (lesiones salteadas colorrectales) (n = 11; 24%). Después de una mediana de seguimiento de 93 (7-291) meses, 22 (48 %) pacientes desarrollaron EC recurrente debido a enfermedad del asa aferente (n = 14; 30%) o enfermedad fistulizante del reservorio (n = 8; 18%). Solo 4 (9%) pacientes desarrollaron falla del reservorio. Ningún factor clínico se asoció con la recurrencia de EC. La edad joven en el momento de la cirugía y la corta duración de la enfermedad antes de IPAA se asociaron con la recurrencia de la fístula del reservorio ( p = 0.003 y p = 0.03, respectivamente). El recuento de plaquetas preoperatorio más alto fue la única característica clínica significativamente asociada con el fracaso del reservorio ( p = 0.02). La mayoría de los pacientes (86%) reportaron una continencia excelente, sin urgencia (67%) y una mediana de frecuencia evacuatoria de 6 (rango, 3-9) por día.LIMITACIONES: Naturaleza retrospectiva y tamaño de muestra relativamente pequeño.CONCLUSIÓN: Esta serie, la más grande reportada que examina el uso intencional de IPAA en la EC mostró una incidencia alta (48Rectal Cancer: Clinical and Molecular Predictors of a Complete Response to Total Neoadjuvant Therapy%) de EC posoperatoria con una incidencia baja (9%) de falla del reservorio. La edad joven y el curso corto de la enfermedad antes de la cirugía fueron factores de riesgo para pobres resultados. Pacientes altamente motivados con EC colorrectal pueden considerar una IPAA y evitar una ileostomía permanente. Consulte Video Resumen en http://links.lww.com/DCR/C171 . (Traducción-Dr. Jorge Silva Velazco ).

Ileocecal valve that cannot be intubated in Crohn's disease: is this a sign of poor prognosis?

BACKGROUND

In Crohn's disease (CD), the inability to intubate the ileocecal valve during colonoscopy may be associated with a poor disease prognosis. In this study, we aimed to compare the long-term outcomes of CD patients with and without ileocecal valve intubation during colonoscopy to assess its value as a prognostic parameter.

METHODS

This retrospective study involved CD patients with isolated ileal involvement who underwent colonoscopy between 1993 and 2022. We compared the basic characteristics and long-term clinical outcomes of two groups of patients: those with intubated and non-intubated ileocecal valves during colonoscopy.

RESULTS

Of the 155 participants, 97 (62.5%) patients' ileum could be intubated and 58 (37.5%) could not be intubated. The non-intubated group was younger at diagnosis (39 years versus 30.5 years, p = 0.002), but other baseline characteristics such as sex, smoking status, disease duration, perianal disease, and upper gastrointestinal involvements were similar. The non-intubated group had higher rates of steroid dependence (67.2% versus 46.4%; p = 0.012), biologic treatment (89.7% versus 58.8%; p < 0.001), CD-related hospitalization (81% versus 24.7%; p < 0.001), and major abdominal surgery (58.6% versus 15.5%; p < 0.001). In the logistic regression analysis, the positive predictors of successful ileum intubation were inflammatory type CD (OR: 14.821), high serum albumin level (OR: 5.919), and older age (OR: 1.069), while the negative predictors were stenosing (OR: 0.262) and penetrating (OR: 0.247) CD behavior.

CONCLUSIONS

In Crohn's disease patients with isolated ileal involvement, ileocecal valve cannot be intubated during colonoscopy may indicate the severity of the disease.

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.

Evaluation of a downstaging, bidirectional version of the Montreal classification of Crohn's disease: Analysis of 5-year follow-up data from the prospective BioCrohn study

OBJECTIVE

Under the assumption of irreversibility, the Montreal classification provides a unidirectional assessment of the complications and behaviour of Crohn's disease (CD) that does not allow for downstaging. We examined the use of a bidirectional Montreal classification system that can capture disease regression.

DESIGN

From the BioCrohn Registry, an inception cohort of patients with CD for ≤12 months duration was defined and followed up for 5-years. Cumulative probabilities for developing complications were estimated using the Kaplan-Meier method. Potential associations of explanatory variables with disease progression were estimated with Cox regression.

RESULTS

Among 393 incident CD patients (of whom 255 completed the entire follow-up), the 5-year cumulative probability of developing complications was 41.5% (15.6% and 25.9% for stricturing and penetrating complications respectively). Perianal disease (hazard ratio [95% confidence interval]: 8.45 [4.74-15.07]) and surgical resection of the intestine (2.71 [1.50-4.92]) in the very early phase of the disease were associated with a higher risk of developing a penetrating complication within the 5-year follow-up. The use of a bidirectional Montreal classification system which can account for disease regression demonstrated that 90% of patients exhibited inflammatory disease behaviour at 5 years, in contrast to 58%, if the hierarchical, unidirectional Montreal classification system was used.

CONCLUSION

An additional bidirectional disease behaviour assessment capturing reversed or fully controlled complications may provide a more realistic appraisal of the complexity and unmet needs of patients treated with advanced therapies.

Efficacy and safety of mesenchymal stem cells in the treatment of perianal fistulas in Crohn's disease: a meta-analysis of randomized controlled trials

OBJECTIVES

Local mesenchymal stem cell (MSC) therapy for perianal fistulas in Crohn's disease (CD) has yielded promising results, but it still remains controversial. In this study, we aimed to conduct a meta-analysis of randomized controlled trials (RCTs) to evaluate the efficacy and safety of MSC therapy for perianal CD (pCD).

METHODS

RCTs reporting MSC therapy for perianal fistulas in CD were searched and included. The effectiveness and safety data were analyzed using RevMan 5.3.

RESULTS

A total of 7 RCTs were included in this meta-analysis. The analysis showed that patients receiving MSC therapy presented a higher healing rate (HR) of pCD than those in the control group (odds ratio (OR)=1.42; 95% confidence interval (CI) 1.18, 1.71; P=0.0002). Compared with placebo (saline solution), MSC therapy improved the HR of pCD (OR=1.85; 95% CI 1.32, 2.60; P=0.0004). MSC therapy showed significant long-term efficacy (OR=1.36; P=0.009; 95% CI 1.08, 1.71). When MRI was used to evaluate fistula healing, a pooled analysis showed that the MSC group achieved a higher HR than the control group (OR=1.95; 95% CI 1.33, 2.87; P=0.0007). Allogeneic MSC therapy was superior to the control treatment in improving HR (OR = 1.97; 95% CI 1.40, 2.75; P<0.001). Furthermore, no significant differences were observed between MSC therapy and placebo in terms of adverse events (AEs) (OR = 1.16; 95% CI 0.76, 1.76; P = 0.48). None of the AEs were judged to be related to MSC treatment.

CONCLUSIONS

This meta-analysis of RCTs provided evidence that local MSC injection is safe and efficacious for perianal fistulas in CD. In addition, this treatment has favorable long-term efficacy and safety profiles.