Diagnostics and prognostics of inflammatory bowel disease with fecal neutrophil-derived biomarkers calprotectin and lactoferrin

EVALUATING LACTOFERRIN AND CALPROTECTIN AS MARKERS OF INTESTINAL INFLAMMATION INCHRONIC PANCREATITIS

BACKGROUND

The treatment of chronic pancreatitis does not consistently solve intestinal abnormalities, and despite the implementation of various therapeutic measures, patients often continue to experience persistent diarrhea. Therefore, it is imperative to recognize that diarrhea may stem from factors beyond pancreatic insufficiency, and intestinal inflammation emerges as a potential contributing factor.

OBJECTIVE

The aim of this study was to assess fecal lactoferrin and calprotectin levels as indicators of intestinal inflammation in patients with chronic pancreatitis experiencing persistent diarrhea.

METHODS

In this study, 23 male patients with chronic pancreatitis primarily attributed to alcohol consumption and presenting with diarrhea (classified as Bristol stool scale type 6 or 7), underwent a comprehensive evaluation of their clinical and nutritional status. Fecal lactoferrin and calprotectin levels were mea-sured utilizing immunoassay techniques.

RESULTS

The average age of the participants was 54.8 years, 43.5% had diabetes, and 73.9% were smokers. Despite receiving enzyme replacement therapy and refraining from alcohol for over 4 years, all participants exhibited persistent diarrhea, accompanied by elevated calprotectin and lactoferrin levels indicative of ongoing intestinal inflammation.

CONCLUSION

The findings of this study underscore that intestinal inflammation, as evidenced by elevated fecal biomarkers calprotectin and lactoferrin, may contribute to explaining the persistence of diarrhea in patients with chronic pancreatitis.

BACKGROUND

• Exploration of intestinal inflammation in chronic pancreatitis patients with altered bowel habits.

BACKGROUND

• Assessment of 23 patients using lactoferrin and calprotectin as intestinal inflammation biomarkers.

BACKGROUND

• Intestinal inflammation was detected in all patients; positive correlation between both biomarkers.

BACKGROUND

• Established connection between altered bowel habits and intestinal inflammation in chronic pancreatitis.

The role and mechanism of action of microbiota-derived short-chain fatty acids in neutrophils: From the activation to becoming potential biomarkers

Short-chain fatty acids (SCFAs), such as acetate, propionate, and butyrate, have emerged as critical mediators in the communication between the human microbiota and its host. As the first responder to the inflammatory site, neutrophils play an important role in protecting the host against bacterial infections. Recent investigations revealed that SCFAs generated from microbiota influence various neutrophil activities, including activation, migration, and generation of mediators of inflammatory processes. SCFAs have also been demonstrated to exhibit potential therapeutic benefits in a variety of disorders related to neutrophil dysfunction, including inflammatory bowel disease, viral infectious disorders, and cancer. This study aims to examine the molecular processes behind the complicated link between SCFAs and neutrophils, as well as their influence on neutrophil-driven inflammatory disorders. In addition, we will also provide an in-depth review of current research on the diagnostic and therapeutic value of SCFAs as possible biomarkers for neutrophil-related diseases.

Engineered live bacteria as disease detection and diagnosis tools

Sensitive and minimally invasive medical diagnostics are essential to the early detection of diseases, monitoring their progression and response to treatment. Engineered bacteria as live sensors are being developed as a new class of biosensors for sensitive, robust, noninvasive, and in situ detection of disease onset at low cost. Akin to microrobotic systems, a combination of simple genetic rules, basic logic gates, and complex synthetic bioengineering principles are used to program bacterial vectors as living machines for detecting biomarkers of diseases, some of which cannot be detected with other sensing technologies. Bacterial whole-cell biosensors (BWCBs) can have wide-ranging functions from detection only, to detection and recording, to closed-loop detection-regulated treatment. In this review article, we first summarize the unique benefits of bacteria as living sensors. We then describe the different bacteria-based diagnosis approaches and provide examples of diagnosing various diseases and disorders. We also discuss the use of bacteria as imaging vectors for disease detection and image-guided surgery. We conclude by highlighting current challenges and opportunities for further exploration toward clinical translation of these bacteria-based systems.

Trial in Elderly with Musculoskeletal Problems due to Underlying Sarcopenia-Faeces to Unravel the Gut and Inflammation Translationally (TEMPUS-FUGIT): protocol of a cross-sequential study to explore the gut-muscle axis in the development and treatment of sarcopenia in community-dwelling older adults

BACKGROUND

Gut microbiota (GM) might play a role in muscle metabolism and physiological processes through a hypothesized gut-muscle axis, influencing muscle mass and function and thus, sarcopenia. The Trial in Elderly with Musculoskeletal Problems due to Underlying Sarcopenia-Faeces to Unravel the Gut and Inflammation Translationally (TEMPUS-FUGIT) aims to explore the gut-muscle axis in sarcopenia.

METHODS

First, in a cross-sectional case-control phase, 100 community-dwelling adults without sarcopenia will be compared to 100 community-dwelling adults (≥ 65 years) with sarcopenia of similar age-, gender and BMI-ratio, participating in the ongoing 'Exercise and Nutrition for Healthy AgeiNg' (ENHANce; NCT03649698) study. Sarcopenia is diagnosed according to the European Working Group on Sarcopenia in Older People 2 (EWGSOP2) criteria. GM composition and intestinal inflammatory markers (fecal calprotectin, lactoferrin and S100A12) will be determined in fecal samples. Systemic inflammatory markers (hs-CRP, IL-4, IL-6, TNF-α, IL-13, IL-1β and creatine kinase) will be determined in fasted blood samples. Both groups will be compared using appropriate statistical testing, whereas linear regression will be used for cross-sectional associations between gut, inflammatory and sarcopenia parameters. Second, in the longitudinal phase, sarcopenic older adults will be requested to deliver five fecal samples during the 12-week intervention to assess the effects of protein, omega-3 and a physical exercise program on the GM.

DISCUSSION

TEMPUS-FUGIT aims to explore the gut-muscle axis by comparing GM composition between sarcopenic and non-sarcopenic older adults and to determine the association of GM with intestinal and systemic inflammatory markers and sarcopenia-defining parameters (muscle mass, muscle strength and physical performance). Furthermore, effects of single or combined, optimized and individualized anabolic interventions (exercise, protein and omega-3 supplementation), on GM will be explored in persons with sarcopenia. TEMPUS-FUGIT aims to impact clinical practice by clarifying the relationship between the gut-muscle axis and sarcopenia. TEMPUS-FUGIT is expected to contribute to the discovery of clinical and microbial biomarkers for sarcopenia and insights in its pathophysiology, opening possible future perspectives for novel sarcopenia treatment strategies targeting GM.

TRIAL REGISTRATION

ClinicalTrails.gov NCT05008770, registered on August 17, 2021; first participant enrolled on September 21 2021.

Fecal occult blood and calprotectin testing to prioritize primary care patients for colonoscopy referral: The advantage study

BACKGROUND

Colonoscopy is the gold standard for colorectal cancer (CRC) diagnosis and screening, but endoscopy services are usually overburdened. This study aims to investigate the usefulness of fecal hemoglobin (fHb) and calprotectin (FC) for the identification of patients with high probability of CRC who need urgent referral.

METHODS

In a multicenter prospective study, we enrolled symptomatic patients referred from primary care for colonoscopy. Prior to bowel preparation, fHb and FC quantitative tests were performed. The diagnostic performance was estimated for each biomarker/combination. We built a multivariable predictive model based on logistic regression, translated to a nomogram and a risk calculator to assist clinicians in the decision-making process.

RESULTS

The study included 1224 patients, of whom 69 (5.6%) had CRC. At the fHb cut-offs of >0 and 10 μg/g, the negative predictive values for CRC were 98.8% (95% confidence interval 97.8%-99.3%) and 98.6% (95%CI 97.7%-99.1%), and the sensitivities were 85.5% (95%CI 75.0%-92.8%) and 79.7% (95%CI 68.3%-88.4%), respectively. When we added the cut-off of 150 μg/g of FC to both fHb thresholds, the sensitivity of fecal tests improved. In the multivariate logistic regression model, the concentration of fHb was an independent predictor for CRC; age and gender were also independently associated with CRC.

CONCLUSIONS

fHb and FC are useful as part of a triage tool to identify those symptomatic patients with high probability of CRC. This can be easily applied by physicians to prioritize high-risk patients for urgent colonoscopy.

Morphological Assessment and Biomarkers of Low-Grade, Chronic Intestinal Inflammation in Production Animals

Simple Summary

Production animals are continuously exposed to environmental and dietary factors that might induce a state of low-grade, chronic intestinal inflammation. This condition compromises the productive performance and well-fare of these animals, requiring studies to understand what causes it and to develop control strategies. An intestinal inflammatory process is generally associated with alterations in the structure and functionality of its wall, resulting in the release of cellular components into the blood and/or feces. These components can act as biomarkers, i.e., they are measured to identify and quantify an inflammatory process without requiring invasive methods. In this review we discuss the mechanisms of low-grade inflammation, its effects on animal production and sustainability, and the identification of biomarkers that could provide early diagnosis of this process and support studies of useful interventional strategies.

Abstract

The complex interaction between the intestinal mucosa, the gut microbiota, and the diet balances the host physiological homeostasis and is fundamental for the maximal genetic potential of production animals. However, factors such as chemical and physical characteristics of the diet and/or environmental stressors can continuously affect this balance, potentially inducing a state of chronic low-grade inflammation in the gut, where inflammatory parameters are present and demanding energy, but not in enough intensity to provoke clinical manifestations. It’s vital to expand the understanding of inflammation dynamics and of how they compromise the function activity and microscopic morphology of the intestinal mucosa. These morphometric alterations are associated with the release of structural and functional cellular components into the feces and the blood stream creating measurable biomarkers to track this condition. Moreover, the identification of novel, immunometabolic biomarkers can provide dynamic and predictors of low-grade chronic inflammation, but also provide indicators of successful nutritional or feed additive intervention strategies. The objective of this paper is to review the mechanisms of low-grade inflammation, its effects on animal production and sustainability, and the biomarkers that could provide early diagnosis of this process and support studies of useful interventional strategies.

High Serum Creatine Kinase Levels in Infliximab and Vedolizumab-Treated Inflammatory Bowel Disease Patients

Background

TNF inhibitors are relatively safe drugs, but asymptomatic infliximab-induced high serum creatine kinase (CK) levels have been reported in >30% of patients with inflammatory bowel disease (IBD). Whether high serum CK levels are a specific effect of treatment with TNF inhibitors has not been studied in detail. CK levels were therefore compared between infliximab- and vedolizumab-treated IBD patients.

Methods

In this retrospective, monocentric study, 131 IBD cases (82 with Crohn's disease (CD), 49 with ulcerative colitis) of the Basel University Hospital IBD cohort treated either with infliximab or vedolizumab were included. Serum samples for measuring CK, lactate dehydrogenase (LDH), C-reactive protein (CRP), and fecal calprotectin (FCal) levels were collected longitudinally and analyzed using mixed additive models.

Results

No significant differences in CK levels between infliximab and vedolizumab-treated patients were observed over time. Infliximab-treated males, however, showed significantly higher CK levels than females and former smokers treated with infliximab showed significantly lower CK levels than nonsmokers. No such differences were observed in vedolizumab-treated patients. LDH and CRP were not significantly different between infliximab- and vedolizumab-treated patients, while adjusted groups showed substantially higher LDH levels with increasing age and significantly lower LDH levels in patients with longer disease duration. Infliximab patients with CD showed significantly lower CRP. However, significantly higher FCal concentrations were noted in infliximab patients independent of diagnosis, gender, disease duration, smoking behavior, and age.

Conclusion

In our cohort, high serum CK levels are not an infliximab- or vedolizumab-specific effect.

Mechanisms of Immune Checkpoint Inhibitor-Mediated Colitis

Immune checkpoint inhibitors (ICIs) have provided tremendous clinical benefit in several cancer types. However, systemic activation of the immune system also leads to several immune-related adverse events. Of these, ICI-mediated colitis (IMC) occurs frequently and is the one with the highest absolute fatality. To improve current treatment strategies, it is important to understand the cellular mechanisms that induce this form of colitis. In this review, we discuss important pathways that are altered in IMC in mouse models and in human colon biopsy samples. This reveals a complex interplay between several types of immune cells and the gut microbiome. In addition to a mechanistic understanding, patients at risk should be identifiable before ICI therapy. Here we propose to focus on T-cell subsets that interact with bacteria after inducing epithelial damage. Especially, intestinal resident immune cells are of interest. This may lead to a better understanding of IMC and provides opportunities for prevention and management.

Diagnostic Accuracy of Fecal Calprotectin for the Detection of Small Bowel Crohn's Disease through Capsule Endoscopy: An Updated Meta-Analysis and Systematic Review

Background/Aims

The diagnosis of small bowel Crohn's disease with negative ileocolonoscopic findings has been challenging. Fecal calprotectin (FC) has been used to detect colonic inflammation, but its efficacy for detecting small bowel inflammation is less established. We performed an updated meta-analysis to evaluate the diagnostic accuracy of FC to detect active small bowel inflammation observed during capsule endoscopy.

Methods

We conducted a systematic literature search for studies that evaluated the correlation between small bowel inflammation and FC in patients with suspected/established Crohn's disease. We calculated the pooled sensitivity, specificity, and diagnostic odds ratios (DORs) and constructed hierarchical summary receiver operating characteristic curves for FC cutoffs of 50, 100, and 200 μg/g.

Results

Fourteen studies were eligible for the final analysis. The DORs of all FC cutoffs were significant. The highest DOR was observed at 100 μg/g (sensitivity, 0.73; specificity, 0.73; and DOR, 7.89) and was suggested as the optimal diagnostic cutoff. If we analyzed only studies that included patients with suspected Crohn's disease, the DOR was 8.96. If we analyzed only studies that included patients with a Lewis score ≥135 as a diagnostic criterion for active disease, the DOR was 10.90.

Conclusions

FC has significant diagnostic accuracy for detecting small bowel inflammation, and an FC cutoff of 100 μg/g can be used as a tool to screen for small bowel Crohn's disease.

Milestones of Precision Medicine: An Innovative, Multidisciplinary Overview

Although the concept of precision medicine, in which healthcare is tailored to the molecular and clinical characteristics of each individual, is not new, its implementation in clinical practice has been heterogenous. In some medical specialties, precision medicine has gone from being just a promise to a reality that achieves better patient outcomes. This is a fact if we consider, for example, the great advances made in the genetic diagnosis and subsequent treatment of countless hereditary diseases, such as cystic fibrosis, which have improved the life expectancy of many of the affected children. In the field of oncology, the development of targeted therapies has prolonged the survival of patients with breast, lung, colorectal, melanoma, and hematological malignancies. In other disciplines, clinical milestones are perhaps less well known, but no less important. The current challenge is to expand and generalize the use of technologies that are central to precision medicine, such as massively parallel sequencing, to improve the management (prevention and treatment) of complex conditions such as cardiovascular, kidney, or autoimmune diseases. This process requires investment in specialized expertise, multidisciplinary collaboration, and the nationwide organization of genetic laboratories for diagnosis of specific diseases.

In vivo assessing colitis severity by topical administration of fluorescent probe against neutrophils

Inflammatory bowel disease has become a global burden given its high incidence and refractory to medical treatment. Improved diagnostic strategies to monitor disease activity more accurately are necessary to conduct and evaluate medical treatment. High level of neutrophil infiltration in colon is associated with poor prognosis and enhanced risk of developing colitis-associated cancer. Herein, to accurately monitor neutrophil levels in colitis condition, we designed and constructed a specific probe (CPM), consisting of a neutrophil formyl peptide receptor targeting group (cFLFLFK), a short PEG linker and a near-infrared fluorescent dye. CPM selectively identified neutrophils in vitro and preferentially recognized neutrophils in vivo with enhanced targeting ability and biodistribution property. After verified the ability to target activated neutrophils, CPM was used to detect neutrophils in experimental colitis by systemic and topical administration. Compared to systemic administration, topical administration of CPM allows lower dosage, higher target-to-background ratio and longer duration of effective monitoring. More importantly, we used CPM to assess neutrophil levels in the course of colitis development. The fluorescence intensity of CPM increased along with colitis progression. Additionally, CPM was used to detected neutrophil levels in colitis-associated cancer and enhanced neutrophil infiltration in the tumor sites was detected. In conclusion, the probe CPM is a promising tool for in vivo improved diagnosis of colitis severity by monitoring the extent of neutrophil infiltration.

Faecal cytokine profiling as a marker of intestinal inflammation in acutely decompensated cirrhosis

BACKGROUND & AIMS

Gut dysbiosis and inflammation perpetuate loss of gut barrier integrity (GBI) and pathological bacterial translocation (BT) in cirrhosis, contributing to infection risk. Little is known about gut inflammation in cirrhosis and how this differs in acute decompensation (AD). We developed a novel approach to characterise intestinal immunopathology by quantifying faecal cytokines (FCs) and GBI markers.

METHODS

Faeces and plasma were obtained from patients with stable cirrhosis (SC; n = 16), AD (n = 47), and healthy controls (HCs; n = 31). A panel of 15 cytokines and GBI markers, including intestinal fatty-acid-binding protein-2 (FABP2), d-lactate, and faecal calprotectin (FCAL), were quantified by electrochemiluminescence/ELISA. Correlations between analytes and clinical metadata with univariate and multivariate analyses were performed.

RESULTS

Faecal (F) IL-1β, interferon gamma, tumour necrosis factor alpha, IL-21, IL-17A/F, and IL-22 were significantly elevated in AD vs. SC (q <0.01). F-IL-23 was significantly elevated in AD vs. HC (p = 0.0007). FABP2/d-lactate were significantly increased in faeces in AD vs. SC and AD vs. HC (p <0.0001) and in plasma (p = 0.0004; p = 0.011). F-FABP2 correlated most strongly with disease severity (Spearman's rho: Child-Pugh 0.466; p <0.0001; model for end-stage liver disease 0.488; p <0.0001). FCAL correlated with plasma IL-21, IL-1β, and IL-17F only and none of the faecal analytes. F-cytokines and F-GBI markers were more accurate than plasma in discriminating AD from SC.

CONCLUSIONS

FC profiling represents an innovative approach to investigating the localised intestinal cytokine micro-environment in cirrhosis. These data reveal that AD is associated with a highly inflamed and permeable gut barrier. FC profiles are very different from the classical innate-like features of systemic inflammation. There is non-specific upregulation of TH1/TH17 effector cytokines and those known to mediate intestinal barrier damage. This prevents mucosal healing in AD and further propagates BT and systemic inflammation.

LAY SUMMARY

The gut barrier is crucial in cirrhosis in preventing infection-causing bacteria that normally live in the gut from accessing the liver and other organs via the bloodstream. Herein, we characterised gut inflammation by measuring different markers in stool samples from patients at different stages of cirrhosis and comparing this to healthy people. These markers, when compared with equivalent markers usually measured in blood, were found to be very different in pattern and absolute levels, suggesting that there is significant gut inflammation in cirrhosis related to different immune system pathways to that seen outside of the gut. This provides new insights into gut-specific immune disturbances that predispose to complications of cirrhosis, and emphasises that a better understanding of the gut-liver axis is necessary to develop better targeted therapies.

Lower gastrointestinal symptoms and symptoms-based triaging systems are poor predictors of clinical significant disease on colonoscopy

Introduction

Lower gastrointestinal symptoms (LGS) are a common cause of referral to the gastroenterology service. International guidelines are available to prioritise referrals. Some studies have reported that symptoms alone are a poor marker of clinically significant disease (CSD) but symptoms remain the main way to prioritise referrals in routine clinical practice.

Aims/background

To correlate LGS with colonoscopy findings in an unselected patient cohort and to investigate whether using National Institute for Health and Care Excellence (NICE) guidelines improve risk stratification.

Method

Colonoscopy data over a 2-year period were obtained from our endoscopy database. Only patients with assessment of symptoms as their primary indication for colonoscopy were included. Patient records were retrospectively reviewed. Exclusion criteria: known inflammatory bowel disease (IBD), familial cancer syndromes, polyp and colorectal cancer (CRC) surveillance, and prior colonoscopy within 5 years. Demographics, symptoms and colonoscopy findings were recorded and analysed.

Results

1116 cases were reviewed; 493 (44%) males, age 54.3 years (16–91). CSD occurred in only 162 (14.5%); CRC 19 (1.7%), high-risk adenoma 40 (3.6%), inflammation 97 (8.7%) (IBD 65 (5.8%), microscopic colitis 9 (0.8%) and indeterminate-inflammation 23 (2%)), angiodysplasia 6 (0.5%). Diarrhoea gave the highest diagnostic yield for CSD of 5.3% (OR 3.15, 95% CI 2.2 to 4.7, p<0.001), followed by PR bleeding, 2.9% (OR 1.9, 95% CI 1.24 to 2.9, p=0.003). Weight loss gave the lowest diagnostic yield of 0.4%; (OR 0.79, 95% CI 0.28 to 2.24, p=0.65). 592 (53%) and 517 (46%) fitted the NICE guidelines for CRC and IBD, respectively. Using NICE positivity improved detection but overall yield remained low 3% vs 0.4% (OR 7.71, 95% CI 1.77 to 33.56, p=0.0064) for CRC, and 9% vs 2.8% (OR 3.5, 95% CI 1.99 to 6.17, p<0.0001) for IBD.

Conclusions

The overall prevalence of CSD in our unselected symptomatic patients is low (14.5%). A holistic approach including combining symptoms and demographics with novel tools including stool biomarkers and minimally invasive colonoscopy alternatives should be applied to avoid unnecessary colonoscopy.

Biomarkers Predictive of Response to Thiopurine Therapy in Inflammatory Bowel Disease

The complex nature of inflammatory bowel disease (IBD) often results in treatment failure for many patients. With some patients cycling through multiple therapies before achieving a sustained period of remission, the ability to predict a patient's response to therapeutics could decrease the time from active disease to clinical remission and mucosal healing. The prospect of such individualized treatment of IBD would be aided by accurate biomarkers, both fecal and serological, which have to date shown value as indicators of IBD activity. Here we review the utility of generic biomarkers for inflammation or mucosal healing, such as calprotectin, C-reactive protein (CRP), and fecal hemoglobin (fHb) as predictors of response to treatment of IBD. We further provide a deeper insight into the utility of monitoring the thiopurine treatment by thiopurine metabolites or alternative hematologic parameters. In light of multiple recent publications of biomarkers and biological therapy, our focus in this review is predicting response to thiopurine treatment only, that is, Azathioprine and 6-Mercaptopurine.

Comparison of different histological indexes in the assessment of UC activity and their accuracy regarding endoscopic outcomes and faecal calprotectin levels

OBJECTIVE

Histological remission is being increasingly acknowledged as a therapeutic endpoint in patients with UC. The work hereafter described aimed to evaluate the concordance between three histological classification systems-Geboes Score (GS), Nancy Index (NI) and RobartsHistopathologyIndex (RHI), as well as to evaluate their association with the endoscopic outcomes and the faecal calprotectin (FC) levels.

DESIGN

Biopsy samples from 377 patients with UC were blindly evaluated using GS, NI and RHI. The results were compared with the patients' Mayo Endoscopic Score and FC levels.

RESULT

GS, NI and RHI have a good concordance concerning the distinction between patients in histological remission or activity. RHI was particularly close to NI, with 100% of all patients classified as being in remission with NI being identified as such with RHI and 100% of all patients classified as having activity with RHI being identified as such with NI. These scores could also predict the Mayo Endoscopic Score and the FC levels, with their sensitivity and specificity levels depending on the chosen cut-offs. Moreover, higher FC levels were statistically associated with the presence of neutrophils in the epithelium, as well as with ulceration or erosion of the intestinal mucosa.

CONCLUSIONS

GS, NI and RHI histopathological scoring systems are comparable in what concerns patients' stratification into histological remission/activity. Additionally, FC levels are increased when neutrophils are present in the epithelium and the intestinal mucosa has erosions or ulcers. The presence of neutrophils in the epithelium is, indeed, the main marker of histological activity.

Swimming attenuates inflammation, oxidative stress, and apoptosis in a rat model of dextran sulfate sodium-induced chronic colitis

Increasing evidence suggests that regular physical exercise suppresses chronic inflammation. However, the potential inhibitory effects of swimming on dextran sulfate sodium (DSS)-induced chronic colitis, and its underlying mechanisms, remain unclear. In this study, rats were orally administered DSS to induce chronic colitis, and subsequently treated with or without swimming exercise. A 7-week swimming program (1 or 1.5 hours per day, 5 days per week) ameliorated DSS-caused colon shortening, colon barrier disruption, spleen enlargement, serum LDH release, and reduction of body weight gain. Swimming for 1.5 hours per day afforded greater protection than 1 hour per day. Swimming ameliorated DSS-induced decrease in crypt depth, and increases in myeloperoxidase activity, infiltration of Ly6G⁺ neutrophils and TNF-a- and IFN-?-expressing CD3⁺ T cells, as well as fecal calprotectin and lactoferrin. Swimming inhibited pro-inflammatory cytokine and chemokine production and decreased the protein expression of phosphorylated nuclear factor-?B p65 and cyclooxygenase 2, whereas it elevated interleukin-10 levels. Swimming impeded the generation of reactive oxygen species, malondialdehyde, and nitric oxide; however, it boosted glutathione levels, total antioxidant capacity, and superoxide dismutase and glutathione peroxidase activities. Additionally, swimming decreased caspase-3 activity and expression of apoptosis-inducing factor, cytochrome c, Bax, and cleaved-caspase-3, but increased Bcl-2 levels. Overall, these results suggest that swimming exerts beneficial effects on DSS-induced chronic colitis by modulating inflammation, oxidative stress, and apoptosis.

MUB40 Binds to Lactoferrin and Stands as a Specific Neutrophil Marker

Neutrophils represent the most abundant immune cells recruited to inflamed tissues. A lack of dedicated tools has hampered their detection and study. We show that a synthesized peptide, MUB₄₀, binds to lactoferrin, the most abundant protein stored in neutrophil-specific and tertiary granules. Lactoferrin is specifically produced by neutrophils among other leukocytes, making MUB₄₀ a specific neutrophil marker. Naive mammalian neutrophils (human, guinea pig, mouse, rabbit) were labeled by fluorescent MUB₄₀ conjugates (-Cy5, Dylight405). A peptidase-resistant retro-inverso MUB₄₀ (RI-MUB₄₀) was synthesized and its lactoferrin-binding property validated. Neutrophil lactoferrin secretion during in vitro Shigella infection was assessed with RI-MUB₄₀-Cy5 using live cell microscopy. Systemically administered RI-MUB₄₀-Cy5 accumulated at sites of inflammation in a mouse arthritis inflammation model in vivo and showed usefulness as a potential tool for inflammation detection using non-invasive imaging. Improving neutrophil detection with the universal and specific MUB₄₀ marker will aid the study of broad ranges of inflammatory diseases.

Increased fecal calprotectin levels in Crohn's disease correlate with elevated serum Th1- and Th17-associated cytokines

Background

Patient-reported symptoms and endoscopic disease activity do not correlate well in Crohn’s disease (CD). This warrants the need for reliable biomarkers to early detect active intestinal inflammation. Currently, the fecal calprotectin level is the most commonly used biomarker for inflammatory activity in CD. However, the diagnostic accuracy of the fecal calprotectin level is not fully efficacious and diagnosis may be further improved by the identification of other biomarkers for active CD. Here, we studied the association of a variety of serum disease markers with fecal calprotectin levels in CD patients.

Methods

39 CD patients were included and subdivided into ‘normal’ (defined as < 200 mg/kg feces) and ‘increased’ (defined as > 200 mg/kg feces) fecal calprotectin level groups. Serum levels of 37 different cytokines, chemokines and markers for angiogenesis and vascular injury were quantified by an electrochemiluminescence multiplex assay (V-PLEX Human Biomarker 40-Plex Kit of Meso Scale Discovery ^®). Correlations between individual biomarkers and the fecal calprotectin level were assessed using Spearman’s correlation coefficient (ρ).

Results

A highly significant positive correlation was observed between the pro-inflammatory serum cytokines IFN-γ and CRP and fecal calprotectin levels (P < 0.01). Moreover, fecal calprotectin levels showed a significant positive correlation with IL-6, TNF-β, SAA and IL-17A (P < 0.05).

Conclusion

We show that a positive correlation exists between multiple serum Th1- and Th17-associated cytokines and the fecal calprotectin level. These cytokines and CRP may serve as additional biomarkers for determining disease activity and evaluating treatment response in CD. Ultimately, this may result in more efficient treatment of active disease in CD patients and prevention of complications.

Bacterial translocation markers in liver cirrhosis

Bacterial translocation (BT) is an important mechanism in the development of infection in liver cirrhosis. The migration and colonization of bacteria and/or bacterial products from the bowel to mesenteric lymph nodes is a controlled process in healthy persons. Increased intestinal permeability, bacterial overgrowth and defect of gut-associated lymphatic tissue promote impaired BT in cirrhotics. We reviewed the reports on markers used for the evaluation of BT published between 1987 and 2016. We focused on the clinical consequences of BT in cirrhosis, as indicated by the values of the BT markers. Patients with cirrhosis are reported to have elevated levels of surrogate markers associated with BT compared with controls. The most widely used BT parameters are C-reactive protein, procalcitonin, bacterial DNA, endotoxin or lipopolysaccharide, lipopolysaccharide binding protein, calprotectin, and bactericidal/permeability increasing protein. High levels of these factors in serum and/or ascitic fluid in humans may be associated with advanced liver disease, hemodynamic instability, high levels of proinflammatory cytokines, susceptibility to the development of severe or recurrent infections, acute-on-chronic liver failure, hepatic encephalopathy, hepatorenal syndrome and poor prognosis during follow up. In conclusion, high levels of BT markers are associated with a high inflammatory response, increased complications of liver cirrhosis and occasionally high fatality rates.

An orally administered butyrate-releasing derivative reduces neutrophil recruitment and inflammation in dextran sulphate sodium-induced murine colitis

BACKGROUND AND PURPOSE

Butyrate has shown benefits in inflammatory bowel diseases. However, it is not often administered orally because of its rancid smell and unpleasant taste. The efficacy of a more palatable butyrate-releasing derivative, N-(1-carbamoyl-2-phenylethyl) butyramide (FBA), was evaluated in a mouse model of colitis induced by dextran sodium sulphate (DSS).

EXPERIMENTAL APPROACH

Male 10 week-old BALB/c mice received DSS (2.5%) in drinking water (for 5 days) followed by DSS-free water for 7 days (DSS group). Oral FBA administration (42.5 mg·kg-1 ) was started 7 days before DSS as preventive (P-FBA), or 2 days after DSS as therapeutic (T-FBA); both treatments lasted 19 days. One DSS-untreated group received only tap water (CON).

KEY RESULTS

FBA treatments reduced colitis symptoms and colon damage. P-FBA and T-FBA significantly decreased polymorphonuclear cell infiltration score compared with the DSS group. FBA reversed the imbalance between pro- and anti-inflammatory cytokines (reducing inducible NOS protein expression, CCL2 and IL-6 transcripts in colon and increasing TGFβ and IL-10). Morever, P-FBA and T-FBA limited neutrophil recruitment (by expression and localization of the neutrophil granule protease Ly-6G), restored deficiency of the butyrate transporter and improved intestinal epithelial integrity, preventing tight-junction impairment (zonulin-1 and occludin). FBA, similar to its parental compound sodium butyrate, inhibited histone deacetylase-9 and restored H3 histone acetylation, exerting an anti-inflammatory effect through NF-κB inhibition and the up-regulation of PPARγ.

CONCLUSIONS AND IMPLICATIONS

FBA reduces inflammatory intestinal damage in mice indicating its potential as a postbiotic derivative without the problems associated with the oral administration of sodium butyrate.

LINKED ARTICLES

This article is part of a themed section on Principles of Pharmacological Research of Nutraceuticals. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.11/issuetoc.

Immunomodulatory Yersinia outer proteins (Yops)-useful tools for bacteria and humans alike

Human-pathogenic Yersinia produce plasmid-encoded Yersinia outer proteins (Yops), which are necessary to down-regulate anti-bacterial responses that constrict bacterial survival in the host. These Yops are effectively translocated directly from the bacterial into the target cell cytosol by the type III secretion system (T3SS). Cell-penetrating peptides (CPPs) in contrast are characterized by their ability to autonomously cross cell membranes and to transport cargo - independent of additional translocation systems. The recent discovery of bacterial cell-penetrating effector proteins (CPEs) - with the prototype being the T3SS effector protein YopM - established a new class of autonomously translocating immunomodulatory proteins. CPEs represent a vast source of potential self-delivering, anti-inflammatory therapeutics. In this review, we give an update on the characteristic features of the plasmid-encoded Yops and, based on recent findings, propose the further development of these proteins for potential therapeutic applications as natural or artificial cell-penetrating forms of Yops might be of value as bacteria-derived biologics.

Normative Fecal Calprotectin Concentrations in Guatemalan Preschoolers Are High Relative to Children Reported Elsewhere

BACKGROUND

Calprotectin is a fecal marker of intraintestinal inflammation derived from activated enteric neutrophils and macrophages. It is useful as a clinical marker in inflammatory bowel diseases; furthermore, it may have a role in public health epidemiology.

OBJECTIVES

The aim of the study was to describe the distribution of fecal calprotectin in Guatemalan preschool children sharing a common institutional diet; to relate it collectively to pediatric distributions in other geographic settings, and individually to concomitant indicators of intestinal infection or colonization and other descriptive features of the child.

METHODS

Fecal samples were collected in 87 subjects, ages 2 to 7 years across 3 daycare centers sharing a common institutional menu, but from different ecological settings. Stools were examined, variously by routine light microscopy, quantitative egg counts, and a Giardia antigen test, for microbiological diagnosis, and an ELISA assay for fecal calprotectin (CalproLab).

RESULTS

The median fecal calprotectin value was 58 mg/kg, with a mean of 98 ± 136 mg/kg and a range from 10 to 950 mg/kg; 61% of values were above the manufacturer's cut-off for elevated concentration and 51% exceeded an age-adjusted criterion. There were no associations between sex, age, growth indicators, or fecal microbiological findings by microscopy or ELISA assays, alone or in combination. The central tendency (mean or median) and distribution were generally shifted to the right in relation to comparable reports from children across the world literature.

CONCLUSIONS

Although specific, low-grade intestinal infections do not define calprotectin subgroups, right-shifted fecal calprotectin status in this population may reflect a general and diffuse stress of adverse environmental sanitation.

Short article: The effect of implementation of a treatment algorithm for infliximab on remission rates and drug costs in inflammatory bowel disease patients

INTRODUCTION

The effective, but expensive, drug infliximab is used in patients with inflammatory bowel disease (IBD). Monitoring infliximab trough levels and anti-infliximab antibody (ATI) formation can lead to a more cost-effective use of infliximab therapy. The aim of our study was to investigate the effect of implementation of a treatment algorithm for infliximab in a single-centre IBD cohort, focussing on remission rates and drug costs.

METHODS

IBD patients aged 18 years or older treated with infliximab were asked to participate in this study. Remission rates were assessed using faecal calprotectin levels and a validated questionnaire. Infliximab trough levels and ATIs were determined at baseline and at the third infliximab infusion. According to the advice given by the treatment algorithm, infliximab dosage adjustments were performed at the second infliximab infusion.

RESULTS

Between January and December 2015 a total of 62 IBD patients in our centre were treated with infliximab, of whom 33 (53%) patients agreed to participate in this study. The number of patients in remission was 28 (85%) at baseline and there were 13 dose adaptations suggested by the treatment algorithm for the successive second infusion. Four patients possessed undetectable infliximab levels and positive ATI status at baseline. After the second infusion, there were 29 (88%) patients in remission at the third infusion. All of this resulted in an annual drug cost reduction of &OV0556;47 026 (7.4%).

CONCLUSION

Our developed treatment algorithm of infliximab led to optimization of infliximab therapy in IBD patients by increasing remission rates and reducing drug costs.

Similar Depletion of Protective Faecalibacterium prausnitzii in Psoriasis and Inflammatory Bowel Disease, but not in Hidradenitis Suppurativa

BACKGROUND AND AIMS

Psoriasis and hidradenitis suppurativa [HS] co-occur more often with inflammatory bowel disease [IBD] than expected, due to shared pathogenic and genetic features. It is known that IBD patients harbour an altered intestinal microbiome characterised by a depletion of Faecalibacterium prausnitzii and increase of Escherichia coli. At present, it is unclear whether a similar intestinal microbiome trend can be identified in IBD-associated skin disorders. We therefore investigated the F. prausnitzii and E. coli abundance in psoriasis and HS, with and without concomitant IBD.

METHODS

Using quantitative polymerase chain reaction , we compared the F. prausnitzii and E. coli abundances in faecal samples from healthy controls [n = 33] with samples from patients with psoriasis [n = 29], IBD [n = 31], and concomitant IBD and psoriasis [n = 13]. Likewise, we analysed samples from patients with HS [n = 17], and concomitant IBD and HS [n = 17].

RESULTS

Psoriasis patients harboured a significantly lower abundance of F. prausnitzii in their stool than healthy controls [p < 0.001], which was similar to IBD patients. Together with the reduced F. prausnitzii levels, the psoriasis patients had a significantly higher abundance of E. coli [p < 0.001]. No significant difference in F. prausnitzii or E. coli abundance was found in HS. It was apparent that patients with concomitant IBD and associated skin disorder had the greatest decrease of F. prausnitzii and increase of E. coli.

CONCLUSIONS

The study demonstrates, for the first time, an IBD-like decrease of F. prausnitzii together with an increase of E.coli in psoriasis, supporting the presence of a gut-microbiome-skin axis in psoriasis and IBD.

Correlation Between Calprotectin and Modified Rutgeerts Score

BACKGROUND

Endoscopic recurrence after surgery for Crohn's disease (CD) is high, and it has important prognostic value. Crohn's disease will recur in the majority of patients after surgery. Fecal calprotectin (FC) and lactoferrin (FL) have attracted interest in the postoperative setting for predicting relapse. We have evaluated the accuracy of FC and FL in diagnosing endoscopic recurrence (ER) using the modified Rutgeerts score (MRS) compared with the Rutgeerts score (RS).

METHODS

A series of consecutive patients who underwent ileocolonic resection for Crohn's disease were evaluated. Biomarkers, clinical indexes, and fecal markers were recorded on the day of ileocolonoscopy. ER was defined as a MRS ≥ i2b or a RS ≥ i2.

RESULTS

Ninety-nine patients were included in this prospective cohort. The median time between surgery and colonoscopy was 87.5 months (IQR, 31-137). FC and FL levels were higher in patients with ER than in those in remission (Median FC, 196.5 μg/g [IQR, 96-634 μg/g] versus 42.1 μg/g [IQR 19-91.60 μg/g; P < 0.001]; Median FL, 23.27 μg/g [IQR 8.9-47.8 μg/g] versus 2 μg/g [IQR 0.9-7.26 μg/g; P < 0.001]). Using the MRS, 34% of patients presented with ER compared with 76% if the RS was used. The RS performed worse than the MRS with a decrease in sensitivity (74% versus 48% for FC and 85% versus 55% for FL) and in NPV (91% versus 33% for FC, and 90% versus 37% for FL). Furthermore, the accuracy of the MRS was higher than that of the RS (75% versus 55%).

CONCLUSIONS

Both FC and FL proved to correlate well with endoscopic findings in the evaluation of Crohn's disease after surgery. Both markers predicted recurrence with greater accuracy when the MRS was used. Fecal markers can be used to monitor disease recurrence after intestinal resection, with patients being selected to undergo further endoscopic evaluation.

Faecal haemoglobin and faecal calprotectin as indicators of bowel disease in patients presenting to primary care with bowel symptoms

OBJECTIVE

In primary care, assessing which patients with bowel symptoms harbour significant disease (cancer, higher-risk adenoma or IBD) is difficult. We studied the diagnostic accuracies of faecal haemoglobin (FHb) and faecal calprotectin (FC) in a cohort of symptomatic patients.

DESIGN

From October 2013 to March 2014, general practitioners were prompted to request FHb and FC when referring patients with bowel symptoms to secondary care. Faecal samples were analysed for haemoglobin (EIKEN OC-Sensor io) and calprotectin (BÜHLMANN Calprotectin ELISA). Patients triaged to endoscopy were investigated within 6 weeks. All clinicians and endoscopists were blind to the faecal test results. The diagnostic accuracies of FHb and FC for identification of significant bowel disease were assessed.

RESULTS

1043 patients returned samples. FHb was detectable in 57.6% (median 0.4 µg/g, 95% CI 0.4 to 0.8; range 0-200). FC at 50 µg/g or above was present in 60.0%. 755 patients (54.6% women, median age 64 years (range 16-90, IQR 52-73)) returned samples and completed colonic investigations. 103 patients had significant bowel disease; the negative predictive values of FHb for colorectal cancer, higher-risk adenoma and IBD were 100%, 97.8% and 98.4%, respectively. Using cut-offs of detectable FHb and/or 200 µg/g FC detected two further cases of IBD, one higher-risk adenoma and no additional cancers.

CONCLUSIONS

In primary care, undetectable FHb is a good 'rule-out' test for significant bowel disease and could guide who requires investigation.

Concentrations of neutrophil-derived proteins in meconium and their correlations

AIM

The aim was to measure concentrations of four neutrophil-derived proteins in meconium as biomarkers describing prenatal environment.

METHODS

Calprotectin, lactoferrin, myeloperoxidase and PMN-elastase concentrations were measured using ELISA kits in serial meconium portions (n = 81) from 20 healthy neonates.

RESULTS

The highest concentration was for calprotectin (286.5 ± 214.6 µg/g) with a positive correlation (r = 0.75, p < 0.0001) with myeloperoxidase (1.81 ± 1.72 µg/g). For PMN-elastase (1.70 ± 2.69 µg/g) a negative correlation was observed with calprotectin and myeloperoxidase (r = -0.51, p < 0.0001; r = -0.60, p < 0.0001, respectively). Concentration of lactoferrin (45.07 ± 78.53 µg/g) correlated only with that of myeloperoxidese (r = 0.36, p = 0.0009).

CONCLUSION

Calprotectin, lactoferrin, myeloperoxidase and PMN-elastase concentrations in meconium are interrelated. These proteins may serve as objective biomarkers describing and/or assessing the intrauterine environment.

Association Between Fecal Calprotectin Levels and Small-bowel Inflammation Score in Capsule Endoscopy: A Multicenter Retrospective Study

BACKGROUND

Accurate inflammation reporting in capsule endoscopy (CE) is important for diagnosis and monitoring of treatment of inflammatory bowel disease (IBD). Fecal calprotectin (FC) is a highly specific biomarker of gut inflammation. Lewis score (LS) was developed to standardize quantification of inflammation in small-bowel (SB) CE images.

GOALS

Multicenter retrospective study aiming to investigate correlation between LS and FC in a large group of patients undergoing CE for suspected or known small-bowel IBD, and to develop a model for prediction of CE results (LS) based on FC levels.

STUDY

Five academic centers and a district general hospital offering CE in UK, Finland, Sweden, Canada, and Israel. In total, 333 patients were recruited. They had small-bowel CE and FC done within 3 months.

RESULTS

Overall, correlation between FC and LS was weak (r s: 0.232, P < 0.001). When two clinically significant FC thresholds (100 and 250 μg/g) were examined, the r s between FC and LS was 0.247 (weak) and 0.337 (moderate), respectively (P = 0.307). For clinically significant (LS ≥ 135) or negative (LS < 135) for SB inflammation, ROC curves gave an optimum cutoff point of FC 76 μg/g with sensitivity 0.59 and specificity 0.41.

LIMITATIONS

Retrospective design.

CONCLUSIONS

LS appears to show low correlation with FC as well as other serology markers of inflammation. FC does not appear to be a reliable biomarker for significant small-bowel inflammation. Nevertheless, FC level ≥ 76 μg/g may be associated with appreciable visual inflammation on small-bowel CE in patients with negative prior diagnostic workup.

Fecal Calprotectin: Diagnostic Accuracy of the Immunochromatographic CalFast Assay in a Pediatric Population

BACKGROUND

Fecal calprotectin is a noninvasive marker for bowel diseases and it is high valuable to follow disease activity in Crohn's disease (CD) and ulcerative colitis (UC). In this study, we evaluated the diagnostic performance of the recently introduced immunochromatographic assay CalFast in comparison to the well-known ELISA tests for calprotectin assay to obtain a rapid diagnosis of bowel inflammation in pediatric patients.

METHODS

CalFast was tested in parallel to the classic ELISA tests CalPrest and PhiCal (gold standards for the calprotectin determination) on 148 fecal samples from pediatric subjects including 104 healthy subjects, 29 with CD, and 15 with UC.

RESULTS

In this study, the sensitivity and specificity of CalFast, CalPrest, and PhiCal were 86.4%, 88.6%, and 93.2% and 86.6%, 74%, and 64.4%, respectively. The area under the curve, obtained from receiver operating characteristic analysis, indicated the lack of significant difference among all the kits used.

CONCLUSION

The immunochromatographic assay demonstrated good diagnostic predictive values, comparable to those of the ELISA methods, and may represent a valid alternative in order to save operators' time. The test, in fact, has a short turnaround time and does not need a specific ELISA instrumentation.

Clinical application of faecal calprotectin in ulcerative colitis patients

OBJECTIVE

Faecal calprotectin (FC) is the most relevant noninvasive biomarker for monitoring inflammatory status, response to treatment and for predicting clinical relapse in ulcerative colitis (UC). The aim of this study was to evaluate the role of FC in predicting both clinical/endoscopic activity and clinical relapse in a large UC patient cohort.

PATIENTS AND METHODS

A two-phase prospective study was carried out. In the first phase, the relationship between FC and clinical/endoscopic activity was evaluated. In the second phase, a cohort of asymptomatic patients with endoscopic mucosal healing was followed up using clinical and FC level determinations.

RESULTS

One hundred and twenty-one UC patients were enrolled. The FC concentrations were directly correlated with both clinical and endoscopic activity (r=0.76 and 0.87, respectively, P<0.05) and were capable of differentiating between different degrees of endoscopic severity (P<0.01). An FC cut-off value of 110 μg/g was highly predictive (95%) of endoscopic activity. Seventy-four patients in clinical remission with mucosal healing were followed up for a year or until relapse and 27% developed a clinical relapse. The FC concentration of nonrelapsed patients (48 μg/g) versus relapsed patients (218 μg/g) was significantly different (P<0.01). An FC cut-off value of 193 μg/g had an accuracy of 89% in predicting clinical relapse. High FC levels were associated with clinical relapse using survival analysis and multivariate analysis.

CONCLUSION

Our data strongly support the use of FC for staging the activity of disease, predicting relapse and leading decision-making in a UC setting.

Disease monitoring in inflammatory bowel disease

The optimal method for monitoring quiescent disease in patients with Crohn’s disease (CD) and ulcerative colitis is yet to be determined. Endoscopic evaluation with ileocolonoscopy is the gold standard but is invasive, costly, and time-consuming. There are many commercially available biomarkers that may be used in clinical practice to evaluate disease status in patients with inflammatory bowel disease (IBD), but the most widely adopted biomarkers are C-reactive protein (CRP) and fecal calprotectin (FC). This review summarizes the evidence for utilizing CRP and FC for monitoring IBD during clinical remission and after surgical resection. Endoscopic correlation with CRP and FC is evaluated in each disease state. Advantages and drawbacks of each biomarker are discussed with special consideration of isolated ileal CD. Fecal immunochemical testing, traditionally used for colorectal cancer screening, is mentioned as a potential new alternative assay in the evaluation of IBD. Based on a mixture of information gleaned from biomarkers, clinical status, and endoscopic evaluation, the best treatment decisions can be made for the patient with IBD.

The diagnostic usefulness of fecal lactoferrin in the assessment of Crohn's disease activity

BACKGROUND

Diagnosis and monitoring of Crohn's disease (CD) is difficult and time-consuming. In recent years, diagnostic usefulness of fecal calprotectin has been proven. However, data on the utility of other fecal markers are scarce.

AIMS

To evaluate the usefulness of fecal lactoferrin (FL) in the assessment of CD activity.

METHODS

The group consisted of 101 CD patients (median age: 30 years, IQR: 24-37). FL was measured in a single stool sample by using the immunoenzymatic methods. The clinical activity of the disease was evaluated by using the Crohn's Disease Activity Index (CDAI). Depending on the location of the disease, either a colonoscopy or magnetic resonance enterography was performed or both in order to evaluate the disease activity by using appropriate endoscopic and enterographic scores.

RESULTS

Median FL concentration was 84.14 (IQR: 36.4-302.9) μg/ml and it correlated with C-reactive protein concentration (p=0.0000001, r=0.5), CDAI (p=0.002, r=0.3) and colonic Simple Endoscopic Score for Crohn's Disease (SES-CD) (p=0.000004, r=0.5). Assuming endoscopic remission in the large intestine with colonic SES-CD≤3 points, a ROC curve showed that FL concentration of 145.82 μg/ml had 84.6% sensitivity and 60.5% specificity in discriminating CD patients with endoscopically active and inactive disease [AUC: 0.676 (95% CI: 0.531-0.8), (p=0.0347)]. The positive predictive value for this concentration was 42% and negative predictive value -92%.

CONCLUSIONS

FL is a sensitive marker of CD activity and it reliably reflects the mucosal inflammatory lesions in large intestine. Thus, it can be helpful in diagnostics and monitoring of CD.

Markers of bacterial translocation in end-stage liver disease

Bacterial translocation (BT) refers to the passage of viable bacteria or bacterial products from the intestinal lumen, through the intestinal epithelium, into the systemic circulation and extraintestinal locations. The three principal mechanisms that are thought to be involved in BT include bacterial overgrowth, disruption of the gut mucosal barrier and an impaired host defence. BT is commonly observed in liver cirrhosis and has been shown to play an important role in the pathogenesis of the complications of end stage liver disease, including infections as well as hepatic encephalopathy and hepatorenal syndrome. Due to the importance of BT in the natural history of cirrhosis, there is intense interest for the discovery of biomarkers of BT. To date, several such candidates have been proposed, which include bacterial DNA, soluble CD14, lipopolysaccharides endotoxin, lipopolysaccharide-binding protein, calprotectin and procalcitonin. Studies on the association of these markers with BT have demonstrated not only promising data but, oftentimes, contradictory results. As a consequence, currently, there is no optimal marker that may be used in clinical practice as a surrogate for the presence of BT.

Fecal Microbiota in Pediatric Inflammatory Bowel Disease and Its Relation to Inflammation

OBJECTIVES

Inflammatory bowel disease (IBD) is considered to result from interplay between host and intestinal microbiota. While IBD in adults has shown to be associated with marked changes in the intestinal microbiota, there are only a few studies in children, and particularly studies focusing on therapeutic responses are lacking. Hence, this prospective study addressed the intestinal microbiota in pediatric IBD especially related to the level of inflammation.

METHODS

In total, 68 pediatric patients with IBD and 26 controls provided stool and blood samples in a tertiary care hospital and 32 received anti-tumor necrosis factor-α (anti-TNF-α). Blood inflammatory markers and fecal calprotectin levels were determined. The intestinal microbiota was characterized by phylogenetic microarray and qPCR analysis.

RESULTS

The microbiota varied along a gradient of increasing intestinal inflammation (indicated by calprotectin levels), which was associated with reduced microbial richness, abundance of butyrate producers, and relative abundance of Gram-positive bacteria (especially Clostridium clusters IV and XIVa). A significant association between microbiota composition and inflammation was indicated by a set of bacterial groups predicting the calprotectin levels (area under curve (AUC) of 0.85). During the induction of anti-TNF-α, the microbial diversity and similarity to the microbiota of controls increased in the responder group by week 6, but not in the non-responders (P<0.01; response related to calprotectin levels). The abundance of six groups of bacteria including those related to Eubacterium rectale and Bifidobacterium spp. predicted the response to anti-TNF-α medication.

CONCLUSIONS

Intestinal microbiota represents a potential biomarker for correlating the level of inflammation and therapeutic responses to be further validated.

Serial Fecal Calprotectin and Lactoferrin Measurements for Early Diagnosis of Pouchitis After Proctocolectomy for Ulcerative Colitis: Is Pouchoscopy No Longer Needed?

This editorial discusses the role of serial measurements of fecal calprotectin or fecal lactoferrin for the early detection of pouchitis in patients with ulcerative colitis having undergone procto-colectomy with ileo-pouch-anal anastomosis. Furthermore, the role of fecal calprotectin and fecal lactoferrin for the monitoring of pouchitis is highlighted.

Methods to determine intestinal permeability and bacterial translocation during liver disease

Liver disease is often times associated with increased intestinal permeability. A disruption of the gut barrier allows microbial products and viable bacteria to translocate from the intestinal lumen to extraintestinal organs. The majority of the venous blood from the intestinal tract is drained into the portal circulation, which is part of the dual hepatic blood supply. The liver is therefore the first organ in the body to encounter not only absorbed nutrients, but also gut-derived bacteria and pathogen associated molecular patterns (PAMPs). Chronic exposure to increased levels of PAMPs has been linked to disease progression during early stages and to infectious complications during late stages of liver disease (cirrhosis). It is therefore important to assess and monitor gut barrier dysfunction during hepatic disease. We review methods to assess intestinal barrier disruption and discuss advantages and disadvantages. We will in particular focus on methods that we have used to measure increased intestinal permeability and bacterial translocation in experimental liver disease models.

Dissecting Lewis score under the light of fecal calprotectin; an analysis of correlation of score components with calprotectin levels in capsule endoscopy

BACKGROUND

Lewis Score (LS) is an inflammatory score in small-bowel capsule endoscopy (SBCE). Fecal calprotectin (FC) is considered the non-invasive, 'gold standard' marker of gastrointestinal (GI) inflammation. Recently, we reported that LS shows only a moderate correlation with FC. In this study, we aim to evaluate which LS parameters have greater correlation with FC.

METHODS

A retrospective, two-center study; 74 patients who underwent SBCE within 7 (median 1.5) days from a FC measurement. LS was calculated; univariate and multivariate analyses were performed, investigating LS correlation with FC, and which LS parameters had stronger correlation coefficient (rs) with FC.

RESULTS

74 patients had an FC measurement within 7 days of their SBCE examination (median 22 time-interval: 1.5 days; IQR: 5). Coefficient rs between LS and FC was moderate (0.454). In univariate analysis, the variables that gave the strongest association with FC were: the higher tertile subscore for ulcer, the summative ulcer subscore, the higher tertile ulcer score (only with descriptors of ulcer size and number), the summative ulcer score (only with descriptors of ulcer size and number), and subscores including various combinations of the stenosis descriptors. In multivariate analysis, the only positive predictor for FC was the higher tertile ulcer subscore (only with descriptors of ulcer size and number).

CONCLUSION

LS shows only moderate correlation to FC. This is due to a) an inherent limitation of LS, and b) the notion of correlating the 2 parameters, and consideration should be given to development of a new, simplified (or composite) inflammation score/index for SBCE.

Colonic mucosal expression of heat-shock proteins may have a potential prognostic value in ulcerative colitis

BACKGROUND AND STUDY AIMS

Ulcerative colitis (UC) is a lifelong, chronic, progressive, and relapsing inflammatory disease. Endoscopy with biopsies is the mainstay in diagnosis and assessment. The development of biomarkers is important for the diagnosis and follow-up of UC. We investigated the expression of molecular chaperones/heat-shock proteins (HSP70 and HSP90) in relation to the grades of inflammation and dysplasia in patients with UC before and after treatment.

PATIENTS AND METHODS

A total of 104 naïve patients with UC of varying severity were admitted to the Department of Tropical Medicine and Infectious Diseases, Tanta University Hospital. Ten biopsies from the healthy mucosa of patients with irritable bowel syndrome (IBS) served as a control. Disease activity was assessed clinically using the Mayo score system. Endoscopic mucosal biopsies were taken at diagnosis and 6 months after treatment. Histopathological activity was graded for inflammation and dysplasia. Immunohistochemistry was used to determine the percentage of cells positive for HSPs. The results were expressed in a semiquantitative scale.

RESULTS

The expression of both HSP70 and HSP90 increased in patients with UC at the time of disease activity, and it decreased after treatment and remission. There was a significant correlation between the expression of both proteins and the grades of dysplasia as well as inflammation (P < 0.05). Strong expression of HSPs that persisted after treatment has been associated with cases of true dysplasia.

CONCLUSIONS

The results indicated that HSP70 and HSP90 had the potential for assessment of the activity and prognosis of UC. They can also predict the presence of dysplasia and differentiate it from reactive atypia. Larger studies are needed to confirm this diagnostic and prognostic value of HSPs.

Fecal calprotectin in diagnosis and clinical assessment of inflammatory bowel disease

The fecal neutrophil-derived biomarker calprotectin has several features of an ideal noninvasive test for detecting intestinal inflammation: it is simple, reliable, and low in cost. Its utility in differentiating inflammatory bowel diseases (IBDs) from functional conditions such as irritable bowel syndrome is well documented. Fecal calprotectin (FC) correlates closely with endoscopic activity of IBD. Emerging evidence suggest its usefulness in serial monitoring of disease activity and of therapy success in IBD. A low FC concentration predicts persistence of clinical remission especially in non-symptomatic ulcerative colitis and Crohn's colitis. Here, an overview is given to the current role of FC in diagnosis and clinical assessment of IBD.

Clinical utility of fecal neutrophil-derived biomarkers in evaluating activity of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a group of chronic, idiopathic intestinal diseases characterized by periods of remission and relapses. Evaluating the activity of IBD timely and accurately is crucial to guide treatment. The change of neutrophils in the intestinal tissue is correlated closely with the activity of IBD. This article reviews the clinical utility of fecal neutrophil-derived biomarkers in assessing the activity of IBD.

Role of HMGB1 as a suitable biomarker of subclinical intestinal inflammation and mucosal healing in patients with inflammatory bowel disease

BACKGROUND

Noninvasive biomarkers of high- and low-grade intestinal inflammation and of mucosal healing (MH) in patients with inflammatory bowel disease are currently lacking. We have recently shown that fecal high mobility group box 1 (HMGB1) protein is a novel biomarker of gut inflammation. We aimed at investigating in a mouse model if HMGB1 was able to foresee both a clinically evident and a subclinical gut inflammation and if its normalization indicated MH. We also aimed at confirming the results in patients with Crohn's disease (CD) and ulcerative colitis.

METHODS

C57BL6/J mice were treated with increasing doses of dextran sodium sulphate to induce colitis of different severity degrees; 28 with CD, 23 with ulcerative colitis, and 17 controls were also enrolled. Fecal HMGB1 was analyzed by enzyme-linked immunosorbent assay and immunoblotting.

RESULTS

Fecal HMGB1 increased by 5-, 11-, 18-, and 24-folds with dextran sodium sulphate doses of 0.25%, 0.50%, 1%, and 4%, respectively, showing that the protein detected a high-grade and a subclinical inflammation. After a recovery time of 4-week posttreatment, HMGB1 returned to control levels, paralleling MH. In patients, fecal HMGB1 significantly correlated with endoscopic indexes (Simple Endoscopic Score for Crohn's Disease [SES-CD], endoscopic Mayo subscore), but not with the disease activity indexes (Crohn's disease Activity Index, partial Mayo score).

CONCLUSIONS

Fecal HMGB1 is a robust noninvasive biomarker of clinically overt and subclinical gut inflammation; it can also be a surrogate marker of MH. We suggest the use of fecal HMGB1 to monitor the disease course and assess therapy outcomes in inflammatory bowel disease.

Clinical significance of fecal lactoferrin in screening of colorectal carcinoma

AIM: To investigate the clinical significance of fecal lactoferrin in the screening of colorectal carcinoma (CRC).

METHODS: Thirty-five healthy people as controls, 63 patients with CRC, 59 patients with intestinal polyps, and 50 patients with functional gastroenteropathy were recruited. All of the patients were asked to collect 5-10 g fecal sample during three days after colonoscopy. Enzyme-linked immunosorbent assay was used to determine fecal lactoferrin level.

RESULTS: The median fecal lactoferrin levels in CRC patients, healthy people, patients with intestinal polyps and those with functional gastroenteropathy were 59.30, 2.94, 17.63 and 3.22 μg/g, respectively; there was no significant difference in fecal lactoferrin levels between patients with functional gastroenteropathy and healthy people (P > 0.05), but statistical significances were observed between patients with functional gastroenteropathy and those with CRC or intestinal polyps (P < 0.01), between healthy people and patients with CRC or intestinal polyps (P < 0.01), and between patients with CRC and those with intestinal polyps (P < 0.01). The sensitivity, specificity, accuracy, Youden index, positive likelihood ratio and negative likelihood ratio of fecal lactoferrin for screening of CRC were 88.9%, 85.7%, 87.8%, 0.75, 6.22 and 0.13, respectively.

CONCLUSION: Fecal lactoferrin detection is a simple, non-invasive method for screening CRC, with a high sensitivity and specificity.