Serum immune responses predict rapid disease progression among children with Crohn's disease: immune responses predict disease progression

Noninvasive Stool RNA Test Approximates Disease Activity in Patients With Crohn's Disease

Background and Aims

Management of Crohn's disease (CD) requires frequent monitoring for disease activity and response to therapy. In this study, we examined the clinical utility of a novel stool-derived eukaryotic RNA (seRNA)-based diagnostic in patients with CD.

Methods

Stool samples were collected from 68 individuals for up to 3 time points prior to, and after initiation of an advanced therapy. Stool samples underwent RNA extraction and sequencing using a custom capture panel (n = 1507 transcripts). seRNA signatures were compared to Crohn's Disease Activity Index scores and endoscopies, when available. Random forest models classified disease severity when compared to Crohn's Disease Activity Index scores. seRNA signatures were also used to assess expression of the therapy target and cell type abundance at various time points.

Results

Across all 102 samples collected from 68 individuals, the classifier successfully parsed individuals with active disease (n = 37) relative to those in remission (n = 65) with 87% sensitivity and 77% specificity, respectively. A second classifier, which was employed on subjects with active disease (n = 37), successfully parsed individuals with mild disease (n = 15) from those with moderate disease (n = 22) with 93% and 86% sensitivity, respectively. For the 16 subjects with longitudinal data, seRNA expression of the therapeutic target (eg, ITGA4/ITGB7 for vedolizumab or IL12/IL23 for ustekinumab) as well as lymphocyte burden was correlated with response.

Conclusion

A novel seRNA and informatic-based method reliably discriminates active disease from remission and stratifies mild from moderate CD activity. This demonstrates preliminary feasibility to predict therapeutic response and assess disease activity for patients with CD.

Role of the Gut Microbiome and Bacterial Amyloids in the Development of Synucleinopathies

Less than ten years ago, evidence began to accumulate about association between the changes in the composition of gut microbiota and development of human synucleinopathies, in particular sporadic form of Parkinson's disease. We collected data from more than one hundred and thirty experimental studies that reported similar results and summarized the frequencies of detection of different groups of bacteria in these studies. It is important to note that it is extremely rare that a unidirectional change in the population of one or another group of microorganisms (only an elevation or only a reduction) was detected in the patients with Parkinson's disease. However, we were able to identify several groups of bacteria that were overrepresented in the patients with Parkinson's disease in the analyzed studies. There are various hypotheses about the molecular mechanisms that explain such relationships. Usually, α-synuclein aggregation is associated with the development of inflammatory processes that occur in response to the changes in the microbiome. However, experimental evidence is accumulating on the influence of bacterial proteins, including amyloids (curli), as well as various metabolites, on the α-synuclein aggregation. In the review, we provided up-to-date information about such examples.

Opening avenues for treatment of neurodegenerative disease using post-biotics: Breakthroughs and bottlenecks in clinical translation

Recent studies have indicated the significant involvement of the gut microbiome in both human physiology and pathology. Additionally, therapeutic interventions based on microbiome approaches have been employed to enhance overall health and address various diseases including aging and neurodegenerative disease (ND). Researchers have explored potential links between these areas, investigating the potential pathogenic or therapeutic effects of intestinal microbiota in diseases. This article provides a summary of established interactions between the gut microbiome and ND. Post-biotic is believed to mediate its neuroprotection by elevating the level of dopamine and reducing the level of α-synuclein in substantia nigra, protecting the loss of dopaminergic neurons, reducing the aggregation of NFT, reducing the deposition of amyloid β peptide plagues and ameliorating motor deficits. Moreover, mediates its neuroprotective activity by inhibiting the inflammatory response (decreasing the expression of TNFα, iNOS expression, free radical formation, overexpression of HIF-1α), apoptosis (i.e. active caspase-3, TNF-α, maintains the level of Bax/Bcl-2 ratio) and promoting BDNF secretion. It is also reported to have good antioxidant activity. This review offers an overview of the latest findings from both preclinical and clinical trials concerning the use of post-biotics in ND.

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.

A Novel 8-Predictors Signature to Predict Complicated Disease Course in Pediatric-onset Crohn's Disease: A Population-based Study

BACKGROUND

The identification of patients at high risk of a disabling disease course would be invaluable in guiding initial therapy in Crohn's disease (CD). Our objective was to evaluate a combination of clinical, serological, and genetic factors to predict complicated disease course in pediatric-onset CD.

METHODS

Data for pediatric-onset CD patients, diagnosed before 17 years of age between 1988 and 2004 and followed more than 5 years, were extracted from the population-based EPIMAD registry. The main outcome was defined by the occurrence of complicated behavior (stricturing or penetrating) and/or intestinal resection within the 5 years following diagnosis. Lasso logistic regression models were used to build a predictive model based on clinical data at diagnosis, serological data (ASCA, pANCA, anti-OmpC, anti-Cbir1, anti-Fla2, anti-Flax), and 369 candidate single nucleotide polymorphisms.

RESULTS

In total, 156 children with an inflammatory (B1) disease at diagnosis were included. Among them, 35% (n = 54) progressed to a complicated behavior or an intestinal resection within the 5 years following diagnosis. The best predictive model (PREDICT-EPIMAD) included the location at diagnosis, pANCA, and 6 single nucleotide polymorphisms. This model showed good discrimination and good calibration, with an area under the curve of 0.80 after correction for optimism bias (sensitivity, 79%, specificity, 74%, positive predictive value, 61%, negative predictive value, 87%). Decision curve analysis confirmed the clinical utility of the model.

CONCLUSIONS

A combination of clinical, serotypic, and genotypic variables can predict disease progression in this population-based pediatric-onset CD cohort. Independent validation is needed before it can be used in clinical practice.

The Underappreciated Role of Secretory IgA in IBD

Eighty percent of antibody secreting cells (ASCs) are found in the intestine, where they produce grams of immunoglobulin (Ig) A daily. immunoglobulin A is actively transcytosed into the lumen, where it plays a critical role in modulating the gut microbiota. Although loss of immune tolerance to bacterial antigens is the likely trigger of the dysregulated immune response that characterizes inflammatory bowel disease (IBD), little effort has been placed on understanding the interface between B cells, IgA, and the microbiota during initiation or progression of disease. This may be in part due to the misleading fact that IgA-deficient humans are mostly asymptomatic, likely due to redundant role of secretory (S) IgM. Intestinal B cell recruitment is critically dependent on integrin α4β7-MAdCAM-1 interactions, yet antibodies that target α4β7 (ie, vedolizumab), MAdCAM-1 (ie, ontamalimab), or both β7 integrins (α4β7 and αE [CD103] β7; etrolizumab) are in clinical use or development as IBD therapeutics. The effect of such interventions on the biology of IgA is largely unknown, yet a single dose of vedolizumab lowers SIgA levels in stool and weakens the oral immunization response to cholera vaccine in healthy volunteers. Thus, it is critical to further understand the role of these integrins for the migration of ASC and other cellular subsets during homeostasis and IBD-associated inflammation and the mode of action of drugs that interfere with this traffic. We have recently identified a subset of mature ASC that employs integrin αEβ7 to dock with intestinal epithelial cells, predominantly in the pericryptal region of the terminal ileum. This role for the integrin had not been appreciated previously, nor the αEβ7-dependent mechanism of IgA transcytosis that it supports. Furthermore, we find that B cells more than T cells are critically dependent on α4β7-MAdCAM-1 interactions; thus MAdCAM-1 blockade and integrin-β7 deficiency counterintuitively hasten colitis in interleukin-10-deficient mice. In both cases, de novo recruitment of IgA ASC to the intestinal lamina propria is compromised, leading to bacterial overgrowth, dysbiosis, and lethal colitis. Thus, despite the safe and effective use of anti-integrin antibodies in patients with IBD, much remains to be learned about their various cell targets.

Serological profiling of Crohn’s disease and ulcerative colitis patients reveals anti-microbial antibody signatures

BACKGROUND

The healthcare burden of inflammatory bowel disease (IBD) is rising globally and there are limited non-invasive biomarkers for accurate and early diagnosis.

AIM

To understand the important role that intestinal microbiota play in IBD pathogenesis and identify anti-microbial antibody signatures that benefit clinical management of IBD patients.

METHODS

We performed serological profiling of 100 Crohn’s disease (CD) patients, 100 ulcerative colitis (UC) patients and 100 healthy controls against 1173 bacterial and 397 viral proteins from 50 bacteria and 33 viruses on protein microarrays. The study subjects were randomly divided into discovery (n = 150) and validation (n = 150) sets. Statistical analysis was performed using R packages.

RESULTS

Anti-bacterial antibody responses showed greater differential prevalence among the three subject groups than anti-viral antibody responses. We identified novel antibodies against the antigens of Bacteroidetes vulgatus (BVU_0562) and Streptococcus pneumoniae (SP_1992) showing higher prevalence in CD patients relative to healthy controls. We also identified antibodies against the antigen of Streptococcus pyogenes (SPy_2009) showing higher prevalence in healthy controls relative to UC patients. Using these novel antibodies, we built biomarker panels with area under the curve (AUC) of 0.81, 0.87, and 0.82 distinguishing CD vs control, UC vs control, and CD vs UC, respectively. Subgroup analysis revealed that penetrating CD behavior, colonic CD location, CD patients with a history of surgery, and extensive UC exhibited highest antibody prevalence among all patients. We demonstrated that autoantibodies and anti-microbial antibodies in CD patients had minimal correlation.

CONCLUSION

We have identified antibody signatures for CD and UC using a comprehensive analysis of anti-microbial antibody response in IBD. These antibodies and the source microorganisms of their target antigens improve our understanding of the role of specific microorganisms in IBD pathogenesis and, after future validation, should aid early and accurate diagnosis of IBD.

Biomarkers for the Prediction and Diagnosis of Fibrostenosing Crohn's Disease: A Systematic Review

BACKGROUND AND AIMS

Intestinal strictures are a common complication of Crohn's disease (CD). Biomarkers of intestinal strictures would assist in their prediction, diagnosis, and monitoring. Herein we provide a comprehensive systematic review of studies assessing biomarkers that may predict or diagnose CD-associated strictures.

METHODS

We performed a systematic review of PubMed, EMBASE, ISI Web of Science, Cochrane Library, and Scopus to identify citations pertaining to biomarkers of intestinal fibrosis through July 6, 2020, that used a reference standard of full-thickness histopathology or cross-sectional imaging or endoscopy. Studies were categorized based on the type of biomarker they evaluated (serum, genetic, histopathologic, or fecal).

RESULTS

Thirty-five distinct biomarkers from 3 major groups were identified: serum (20 markers), genetic (9 markers), and histopathology (6 markers). Promising markers include cartilage oligomeric matrix protein, hepatocyte growth factor activator, and lower levels of microRNA-19-3p (area under the curves were 0.805, 0.738, and 0.67, respectively), and multiple anti-flagellin antibodies (A4-Fla2 [odds ratio, 3.41], anti Fla-X [odds ratio, 2.95], and anti-CBir1 [multiple]). Substantial heterogeneity was observed and none of the markers had undergone formal validation. Specific limitations to acceptance of these markers included failure to use a standardized definition of stricturing disease, lack of specificity, and insufficient relevance to the pathogenesis of intestinal strictures or incomplete knowledge regarding their operating properties.

CONCLUSIONS

There is a lack of well-defined studies on biomarkers of intestinal stricture. Development of reliable and accurate biomarkers of stricture is a research priority. Biomarkers can support the clinical management of CD patients and aid in the stratification and monitoring of patients during clinical trials of future antifibrotic drug candidates.

Fungal microbiome in inflammatory bowel disease: a critical assessment

The gut microbiome is at the center of inflammatory bowel disease (IBD) pathogenesis and disease activity. While this has mainly been studied in the context of the bacterial microbiome, recent advances have provided tools for the study of host genetics and metagenomics of host-fungal interaction. Through these tools, strong evidence has emerged linking certain fungal taxa, such as Candida and Malassezia, with cellular and molecular pathways of IBD disease biology. Mouse models and human fecal microbial transplant also suggest that some disease-participatory bacteria and fungi may act not via the host directly, but via their fungal-bacterial ecologic interactions. We hope that these insights, and the study design and multi-omics strategies used to develop them, will facilitate the inclusion of the fungal community in basic and translational IBD research.

Contribution of the Gut Microbiota to Intestinal Fibrosis in Crohn's Disease

In Crohn's disease (CD), intestinal fibrosis is a critical determinant of a patient's prognosis. Although inflammation may be a prerequisite for the initiation of intestinal fibrosis, research shows that the progression or continuation of intestinal fibrosis can occur independently of inflammation. Thus, once initiated, intestinal fibrosis may persist even if medical treatment controls inflammation. Clearly, an understanding of the pathophysiological mechanisms of intestinal fibrosis is required to diminish its occurrence. Accumulating evidence suggests that the gut microbiota contributes to the pathogenesis of intestinal fibrosis. For example, the presence of antibodies against gut microbes can predict which CD patients will have intestinal complications. In addition, microbial ligands can activate intestinal fibroblasts, thereby inducing the production of extracellular matrix. Moreover, in various animal models, bacterial infection can lead to the development of intestinal fibrosis. In this review, we summarize the current knowledge of the link between intestinal fibrosis in CD and the gut microbiota. We highlight basic science and clinical evidence that the gut microbiota can be causative for intestinal fibrosis in CD and provide valuable information about the animal models used to investigate intestinal fibrosis.

Serum exosomal microRNA-144-3p: a promising biomarker for monitoring Crohn's disease

Background

Crohn’s disease (CD) has a tendency for recurrence and requires adequate monitoring and personalized treatment. Since endoscopy is considerably invasive, serum biomarkers are required as alternatives for CD monitoring. Toward this, exosomal microRNAs (miRNAs) may serve as promising candidates. In this study, we aimed to assess the role of serum exosomal microRNA-144-3p (miR-144-3p) as a biomarker for CD monitoring.

Methods

We prospectively recruited 154 patients without a history of surgery (Cohort 1) and 75 patients who were to undergo intestinal resection (Cohort 2). Serum samples were collected from Cohort 1 before colonoscopy and from Cohort 2 before surgery and during post-operative colonoscopic examination. The serum levels of exosomal miR-144-3p were measured using quantitative reverse-transcription polymerase chain reaction (PCR). Correlations between relative exosomal miR-144-3p levels, disease activity, and disease behavior were analysed. The area under the receiver-operating characteristic curve (AUC) was used to assess the predictive value of exosomal miR-144-3p regarding mucosal activity and post-operative recurrence.

Results

A 3.33-fold increase in serum exosomal miR-144-3p levels was recorded in patients with CD compared with those in healthy controls (P < 0.001). The exosomal miR-144-3p levels were positively correlated with the simple endoscopic score of CD (ρ = 0.547, P < 0.001) as well as the Rutgeerts score (ρ = 0.478, P < 0.001). Elevated exosomal miR-144-3p levels were correlated with the penetrating disease with high specificity (100% [95% confidence interval, 95.1%–100%]). The accuracy of exosomal miR-144-3p for identifying post-operative recurrence was higher than that of C-reactive protein (CRP) (AUC, 0.775 vs 0.639; P < 0.001).

Conclusions

Serum exosomal miR-144-3p is a reliable biomarker of mucosal inflammation and penetrating CD. It may identify endoscopic CD recurrence after intestinal resection with higher accuracy than CRP testing.

The Effect of Early vs Delayed Initiation of Adalimumab on Remission Rates in Patients With Crohn's Disease With Poor Prognostic Factors: The MODIFY Study

Background

Data on the effectiveness of anti-tumor necrosis factor medications in patients with Crohn's disease (CD) with poor prognostic factors (PPFs) are scarce. This study aimed to generate real-world evidence on the effect of early (≤24 months after diagnosis) vs delayed (>24 months) initiation of adalimumab (ADL) on the 26-week remission rate (Harvey-Bradshaw Index ≤4) in these patients.

Methods

This multicentre, retrospective, chart review study performed in 10 Greek hospitals enrolled adult patients with moderate to severe CD (Harvey-Bradshaw Index ≥8) with ≥3 PPFs who were initiated on ADL ≥12 months before enrollment. A sample size of 164 patients (early:delayed cohort allocation ratio, 30:70) was required to address the primary endpoint.

Results

Eligible patients (n = 171) were consecutively enrolled. In the early vs delayed cohorts, the 26-week remission rates (off-steroids) using the last-observation-carried-forward imputation method were 60.7% (37/61) vs 47.2% (50/106), respectively (Δ = 13.5%, P = .044). The respective remission rates were 61.2% vs 42.4% among anti-tumor necrosis factor-naive patients (P = .023) and 58.3% vs 53.2% among anti-tumor necrosis factor-experienced patients (P = .374). The 52-week remission rates using as-observed data were 78.8% and 60.3%, and the intestinal resection rates were 6.5% and 11.9% in the early vs delayed ADL cohorts, respectively.

Conclusions

Patients with CD with PPFs who received early vs delayed treatment with ADL achieved higher clinical response and remission rates. This effect was more pronounced in those patients who were bio-naive and steroid-dependent/refractory with concurrent extraintestinal manifestations than those who were not.

Human Microbiota Flagellins Drive Adaptive Immune Responses in Crohn's Disease

BACKGROUND AND AIMS

Crohn's disease and ulcerative colitis are characterized by dysregulated adaptive immune responses to the microbiota in genetically susceptible individuals, but the specificity of these responses remains largely undefined. Therefore, we developed a microbiota antigen microarray to characterize microbial antibody reactivity, particularly to human-derived microbiota flagellins, in inflammatory bowel disease.

METHODS

Sera from healthy volunteers (n = 87) at the University of Alabama at Birmingham and from patients recruited from the Kirklin Clinic of University of Alabama at Birmingham Hospital, including patients with Crohn's disease (n = 152) and ulcerative colitis (n = 170), were individually probed against microbiota bacterial flagellins of both mouse and human origin and analyzed for IgG and IgA antibody responses. Circulating flagellin-reactive T effector (CD4⁺CD154⁺) and T regulatory (CD4⁺CD137⁺) cells were isolated and evaluated in selected patients. Resulting adaptive immune responses were compared with corresponding clinical data to determine relevancy to disease behavior.

RESULTS

We show that patients with IBD express selective patterns of antibody reactivity to microbiota flagellins. Patients with Crohn's disease, but not patients with ulcerative colitis, display augmented serum IgG to human ileal-localized Lachnospiraceae flagellins, with a subset of patients having high responses to more than 10 flagellins. Elevated responses to CBir1, a mouse Lachnospiraceae flagellin used clinically to diagnose CD, correlated with multi-Lachnospiraceae flagellin reactivity. In this subset of patients with CD, multi-flagellin reactivity was associated with elevated flagellin-specific CD154⁺CD45RA^- T memory cells, a reduced ratio of flagellin-reactive CD4⁺ T regulatory to T effector cells, and a high frequency of disease complications.

CONCLUSIONS

Patients with Crohn's disease display strong adaptive immune response to human-derived Lachnospiraceae flagellins, which may be targeted for prognosis and future personalized therapies.

The Relationship Between the Gut Microbiome and Neurodegenerative Diseases

Many recent studies have shown that the gut microbiome plays important roles in human physiology and pathology. Also, microbiome-based therapies have been used to improve health status and treat diseases. In addition, aging and neurodegenerative diseases, including Alzheimer's disease and Parkinson's disease, have become topics of intense interest in biomedical research. Several researchers have explored the links between these topics to study the potential pathogenic or therapeutic effects of intestinal microbiota in disease. But the exact relationship between neurodegenerative diseases and gut microbiota remains unclear. As technology advances, new techniques for studying the microbiome will be developed and refined, and the relationship between diseases and gut microbiota will be revealed. This article summarizes the known interactions between the gut microbiome and neurodegenerative diseases, highlighting assay techniques for the gut microbiome, and we also discuss the potential therapeutic role of microbiome-based therapies in diseases.

Prognostic biomarkers to identify patients likely to develop severe Crohn's disease: a systematic review

BACKGROUND

Identification of biomarkers that predict severe Crohn's disease is an urgent unmet research need, but existing research is piecemeal and haphazard.

OBJECTIVE

To identify biomarkers that are potentially able to predict the development of subsequent severe Crohn's disease.

DESIGN

This was a prognostic systematic review with meta-analysis reserved for those potential predictors with sufficient existing research (defined as five or more primary studies).

DATA SOURCES

PubMed and EMBASE searched from inception to 1 January 2016, updated to 1 January 2018.

REVIEW METHODS

Eligible studies were studies that compared biomarkers in patients who did or did not subsequently develop severe Crohn's disease. We excluded biomarkers that had insufficient research evidence. A clinician and two statisticians independently extracted data relating to predictors, severe disease definitions, event numbers and outcomes, including odds/hazard ratios. We assessed risk of bias. We searched for associations with subsequent severe disease rather than precise estimates of strength. A random-effects meta-analysis was performed separately for odds ratios.

RESULTS

In total, 29,950 abstracts yielded just 71 individual studies, reporting 56 non-overlapping cohorts. Five clinical biomarkers (Montreal behaviour, age, disease duration, disease location and smoking), two serological biomarkers (anti-Saccharomyces cerevisiae antibodies and anti-flagellin antibodies) and one genetic biomarker (nucleotide-binding oligomerisation domain-containing protein 2) displayed statistically significant prognostic potential. Overall, the strongest association with subsequent severe disease was identified for Montreal B2 and B3 categories (odds ratio 4.09 and 6.25, respectively).

LIMITATIONS

Definitions of severe disease varied widely, and some studies confounded diagnosis and prognosis. Risk of bias was rated as 'high' in 92% of studies overall. Some biomarkers that are used regularly in daily practice, for example C-reactive protein, were studied too infrequently for meta-analysis.

CONCLUSIONS

Research for individual biomarkers to predict severe Crohn's disease is scant, heterogeneous and at a high risk of bias. Despite a large amount of potential research, we encountered relatively few biomarkers with data sufficient for meta-analysis, identifying only eight biomarkers with potential predictive capability.

FUTURE WORK

We will use existing data sets to develop and then validate a predictive model based on the potential predictors identified by this systematic review. Contingent on the outcome of that research, a prospective external validation may prove clinically desirable.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42016029363.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 45. See the NIHR Journals Library website for further project information.

Increased Incidence of Inflammatory Bowel Disease After Hirschsprung Disease: A Population-based Cohort Study

OBJECTIVE

To determine the frequency with which inflammatory bowel disease (IBD) is diagnosed in persons with Hirschsprung disease in population-based datasets from 3 Canadian provinces.

STUDY DESIGN

In study I, Ontario data were used to assess the incidence of IBD in a birth cohort of children with Hirschsprung disease relative to children without Hirschsprung disease. In study II, a case-control design was used in Alberta and Manitoba to determine the frequency of previously diagnosed Hirschsprung disease in persons with IBD, compared with the frequency of Hirschsprung disease in matched controls. Validated algorithms for Hirschsprung disease and IBD were applied to each provincial health registry.

RESULTS

In study I, of the 716 children diagnosed with Hirschsprung disease in Ontario since 1991, 18 (2.5%) ultimately developed IBD (168.8 per 100 000 person-years), compared with 7109 of 3 377 394 children without Hirschsprung disease (0.2%, 14.2 per 100 000 person-years). The percentage of males with post-Hirschsprung disease IBD was 77.8%. The incidence rate ratio was 11.9 (95% CI, 7.5-18.8). In study II, the OR of having had Hirschsprung disease before a diagnosis of IBD compared with controls was 74.9 (95% CI, 17.1-328.7) in Alberta and 23.8 (95% CI, 4.6-123) in Manitoba. Crohn's disease was more common after Hirschsprung disease than ulcerative colitis.

CONCLUSIONS

IBD can emerge in more than 2% of patients with Hirschsprung disease and, like Hirschsprung disease itself, is more common in males. IBD is much more common after a diagnosis of Hirschsprung disease than in the general population.

Risk Factors for Disease Behavior Evolution and Efficacy of Biologics in Reducing Progression in Pediatric Patients with Nonstricturing, Nonpenetrating Crohn's Disease at Diagnosis: A Single-Center Experience in Korea

Background/Aims

Recently, the treatment of Crohn’s disease (CD) has changed to a treat-to-target strategy, in which disease progression is prevented with early intervention. We analyzed the long-term evolution of nonstricturing, nonpenetrating (B1) disease at diagnosis and factors related to disease evolution in pediatric CD.

Methods

We retrospectively analyzed 402 patients between 2000 and 2013 who were younger than 18 years and had B1 disease at CD diagnosis. The median follow-up was 6.1 years (range, 1 to 13 years). The cumulative probabilities of developing stricturing (B2) or penetrating (B3) disease and associations between risk factors and disease behavior evolution were evaluated.

Results

Among the 402 patients, 75 (18.7%) had B2 or B3 disease by the final follow-up. The cumulative probabilities of disease behavior evolution were 18.3%, 34.3%, and 50.9% at 5, 10, and 13 years, respectively. Patients whose disease progressed had an increased risk of intestinal resection (hazard ratio [HR], 3.61; 95% confidence interval [CI], 2.25 to 6.03; p<0.001). First-degree family history of inflammatory bowel disease (HR, 2.38; 95% CI, 1.07 to 5.28; p=0.032), isolated ileal involvement at diagnosis (HR, 7.55; 95% CI, 1.04 to 15.57; p=0.045), and positive anti-Saccharomyces cerevisiae antibody titers (HR, 2.10; 95% CI, 1.03 to 4.25; p=0.040) were associated with disease behavior evolution. Early treatment with biologics significantly reduced disease progression (HR, 0.46; 95% CI, 0.79 to 3.39; p=0.042).

Conclusions

This study suggests that early aggressive therapy should be considered in B1 behavior pediatric CD patients with risk factors of disease evolution to improve long-term outcomes.

Fibrotic Strictures in Crohn's Disease: Mechanisms and Predictive Factors

Fibrotic strictures are one of the most severe complications of Crohn's Disease (CD). They occur in about 50% of patients at five years and in 70% at ten years of the diagnosis. The only treatment available for symptomatic fibrotic strictures is surgical resection and endoscopic dilation. Both strategies are associated with a high rate of recurrence, and with multiple surgical resections, which pose the threat of surgical morbidity and short bowel syndrome. Therefore, it is crucial to identify, early, the patients more prone to develop intestinal fibrosis to intensify follow-ups, switch to more aggressive treatments, and suggest lifestyle modifications. Scarce data are available concerning biomarkers and genetic determinants to predict which patient will develop intestinal fibrosis. Biologic or clinical markers would be useful to determine this subgroup of CD patients and to predict the onset of intestinal fibrosis and, ideally, its severity. Furthermore, the identification of environmental risk factors may suggest lifestyle changes aimed at modifying the natural course, thus decreasing the risk of complicated CD. In this review, we will critically revise clinical, environmental, genetic, and serologic factors that have been associated with a complicated CD course with a particular focus on the fibrostenosing phenotype and their possible implications as predictive factors of intestinal fibrosis.

Serological markers facilitate the diagnosis of Crohn's disease

Background and aim: The diagnosis of Crohn's disease (CD) is challenging. Ongoing search for biomarkers to facilitate the diagnosis is a worthwhile endeavor. The aim of this study was to explore the role of serological markers in the diagnosis of CD at an inflammatory bowel disease (IBD) referral center.Methods: This was a retrospective study including 196 suspected CD patients. The expression of ASCA-IgG, ASCA-IgA, AYMA-IgG, AYCA-IgA, FI2Y-IgG, and pANCA in the patient's serum was determined by enzyme-linked immunosorbent assay (ELISA) and indirect immunofluorescence (IF).Results: ASCA was a relatively specific marker for CD (p = 0.0005), but not AYMA-IgG, AYCA-IgA, F12Y-IgG (p = 0.5936, 0.7974, 0.1085, respectively). However, a high sensitivity of 96.77% (95% CI 90.19%-99.83%) was noted for ASCA+/FI2Y+ to identify CD patients among the suspected cases, albeit with low PPV. The more combinations of serological markers, the higher sensitivity, and NPV. No correlation was found between the age of onset or disease location and the expression of ASCA, AYMA, AYCA, FI2Y, or pANCA. There was no significant difference between the expression of ASCA and the disease behavior at diagnosis (p = 0.3307). However, a decreased proportion of AYMA+ CD patients was found in those who received surgery compared with their non-surgical counterparts (p = 0.0488).Conclusions: ASCA was found to be the most accurate serological marker for the differential diagnosis of CD. Combinations of ASCA, AYMA, AYCA, and FI2Y improved diagnostic accuracy of CD.

Predicting Outcomes in Pediatric Crohn's Disease for Management Optimization: Systematic Review and Consensus Statements From the Pediatric Inflammatory Bowel Disease-Ahead Program

BACKGROUND & AIMS

A better understanding of prognostic factors within the heterogeneous spectrum of pediatric Crohn's disease (CD) should improve patient management and reduce complications. We aimed to identify evidence-based predictors of outcomes with the goal of optimizing individual patient management.

METHODS

A survey of 202 experts in pediatric CD identified and prioritized adverse outcomes to be avoided. A systematic review of the literature with meta-analysis, when possible, was performed to identify clinical studies that investigated predictors of these outcomes. Multiple national and international face-to-face meetings were held to draft consensus statements based on the published evidence.

RESULTS

Consensus was reached on 27 statements regarding prognostic factors for surgery, complications, chronically active pediatric CD, and hospitalization. Prognostic factors for surgery included CD diagnosis during adolescence, growth impairment, NOD2/CARD15 polymorphisms, disease behavior, and positive anti-Saccharomyces cerevisiae antibody status. Isolated colonic disease was associated with fewer surgeries. Older age at presentation, small bowel disease, serology (anti-Saccharomyces cerevisiae antibody, antiflagellin, and OmpC), NOD2/CARD15 polymorphisms, perianal disease, and ethnicity were risk factors for penetrating (B3) and/or stenotic disease (B2). Male sex, young age at onset, small bowel disease, more active disease, and diagnostic delay may be associated with growth impairment. Malnutrition and higher disease activity were associated with reduced bone density.

CONCLUSIONS

These evidence-based consensus statements offer insight into predictors of poor outcomes in pediatric CD and are valuable when developing treatment algorithms and planning future studies. Targeted longitudinal studies are needed to further characterize prognostic factors in pediatric CD and to evaluate the impact of treatment algorithms tailored to individual patient risk.

Effect of Crohn's Disease on Villous Length and CYP3A4 Expression in the Pediatric Small Intestine

Changes in absorptive capacity and first‐pass metabolism in the small intestine affect oral drug bioavailability. Characterization of such changes as a consequence of inflammation is important for developing physiologically‐based pharmacokinetic (PBPK) models for inflammatory bowel disease. We sought to elucidate the impact of small intestinal Crohn’s disease (CD) on villous length and CYP3A4 expression in children. Freshly frozen duodenal and terminal ileum (TI) biopsies from 107 children (1–19 years) with and without CD were evaluated for active inflammation. Villous length and CYP3A4 mRNA/protein expression were compared among regions of active and inactive inflammation in CD and controls. A twofold reduction in villous length was observed in inflamed duodena and ilia of children with CD, but in the absence of regional inflammation, villi in CD were comparable in length to controls. Expression of CYP3A4 mRNA correlated significantly with villous length in the TI (P = 0.0003), with a trend observed in the duodenum that did not reach statistical significance. In the presence of active inflammation, a significant decrease in CYP3A protein expression was confirmed in the duodenum, where protein expression also correlated significantly with villous length across diagnoses (P < 0.0001). Our findings suggest that previous observations of decreased CYP3A4 expression and function in inflamed intestine may not be due solely to downregulation by inflammatory cytokines, but also to villous blunting and subsequent loss of surface area for protein expression. This information is relevant for PBPK model development and could aid with dose adjustment decisions for oral CYP3A4 substrates administered during CD flare (e.g., budesonide).

Serum biomarkers of fibrostenotic Crohn's disease: Where are we now?

Intestinal fibrosis and subsequent stricture formation are major clinical challenges in inflammatory bowel disease, resulting in an increased rate of operation and poor prognosis compared with those without. With the changing perception that intestinal fibrosis is irreversible to the point of view that it is reversible in recent years, various candidate serum biomarkers have been studied over the past decades, which may stratify patients based on their risks of developing stenosis and enable the detection of early stages of fibrosis. However, reliable and accurate biomarkers are still unavailable due to conflicting results and the lack of high-quality evidence. In this review we summarized the serum biomarkers that have been proposed for intestinal fibrosis in recent years, which includes gene polymorphisms or variants, epigenetic markers, extracellular matrix components, growth factors, and antibodies, aiming to provide clues for future research.

The Role of Immunomodulators and Biologics in the Medical Management of Stricturing Crohn's Disease

Crohn's disease is a progressive and disabling inflammatory disease involving the gastrointestinal tract. It usually produces inflammatory lesions in the ileocolonic region, but up to half of patients will also develop complications such as strictures in the long term. Indeed, a proportion of patients have progression of the disease with the development of stricturing lesions because there are no drugs that effectively prevent or reverse established fibrosis, and hence these patients are usually treated with surgery or endoscopic balloon dilation. Fibrotic lesions are always associated with some degree of inflammatory changes, but there is little evidence supporting the use of medical therapy in this context. Here, we discuss the most important findings on the possible use of immunomodulators or biologics in the prevention and treatment of intestinal strictures in Crohn's disease patients. Recent evidence demonstrates that these drugs may also be effective in treating lesions with high levels of collagen deposition, and thus might, at least in some patients, reduce the progression of the disease and bowel damage, and further avoid the need for surgery and a disabling course in the long term.

Serological Testing for Mycobacterial Heat Shock Protein Hsp65 Antibody in Health and Diseases

Mycobacterial heat shock protein 65 gene (Hsp65) has been widely used for classification of Mycobacterial species, and detection of Mycobacterial genes by molecular methods and has proven useful in identification of Mycobacterial infection in various clinical conditions. Circulating antibody against Mycobacterial hsp65 has been found in many clinical diseases including autoimmune diseases (Crohn's disease, lupus erythematosus, multiple sclerosis, diabetes, etc.), atherosclerosis and cancers. The prevalence of anti-Hsp65 antibody in the normal healthy population is unknown. We determined the blood levels of antibody against Mycobacterial hsp65 in the normal population represented by 288 blood donors of the American Red Cross and tested the blood of 109 patients with Crohn's disease and 28 patients with Sjogren's syndrome for comparison. The seroprevalence of anti-Hsp65 IgG in the normal population of Red Cross donors was 2.8% (8 of 288 positive). The Hsp65 antibody levels were significantly elevated in patients with Crohn's disease and Sjogren's syndrome. The prevalence of Hsp65 antibody in Crohn's disease patients was 67.9% (74 of 109 patients), and 85.7% for Sjogren's patients (24 of 28 patients). Our data indicate that anti-Hsp65 antibody is rare in the normal population, but frequent in chronic diseases. The presence of circulating Hsp65 antibody reflects an abnormal immune (adaptive) response to Mycobacterial exposure in patients with chronic diseases, thus differentiating the patients with chronic diseases from those clinical mimics.

Variation of Gut Mucosal Microbiome With Anti-Saccharomyces cerevisiae Antibody Status in Pediatric Crohn Disease

OBJECTIVES

Crohn disease (CD) is a chronic relapsing condition possibly caused by a dysbiotic microbiome. Approximately 30% to 60% of patients with CD have anti-Saccharomyces cerevisiae antibody (ASCA), but any association with gut microbiota is unexplored. We hypothesized that ASCA positivity would predict a signature microbial status and clinical phenotype.

METHODS

Ileocolonic mucosal biopsies were obtained from children with CD (n = 135), and controls without inflammatory bowel disease (n = 45). Comparison was made between ASCA status, microbial diversity, and clinical characteristics.

RESULTS

ASCA was highly specific but poorly sensitive for the diagnosis of CD. In patients with CD, ASCA positivity was associated with older age (≥10 years), ileocolonic disease, and long-term risk of surgery. Microbial alpha and beta diversity were similar in patients with CD with or without ASCA, but significantly less when compared to noninflammatory bowel disease controls. Microbial richness was similar across all 3 groups. Fourteen bacterial species were associated with ASCA-positive patients with CD and 14 species with ASCA-negative patients (P < 0.05). After using a false discovery rate correction Ruminococcus torques and bacterium Yersinia enterocolitica 61 remained significantly associated with CD ASCA positivity (P = 0.0178), whereas Enterobacter cloacae and Faecalibacterium prausnitzii were significantly associated with CD ASCA negativity (P = 0.0178 and 0.0342).

CONCLUSION

ASCA-positive and ASCA-negative patients with CD have significant differences in gut microbiome composition, which could possibly be influencing the phenotype of the disease.

Cohort profile of the PRoteomic Evaluation and Discovery in an IBD Cohort of Tri-service Subjects (PREDICTS) study: Rationale, organization, design, and baseline characteristics

Purpose

The etiology of Inflammatory Bowel Disease (IBD) remains currently unknown but evidence would suggest that it results from a complex interplay between genetic susceptibility genes, the intestinal microbiome and the environment, resulting in an increased response towards microbial and self-antigens, followed by the development of pre-clinical intestinal inflammation as a precursor to overt clinical disease. Efforts are needed to provide insights into the characterization of the disease, the possible prediction of complications, and the detection of a pre-clinical disease state where, through early screening and intervention, disease course can be reversed, attenuated or even prevented. A consortium of academic, industry and governmental organization investigators initiated this study to enable an assessment of pre-disease biomarkers in patients newly diagnosed with Crohn's disease (CD) and ulcerative colitis (UC).

Participants

A retrospective cohort of 1000 UC and 1000 CD cases with 500 matched controls was drawn from an active duty US military personnel population with relevant inclusion criteria with three associated pre-disease and a single disease-associated archived serum samples.

Findings to date

The PREDICTS study has been established as a biorepository platform study to perform novel discovery and analysis efforts in the field of IBD and proteomic systems biology.

Future plans

This study is poised to enable the assessment of novel biomarkers within the serum compartment to be analyzed with the goal of identifying pre-disease signals that ultimately predict disease risk, and further elucidate disease pathogenesis in the early stages of the disease process, and identify novel exposures that increase disease risk.

The evidence for fungus in Crohn's disease pathogenesis

Current evidence suggests the etiology of inflammatory bowel diseases (IBD) involves the confluence of host genetic, environmental, and microbial factors that lead to chronic, and often refractory, disease in susceptible individuals. The involvement of microbial triggers in IBD, including Crohn's disease (CD), is increasingly evident with supporting data provided with advancements in metagenomic sequencing that have identified perturbations in microbial structure and function-broadly termed dysbiosis-in CD patients compared with healthy subjects. This concept is supported by the finding germ-free animals with CD genetic susceptibility fail to develop disease; demonstrating microorganisms are necessary but not sufficient for CD. The vast majority of CD microbiome research has focused on the complex bacterial communities and microbiome dysbiosis in the gut with 16S metagenomic sequencing. However, emerging data capturing eukaryotes suggest fungal opportunistic pathogens are also associated with IBD pathogenesis and chronicity. This hypothesis is further supported by historical observations that CD patient populations display elevated antibodies against fungal targets, even evident before disease diagnosis. This review discusses the current findings in the field, followed by historical and metagenomic evidence for fungal pathogens in the development and recurrence of CD in adult and pediatric populations.

Predicting outcomes to optimize disease management in inflammatory bowel disease in Japan: their differences and similarities to Western countries

Inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), is a chronic inflammatory disease of the gastrointestinal tract, with increasing prevalence worldwide. IBD Ahead is an international educational program that aims to explore questions commonly raised by clinicians about various areas of IBD care and to consolidate available published evidence and expert opinion into a consensus for the optimization of IBD management. Given differences in the epidemiology, clinical and genetic characteristics, management, and prognosis of IBD between patients in Japan and the rest of the world, this statement was formulated as the result of literature reviews and discussions among Japanese experts as part of the IBD Ahead program to consolidate statements of factors for disease prognosis in IBD. Evidence levels were assigned to summary statements in the following categories: disease progression in CD and UC; surgery, hospitalization, intestinal failure, and permanent stoma in CD; acute severe UC; colectomy in UC; and colorectal carcinoma and dysplasia in IBD. The goal is that this statement can aid in the optimization of the treatment strategy for Japanese patients with IBD and help identify high-risk patients that require early intervention, to provide a better long-term prognosis in these patients.

Using insurance claims to predict and improve hospitalizations and biologics use in members with inflammatory bowel diseases

OBJECTIVE

Inflammatory Bowel Disease (IBD) is an inflammatory disorder of the gastrointestinal tract that can necessitate hospitalization and the use of expensive biologics. Models predicting these interventions may improve patient quality of life and reduce expenditures.

MATERIALS AND METHODS

We used insurance claims from 2011 to 2013 to predict IBD-related hospitalizations and the initiation of biologics. We derived and optimized our model from a 2011 training set of 7771 members, predicting their outcomes the following year. The best-performing model was then applied to a 2012 validation set of 7450 members to predict their outcomes in 2013.

RESULTS

Our models predicted both IBD-related hospitalizations and the initiation of biologics, with average positive predictive values of 17% and 11%, respectively - each a 200% improvement over chance. Further, when we used topic modeling to identify four member subpopulations, the positive predictive value of predicting hospitalization increased to 20%.

DISCUSSION

We show that our hospitalization model, in concert with a mildly-effective interventional treatment plan for members identified as high-risk, may both improve patient outcomes and reduce insurance expenditures.

CONCLUSION

The success of our approach provides a roadmap for how claims data can complement traditional medical decision making with personalized, data-driven predictive medicine.

Glycosylation of Immunoglobulin G Associates With Clinical Features of Inflammatory Bowel Diseases

BACKGROUND AND AIMS

Causes of inflammatory bowel diseases are not well understood and the most prominent forms, Crohn's disease (CD) and ulcerative colitis (UC), are sometimes hard to distinguish. Glycosylation of IgG has been associated with CD and UC. IgG Fc-glycosylation affects IgG effector functions. We evaluated changes in IgG Fc-glycosylation associated with UC and CD, as well as with disease characteristics in different patient groups.

METHODS

We analyzed 3441 plasma samples obtained from 2 independent cohorts of patients with CD (874 patients from Italy and 391 from the United States) or UC (1056 from Italy and 253 from the US and healthy individuals [controls]; 427 in Italy and 440 from the United States). IgG Fc-glycosylation (tryptic glycopeptides) was analyzed by liquid chromatography coupled to mass spectrometry. We analyzed associations between disease status (UC vs controls, CD vs controls, and UC vs CD) and glycopeptide traits, and associations between clinical characteristics and glycopeptide traits, using a logistic regression model with age and sex included as covariates.

RESULTS

Patients with CD or UC had lower levels of IgG galactosylation than controls. For example, the odds ratio (OR) for IgG1 galactosylation in patients with CD was 0.59 (95% confidence interval [CI], 0.51-0.69) and for patients with UC was 0.81 (95% CI, 0.71-0.92). Fucosylation of IgG was increased in patients with CD vs controls (for IgG1: OR, 1.27; 95% CI, 1.12-1.44), but decreased in patients with UC vs controls (for IgG23: OR, 0.72; 95% CI, 0.63-0.82). Decreased galactosylation associated with more severe CD or UC, including the need for surgery in patients with UC vs controls (for IgG1: OR, 0.69; 95% CI, 0.54-0.89) and in patients with CD vs controls (for IgG23: OR, 0.78; 95% CI, 0.66-0.91).

CONCLUSIONS

In a retrospective analysis of plasma samples from patients with CD or UC, we associated levels of IgG Fc-glycosylation with disease (compared to controls) and its clinical features. These findings could increase our understanding of mechanisms of CD and UC pathogenesis and be used to develop diagnostics or guide treatment.

Serological, genetic and clinical associations with increased health-care resource utilization in inflammatory bowel disease

OBJECTIVE

Inflammatory bowel diseases (IBD) are associated with significant morbidity and economic burden. The variable course of IBD creates a need for predictors of clinical outcomes and health resource utilization (HRU) to guide treatment decisions. We aimed to identify clinical, serological or genetic markers associated with inpatient resource utilization in patients with ulcerative colitis (UC) and Crohn's disease (CD).

METHODS

Patients with IBD with available genetic and serological data who had at least one emergency department visit or hospitalization in a 3-year period were included. The primary outcome measure was HRU, as measured by the All Patient Refined Diagnosis Related Group classification system. Univariate and multivariate linear and logistic regression models were used to identify the associations with HRU.

RESULTS

Altogether 858 (562 CD and 296 UC) patients were included. Anti-CBir1 seropositivity (P = 0.002, effect size [ES]: 0.762, 95% confidence interval [CI] 0.512-1.012) and low socioeconomic status (P = 0.005, ES: 1.620 [95% CI 1.091-2.149]) were independently associated with a high HRU. CD diagnosis (P = 0.006, ES: -0.701 [95% CI -0.959 to -0.443]) was independently associated with a low inpatient HRU.

CONCLUSION

In patients with IBD who required at least one emergency department visit or hospitalization, anti-CBir1 antibody status may be a useful biomarker of HRU when formulating management strategies to reduce disease complications and resource utilization.

The value of serum antibodies in differentiating inflammatory bowel disease, predicting disease activity and disease course in the newly diagnosed patient

BACKGROUND

Data on serum antibodies in untreated adult inflammatory bowel disease (IBD) patients at diagnosis are scarcely available, and results on the stability of antibody presence over time are inconsistent. Our aim was to investigate antibodies in newly diagnosed, untreated IBD patients in relation to disease phenotype and course. Furthermore, we analyzed antibody presence over time.

METHODS

Baseline anti-Saccharomyces cerevisiae antibodies (ASCA), anti-chitobioside carbohydrate antibodies (ACCA), anti-laminaribioside carbohydrate antibodies (ALCA) and anti-mannobioside carbohydrate antibodies (AMCA) were measured with enzyme-linked immunosorbent assays and perinuclear anti-neutrophilic cytoplasmic antibodies (pANCA) was measured by indirect immunofluorescence in serum of 120 untreated IBD patients at diagnosis and 19 healthy controls. Antibodies were related to disease outcomes. Serial measurements were available in 71 patients.

RESULTS

The combination of pANCA and ASCA enabled good discrimination between UC and CD (p = .004). Antibody presence was relatively stable over time, even though there were significant changes in concentrations. There was a trend towards larger fluctuations in concentration with immunosuppressive medication. Baseline pANCA in UC patients correlated with calprotectin values (rho = .545, p = .019) and change in pANCA status over time was associated with disease activity at that moment. No associations were found with antibodies at diagnosis and disease outcomes.

CONCLUSION

Antibody profiles at diagnosis support the distinction between CD and UC. Anti-glycan antibodies are reasonably stable over time, but may fluctuate under the influence of immunosuppressive treatment which may explain the inconsistency in findings hitherto. The appearance or disappearance of pANCA antibodies during follow-up correlated with disease activity in UC and may be used in disease monitoring.

CBirTox is a selective antigen-specific agonist of the Treg-IgA-microbiota homeostatic pathway

Cultivating an environment of mutualism between host cells and the microbiota is vital, and dysregulation of this relationship is associated with multiple immune disorders including metabolic and skin diseases, asthma, allergy, and Inflammatory Bowel Disease (IBD). One prominent mechanism for maintaining homeostasis is the protective regulatory T cell (Treg)- Immunoglobulin A (IgA) pathway toward microbiota antigens, in which Tregs maintain homeostasis and provide critical survival factors to IgA⁺ B cells. In order to amplify the Treg-IgA pathway, we have generated a fusion protein, CBirTox, comprised of a portion of the carboxy terminus of CBir1, a microbiota flagellin, genetically coupled to Cholera Toxin B subunit (CTB) via the A2 linker of CT. Both dendritic cells (DCs) and B cells pulsed with CBirTox selectively induced functional CD4⁺Foxp3⁺ Tregs in vitro, and CBirTox augmented CD4⁺Foxp3⁺ cell numbers in vivo. The induced Foxp3 expression was independent of retinoic acid (RA) signaling but was inhibited by neutralization of TGF-β. CBirTox treatment of B cells downregulated mammalian target of rapamycin (mTOR) signaling. Furthermore, CBirTox-pulsed DCs induced substantial production of IgA from naïve B cells. Collectively these data demonstrate that CBirTox represents a novel approach to bolstering the Treg-IgA pathway at the host-microbiota interface.

(Dis)Trust your gut: the gut microbiome in age-related inflammation, health, and disease

Chronic inflammation represents one of the most consistent biologic features of aging. However, the precise etiology of persistent low-grade increases in inflammation remains unclear. Recent evidence suggests that the gut microbiome may play a key role in age-related inflammation. Indeed, several studies have indicated that older adults display an altered composition of the gut microbiota, and early evidence indicates that this dysbiosis is associated with the presence of several key circulating inflammatory analytes. The present review summarizes knowledge on age-related inflammation and discusses how potential relationships with gut dysbiosis may lead to novel treatment strategies in the future."The pattern of disease is an expression of the response of man to his total environment (physical, biological, and social); this response is, therefore, determined by anything that affects man himself or his environment." - Rene Dubos, 1961.

Serological Epithelial Component Proteins Identify Intestinal Complications in Crohn's Disease

Crohn's Disease (CD) is a relapsing inflammation of the gastrointestinal tract that affects a young working age population and is increasing in developing countries. Half of all sufferers will experience stricturing or fistulizing intestinal complications that require extensive surgical interventions and neither genes nor clinical risk factors can predict this debilitating natural history. We applied discovery and verification phase studies as part of an NCI-FDA modeled biomarker pipeline to identify differences in the low-mass (<25kDa) blood-serum proteome between CD behavioral phenotypes. A significant enrichment of epithelial component proteins was identified in CD patients with intestinal complications using quantitative proteomic profiling with label-free Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS). DAVID 6.7 (NIH) was used for functional annotation analysis of detected proteins and immunoblotting and multiple reaction monitoring (MRM) to verify a priori findings in a secondary independent cohort of complicated CD (CCD), uncomplicated inflammatory CD (ICD), Th1/17 pathway inflammation controls (rheumatoid arthritis), inflammatory bowel disease controls (ulcerative colitis), and healthy controls. Seventy-six high-confidence serum proteins were modulated in CCD versus ICD by LC-MS/MS (p < 0.05, FDR q<0.01), annotating to pathways of epithelial barrier homeostasis (p < 0.01). In verification phase, a putative serology panel developed from discovery proteomics data consisting of desmoglein-1, desmoplakin, and fatty acid-binding protein 5 (FABP5) distinguished CCD from all other groups (p = 0.041) and discriminated complication in CD (70% sensitivity and 72.5% specificity at score ≥1.907, AUC = 0.777, p = 0.007). An MRM assay secondarily confirmed increased FABP5 levels in CCD (p < 0.001). In a longitudinal subanalysis-cohort, FABP5 levels were stable over a two-month period with no behavioral changes (p = 0.099). These studies along the biomarker development pipeline provide substantial proof-of-principle that a blood test can be developed specific to transmural intestinal injury. Data are available via the PRIDE proteomics data repository under identifier PXD001821 and PeptideAtlas with identifier PASS00661.

Eosinophilic colitis in children

INTRODUCTION

Eosinophilic colitis, which is a rare form of eosinophilic gastrointestinal diseases, occurs as primary and secondary allergic eosinophilic colitis of the gastrointestinal tract infection, inflammatory bowel disease, celiac disease, and vasculitis. The diagnosis is based on a significant amount of eosinophils in the inflammatory infiltrate of the colon wall.

AIM

To analyze the clinical picture taking into account comorbidities and endoscopic picture in children with eosinophilic colitis.

MATERIAL AND METHODS

The test group consisted of 43 children, the average age - 12.1 years diagnosed with eosinophilic colitis (according to the Whitington scale) hospitalized in the Gastroenterology Unit, Department of Pediatrics of the Medical University of Silesia in Katowice. Testing for food allergies, celiac disease, inflammatory bowel disease, gastrointestinal diseases and parasitic diseases was performed in the group of children and the analysis concerned the intensity of eosinophilic infiltration of the colon mucosa with the severity of clinical symptoms, endoscopic picture, the presence of inflammatory bowel disease, and food allergy.

RESULTS

Half of the tested children suffered from isolated eosinophilic colitis but the rest of them had eosinophilic infiltrate with inflammatory bowel disease more often, however, the Crohn's disease. The endoscopic image was uncharacteristic, and grade III in the Whitington scale was predominant in the histopathological examination, in most cases located in the entire large intestine. The higher level of total IgE was found in less than half of the patients and it did not correlate with the severity of eosinophilic infiltration. It was shown that the severity of eosinophilic infiltration correlated with exacerbation of clinical symptoms, endoscopic image, and the presence of inflammatory bowel disease. The higher level of antibodies of ASCA and ANCA was found in approximately 20% of the children with isolated eosinophilic colitis and 63% of children with Crohn's disease.

CONCLUSIONS

The higher concentration of total IgE in less than half of the patients with eosinophilic colitis indicates the need for improving allergy diagnosis also in terms of IgE-independent allergy. The presence of higher levels of antibodies of ASCA and ANCA in some of the patients with isolated eosinophilic colitis indicates the need for further observation for the occurrence of inflammatory bowel disease.

Mechanisms, Management, and Treatment of Fibrosis in Patients With Inflammatory Bowel Diseases

In the last 10 years, we have learned much about the pathogenesis, diagnosis, and management of intestinal fibrosis in patients with inflammatory bowel diseases. Just a decade ago, intestinal strictures were considered to be an inevitable consequence of long-term inflammation in patients who did not respond to anti-inflammatory therapies. Inflammatory bowel diseases-associated fibrosis was seen as an irreversible process that frequently led to intestinal obstructions requiring surgical intervention. This paradigm has changed rapidly, due to the antifibrotic approaches that may become available. We review the mechanisms and diagnosis of this serious complication of inflammatory bowel diseases, as well as factors that predict its progression and management strategies.

Serum Cytokine Profiles in Children with Crohn's Disease

Crohn's disease (CD) is a chronic inflammatory bowel disease that can be diagnosed at any age. There are two major patient groups based on diagnosis of this disease, before or after the age of 20 (juvenile/adolescent or adult), with disease progression in adults usually milder than in juvenile CD patients. Immune mechanisms have been suggested to play an important role in CD pathogenesis, with cytokines governing the development of the immune response. Upregulation of inflammatory cytokines in serum of juvenile and adult CD patients has been documented; still little is known about age-dependent differences in serum cytokine profiles of CD patients. We applied multiplex technology to analyze serum levels of 12 cytokines in juveniles and adults. We show that during the acute stage of the disease all CD patients have high serum levels of CXCL10, which remains upregulated during remission. Increased serum levels of TNF-α and IL-6 during the acute stage was characteristic of juvenile CD patients, whereas adult CD patients had upregulated levels of GM-CSF and IFN-γ. Taken together, these results demonstrate age-dependent differences in cytokine profiles, which may affect the pathogenesis of CD in patients at different ages of disease onset.

Predicting Outcomes to Optimize Disease Management in Inflammatory Bowel Diseases

BACKGROUND AND AIMS

Efforts to slow or prevent the progressive course of inflammatory bowel diseases [IBD] include early and intensive monitoring and treatment of patients at higher risk for complications. It is therefore essential to identify high-risk patients - both at diagnosis and throughout disease course.

METHODS

As a part of an IBD Ahead initiative, we conducted a comprehensive literature review to identify predictors of long-term IBD prognosis and generate draft expert summary statements. Statements were refined at national meetings of IBD experts in 32 countries and were finalized at an international meeting in November 2014.

RESULTS

Patients with Crohn's disease presenting at a young age or with extensive anatomical involvement, deep ulcerations, ileal/ileocolonic involvement, perianal and/or severe rectal disease or penetrating/stenosing behaviour should be regarded as high risk for complications. Patients with ulcerative colitis presenting at young age, with extensive colitis and frequent flare-ups needing steroids or hospitalization present increased risk for colectomy or future hospitalization. Smoking status, concurrent primary sclerosing cholangitis and concurrent infections may impact the course of disease. Current genetic and serological markers lack accuracy for clinical use.

CONCLUSIONS

Simple demographic and clinical features can guide the clinician in identifying patients at higher risk for disease complications at diagnosis and throughout disease course. However, many of these risk factors have been identified retrospectively and lack validation. Appropriately powered prospective studies are required to inform algorithms that can truly predict the risk for disease progression in the individual patient.

B Cell-Activating Factor (BAFF)-Targeted B Cell Therapies in Inflammatory Bowel Diseases

Inflammatory bowel diseases (IBD) involve dysregulated immune responses to gut antigens in genetically predisposed individuals. While a better elucidation of IBD pathophysiology has considerably increased the number of treatment options, the need for more effective therapeutic strategies remains a pressing priority. Defects of both non-hematopoietic (epithelial and stromal) and hematopoietic (lymphoid and myeloid) cells have been described in patients with IBD. Within the lymphoid system, alterations of the T cell compartment are viewed as essential in the pathogenesis of IBD. However, growing evidence points to the additional perturbations of the B cell compartment. Indeed, the intestinal lamina propria from IBD patients shows an increased presence of antibody-secreting plasma cells, which correlates with enhanced pro-inflammatory immunoglobulin G production and changes in the quality of non-inflammatory IgA responses. These B cell abnormalities are compounded by the emergence of systemic antibody responses to various autologous and microbial antigens, which predates the clinical diagnosis of IBD and identifies patients with complicated disease. It is presently unclear whether such antibody responses play a pathogenetic role, as B cell depletion with the CD20-targeting monoclonal antibody rituximab did not ameliorate ulcerative colitis in a clinical trial. However, it must be noted that unresponsiveness to rituximab is also observed also in some patients with autoimmune disorders usually responsive to B cell-depleting therapies. In this review, we discussed mechanistic aspects of B cell-based therapies and their potential role in IBD with a special interest on BAFF and BAFF-targeting therapies buoyed by the success of anti-BAFF treatments in rheumatologic disorders.

New Biomarkers for Diagnosing Inflammatory Bowel Disease and Assessing Treatment Outcomes

Despite advances in our understanding of the pathophysiology underlying inflammatory bowel disease, there remains a significant need for biomarkers that can differentiate between Crohn's disease and ulcerative colitis with high sensitivity and specificity, in a cost-efficient manner. As the focus on personalized approaches to the delivery of medical treatment increases, new biomarkers are being developed to predict an individual's response to therapy and their overall disease course. In this review, we will outline many of the existing and recently developed biomarkers, detailing their role in the assessment of patients with inflammatory bowel disease. We will identify opportunities for improvement in our biomarkers, including better differentiation between the subtypes of inflammatory bowel disease. We will also discuss new targets and strategies in biomarker development, including combining modalities to create biomarker signatures to improve the ability to predict disease courses and response to therapy among individual patients.

pANCA and ASCA in Children with IBD-Unclassified, Crohn's Colitis, and Ulcerative Colitis-A Longitudinal Report from the IBD Porto Group of ESPGHAN

INTRODUCTION

No study to date has evaluated perinuclear antineutrophil cytoplasmic antibody (pANCA) and anti-Saccharomyces cerevisiae antibody (ASCA) in pediatric inflammatory bowel disease-unclassified (IBDU) as compared with Crohn's colitis (CC) and ulcerative colitis (UC), which represent the diagnostic challenge. We aimed to explore the diagnostic utility of serology and to assess whether serology can predict disease severity in these subgroups.

METHODS

This was a multicenter retrospective longitudinal study including 406 children with inflammatory bowel diseases (IBD) from 23 centers affiliated with the Porto group of European Society of Pediatric Gastroenterology, Hepatology and Nutrition (mean age 10.5 ± 3.9, 54% males); 117 (29%) with CC, 143 (35%) with UC, and 146 (36%) with IBDU. Median follow-up period was 2.8 years (interquartile range, 1.6-4.2).

RESULTS

The most prevalent serologic profile in IBDU was pANCA-/ASCA- (41%), followed by pANCA+/ASCA- (34%) and pANCA-/ASCA+ (17%). pANCA-/ASCA+ differentiated well between CC versus IBDU (83% specificity, 96% positive predictive value [PPV]) and UC (97% specificity, 90% PPV) patients, albeit with a low negative predictive value (13% and 40%, respectively). pANCA+/ASCA- did not differentiate as well between IBD subgroups, but UC children with pANCA+/ASCA- had more often severe disease at diagnosis (36 [62%] versus 22 [38%], P = 0.033) and needed more often calcineurin inhibitors, biologics, or colectomy (25 [80%] versus 6 [20%], P = 0.026). In CC, double positivity for ASCA and not pANCA-/ASCA+ profile was associated with disease severity.

CONCLUSIONS

Serology may have some role in predicting disease course and outcomes in colonic IBD, but its routine use needs to be supported by more studies. Serology cannot routinely be recommended for differentiating between IBDU versus CC or UC as a sole diagnostic criterion given its low diagnostic utility.

European Crohn's and Colitis Organisation Topical Review on Prediction, Diagnosis and Management of Fibrostenosing Crohn's Disease

This ECCO topical review of the European Crohn's and Colitis Organisation [ECCO] focused on prediction, diagnosis, and management of fibrostenosing Crohn's disease [CD]. The objective was to achieve evidence-supported, expert consensus that provides guidance for clinical practice.

Elevated C-reactive protein is associated with disease progression in patients with mild Crohn's disease

Background

Few studies have been conducted on the progression of mild Crohn’s disease (CD). We aimed to investigate the natural course in mild CD patients with or without bowel damage, to identify predictors of bowel resection and to calculate the requirement for rescue medication.

Methods

A total of 104 patients with mild activity (150 < CDAI < 220) with or without bowel damage were identified from among 1050 CD patients between January 2008 and May 2014. Univariate and multivariate analysis was used to identify factors associated with bowel resection. The cumulative probabilities of bowel resection and rescue medication such as steroids or anti-TNF agents were calculated.

Results

The median follow-up duration was 28.2 months (IQR 26.7). Cumulative probabilities of bowel resection were 0.2, 11.8 and 42.4 % at 1, 3 and 5 years respectively. The CD patients with bowel damage had a higher bowel resection rate than those without bowel damage (P < 0.001). The cumulative probabilities of corticosteroid-requirement were 3.0, 19.6 and 78.4 % of patients at 1, 3 and 5 years, respectively, and 2.1, 11.9 and 56.1 %, in terms of the cumulative probabilities of requiring anti-TNF agents. Patients with elevated CRP (>1.6 mg/dL) were more likely to undergo bowel resection (P = 0.032).

Conclusions

Even in CD patients with mild disease activity, the cumulative probability of bowel resection is not low if they have bowel damage or elevated CRP at baseline. Mild CD patients with bowel damage or elevated CRP at baseline need special attention.