Prediction of complicated disease course for children newly diagnosed with Crohn's disease: a multicentre inception cohort study

Circulating and Magnetic Resonance Imaging Biomarkers of Intestinal Fibrosis in Small Bowel Crohn's Disease

BACKGROUND

We previously identified circulating and MRI biomarkers associated with the surgical management of Crohn's disease (CD). Here we tested associations between these biomarkers and ileal resection inflammation and collagen content.

METHODS

Fifty CD patients undergoing ileal resection were prospectively enrolled at 4 centers. Circulating CD64, extracellular matrix protein 1 (ECM1), GM-CSF autoantibodies (GM-CSF Ab), and fecal calprotectin were measured by ELISA. Ileal 3-dimensional magnetization transfer ratio (3D MTR), modified Look-Locker inversion recovery (MOLLI) T1 relaxation, diffusion-weighted intravoxel incoherent motion (IVIM), and the simplified magnetic resonance index of activity (sMaRIA) were measured by MRI. Ileal resection specimen acute inflammation was graded, and collagen content was measured quantitatively using second harmonic imaging microscopy. Associations between biomarkers and ileal collagen content were tested.

RESULTS

Median (interquartile range [IQR]) age was 19.5 (16-33) years. We observed an inverse relationship between ileal acute inflammation and collagen content (r = -0.39 [95% confidence interval {CI}: -0.61, -0.10], P = .008). Most patients (33 [66%]) received biologics, with no variation in collagen content with treatment exposures. In the univariate analysis, CD64, GM-CSF Ab, fecal calprotectin, and sMaRIA were positively associated with acute inflammation and negatively associated with collagen content (P < .1). The multivariable model for ileal collagen content (R2 = 0.31 [95% CI: 0.11, 0.52]) included log CD64 (β = -.27; P = .19), log ECM1 (β = .47; P = .06), log GM-CSF Ab (β = -.15; P = .01), IVIM f (β = .29, P = .10), and IVIM D* (β = 1.69, P = .13).

CONCLUSIONS

Clinically available and exploratory circulating and MRI biomarkers are associated with the degree of inflammation versus fibrosis in CD ileal resections. With further validation, these biomarkers may be used to guide medical and surgical decision-making for refractory CD.

Long-Term Outcome of Paediatric Crohn's Disease Patients With Deep Ulcerations at Diagnosis

AIM

Presence of deep ulcerations (DU) at diagnosis seems to be predictive of a more severe phenotype in adult Crohn's disease (CD). The aim of our study was to investigate if the presence of DU at diagnosis was associated with a more severe disease course over time in children.

METHODS

In this monocentric retrospective study, we analysed data from paediatric patients with a new diagnosis of CD from 2009 to 2017. Clinical, laboratory data, treatments and complications were recorded for each patient at diagnosis and at 1, 3 and 5 years of follow-up. Patients were compared according to the presence or absence of DU on colonoscopy.

RESULTS

Among the 116 patients included in the study, 52 patients had DU at diagnosis. Comparison showed an increased risk for patients with DU to develop abdominal abscesses (p = 0.045) and to experience more relapses (p = 0.013) at 1 year. At 3 and 5 years, there was no longer any difference between groups. The time from diagnosis to first anti-TNF alpha was shorter in DU patients.

CONCLUSION

The presence of DU at diagnosis is associated with more complications during the first year of follow-up but not after, due to a more active therapeutic management.

HLA DQA1*05 and Risk of Antitumor Necrosis Factor Treatment Failure and Anti-Drug Antibody Development in Children With Crohn's Disease

INTRODUCTION

Human leukocyte antigen (HLA) DQA1*05 has been associated with the development of anti-drug antibodies (ADA) to tumor necrosis factor antagonists (anti-TNFα) and treatment failure among adults with Crohn's disease (CD). However, findings from other studies have been inconsistent with limited pediatric data.

METHODS

We analyzed banked serum from patients with CD aged <21 years enrolled in clinical outcomes of Methotrexate Binary Therapy in practice, a multicenter, prospective randomized trial of anti-TNFα monotherapy vs combination with methotrexate. The primary outcome was a composite of factors indicative of treatment failure. The secondary outcome was ADA development.

RESULTS

A trend toward increased treatment failure among HLA DQA1*05-positive participants was not significant (hazard ratio 1.58, 95% confidence interval [CI] 0.95-2.62; P = 0.08). After stratification by HLA DQA1*05 and by methotrexate vs placebo, patients who were HLA DQA1*05 negative and assigned to methotrexate experienced less treatment failures than HLA DQA1*05-positive patients on placebo (hazard ratio 0.31, 95% CI 0.13-0.70; P = 0.005). A trend toward increased ADA development among HLA DQA1*05-positive participants was not significant (odds ratio 1.96, 95% CI 0.90-4.31, P = 0.09). After further stratification, HLA DQA1*05-negative participants assigned to methotrexate were less likely to develop ADA relative to HLA DQA1*05-positive patients on placebo (odds ratio 0.12, 95% CI 0.03-0.55; P = 0.008).

DISCUSSION

In a randomized trial of children with CD initiating anti-TNFα, 40% were HLA DQ-A1*05 positive, which was associated with a trend toward increased risk of both treatment failure and ADA. These risks were mitigated, but not eliminated, by adding oral methotrexate. HLA DQ-A1*05 is an important biomarker for prognosis and risk stratification.

Robustness of viral load over CD4 cell count in measuring the quality of life of people with HIV at second line regimen in Amhara region

Access to medication for people living with HIV in need is a global health priority. Monitoring the quality of life of people under treatment helps to optimize the resource allocated for the program. Therefore, the main objective of the current study was to assess the quality of life comparing viral load and CD4 cell count and factors affecting the variable of interest among HIV-positive people under the second-line regimens. A hospital-based retrospective secondary data were used for the current investigation. The study was conducted in governmental hospitals in Amhara region. ROC curve was used for comparing CD4 cell count and viral load in assessing the quality of life and its predictors. Among the participants in second-line regimen, about 18.3% of them had CD4 cell count < 200 cells/ml of blood and 49.4% of them had detectable/unsuppressed viral load. The result of ROC curve in the current study indicates that viral load was in favors of CD4 cell count in this regard. Among the predictors for quality of life, age of patients, level of CD4 cell count while transferring to second-line regimen, sex of patients, social discrimination, level of education of patients, functional status, adherence level, disclosure status of the disease, mental depression, existence of opportunistic infections and residence area had significant effect on the variable of interest (quality of life). Viral load was in favor of CD4 cell count in assessing the quality of people under treatment. Hence, a close follow ups of patients under treatment at second-line regimen using viral load assessment is highly recommended. Due attention should be given to patients with Unsuppressed HIV viral loads. Hence, awareness creation on how the quality of life be improved should be formulated for patients during visiting times. Knowledge of HIV transmission is also important to reduce the violence and discrimination against those HIV-positive adults to improve their health status. Experience sharing between medication adherent and non-adherent patients may encourage those non-adherent patients to get lessons from adherent patients.

Fecal Microbiome Reflects Disease State and Prognosis in Inflammatory Bowel Disease in an Adult Population-Based Inception Cohort

INTRODUCTION

We aimed to determine the diagnostic and prognostic potential of baseline microbiome profiling in inflammatory bowel disease (IBD).

METHODS

Participants with ulcerative colitis (UC), Crohn's disease (CD), suspected IBD, and non-IBD symptomatic controls were included in the prospective population-based cohort Inflammatory Bowel Disease in South-Eastern Norway III (third iteration) based on suspicion of IBD. The participants donated fecal samples that were analyzed with 16S rRNA sequencing. Disease course severity was evaluated at the 1-year follow-up. A stringent statistical consensus approach for differential abundance analysis with 3 different tools was applied, together with machine learning modeling.

RESULTS

A total of 1404 individuals were included, where n = 1229 samples from adults were used in the main analyses (n = 658 UC, n = 324 CD, n = 36 IBD-U, n = 67 suspected IBD, and n = 144 non-IBD symptomatic controls). Microbiome profiles were compared with biochemical markers in machine learning models to differentiate IBD from non-IBD symptomatic controls (area under the receiver operating curve [AUC] 0.75-0.79). For UC vs controls, integrating microbiome data with biochemical markers like fecal calprotectin mildly improved classification (AUC 0.83 to 0.86, P < .0001). Extensive differences in microbiome composition between UC and CD were identified, which could be quantified as an index of differentially abundant genera. This index was validated across published datasets from 3 continents. The UC-CD index discriminated between ileal and colonic CD (linear regression, P = .008) and between colonic CD and UC (P = .005), suggesting a location-dependent gradient. Microbiome profiles outperformed biochemical markers in predicting a severe disease course in UC (AUC 0.72 vs 0.65, P < .0001), even in those with a mild disease at baseline (AUC 0.66 vs 0.59, P < .0001).

CONCLUSIONS

Fecal microbiome profiling at baseline held limited potential to diagnose IBD from non-IBD compared with standard-of-care. However, microbiome shows promise for predicting future disease courses in UC.

Travel Time to Treating Center Is Associated With Diagnostic Delay in Pediatric Inflammatory Bowel Disease

BACKGROUND & AIMS

Delayed diagnosis of inflammatory bowel disease (IBD) leads to prolonged symptoms and worse long-term outcomes. We sought to evaluate whether race, ethnicity, disease type, and social factors are associated with delayed diagnosis of pediatric IBD.

METHODS

We performed a cross-sectional study of newly diagnosed pediatric patients with IBD at 22 United States sites from 2019 to 2022. Parents/guardians reported race, ethnicity, time between symptom onset and diagnosis, and other social determinants of health. Through bivariate and multivariable analyses using generalized estimating equations, we evaluated associations between these factors and diagnosis time defined as ≤60 days, 61 to 180 days, 181 to 365 days, and >365 days.

RESULTS

We enrolled 869 participants (mean age at diagnosis, 13.1 years; 52% male; 57% Crohn's disease [CD]; 34% ulcerative colitis [UC]; 8% Hispanic; 30% non-White). Overall, the mean time to diagnosis was 265.9 days. After adjustment, factors associated with longer diagnosis time included CD vs UC (odds ratio [OR], 2.6; 95% confidence interval [CI], 1.9-3.5), 2 or more other health conditions (OR, 1.7; 95% CI, 1.1-2.7), and longer travel time to clinic (>1 hour [OR, 1.7; 95% CI, 1.2-2.4], >2 hours (OR, 1.8; 95% CI, 1.2-2.9] each vs <30 minutes). There was no association with race, ethnicity, birth country, gender, parent education, household income, insurance type, health literacy, and health system distrust.

CONCLUSIONS

Consistent with prior literature, diagnostic delay is longer for CD than UC. Reassuringly, time to diagnosis is equitable across racioethnic groups. New models of diagnostic care are needed for communities affected by longer travel times.

Racial Disparities in Utilization of Medications and Disease Outcomes in Inflammatory Bowel Disease Patients

Background

Although traditionally associated with White European ancestry, inflammatory bowel disease (IBD) has increased among different races and ethnicities. Large studies conducted in the United States and Canada have identified more complex disease phenotypes among Black patients. Our study aimed to investigate disparities in IBD treatments and outcomes between Black and White patients in the United States.

Methods

Using the TriNetX database, adult IBD patients were divided into 2 groups based on race: Black and White patients with IBD, Crohn's disease (CD), or ulcerative colitis (UC). Medical therapy and disease outcomes were evaluated in both groups with 1:1 propensity-score matching. Methodologic limitations include the potential for missing data, lack of information on socioeconomic strata, and patient-level medication coverage plans.

Results

In comparison to White patients, Black patients with CD were less likely to receive advanced therapies; Adalimumab (adjusted odds ratio- aOR 0.89), Certolizumab (0.81), Vedolizumab (0.66), Ustekinumab (0.82), or Tofacitinib (0.58). Black patients with UC were less likely to receive advanced therapies; Adalimumab (0.83), Golimumab (0.62), Vedolizumab (0.69), Ustekinumab (0.73), or Tofacitinib (0.55). Black patients with IBD were at higher odds of utilizing corticosteroids (CD 1.18 and UC 1.20) and opioids (CD 1.26 and UC 1.09). Black patients with CD had higher rates of hospitalization (1.35) and perianal abscess (1.56), perianal fistula (1.28), and intestinal fistula (1.38). Black patients with UC had higher rates of hospitalization (1.29), Clostridioides difficile infection (1.11), and toxic megacolon (1.34).

Conclusions

There were racial disparities in IBD medical therapy and disease outcomes. Black IBD patients had lower treatment with advanced therapies, higher opioid and corticosteroid use, and higher IBD-related complications.

Microbiota in inflammatory bowel disease: mechanisms of disease and therapeutic opportunities

Perturbations in the intestinal microbiome are strongly linked to the pathogenesis of inflammatory bowel disease (IBD). Bacteria, fungi and viruses all make up part of a complex multi-kingdom community colonizing the gastrointestinal tract, often referred to as the gut microbiome. They can exert various effects on the host that can contribute to an inflammatory state. Advances in screening, multiomics and experimental approaches have revealed insights into host-microbiota interactions in IBD and have identified numerous mechanisms through which the microbiota and its metabolites can exert a major influence on the gastrointestinal tract. Looking into the future, the microbiome and microbiota-associated processes will be likely to provide unparalleled opportunities for novel diagnostic, therapeutic and diet-inspired solutions for the management of IBD through harnessing rationally designed microbial communities, powerful bacterial and fungal metabolites, individually or in combination, to foster intestinal health. In this Review, we examine the current understanding of the cross-kingdom gut microbiome in IBD, focusing on bacterial and fungal components and metabolites. We examine therapeutic and diagnostic opportunities, the microbial metabolism, immunity, neuroimmunology and microbiome-inspired interventions to link mechanisms of disease and identify novel research and therapeutic opportunities for IBD.

Biologics in the management of pediatric inflammatory bowel disease: When and what to choose

Pediatric inflammatory bowel disease (PIBD) is a chronic inflammatory disorder of the gastrointestinal tract, with rising global incidence and prevalence. Over the past two decades, biologics have added to the therapeutic armamentarium and revolutionized the approach to treatment of inflammatory bowel disease. The available biologics include monoclonal antibodies which target inflammatory cytokines (anti-tumor necrosis factor alpha, anti-interleukin 12/23) or recruitment of leucocytes to the gastrointestinal tract (anti-alpha4beta7 integrin) and small molecules (Janus kinase inhibitors, sphingosine 1-phosphate-inhibitors) which modify the proinflammatory signaling. Considering their potential disease-modifying ability, recent pediatric guidelines from the West have advocated upfront use of biologics in appropriate clinical scenarios as a top-down approach rather than the conventional step-up approach. Although real-world studies are available regarding the clinical efficacy of biologics in PIBD, there is paucity of long-term outcome and safety data in children. Also, little information is available about the best approach in the newly industrialized - developing countries where PIBD is rising but at the same time, infections are prevalent and resources are limited. In this review, we summarize the efficacy and safety profile of biologics and small molecule drugs and discuss the challenges in the management of PIBD, especially in the developing world, and future directions.

Early tumour necrosis factor antagonist treatment prevents perianal fistula development in children with Crohn's disease: post hoc analysis of the RISK study

BACKGROUND

One in three children with Crohn's disease develop perianal fistula complications (PFCs), among the most disturbing and difficult-to-treat disease-related complications. Retrospective evidence suggests PFCs may be preventable.

OBJECTIVE

We aimed to determine if early antitumour necrosis factor-alpha (anti-TNF⍺) therapy prevents PFC development in a well-characterised prospective cohort of paediatric patients with Crohn's disease who were free from PFC at enrolment.

DESIGN

RISK was a multicentre inception cohort of children newly diagnosed with Crohn's disease. We included all patients who had never experienced PFCs 30 days after study enrolment. We conducted nearest-neighbour propensity score-matched triad analyses. Matching was performed to balance patient characteristics across three mutually exclusive treatment groups based on therapy prior to either PFC development or the end of the observation period.

RESULTS

Among 873 patients without perianal fistula, 447 matched patients were included (149 per treatment group). The presence of non-penetrating perianal lesions (large skin tags, ulcers and/or fissures) was significantly associated with PFC development, with 4-fold greater odds of PFC (OR 4.08, 95% CI (95% CI) 1.70 to 9.78; p=0.0016). Early anti-TNF⍺ therapy was associated with an 82% decrease in the odds of PFC (OR 0.18, 95% CI 0.05 to 0.66; p=0.01). Among those with perianal lesions, anti-TNF⍺ therapy was associated with 94% reduced odds of PFC development (OR 0.055, 95% CI 0.006 to 0.50; p=0.010). No other treatment group was associated with reduced risk of PFC.

CONCLUSION

Early anti-TNF therapy prevents perianal fistula development, especially among patients at increased risk.

Prospective Evaluation of the Prediction Score for a Mild Course of Crohn's Disease (PreMiCC) in Newly Diagnosed Patients With Crohn's Disease: The PROGNOS Study

BACKGROUND AND AIMS

The course of Crohn's disease (CD) is highly variable. The Prospektive Evaluation eines Score zur Vorhersage eines milden Verlaufsbei neu diagnostizierten Morbus Crohn-Patienten in gastroenterologischen Fachpraxen (PROGNOS) study aimed to determine the frequency of a mild disease course and validate a proposed prediction score.

METHODS

The PROGNOS study is a prospective study of CD patients who were newly diagnosed and, except for 1 course of 5-aminosalicylic acid or steroids for ≤10 days, therapy-naïve. Among other predefined inclusion criteria, the initial diagnosis had to be made ≤6 weeks before enrollment. All inception cohort patients were diagnosed and screened consecutively in participating gastroenterology practices in Germany specialized in inflammatory bowel disease. All screened CD patients were scored and, if possible, included in the study for up to 5 years (NCT02193048).

RESULTS

A total of 201 CD patients were included in the study (43.3% male; mean age 33 years, mean follow-up 38 months). Altogether, 29.5% of the patients had a mild course at 36 months. Among those with a score ≤2, therapy escalation at 36 months was necessary for only 24.2%, whereas in the group with a score >2, therapy escalation was necessary for 70.2% of patients. In the Kaplan-Meier curve showing time to therapy escalation in the 2 groups, there was a pronounced and statistically significant divergence of the curves starting at 3 months and extending to 48 months (P < .001).

CONCLUSIONS

In this prospective study, about 30% of incident CD patients had a mild disease course. Our suggested PreMiCC (prediction score for a mild course of Crohn's disease) successfully predicted this.

Tissue factor-dependent colitogenic CD4+ T cell thrombogenicity is regulated by activated protein C signalling

Patients with inflammatory bowel disease (IBD) have an increased risk of venous thromboembolism (VTE), but the underlying mechanistic basis remains poorly defined. Here, we find that colitogenic CD4+ T cells express tissue factor (TF) and promote rapid TF-dependent plasma thrombin generation. TF+CD3+CD4+ T cells are present in both the colons of mice with experimental colitis and blood and colonic tissue from patients with IBD. Expression of genes involved in regulating coagulation, including Protein C (PC; encoded by PROC) and its receptor (PROCR), are dysregulated in IBD patient gut biopsy tissues. Moreover, activated PC signalling reduces the procoagulant activity mediated by TF+CD4+ T cells. Our data thus identify TF-induced, colitogenic T cell-mediated thrombogenicity, and also demonstrate a new function for activated PC signalling in regulating T cell thrombo-inflammatory activity.

Eight Cases of Pediatric Acute-Onset Neuropsychiatric Syndrome with Inflammatory Bowel Disease: Immunologic Intersections

INTRODUCTION

Pediatric acute-onset neuropsychiatric syndrome (PANS) is an immune-mediated disease characterized by abrupt onset neurobehavioral changes. Inflammatory bowel disease (IBD) includes ulcerative colitis (UC) and Crohn's disease (CD), chronic conditions characterized by gastrointestinal inflammation. We describe eight individuals with both PANS and IBD.

METHODS

All individuals with both IBD and PANS were identified from Stanford Immune Behavioral Health Clinic, Cedars-Sinai Medical Center Pediatric Inflammatory Bowel Disease Program, and Dartmouth Neuroimmune Psychiatric Disorders (NIPD) Clinic. Data were collected by chart review.

RESULTS

Eight cases of PANS with IBD were identified. Five were male. The mean age of onset was 9.3 years for PANS and 15.6 years for IBD. PANS preceded development of IBD in 7 of 8 cases by a mean of 8.4 years. Seven patients (88%) had a first-degree relative with an immune-mediated disease, including 5 with psoriasis or psoriatic arthritis. Five patients themselves had arthralgias or arthritis (63%). All 5 cases where PANS preceded IBD treatment sufficiently for analysis were free of major behavioral relapses after IBD was managed.

CONCLUSION

The triad of PANS, joint complaints, and family history of autoimmunity, including psoriasis, may represent a subset of PANS at heightened risk for IBD and additional immune-mediated disorders. For children with this triad, clinicians should have a low threshold to evaluate for gastrointestinal inflammation with biomarkers like hemoglobin, CRP, fecal calprotectin, and diagnostic endoscopy when indicated. PANS symptoms may improve with effective treatment of IBD. The high prevalence of joint complaints in our cohort and psoriasis in first-degree family members suggests this subset of PANS may share immune mechanisms with psoriasis and arthritis. Treatment strategies used in IBD and arthritis should be studied for potential application in PANS.

Eicosatetraynoic Acid Regulates Profibrotic Pathways in an Induced Pluripotent Stem Cell-Derived Macrophage-Human Intestinal Organoid Model of Crohn's Disease

BACKGROUND AND AIMS

We previously identified small molecules predicted to reverse an ileal gene signature for future Crohn's Disease (CD) strictures. Here we used a new human intestinal organoid (HIO) model system containing macrophages to test a lead candidate, eicosatetraynoic acid (ETYA).

METHODS

Induced pluripotent stem cell lines (iPSC) were derived from CD patients and differentiated into macrophages and HIOs. Macrophages and macrophage-HIO cocultures were exposed to lipopolysaccharide (LPS) with and without ETYA pretreatment. Cytospin and flow cytometry characterized macrophage morphology and activation markers, and RNA sequencing defined the global pattern of macrophage gene expression. TaqMan low-density array, Luminex multiplex assay, immunohistologic staining, and sirius red polarized light microscopy were performed to measure macrophage cytokine production and HIO profibrotic gene expression and collagen content.

RESULTS

Induced PSC-derived macrophages exhibited morphology similar to primary macrophages and expressed inflammatory macrophage cell surface markers including CD64 and CD68. LPS-stimulated macrophages expressed a global pattern of gene expression enriched in CD ileal inflammatory macrophages and matrisome-secreted products and produced cytokines and chemokines including CCL2, IL1B, and OSM implicated in refractory disease. ETYA suppressed CD64 abundance and profibrotic gene expression pathways in LPS-stimulated macrophages. Coculture of LPS-primed macrophages with HIO led to upregulation of fibroblast activation genes including ACTA2 and COL1A1, and an increase in HIO collagen content. ETYA pretreatment prevented profibrotic effects of LPS-primed macrophages.

CONCLUSIONS

ETYA inhibits profibrotic effects of LPS-primed macrophages upon cocultured HIO. This model may be used in future untargeted screens for small molecules to treat refractory CD.

Inflammatory Bowel Disease and Stroke: Exploring Hidden Vascular Risks

Inflammatory bowel disease (IBD), encompassing Crohn's disease and ulcerative colitis, is primarily known for its gastrointestinal manifestations. However, emerging evidence suggests a potential link between IBD and an increased risk of stroke, likely mediated by chronic systemic inflammation, endothelial dysfunction, and a prothrombotic state. Despite this growing recognition, the exact mechanisms and extent of this association remain unclear, highlighting a critical knowledge gap. This review aims to systematically analyze the association between IBD and stroke, exploring the underlying vascular mechanisms and identifying potential risk factors contributing to cerebrovascular events in IBD patients. A comprehensive literature search was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines across PubMed, Scopus, and Google Scholar using keywords such as "IBD," "Stroke," "Chronic inflammation," "Cerebrovascular risk," and "Gut-brain axis." After screening 150 studies and applying inclusion and exclusion criteria, six studies were included in the final synthesis. The findings suggest that chronic inflammation in IBD plays a key role in increasing stroke risk through endothelial dysfunction and a heightened prothrombotic state, with additional risk factors such as atrial fibrillation during active IBD flares further contributing to cerebrovascular events. While biologic therapies, including tumor necrosis factor (TNF)-alpha inhibitors, are effective in reducing systemic inflammation, their impact on mitigating stroke risk remains inconclusive. Given the potential role of IBD as an independent risk factor for stroke, a multidisciplinary approach to management is crucial. Addressing modifiable risk factors through pharmacologic interventions such as biologics, statins, and antiplatelet agents, alongside lifestyle modifications, could help reduce cerebrovascular complications in IBD patients. Further research is needed to explore personalized therapeutic strategies and establish clearer preventive guidelines for this at-risk population.

The microbial co-infection interaction network in apical periodontitis with sinus tracts

OBJECTIVES

This study aims to characterize the bacterial co-occurrence features and potential interactions associated with the presence of sinus tracts in apical periodontitis in a Chinese population by using 16S rRNA next-generation sequencing (NGS).

METHODS

Thirty-one samples from twenty-six patients were collected from root canals. Following the extraction of the bacterial DNA, the V3-V4 hypervariable regions of the 16S rRNA gene were sequenced. Compositional diversity, prominent taxa and co-occurrence network analysis were compared according to the presence or absence of sinus tracts.

RESULTS

The overall microbiota in two groups exhibited distinguished patterns. Actinomyces dominated in samples with sinus tracts while Prevotella was the most abundant in samples without sinus tracts. The major pathogens in sinus tracts exhibited a complex co-occurrence network, in which Pseudomonas formed a distinctive cluster with enriched abundance, and the extensive correlations centered on Desulfovibrio and Pseudoramibacter may suggest novel dependencies. In the network without sinus tracts, the Bacteroidetes and Firmicutes taxa presented close internal associations.

CONCLUSIONS

The sequencing results confirmed the complexity of the microbiota in AP. The presence of sinus tracts was associated with distinctive infective patterns and complicated microbial co-infection interaction networks. Further investigations should be adopted to elucidate the relationship between the novel interactions and disease progression.

CLINICAL SIGNIFICANCE

Exploring the microbial interactions leads to a better understanding of etiology of apical periodontitis. Utilizing next generation sequencing techniques, our research uncovered the bacterial community structure and observed co-infection networks associated with sinus tracts, providing potential insights for prognosis prediction and targeted therapeutics of persistent inflammation.

Prognostic value of magnetic resonance enterography for children with Crohn's disease: A multicenter, multireader study

BACKGROUND

Paediatric Inflammatory Crohn's MRE Index (PICMI) is a multi-point index of intestinal inflammation (mucosal and transmural) for children with CD. The present study aims to assess whether PICMI at diagnosis may predict the course of CD and to test the inter-reader agreement.

METHODS

CD children with a ≥ 1-year follow-up were retrospectively enrolled. Three radiologists calculated PICMI at diagnosis and association between PICMI and Paediatric Crohn's Disease Activity Index (PCDAI) and CD Endoscopic Index of Severity (CDEIS) was tested.

RESULTS

68 children (median age 13 years IQR: 11-14) with CD with PICMI at diagnosis: remission 6 (8.8 %), mild 29 (42.6 %), moderate 24 (35.3 %), severe 9 (13.2 %), were enrolled. PICMI score significantly correlated with PCDAI at diagnosis (p: 0.036). Steroid-free remission at 1, 3 and 5 years was comparable between PICMI groups (p: 0.606). Higher PICMI at diagnosis was associated with higher biologic introduction at 1 year: incidence rate ratio IRR: 2.17 (1.09-4.42); p = 0.019, 3-year IRR: 2.12 (1.15-3.96); p = 0.011, and 5 years: 2.21 (1.20-4.08); p = 0.007.

CONCLUSIONS

PICMI score is a reliable and almost reproducible index to score activity in children with CD. Children with higher PICMI scores of disease activity at diagnosis required more biologic treatment to achieve comparable rates of steroid-free remission if compared with lower PICMI scores.

Nutritional Habits in Crohn's Disease Onset and Management

Crohn's disease (CD)'s activation factors are still unclear. However, they are reported to involve an interaction between genetic susceptibility and unhealthy lifestyle factors like smoking, alcohol consumption, low physical activity, low BMI (<18.5 kg/m2), and probably unbalanced nutritional habits. Therefore, the aim of the present review is to demonstrate the possible effects of different nutritional habits, before the occurrence of the disease, as crucial factors for the inception of CD activation. The structure of the present narrative review was conducted following the instructions of the "Review Academy of Nutrition and Dietetics Checklist". It is well established that the consumption of specific foods and drinks, such as spicy and fatty foods, raw vegetables and fruits, dairy products, carbonated beverages, and coffee or tea, can provoke the exacerbation of CD symptoms. On the other hand, Mediterranean-oriented diets seem to provide an inverse association with the incidence of CD. Moreover, patients seem to have the knowledge to select foods that contribute to the remission of their symptoms. However, it is not clearly reported whether the onset of CD activation is due to lifelong unbalanced nutritional habits and their subsequent effect on gut microbiota secretion, which seems to be the gold standard for CD's investigation. Therefore, more future studies should record, examine, and compare the nutritional habits between patients with CD (immediately after the disease's diagnosis) and healthy populations in a lifelong manner, in order to reveal the possible influence of foods on CD onset.

Identification of circadian rhythm-related biomarkers and development of diagnostic models for Crohn's disease using machine learning algorithms

The global rise in Crohn's Disease (CD) incidence has intensified diagnostic challenges. This study identified circadian rhythm-related biomarkers for CD using datasets from the GEO database. Differentially expressed genes underwent Weighted Gene Co-Expression Network Analysis, with 49 hub genes intersected from GeneCards data. Diagnostic models were constructed using machine learning algorithms, and biologic therapy efficacy was predicted with advanced regression techniques. Single-cell sequencing showed high gene expression in stem cells, immune, and endothelial cells, with validation confirming significant differences between CD patients and controls. These findings suggest circadian rhythm-related genes as promising diagnostic biomarkers for CD.

MYO5B and the Polygenic Landscape of Very Early-Onset Inflammatory Bowel Disease in an Ethnically Diverse Population

BACKGROUND

Genetic discovery in very early-onset inflammatory bowel disease (VEO-IBD) can elucidate not only the origins of VEO-IBD, but also later-onset inflammatory bowel disease. We aimed to investigate the polygenic origins of VEO-IBD in a cohort with a high proportion of Hispanic patients.

METHODS

Patients with VEO-IBD who underwent whole exome sequencing at our center were included. Genes were categorized as genes of interest (GOIs) (129 genes previously described to be associated with VEO-IBD) or non-GOIs. VEO-IBD "susceptibility" single nucleotide variants (SNVs) were identified through enrichment compared with gnomAD (Genome Aggregation Database) and ALFA (Allele Frequency Aggregator) and were scored by Combined Annotation Dependent Depletion for deleteriousness. Gene networks carrying susceptibility SNVs were created. Myosin 5b immunofluorescence was also studied.

RESULTS

Fifty-six patients met inclusion criteria, and 32.1% identified as Hispanic. Monogenic disease was infrequent (8.9%). Significant enrichment of GOI susceptibility SNVs was observed, notably in MYO5B, especially in Hispanics. MEFV, TNFAIP3, SH3TC2, and NCF2 were also central participants in the GOI networks. Myosin 5b immunofluorescence in colonic mucosa was significantly reduced in those with MYO5B susceptibility SNVs compared with control subjects. Seven genes (ESRRA, HLA-DQ1, RETSAT, PABPC1, PARP4, CCDC102A, and SUSD2) were central participants in the non-GOI networks.

CONCLUSIONS

Our results support the polygenic nature of VEO-IBD, in which key participants, like MYO5B, were identified through network analytics. Rare variant load within susceptibility genes may be relevant not only for the genetic origins of inflammatory bowel disease, but also for the age of disease onset. Our findings could guide future work in precision medicine.

Eleven Grand Challenges for Inflammatory Bowel Disease Genetics and Genomics

The past 2 decades have witnessed extraordinary advances in our understanding of the genetic factors influencing inflammatory bowel disease (IBD), providing a foundation for the approaching era of genomic medicine. On behalf of the NIDDK IBD Genetics Consortium, we herein survey 11 grand challenges for the field as it embarks on the next 2 decades of research utilizing integrative genomic and systems biology approaches. These involve elucidation of the genetic architecture of IBD (how it compares across populations, the role of rare variants, and prospects of polygenic risk scores), in-depth cellular and molecular characterization (fine-mapping causal variants, cellular contributions to pathology, molecular pathways, interactions with environmental exposures, and advanced organoid models), and applications in personalized medicine (unmet medical needs, working toward molecular nosology, and precision therapeutics). We review recent advances in each of the 11 areas and pose challenges for the genetics and genomics communities of IBD researchers.

Review on Advances in Pediatric Endoscopy in the Management of Inflammatory Bowel Disease

Over the past decades, an increased importance has been given to gastrointestinal (GI) endoscopy in the management of children with inflammatory bowel diseases (IBD), considering that mucosal healing has been recognized as the optimal endpoint in the treat-to-target paradigm. The recent advances in technology and anesthesia have facilitated the comprehensive evaluation of the GI tract. In this review, we will discuss the role of ileocolonoscopy, upper GI endoscopy, and device-assisted enteroscopy in the work-up and management of pediatric Crohn's disease (CD) and ulcerative colitis, with particular attention on non-invasive endoscopic techniques, such as wireless capsule endoscopy. We will also analyze the most commonly used endoscopic scoring systems, including small bowel scoring systems and endoscopic recurrence grading of neo-terminal ileum CD. Moreover, we will focus on the endoscopic management of complications, such as strictures, that commonly require surgery. Lastly, we will discuss cancer surveillance in children with IBD, with particular consideration of the role of high-definition endoscopic equipment and chromoendoscopy in dysplasia detection rates.

Diabetes and long duration leading to speech-, low/mid-, and high- frequency hearing loss: current evidence from the China National Health Survey 2023

PURPOSE

To examine the effect of diabetes, duration of diabetes, and blood glucose on speech-, low/mid-, and high-frequency hearing loss.

METHODS

In this cross-sectional study, 2821 participants aged 20-87 years in the China National Health Survey were included. Diabetes was defined as valid fasting blood glucose (FBG) of ≥ 7.0 mmol/L, a self-reported history of diabetes or the use of anti-diabetic medications. Speech-(500, 1000, 2000, and 4000 Hz), low/mid- (500, 1000 and 2000 Hz), and high-frequency (4000, 6000, and 8000 Hz) hearing loss was defined as pure tone average of responding frequencies > 20 dB HL in the better ear, respectively.

RESULTS

In fully adjusted models, for speech-, low/mid-, and high-frequency hearing loss, compared with no diabetes, those with diabetes (OR[95%CI]: 1.44 [1.12, 1.86], 1.23 [0.94, 1.61], and 1.75 [1.28, 2.41], respectively) and with diabetes for > 5 years duration (OR[95%CI]: 1.63 [1.09, 2.42], and 1.63 [1.12, 2.36], 2.15 [1.25, 3.70], respectively) were at higher risk. High FBG level was associated with a higher risk of speech-, low/ mid-, and high-frequency hearing loss. And there were stronger associations between HL and diabetes, longer duration and higher in "healthier population" (no hypertension, no dyslipidemia and younger age).

CONCLUSION

Diabetes, longer duration, and higher FBG level were independently associated with hearing loss for speech-, low/mid- and high-frequency hearing loss, particularly in higher frequency and "healthier population". Paying more attention to hearing loss in those populations could lower the burden of hearing loss.

Serological Markers as Predictors of Anti-TNF Response in Children with Crohn's Disease

BACKGROUND

To advance personalized medicine in pediatric Crohn's disease (CD), we aimed to explore the utility of serological biomarkers in predicting response to anti-tumor necrosis factor (TNF).

METHODS

Children with CD were enrolled at initiation of anti-TNF and followed prospectively at 4 and 12 months thereafter, as well as at last follow-up. At baseline, 10 serological markers of the "PROMETHEUS® IBD sgi Diagnostic test" were measured, including pANCA, ASCA IgG and IgA, anti-CBir1, anti-OmpC, anti-A4-Fla2, anti-Fla-X, SAA, ICAM-1 and VCAM-1. The primary outcome was sustained steroid-free remission (SSFR, i.e. clinical remission without steroids at both 4 and 12 months) and the secondary outcome was primary non-response (PNR).

RESULTS

Of the 72 included children (mean age, 12.8 ± 3.1 years; median disease duration, 6.4 months [IQR 2.5-17.3]), 42 (58%) were treated with adalimumab and 30 (42%) with infliximab. PNR was noted in 20 (28%) children and failure to achieve SSFR in 36 (50%). The most common positive serological markers were SAA (86%) and ICAM-1 (82%). In univariate analyses, none of the serological markers achieved statistical significance in association with SSFR or with PNR. In multivariable analysis, positivity of ASCA IgG (OR 3.3 [95%CI 0.8-14.4]) and pANCA (OR 5.3 [95%CI 0.9-48]) were the closest to achieving significance in predicting SSFR, with fair predictive performance for the model (AUC 0.67 [95%CI 0.55-0.80]).

CONCLUSION

The serological markers tested here have limited utility in predicting response to anti-TNF treatment. Further studies with larger sample sizes are needed to confirm the utility of ASCA IgG and pANCA.

Intestinal Goblet Cell-Expressed Reg4 Ameliorates Intestinal Inflammation Potentially by Restraining Pathogenic Escherichia coli Infection

An elevated abundance of Escherichia coli (E. coli) has been linked to the onset and progression of inflammatory bowel disease (IBD). Regenerating islet-derived family member 4 (Reg4) has been isolated from patients with ulcerative colitis (UC), but its functions and involved mechanisms in intestinal inflammation are remain incompletely understood. Therefore, we generated an intestinal conditional Reg4 knockout mouse (Reg4ΔIEC) to address this gap by utilizing murine models of enteropathogenic E. coli (EPEC)-infected bowel and dextran sulfate sodium (DSS)-induced colitis. We here demonstrate that REG4 is increased in diseased intestinal mucosa of pediatric IBD, primarily expressed and enriched in intestinal goblet cells. Deficiency of Reg4 in the intestinal epithelium of mice leads to an increase in the Phylum Proteobacteria and in the family Enterobacteriaceae. Administration of recombinant Reg4 protein significantly mitigates EPEC-induced intestinal inflammation and injury in a murine model. In vitro, Reg4 protein suppresses the growth and motility of EPEC, subsequently reducing their adhesion and invasion to the intestinal epithelial cells. Mechanistically, the conserved mannan-binding sites (like C-lectin domain) are essential for Reg4 antimicrobial activity. Moreover, loss of Reg4 in mice increases susceptibility to DSS-induced colitis, which can be improved by gentamicin (GM), an antibiotic for Gram-negative bacteria. In conclusion, intestinal goblet cell-derived Reg4 is crucial for protection against experimental colitis, likely due to its bactericidal activity against EPEC.

Improvement of Transmural Inflammation With Adalimumab Versus Immunomodulator Maintenance Therapy in Pediatric Crohn's Disease: Single-Center Prospective Evaluation Using the Pediatric Inflammatory Crohn's Magnetic Resonance Enterography Index

BACKGROUND AND AIMS

Transmural healing, including as assessed by magnetic resonance enterography (MRE) has been associated with long-term favorable outcomes in Crohn's Disease (CD), but data concerning MRE improvement and normalization with therapy are sparse. We performed a prospective longitudinal study utilizing the recently developed pediatric MRE-based multi-item measure of inflammation (PICMI) to examine the efficacy of adalimumab (ADA) and immunomodulator (IM) in attaining improvement of transmural inflammation of the small intestine.

METHODS

Pediatric patients with CD involving small bowel and initiating ADA or IM were prospectively enrolled and followed with repeat MRE at 1 year. A single radiologist provided global assessment (RGA) and scored PICMI items (wall thickness, wall diffusion restriction, mural ulcers, comb sign, mesenteric edema) blinded to clinical information and to the timing of MRE. The primary outcome was mild improvement in PICMI at one year without a change in therapy.

RESULTS

Sixty-two eligible patients were enrolled, 26 receiving ADA and 36 IM. On intent to treat basis, a decline in PICMI score of >20 points without change of therapy was observed more frequently in ADA versus IM-treated patients (54% vs 31%, P = .01). By RGA, 71% improved with ADA vs 42% with IM (P = .03). MRE normalization was rare with both treatments (9% vs 6%, P = .62). A change in PICMI of >20 points was confirmed as the best cut off for MRE improvement as assessed by RGA also for the small bowel.

CONCLUSIONS

ADA therapy was associated with objective improvement in MRE findings of inflammation more frequently than IM. The low rate of MRE normalization suggests that this is not yet a realistic target with existing therapies.

Selecting High-Risk Patients With Pediatric Crohn's Disease for Top-Down Anti-TNF as per the 2021 ECCO-ESPGHAN Guidelines: A 5-Year Nationwide Retrospective Analysis From Scotland (2016-2020)

BACKGROUND

The 2021 ECCO-ESPGHAN guideline on the medical management of pediatric Crohn's disease promotes early risk stratification and top-down anti-TNF for patients deemed high risk of severe disease course.

AIMS

We aimed to objectively assess the risk-benefit profile of the guideline's risk stratification policy and guidance on top-down anti-TNF in a nationwide population-based cohort study.

METHODS

Using a prospectively identified nationwide cohort of all new pediatric patients (<17 years) diagnosed with Crohn's disease in Scotland between January 1, 2016 and December 31, 2020 and retrospectively applying the current management algorithm, we explored the guideline's ability to accurately risk stratify patients. Phenotypic and treatment data were retrospectively collected from electronic medical records with a maximum follow-up of 18 months post-diagnosis.

RESULTS

Four hundred and eighteen children (258/418 [62%] male; median [interquartile range {IQR}] age at diagnosis: 13.2 [11.2-14.8] years) were included. High-risk phenotype was present in 224/418 (54%) with 53/224 (24%) of high-risk patients not requiring anti-TNF therapy within 18 months of diagnosis. Conversely, 78/194 (40%) of the low-risk group received anti-TNF within 18 months. High-risk patients were more likely to require anti-TNF (171/224 [76%] vs 78/194 [40%], P < .001) and had shorter median (IQR) time to anti-TNF start (5.0 [1.0-8.0] months vs 6.5 [3.3-13.0] months, P = .01).

CONCLUSIONS

Our data support the guideline's ability to identify patients more likely to require early treatment escalation. However, this approach would have led to potential over- and under-treatment in a substantial proportion of patients. This underscores the importance of frequent and comprehensive monitoring, along with flexible treatment strategies that adapt to changes in disease status.

Provider Specialization in Inflammatory Bowel Diseases: Quality of Care and Outcomes

BACKGROUND & AIMS

Management of inflammatory bowel diseases (IBD) is complex and variation in care has been well-documented. However, the drivers of practice variation remain unexplored. We examined variation based on the treating gastroenterologist's IBD focus (proportion of outpatient visits for IBD).

METHODS

We conducted a retrospective cohort of newly diagnosed patients with IBD using data from Optum's deidentified Clinformatics Data Mart Database (2000-2020). The exposure variable was whether the treating gastroenterologist had an IBD focus (>90th percentile of IBD visits/total outpatient visits). We used adjusted regression models to evaluate associations between provider IBD focus and process measures (use of mesalamine, corticosteroid, biologic, and narcotic medications and endoscopic or radiographic imaging) and clinical outcomes (time to IBD-related hospitalization and bowel resection surgery). We tested for change in treatment patterns over time by including an interaction term for study era (2004-2012 vs 2013-2020).

RESULTS

The study included 772 children treated by 493 providers and 2864 adults treated by 2076 providers. In children, none of the associations between provider focus and process or outcome measures were significant. In adults, care from an IBD-focused provider was associated with more use of biologics, combination therapy, and imaging and endoscopy, and less mesalamine use for Crohn's disease (P < .05 for all comparisons) but not with other process measures. Biologics were prescribed more frequently and narcotics less frequently during the later era (P < .05 for both). Hospitalization and surgery rates were not associated with IBD focus or era.

CONCLUSIONS

IBD care for adults varies by provider specialization. Given the evolving complexity, novel methods may be needed to standardize care.

Crohn's Patients and Healthy Infants Share Immunodominant B Cell Response to Commensal Flagellin Peptide Epitopes

BACKGROUND & AIMS

Inflammatory bowel disease (IBD) is a chronic manifestation of dysregulated immune response to the gut microbiota in genetically predisposed hosts. Nearly half of patients with Crohn's disease (CD) develop selective serum immunoglobulin (Ig)G response to flagellin proteins expressed by bacteria in the Lachnospiraceae family. This study aimed to identify the binding epitopes of these IgG antibodies and assess their relevance in CD and in homeostasis.

METHODS

Sera from an adult CD cohort, a treatment-naïve pediatric CD cohort, and 3 independent non-IBD infant cohorts were analyzed using novel techniques including a flagellin peptide microarray and a flagellin peptide cytometric bead array.

RESULTS

A dominant B cell peptide epitope in patients with CD was identified, located in the highly conserved "hinge region" between the D0 and D1 domains at the amino-terminus of Lachnospiraceae flagellins. Elevated serum IgG reactivity to the hinge peptide was strongly associated with incidence of CD and the development of disease complications in children with CD up to 5 years in advance. Notably, high levels of serum IgG to the hinge epitope were also found in most infants from 3 different geographic regions (Uganda, Sweden, and the United States) at 1 year of age, which decrements rapidly afterward.

CONCLUSIONS

These findings identified a distinct subset of patients with CD, united by a shared reactivity to a dominant commensal bacterial flagellin epitope, that may represent failure of a homeostatic response to the gut microbiota beginning in infancy.

MRI and Blood-based Biomarkers Are Associated With Surgery in Children and Adults With Ileal Crohn's Disease

BACKGROUND

Despite advances in medical therapy, many children and adults with ileal Crohn's disease (CD) progress to fibrostenosis requiring surgery. We aimed to identify MRI and circulating biomarkers associated with the need for surgical management.

METHODS

This prospective, multicenter study included pediatric and adult CD cases undergoing ileal resection and CD controls receiving medical therapy. Noncontrast research MRI examinations measured bowel wall 3-dimensional magnetization transfer ratio normalized to skeletal muscle (normalized 3D MTR), modified Look-Locker inversion recovery (MOLLI) T1 relaxation, intravoxel incoherent motion (IVIM) diffusion-weighted imaging metrics, and the simplified magnetic resonance index of activity (sMaRIA). Circulating biomarkers were measured on the same day as the research MRI and included CD64, extracellular matrix protein 1 (ECM1), and granulocyte-macrophage colony-stimulating factor (GM-CSF) autoantibodies (Ab). Associations between MRI and circulating biomarkers and need for ileal resection were tested using univariate and multivariable LASSO regression.

RESULTS

Our study sample included 50 patients with CD undergoing ileal resection and 83 patients with CD receiving medical therapy; mean participant age was 23.9 ± 13.1 years. Disease duration and treatment exposures did not vary between the groups. Univariate biomarker associations with ileal resection included log GM-CSF Ab (odds ratio [OR], 2.87; P = .0009), normalized 3D MTR (OR, 1.05; P = .002), log MOLLI T1 (OR, 0.01; P = .02), log IVIM perfusion fraction (f; OR, 0.38; P = .04), and IVIM apparent diffusion coefficient (ADC; OR, 0.3; P = .001). The multivariable model for surgery based upon corrected Akaike information criterion included age (OR, 1.03; P = .29), BMI (OR, 0.91; P = .09), log GM-CSF Ab (OR, 3.37; P = .01), normalized 3D MTR (OR, 1.07; P = .007), sMaRIA (OR, 1.14; P = .61), luminal narrowing (OR, 10.19; P = .003), log C-reactive protein (normalized; OR, 2.75; P = .10), and hematocrit (OR, 0.90; P = .13).

CONCLUSION

After accounting for clinical and MRI measures of severity, normalized 3D MTR and GM-CSF Ab are associated with the need for surgery in ileal CD.

Serum Extracellular Matrix Molecules and Their Fragments as Biomarkers of Inflammation and Fibrosis in Inflammatory Bowel Diseases: A Systematic Review

BACKGROUND AND AIM

Contemporary techniques to assess disease activity or bowel damage in patients with inflammatory bowel disease [IBD], such as endoscopy and imaging, are either invasive or lack accuracy. Non-invasive biomarkers for this purpose remain an unmet medical need. Herein, we provide a comprehensive systematic review of studies evaluating blood extracellular matrix [ECM] biomarkers and their relevance in IBD.

METHODS

We conducted a systematic review of PubMed, EMBASE, Web of Science, and Scopus to identify citations pertaining to ECM biomarkers of IBD up to March 1, 2024. Studies were categorized based on marker subtype and clinical use.

RESULTS

Thirty-one ECM markers were identified, 28 of which demonstrated the ability to differentiate IBD disease activity. Collagen III emerged as the most extensively investigated [1212 IBD patients], with the degradation marker C3M and deposition marker PRO-C3 being associated with IBD and subtypes. Collagen V markers C5M and PRO-C5 emerged as the most accurate single markers for diagnosis of IBD, with an area under the curve of 0.91 and 0.93, respectively. Overall, studies were characterized by variable endpoints. None of the studies included histological grading of intestinal damage, repair, or fibrosis formation as the primary outcome in relation to the ECM blood markers.

CONCLUSIONS

Multiple ECM markers are linked with IBD and its phenotypes. However, more rigorous study designs and clearly defined endpoints are needed to ensure reproducibility and develop reliable and accurate biomarkers. ECM markers hold promise as they provide a 'window' into transmural tissue remodelling and fibrosis burden, warranting further investigation.

Clusters of Disease Activity and Early Risk Factors of Clinical Course of Pediatric Crohn's Disease

BACKGROUND

This study aimed to define clusters of disease activity and prognostic factors of disease course in a well-characterized cohort of children with Crohn's disease (CD).

METHODS

All patients from the SIGENP IBD (Italian Society of Pediatric Gastroenterology Hepatology and Nutrition Inflammatory Bowel Disease) registry with a 5-year follow-up and 6-monthly evaluation were included. Active disease was defined for each semester as follows: clinical activity (weighted Pediatric Crohn's Disease Activity Index ≥12.5 or Mucosal Inflammation Noninvasive Index ≥8) and active disease on endoscopy (Simple Endoscopic Score for Crohn's Disease >3 or fecal calprotectin >250 µg/g) or imaging. Formula-based clusters were generated based on previously published patterns in adults.

RESULTS

Data from 332 patients were analyzed. A total of 105 (32%) experienced a quiescent disease course; 49 (15%) and 31 (9%) a moderate-to-severe chronically active and chronic intermittent disease, respectively; 104 (31%) and 43 (13%) had active disease in the first 2 years after diagnosis and remission thereafter and vice versa, respectively. Surgery at diagnosis was significantly associated with a quiescent course (odds ratio [OR], 10.05; 95% confidence interval [CI], 3.05-25.22; P=.0005), while growth impairment at the diagnosis and active disease requiring corticosteroids at 6 months were inversely related to the quiescent group (OR, 0.48; 95% CI, 0.27-0.81; P= .007; and OR, 0.35; 95% CI, 0.16-0.71; P= .005, respectively). Perianal involvement at diagnosis and moderate-severe activity at 6 months correlated with disease progression (OR, 3.85; 95% CI, 1.20-12.85; P=.02).

CONCLUSIONS

During the first 5 years of follow-up, one-third of children with CD experience a quiescent course. However, another one-third have a moderate-to-severe disease course. Surgery at the diagnosis is related to a quiescent course, while growth impairment and lack of response to induction therapy correlate with more severe disease activity during follow-up.

Differences in disease characteristics and treatment exposures between paediatric and adult-onset inflammatory bowel disease using a registry-based cohort

BACKGROUND

Previous studies highlighted a more extensive phenotype for paediatric-onset than adult-onset inflammatory bowel disease (IBD). However, most lacked long-term follow-up, and some were conducted before the era of biologics.

AIMS

The aim of this study is to compare disease characteristics and treatment exposures between paediatric-onset and adult-onset IBD.

METHODS

From a registry that periodically and uniformly retrieves demographics, disease characteristics/phenotype, and treatments, we compared the characteristics of paediatric-onset (diagnosed at ≥6 and <18 years) and adult-onset IBD, diagnosed during 2000-2022 and with ≥12 months follow-up.

RESULTS

Of the 2837 patients with Crohn's disease and 1332 with ulcerative colitis, 3316 had adult-onset and 853 paediatric-onset IBD. The median follow-up was 6 years. Patients with paediatric-onset presented with more extensive disease and received more intensified therapies, including biologics and JAK inhibitors than those with adult-onset IBD. Paediatric-onset ulcerative colitis showed a higher prevalence of E3 extensive colitis including pancolitis and a greater requirement for systemic steroids, immunomodulators, and biologics than adult-onset ulcerative colitis. Paediatric-onset versus adult-onset Crohn's disease exhibited greater L3 ileocolonic involvement and perianal disease phenotype, and higher exposure to immunomodulators and biologics. Kaplan-Meier curve and Cox proportional hazards analyses showed significantly lower 15-year biologic-free survival from diagnosis among those with paediatric-onset IBD than with adult-onset IBD (p = <0.001), indicating greater and earlier use of biologics in the former.

CONCLUSIONS

Paediatric-onset presents with more extensive disease with higher exposures to immunomodulators and biologic therapies than adult-onset IBD.

Single-cell transcriptomics of rectal organoids from individuals with perianal fistulizing Crohn's disease reveals patient-specific signatures

Perianal fistulizing Crohn's disease (CD) is a severe gastrointestinal disorder causing extensive mucosal damage with limited treatment options. Severe manifestations of the disease appear at higher rates in non-Europeans but the genetic and cellular mechanisms driving the disease phenotypes remain poorly understood. Herein, we tested whether pathologic determinants in the epithelial stem cell compartment could be detected at the transcript level in rectal organoids derived from a diverse patient population. Rectal organoid and mucosal cells from endoscopic biopsies of each patient having perianal fistulizing CD or no disease controls were prepared for and sequenced at the single cell level. After cell type annotations based on expressed marker genes, samples were analyzed by principal components, for differential transcript expression, cell type proportions, and pathway enrichment. After QC, we produced 77,044 rectal organoid cells (n = 13 patients; 8 CD, 5 controls) with high quality sequences that identified 10 distinct epithelial subtypes, that we compared to 141,367 mucosal epithelial cells (n = 29 patients; 18 CD, 11 controls). Consistent with mucosal epithelial cells, rectal organoids prominently displayed disease signatures represented by the stem and transit amplifying regions of the rectal crypt, including alterations in transcriptional signatures of metabolic, epigenetic, and proliferating pathways. Organoids also retained their gender- and ancestral-specific gene expression signatures. However, they lacked many of the inflammatory signatures observed in epithelial cells from diseased mucosa. Perianal CD patient derived rectal organoids reflect gene expression signatures related to disease, gender, and ancestry, suggesting they harbor inherent properties amenable to further patient-specific, disease-related experimentation.

The landscape of new therapeutic opportunities for IBD

This chapter presents an overview of the emerging strategies to address the unmet needs in the management of inflammatory bowel diseases (IBD). IBD poses significant challenges, as over half of patients experience disease progression despite interventions, leading to irreversible complications, and a substantial proportion do not respond to existing therapies, such as biologics. To overcome these limitations, we describe a diverse array of novel therapeutic approaches. In the area of immune homeostasis restoration, the focus is on targeting cytokine networks, leukocyte trafficking, novel immune pathways, and cell therapies involving regulatory T cells and mesenchymal stem cells (MSC). Recognizing the critical role of impaired intestinal barrier integrity in IBD, we highlight therapies aimed at restoring barrier function and promoting mucosal healing, such as those targeting cell proliferation, tight junctions, and lipid mediators. Addressing the challenges posed by fibrosis and fistulas, we describe emerging targets for reversing fibrosis like kinase and cytokine inhibitors and nuclear receptor agonists, as well as the potential of MSC for fistulas. The restoration of a healthy gut microbiome, through strategies like fecal microbiota transplantation, rationally defined bacterial consortia, and targeted antimicrobials, is also highlighted. We also describe innovative approaches to gut-targeted drug delivery to enhance efficacy and minimize side effects. Reinforcing these advancements is the critical role of precision medicine, which emphasizes the use of multiomics analysis for the discovery of biomarkers to enable personalized IBD care. Overall, the emerging landscape of therapeutic opportunities for IBD holds great potential to surpass the therapeutic ceiling of current treatments.

Low Anti-Tumor Necrosis Factor Levels During Maintenance Phase Are Associated With Treatment Failure in Children With Crohn's Disease

BACKGROUND

Higher drug levels and combination therapy with low-dose oral methotrexate (LD-MTX) may reduce anti-tumor necrosis factor (TNF) treatment failure in pediatric Crohn's disease. We sought to (1) evaluate whether combination therapy with LD-MTX was associated with higher anti-TNF levels, (2) evaluate associations between anti-TNF levels and subsequent treatment failure, and (3) explore the effect of combination therapy on maintenance of remission among patients with therapeutic drug levels (>5 µg/mL for infliximab and >7.5 µg/mL for adalimumab).

METHODS

We conducted a post hoc analysis of the COMBINE trial, which compared anti-TNF monotherapy to combination therapy with LD-MTX. We included participants who entered maintenance therapy and provided a serum sample approximately 4 months from randomization.

RESULTS

Among 112 infliximab and 41 adalimumab initiators, median drug levels were similar between combination therapy and monotherapy (infliximab: 8.8 vs 7.5 μg/mL [P = .49]; adalimumab: 11.1 vs 10.5 μg/mL [P = .11]). Median drug levels were lower in patients experiencing treatment failure (infliximab: 4.2 vs 9.6 μg/mL [P < .01]; adalimumab: 9.1 vs 12.3 μg/mL [P < .01]). Among patients treated with infliximab with therapeutic drug levels, we observed no difference in treatment failure between participants assigned monotherapy or combination therapy. Among patients treated with adalimumab, a trend towards reduced treatment failure in the combination therapy arm was not statistically significant (P = .14).

CONCLUSIONS

LD-MTX combination was not associated with higher drug levels, but higher drug levels were associated with reduced risk of treatment failure. Among patients with therapeutic drug levels, we observed no benefit of LD-MTX for patients treated with infliximab. A nonsignificant trend towards reduced treatment failure with the addition of LD-MTX patients treated with adalimumab warrants further investigation.

Untargeted faecal metabolomics for the discovery of biomarkers and treatment targets for inflammatory bowel diseases

The gut microbiome has been recognised as a key component in the pathogenesis of inflammatory bowel diseases (IBD), and the wide range of metabolites produced by gut bacteria are an important mechanism by which the human microbiome interacts with host immunity or host metabolism. High-throughput metabolomic profiling and novel computational approaches now allow for comprehensive assessment of thousands of metabolites in diverse biomaterials, including faecal samples. Several groups of metabolites, including short-chain fatty acids, tryptophan metabolites and bile acids, have been associated with IBD. In this Recent Advances article, we describe the contribution of metabolomics research to the field of IBD, with a focus on faecal metabolomics. We discuss the latest findings on the significance of these metabolites for IBD prognosis and therapeutic interventions and offer insights into the future directions of metabolomics research.

Risk factors affecting relapse after discontinuation of biologics in children with Crohn's disease who maintained deep remission

Objectives

Biologics are important therapeutic agents for pediatric Crohn's disease. Discontinuation of biologics is known to increase the relapse rate up to 71.4% in these patients; however, their long-term use increases the risk of opportunistic infections and causes economic burden and psychological fatigue. Therefore, taking a drug holiday is meaningful, even if the biologics cannot be completely discontinued. This study aimed to analyze the risk factors affecting relapse after discontinuation of biologics in children with Crohn's disease.

Methods

We retrospectively reviewed the data of 435 children with Crohn's disease who visited a single health center between March 2013 and March 2021. Subsequently, we analyzed data from the patients who discontinued biologics after deep remission.

Results

Among the enrolled patients, 388 were followed up for ≥2 years, and of these, 357 were administered biologics. A total of 103 patients discontinued biologics after deep remission, subsequently 31 maintained remission and 72 relapsed. The shorter the duration of biologic treatment (odds ratio of 0.444, P = 0.029), the higher the ESR (odds ratio of 1.294, P = 0.009) and fecal calprotectin (odds ratio of 1.010, P = 0.032), and the less histological remission at the time of discontinuation of biologics (odds ratio of 0.119, P = 0.026), the greater the risk of relapse after discontinuation of biologics.

Conclusions

We identified factors associated with relapse after discontinuation of biologics. The results suggest that biologics can be discontinued in the absence of these factors after deep remission. However, because the relapse rate may increase after the discontinuation of biologics, close monitoring is important, and if necessary, re-administration of biologics should be actively considered.

Multiomics reveals microbial metabolites as key actors in intestinal fibrosis in Crohn's disease

Intestinal fibrosis is the primary cause of disability in patients with Crohn's disease (CD), yet effective therapeutic strategies are currently lacking. Here, we report a multiomics analysis of gut microbiota and fecal/blood metabolites of 278 CD patients and 28 healthy controls, identifying characteristic alterations in gut microbiota (e.g., Lachnospiraceae, Ruminococcaceae, Muribaculaceae, Saccharimonadales) and metabolites (e.g., L-aspartic acid, glutamine, ethylmethylacetic acid) in moderate-severe intestinal fibrosis. By integrating multiomics data with magnetic resonance enterography features, putative links between microbial metabolites and intestinal fibrosis-associated morphological alterations were established. These potential associations were mediated by specific combinations of amino acids (e.g., L-aspartic acid), primary bile acids, and glutamine. Finally, we provided causal evidence that L-aspartic acid aggravated intestinal fibrosis both in vitro and in vivo. Overall, we offer a biologically plausible explanation for the hypothesis that gut microbiota and its metabolites promote intestinal fibrosis in CD while also identifying potential targets for therapeutic trials.

Role of ileal diversion in pediatric inflammatory bowel disease

Surgical intervention is often indicated in pediatric inflammatory bowel disease (IBD) for medically refractory disease or complications of severe disease. Specifically, surgical intervention via ileal diversion allows for fecal flow to be redirected away from diseased distal bowel and through an ileostomy. It is utilized in patients who have medically refractory colitis, severe perianal disease, or irreversible bowel damage. In patients with ulcerative colitis, it is primarily performed during a restorative proctocolectomy with ileal pouch anal anastomosis to protect the high-risk anastomoses. In the setting of Crohn's disease, ileal diversion reduces the exposure of diseased distal intestine to pro-inflammatory stool. During perioperative planning, it is crucial for the gastroenterologist to partner early with a multidisciplinary team including surgeons, nutritionists, wound ostomy care nurses, psychologists, and social workers. Patients should be assessed for malnutrition and should be optimized nutritionally with enteral or parenteral nutrition. As they are associated with increased risk of postoperative complications, corticosteroids should be significantly reduced or completely discontinued preoperatively. Though ileal diversion may reduce the complications associated with anastomosis, serious postoperative complications can include diversion colitis and high-output fistulae. This review aims to provide an overview of the role of ileal diversion in the treatment of pediatric IBD to pediatric gastroenterologists to inform their medical decision-making and discussions with patients and families.

Characterization of Biologic Discontinuation Among Pediatric Patients With Crohn's Disease

BACKGROUND & AIMS

Biologic therapies may effectively treat Crohn's disease (CD), and pediatric patients who discontinue multiple biologics risk exhausting treatment options. The frequency and context of biologic discontinuation have not been well-characterized. We aimed to determine patterns of biologic use, discontinuation, and evaluation in pediatric patients with CD.

METHODS

Pediatric patients with CD at 7 U.S. centers (2010-2020) were identified. Prospective ImproveCareNow registry data were supplemented with medical record abstraction. Biologics included monoclonal antibody and small molecule medications. Therapeutic drug monitoring (TDM) was considered induction if <14 weeks after biologic start, proactive if later during quiescent disease, and reactive during active disease.

RESULTS

Of 823 patients included (median age, 13.0 years; 40% female), 86% started biologics (78% infliximab, 21% adalimumab, <1% others). Twenty-six percent used concomitant immunomodulators for ≥12 months. Most (85%) measured TDM including 47% induction, 69% proactive, and 24% reactive. Twenty-nine percent discontinued their first biologic after median 793 days because of inefficacy (34%), anti-drug antibodies (8%), adverse events (8%), or non-adherence (12%). If inefficacy, 86% underwent pre-discontinuation evaluation. If infliximab or adalimumab inefficacy and TDM was done, 62% had levels <10 μg/mL. Proactive TDM and concomitant immunomodulators were associated with 60% and 32% reduced biologic discontinuation.

CONCLUSIONS

Most children with CD are treated with biologics; 25%-37% discontinue biologics, resulting in 1 in 12 using >2 biologics during pediatric care. Half of patients discontinued biologics without trial of high-dose therapy and 14% without any evaluation. Concomitant immunomodulator use and proactive TDM decreased risk of biologic discontinuation. Strategies are needed to preserve biologic efficacy and prevent biologic discontinuation.

Predictors of improvement in disease activity in childhood and adolescent Crohn's disease: an analysis of age, localization, initial severity and drug therapy - data from the Saxon Registry for Inflammatory Bowel Disease in Children in Germany (2000-2014)

The escalating worldwide prevalence of Crohn's disease (CD) among children and adolescents, coupled with a trend toward earlier onset, presents significant challenges for healthcare systems. Moreover, the chronicity of this condition imposes substantial individual burdens. Consequently, the principal objective of CD treatment revolves around rapid inducing remission. This study scrutinizes the impact of age, gender, initial disease localization, and therapy on the duration to achieve disease activity amelioration. Data from the Saxon Pediatric IBD Registry in Germany were analyzed over a period of 15 years. In addition to descriptive methods, logistic and linear regression analyses were conducted to identify correlations. Furthermore, survival analyses and Cox regressions were utilized to identify factors influencing the time to improvement in disease activity. These effects were expressed as Hazard Ratios (HR) with 95% confidence intervals. Data on the clinical course of 338 children and adolescents with CD were available in the registry. The analyses showed a significant correlation between a young age of onset and the severity of disease activity. It was evident that treatment with anti-TNF (Infliximab) was associated with a more favorable prognosis in terms of the time required for improvement in disease activity. Similarly, favorable outcomes were observed with the combination therapies of infliximab with enteral nutrition therapy and Infliximab with immunosuppressants.Conclusion: Our analysis of data from the Saxon Pediatric IBD Registry revealed that the timeframe for improvement of disease activity in pediatric Crohn's disease is influenced by several factors. Specifically, patient age, treatment modality, and initial site of inflammation were found to be significant factors. The study provides important findings that underline the need for individualized treatment.

Nutrient starvation activates ECM remodeling gene enhancers associated with inflammatory bowel disease risk in fibroblasts

Nutrient deprivation induces a reversible cell cycle arrest state termed quiescence, which often accompanies transcriptional silencing and chromatin compaction. Paradoxically, nutrient deprivation is associated with activated fibroblast states in pathological microenvironments in which fibroblasts drive extracellular matrix (ECM) remodeling to alter tissue environments. The relationship between nutrient deprivation and fibroblast activation remains unclear. Here, we report that serum deprivation extensively activates transcription of ECM remodeling genes in cultured fibroblasts, despite the induction of quiescence. Starvation-induced transcriptional activation accompanied large-scale histone acetylation of putative distal enhancers, but not promoters. The starvation-activated putative enhancers were enriched for non-coding genetic risk variants associated with inflammatory bowel disease (IBD), suggesting that the starvation-activated gene regulatory network may contribute to fibroblast activation in IBD. Indeed, the starvation-activated gene PLAU, encoding uPA serine protease for plasminogen and ECM, was upregulated in inflammatory fibroblasts in the intestines of IBD patients. Furthermore, the starvation-activated putative enhancer at PLAU, which harbors an IBD risk variant, gained chromatin accessibility in IBD patient fibroblasts. This study implicates nutrient deprivation in transcriptional activation of ECM remodeling genes in fibroblasts and suggests nutrient deprivation as a potential mechanism for pathological fibroblast activation in IBD.

Epithelial barrier dysfunction and microbial dysbiosis: exploring the pathogenesis and therapeutic strategies for Crohn's disease

Crohn's disease (CD), a chronic gastrointestinal inflammatory disease, is becoming more widespread worldwide. Crohn's disease is caused by gut microbiota changes, genetics, environmental stresses, and immunological responses. Current treatments attempt to achieve long-term remission and avoid complications, delaying disease progression. Immunosuppressive measures and combination medicines should be started early for high-risk patients. These medicines monitor inflammatory indicators and adjust as needed. The epithelial barrier helps defend against physical, chemical, and immunological threats. When tissues' protective barrier breaks down, the microbiome may reach the layer underneath. Unbalanced microbial populations and inflammation impair healing and adjustment. Inflammatory cells infiltrating sensitive tissues aggravate the damage and inflammation. This approach promotes chronic inflammatory diseases. The epithelial barrier hypothesis states that hereditary and environmental variables cause epithelial tissue inflammation. This review focuses on how epithelial barrier break-down and microbial dysbiosis cause Crohn's disease and current advances in understanding the epithelial barrier, immune system, and microbiome. Additionally, investigate treatments that restore barrier integrity and promote microbial balance. Overall, it stresses the role of epithelial barrier failure and microbial dysbiosis in Crohn's disease development and discusses current advances in understanding the barrier, immunological responses, and microbiota.

Autophagy in Disease Onset and Progression

Autophagy is a biological phenomenon whereby components of cells can self-degrade using autophagosomes. During this process, cells can clear dysfunctional organelles or unwanted elements. Autophagy can recycle unnecessary biomolecules into new components or sometimes, even destroy the cells themselves. This cellular process was first observed in 1962 by Keith R. Porter et al. Since then, autophagy has been studied for over 60 years, and much has been learned on the topic. Nevertheless, the process is still not fully understood. It has been proven, for example, that autophagy can be a positive force for maintaining good health by removing older or damaged cells. By contrast, autophagy is also involved in the onset and progression of various conditions caused by pathogenic infections. These diseases generally involve several important organs in the human body, including the liver, kidney, heart, and central nervous system. The regulation of the defects of autophagy defects may potentially be used to treat some diseases. This review comprehensively discusses recent research frontiers and topics of interest regarding autophagy-related diseases.

Nationwide Real-World Exclusive Enteral Nutrition Practice Over Time: Persistence of Use as Induction for Pediatric Crohn's Disease and Emerging Combination Strategy With Biologics

BACKGROUND

Exclusive enteral nutrition (EEN) is the recommended first-line induction treatment in pediatric patients with active luminal Crohn's disease (CD). We aimed to provide a nationwide overview of evolving EEN practices during an era of increasing biologic use.

METHODS

We analyzed a prospectively identified nationwide cohort of newly diagnosed pediatric patients with CD in Scotland between January 1, 2015, and June 30, 2022. Patients who received EEN for any indication were divided into 6-monthly epochs and examined over time. Differences during the COVID-19 pandemic (March 16, 2020, to July 19, 2021) were examined. Data were retrospectively collected from electronic medical records: demographics, anthropometrics, concomitant treatments, aspects of EEN administration, and remission/response rates. Descriptive statistics and linear regression were used for analyses.

RESULTS

A total of 649 patients with CD were identified (63% male; median age 12.6 [interquartile range, 10.8-14.8] years); 497 (77%) of 649 received EEN as postdiagnosis induction therapy with a median course length of 7.7 (interquartile range, 5.9-8.0) weeks. Including repeat courses, 547 EEN courses were examined. An increasing incidence of CD was observed over time with no significant changes in EEN usage, remission or response rates, nasogastric tube usage, or course completion (all P > .05). Increasing use of EEN combined with biologics (combination induction) as first-line induction was observed over time (P < .001). Considering COVID-19, lower rates of EEN usage were observed (P = .008) with no differences in remission, oral administration, and course completion rates (all P > .05).

CONCLUSIONS

Over the past 7.5 years, except during the COVID-19 pandemic, EEN usage rates have not changed despite an increase in biologic use, although combination induction is an emerging trend.

Role of artificial intelligence in Crohn's disease intestinal strictures and fibrosis

Crohn's disease (CD) is a chronic inflammatory disorder of the gastrointestinal tract. Intestinal fibrosis or stricture is one of the most prevalent complications in CD with a high recurrence rate. Manual examination of intestinal fibrosis or stricture by physicians may be biased or inefficient. A rapid development of artificial intelligence (AI) technique in recent years facilitates the detection of existing or possible intestinal fibrosis and stricture in CD through various modalities, including endoscopy, imaging examination, and serological biomarkers. We reviewed the articles on AI application in diagnosing intestinal fibrosis and stricture in CD during the past decade and categorized them into three aspects based on the detection methods, and found that AI helps accurate and expedient identification and prediction of intestinal fibrosis and stenosis in CD.

Mitochondrial function and gastrointestinal diseases

Mitochondria are dynamic organelles that function in cellular energy metabolism, intracellular and extracellular signalling, cellular fate and stress responses. Mitochondria of the intestinal epithelium, the cellular interface between self and enteric microbiota, have emerged as crucial in intestinal health. Mitochondrial dysfunction occurs in gastrointestinal diseases, including inflammatory bowel diseases and colorectal cancer. In this Review, we provide an overview of the current understanding of intestinal epithelial cell mitochondrial metabolism, function and signalling to affect tissue homeostasis, including gut microbiota composition. We also discuss mitochondrial-targeted therapeutics for inflammatory bowel diseases and colorectal cancer and the evolving concept of mitochondrial impairment as a consequence versus initiator of the disease.