Fecal Biomarkers Research Articles

Fecal Eosinophil Cationic Protein Is a Diagnostic and Predictive Biomarker in Young Adults with Inflammatory Bowel Disease.

Background and Aims: Fecal biomarkers are important non-invasive markers monitoring disease activity in inflammatory bowel disease (IBD). We compared the significance of fecal eosinophil cationic protein (fECP) and fecal calprotectin (fCal). Methods: fECP and fCal were measured in patients with Crohn’s disease (CD, n = 97), ulcerative colitis (UC, n = 53), Clostridioides difficile infection (CDI, n = 9), primary food allergy (PFA, n = 11), pollen-associated food allergy (n = 25) and non-inflammatory controls (n = 78). Results were correlated with clinical and endoscopic IBD activity scores. Results: fECP was significantly elevated in CD, UC, CDI and PFA compared to controls. fCal was significantly increased in CD, UC and CDI. fECP had lower diagnostic accuracy than fCal (area under the curve (AUC) = 0.88) in differentiating between endoscopically active and inactive patients with IBD (AUC = 0.77, ROC analysis). In contrast to fCal, fECP correlated negatively with age and levels were also elevated in clinically and endoscopically inactive patients with IBD <45 years (endoscopically inactive IBD vs controls; AUC for fECP = 0.86; AUC for fCal = 0.62). However, in those patients with low inflammatory activity (fCal <250 mg/kg), high fECP indicated the need for treatment modification or surgery (fECP <200 µg/kg = 22%; 200–600 µg/kg = 44%; >600 µg/kg = 82%) at month 48 of follow-up. Conclusions: fECP is a diagnostic and prognostic marker in young patients with IBD in remission.

2235. Fecal Biomarkers for Clostridioides difficile Infection in Cancer Patients

BackgroundThe diagnosis of C. difficile infection (CDI) relies on using a nucleic acid amplification test (NAAT) followed by confirmatory toxin enzyme immunoassay (EIA). This study examined the utility of fecal biomarkers and C. difficile bacterial quantity (BQ) in differentiating patients with true infection (NAAT+/EIA+) from patients with colonization (NAAT+/EIA-) in the context of C. difficile ribotypes.MethodsWe studied 136 patients with diarrhea and CDI identified by NAAT in stools for which a confirmatory toxin A, B, EIA was performed. Fecal IL-8, IL-1β, calprotectin, and lactoferrin were studied by ELISA. C. difficile BQ was determined by 16S rRNA qPCR. Data were stratified according to cancer diagnosis into three groups [hematologic (H) n = 43, solid tumor (ST) n = 62, or stem cell transplant (SCT) n = 31].ResultsStools were EIA+ in 36/136 (26%) of the cohort. Although ST patients had a higher Charlson co-morbidity index when compared with the other two groups (P < 0.002), demographic characteristics and symptoms at the time of presentation were similar between groups regardless of EIA status. Most common ribotypes identified included F106 and F014-020. Ribotype distribution differed according to oncologic diagnosis as determined by the Shannon diversity index. There were fewer distinct C. difficile ribotypes in the SCT (n = 8) vs. ST (n = 15) and H (n = 15) groups (P < 0.001 and P < 0.002, respectively). BQ were higher in EIA+ than EIA- across all strata (log of BQ/mg 2.38 ± 1.49 vs. 0.92 ± 1.28, P > 0.001). Similarly, higher levels of fecal IL-8 (1.72 ± 1.9 vs. 0.83 ± 1.6 ng/mL), IL-1β (3.74 ± 13.7 vs.. 1.21 ± 4.6) and calprotectin (14.9 ± 27 vs. 6 ±1.8 ug/mL) levels were seen in EIA+ patients. While IL-8, IL-1β, and calprotectin were increased in EIA+ ST and H, no differences were seen in the SCT group. A sensitivity analysis using ROC curves, revealed that BQ resulted in a greater area under the curve than fecal markers of inflammation (A = 0.77, P < 0.001, 95% CI [0.67–0.86]).ConclusionIn this study in cancer and immunocompromised patients, C. difficile bacterial burden regardless of infecting ribotype and fecal cytokines showed to be a helpful assay in distinguishing true CDI from colonization. Disclosures All authors: No reported disclosures.

848 Comparison of Patient Preferences Between Stool Tests and Colonoscopy for Assessment of Disease Activity in Inflammatory Bowel Diseases

INTRODUCTION: Fecal biomarkers are being increasingly suggested as alternatives to colonoscopy for disease activity assessments. We aimed to assess patient preferences between fecal testing and colonoscopy for disease activity assessments. METHODS: Prospective interview of UC and CD patients from a single tertiary referral center. A hierarchy matrix survey was built to understand patient preferences around decision making when choosing between approaches (fecal testing or colonoscopy) for achieving a specific goal (monitoring disease activity) based on pre-set criteria (accuracy, preparation, pain, complications). Presumed accuracy of fecal biomarkers was set to 80-90%, and rates of colonoscopy related complication were set to 1 in 100 or 1 in 1,000. Pair wise analyses were used to identify determinants of patient preference and thresholds of acceptability to change preferences. RESULTS: N = 100, median age of 44 years (IQR 27-63) with median disease duration of 9 years (IQR 5-21). Disease activity at the time of survey was well distributed with 47% in clinical remission, 24% with mild and 29% with moderate-severe activity. Colonoscopy was the initial preference for 40% of patients and more often being preferred by CD patients (49% vs. 31%, P = 0.069). When choosing between fecal testing or colonoscopy for disease activity assessment, accuracy was significantly more important than preparation, pain, or complications (P &lt; 0.05), but preparation and pain were comparable to complications (P &gt; 0.20). After understanding the limitations in accuracy with fecal testing, 25 patients who initially chose fecal testing changed their preference to colonoscopy (P &lt; 0.001) and at the completion of the survey a total of 65% chose colonoscopy over fecal testing. If the fecal test was wrong at most 1 in 20 times (5%), 40% of patients who ultimately chose colonoscopy were willing to undergo fecal testing. If the fecal test was wrong at most 1 in 50 times (2%), 66% of patients who ultimately chose colonoscopy were willing to undergo fecal testing. CONCLUSION: Accuracy appears to be the most important criteria for IBD patients when choosing monitoring strategies, followed by pain/preparation and risk of complications. A significant number of patients changed their preferences to colonoscopy after learning more about the diagnostic accuracy of current fecal testing for disease monitoring. A high degree of confidence is required of fecal test results for patients to choose this strategy.

689 Early Improvement After Intravenous Ustekinumab Induction in Patients With Ulcerative Colitis: Results From the UNIFI Induction Trial

INTRODUCTION: The UNIFI induction study evaluated the efficacy and safety of ustekinumab (UST) in patients with moderately to severely active ulcerative colitis (UC) after a single intravenous infusion. In this analysis, we evaluated the rapidity of the onset of the treatment effect. METHODS: Eligible patients were randomly assigned to placebo (PBO) or UST 130 mg or ∼6 mg/kg. Patients recorded stool frequency and categorized rectal bleeding daily for the 7 days before each visit. Partial Mayo scores were calculated at baseline and Week 2 using the average of the stool frequency and rectal bleeding scores from the most recent consecutive 3-day period before the visit and the physician's global assessment score recorded at the visit. C-reactive protein (CRP) and fecal biomarkers were measured at baseline and Day 14. RESULTS: At baseline, the mean 3-day average daily stool frequency was 7.0 in the PBO group, 6.9 in the UST 130-mg group, and 7.0 in the UST ∼6-mg/kg group. Patients receiving UST showed greater reductions in the daily number of stools compared with PBO as soon as the first assessment time point at Day 7. Mean changes from baseline in daily stool frequency were -0.7 for PBO, -1.0 for UST 130-mg (P = 0.098), and -1.2 for UST ∼6-mg/kg group (P = 0.018) by Day 7, respectively, and -0.9, -1.6 (P &lt; 0.001), and -1.9 (P &lt; 0.001) by Day 13, respectively (Figure 1). Rectal bleeding scores at baseline and Week 2 are summarized in Figure 2. Patients receiving UST showed significantly greater improvement from baseline to Day 14 in partial Mayo score and CRP (Table, P &lt; 0.001 for all comparisons of UST vs PBO). Differences between the UST and PBO treatment groups in mean changes from baseline to Day 14 in fecal calprotectin did not reach significance (PBO -33.96 mg/kg, UST 130 mg 79.12 mg/kg [P = 0.875], UST ∼6 mg/kg -412.68 mg/kg [P = 0.152]). However, patients receiving UST showed significantly greater improvement in fecal calprotectin at Week 4 (mean changes from baseline: PBO -226.78 mg/kg, UST 130 mg -881.22 mg/kg [P = 0.013], UST ∼6 mg/kg -802.75 mg/kg [P &lt; 0.001]). Similar results were observed for fecal lactoferrin. CONCLUSION: The effect of UST began rapidly after induction, with symptomatic improvement and reduction of systemic inflammation seen as early as the first assessments at Days 7 and 14, respectively.

Fecal Calprotectin as a Marker of the Gut Immune System Activation Is Elevated in Parkinson's Disease.

IntroductionAlpha-synucleinopathy constituting a characteristic feature of Parkinson’s disease (PD) occurs at all levels of the brain-gut axis including the enteric nervous system (ENS). Lesions in the ENS may be connected with gut inflammation, increased intestinal permeability and dysmotility contributing to the pathogenesis of PD and its gastrointestinal manifestations.AimsTo evaluate fecal calprotectin and zonulin as biomarkers of gut inflammation and intestinal barrier dysfunction in PD patients.MethodsQuantitative evaluation of fecal biomarkers was performed by ELISA tests in 35 PD patients and 20 healthy controls. Additionally, patients filled out a short questionnaire concerning gastrointestinal symptoms.ResultsMedian fecal calprotectin level (μg/g) was significantly higher in PD patients compared to the controls: 54.5 (29.0–137.9) vs. 9.7 (5.2–23.3), p < 0.0001. Applying age-related reference ranges, the increased fecal calprotectin level was found in 43% of PD patients and in none of the control subjects (p < 0.001). No correlation between fecal calprotectin level and PD duration was observed. No statistically significant difference between the groups regarding zonulin level was found. The most frequent bowel symptoms reported by PD patients included constipation (69% of subjects), feeling of incomplete evacuation (51%), bloating (51%), abdominal pain (20%), and alternating bowel movement pattern (17%).ConclusionThe evaluation of fecal calprotectin level may be a useful tool to detect the signs of gut immune system activation present in a remarkable number of PD patients, also in the early stage of the disease. Calprotectin may constitute a critical link between amyloid formation and neuroinflammatory cascades serving as a prospective diagnostic and therapeutic target.

Development of an Index Score for Intestinal Inflammation-Associated Dysbiosis Using Real-World Stool Test Results

BackgroundGut microbiota play an important role in human health. However, the application of gut microbiome in regular clinical practice is limited by interindividual variations and complexity of test results.HypothesisIt is possible to address interindividual variation by using large data-based exploratory-pattern analysis.MethodsThe current study was conducted using a large data set (n = 173,221) of nonselective incoming patients’ test results from a stool test. The data set included assays for the detection of 24 selected commensal microorganisms and multiple biomarkers in feces. Patients were grouped based on their levels of inflammation biomarkers such as calprotectin, eosinophil protein X, and IgA. Group mean values of biomarkers and commensal microbes were used in an exploratory-pattern analysis for association from which an index score for intestinal inflammation-associated dysbiosis (IAD) was developed. The IAD score was evaluated in one questionnaire-based study (n = 7263) and one prospective case series study (n = 122) with patients of inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), and celiac disease.ResultsWe identified a microbial profile strongly associated with fecal inflammation biomarkers. Developed on the pattern of the microbial profile, the IAD score demonstrated a strong association with fecal inflammation biomarkers and was significantly different between patients with IBD and those with IBS or celiac disease.ConclusionUsing real-world data, we have developed a method to predict gut dysbiosis associated with different GI disease conditions. It may help clinicians simplify the process of interpreting gut microbial status and provide gut health assessment and treatment evaluation.

Proteomic Discovery of Stool Protein Biomarkers for Distinguishing Pediatric Inflammatory Bowel Disease Flares

Fecal calprotectin, the heterodimer of S100A8/S100A9, makes up ∼60% of neutrophil cytoplasmic protein content and is a canonical clinical biomarker of gut inflammation.1,2 Fecal calprotectin is commonly used to diagnose inflammatory bowel disease (IBD) and has an average sensitivity of 93% and specificity of 96%.1 For diagnosing pediatric IBD, calprotectin fecal tests have similar sensitivity (92%) but substantially less specificity (76%).1 Low specificity, especially in pediatric patients, means a high likelihood of false negative diagnoses, suggesting that a substantial number of active IBD cases remain undiagnosed and untreated. To improve on calprotectin as an effective IBD monitoring tool in pediatric populations, specificity must be increased. To develop an assay with higher specificity in pediatric patients, we identified a panel of multiple proteins that are present in both IBD flare and remission but have distinct abundance ranges between each condition. From a pilot cohort of 10 pediatric patients in states of either active disease or remission, we discovered and relatively quantified hundreds of stool proteins. Of these, our mass spectrometry-based study prioritized at least 5 that have potential to augment negative predictive power of mucosal-level inflammation alongside fecal biomarkers such as calprotectin.

Correlates of Gut Function in Children Hospitalized for Severe Acute Malnutrition, a Cross-sectional Study in Uganda.

Children with severe acute malnutrition (SAM) may have impaired intestinal function, which can result in malabsorption, diarrhoea, and poor growth. This study evaluated the gut function of children with SAM using fecal and blood biomarkers and assessed their correlates. A cross-sectional study, nested in a randomized trial (www.isrctn.com, ISRCTN 16454889), was conducted at Mulago hospital, Uganda among subgroups of 400 children with complicated SAM and 30 community controls. Gut function was evaluated by 5 biomarkers: plasma citrulline, fecal myeloperoxidase and fecal neopterin, bacterially derived 16S rRNA gene and internal transcribed Spacer region (ITS) specific for Candida spp. in blood. Compared with controls, children with SAM had lower median plasma citrulline (5.14 vs 27.4 μmol/L, P < 0.001), higher median fecal myeloperoxidase (18083 vs 7482 ng/mL, P = 0.001), and fecal neopterin (541 vs 210 nmol/L, P < 0.001). A higher blood concentration of 16S rRNA gene copy numbers was observed among children with SAM (95 vs 28 copies/μl, P = 0.05), whereas there was no difference in the blood concentration of Candida-specific ITS fragment.Among those with SAM, plasma citrulline was lower in children with edema, diarrhoea, dermatosis, and plasma C-reactive protein (CRP) >10 mg/L. Fecal neopterin was positively correlated with symptoms of fever and cough whereas it was negatively correlated with mid-upper arm circumference (MUAC), weight-for-height z score (WHZ), edema, and dermatosis. Children with complicated SAM seem to have impaired gut function characterized by reduced enterocyte mass, intestinal inflammation, and increased bacterial translocation.

Intestinal parasites at the Late Bronze Age settlement of Must Farm, in the fens of East Anglia, UK (9th century B.C.E.).

Little is known about the types of intestinal parasites that infected people living in prehistoric Britain. The Late Bronze Age archaeological site of Must Farm was a pile-dwelling settlement located in a wetland, consisting of stilted timber structures constructed over a slow-moving freshwater channel. At excavation, sediment samples were collected from occupation deposits around the timber structures. Fifteen coprolites were also hand-recovered from the occupation deposits; four were identified as human and seven as canine, using fecal lipid biomarkers. Digital light microscopy was used to identify preserved helminth eggs in the sediment and coprolites. Eggs of fish tapeworm (Diphyllobothrium latum and Diphyllobothrium dendriticum), Echinostoma sp., giant kidney worm (Dioctophyma renale), probable pig whipworm (Trichuris suis) and Capillaria sp. were found. This is the earliest evidence for fish tapeworm, Echinostoma worm, Capillaria worm and the giant kidney worm so far identified in Britain. It appears that the wetland environment of the settlement contributed to establishing parasite diversity and put the inhabitants at risk of infection by helminth species spread by eating raw fish, frogs or molluscs that flourish in freshwater aquatic environments, conversely the wetland may also have protected them from infection by certain geohelminths.

Serum Adipokines, Growth Factors, and Cytokines Are Independently Associated with Stunting in Bangladeshi Children.

Growth in young children is controlled through the release of several hormonal signals, which are affected by diet, infection, and other exposures. Stunting is clearly a growth disorder, yet limited evidence exists documenting the association of different growth biomarkers with child stunting. This study explored the association between different growth biomarkers and stunting in Bangladeshi children. A quasi-experimental study was conducted among 50 stunted (length-for-age Z-score (LAZ) < −2 SD) and 50 control (LAZ ≥ −2 SD) children, aged 12–18 months, residing in a Bangladeshi slum. The enrolled stunted children received an intervention package, which included food supplementation for three months, psychosocial stimulation for six months, and routine clinical care on community nutrition center at the study field site. The controls received routine clinical care only. All children were clinically screened over the study period. Length, weight, fasting blood and fecal biomarkers were measured. All biomarkers levels were similar in both groups except for oxyntomodulin at enrolment. Leptin (adjusted odds ratio, AOR: 4.0, p < 0.01), leptin–adiponectin ratio (AOR 5.07 × 108, p < 0.01), insulin-like growth factor-1 (IGF-1) (AOR 1.02, p < 0.05), and gamma interferon (IFN-γ) (AOR 0.92, p < 0.05) levels were independently associated with stunting at enrolment. Serum leptin, leptin–adiponectin ratio, interleukin-6 (IL-6), IL-10, tumor necrosis factor-alpha (TNF-α), and fecal alpha-1-antitrypsin (AAT) levels increased significantly (p < 0.001), while IFN-γ levels significantly decreased among stunted children after six months of intervention. Leptin, leptin–adiponectin ratio, IGF-1, and IFN-γ are independently associated with stunting in Bangladeshi children. This trial was registered at clinicaltrials.gov as NCT02839148.

Significance of Conducting 2 Types of Fecal Tests in Patients With Ulcerative Colitis

We compared the diagnostic accuracy of the fecal calprotectin (FCP) test vs the fecal immunochemical blood test (FIT) in determining the endoscopic severity and predicting outcomes of patients with ulcerative colitis (UC). We performed a nationwide study of 879 patients with UC, enrolled at medical centers across Japan, from March 2015 to March 2017. We collected data on fecal biomarkers, endoscopic severities, and other clinical indices from Cohort 1 (n = 427) and assessed the diagnostic accuracy of FCP measurement and FIT results in determining clinical severity, based on Mayo score, and endoscopic remission, based on Mayo endoscopic sub-score (MES) or UC endoscopic index of severity. We also followed 452 patients in clinical remission from UC (Cohort 2) for 12 months and evaluated the associations of FCP levels and FIT results with clinical recurrence. The levels of FCP and FIT each correlated with the MES and UC endoscopic index of severity. There were no significant differences in the areas under the curve of FCP vs FIT in distinguishing patients with MES≤1 from those with MES≥2 (P = .394) or in distinguishing patients with MES=0 from those with MES≥1 (P = .178). Among 405 patients in clinical remission at baseline, 38 (9.4%) had UC recurrences within 3 months and 90 (22.2%) had recurrences within 12 months. FCP≥146 mg/kg (hazard ratio [HR], 4.83; 95% confidence interval [CI], 2.80-8.33) and FIT≥77 ng/mL (HR, 2.92; 95% CI, 1.76-4.83) were independently associated with clinical recurrence within 12 months. UC recurred within 12 months in 69% of patients with levels of FCP≥146 mg/kg and FIT ≥77 ng/mL; this value was significantly higher than the rate of recurrence in patients with levels of FCP≥146 mg/kg and FIT <77 ng/mL (31.5%, P < .001) or patients with levels of FCP<146 mg/kg and FIT ≥77 ng/mL (30.0%, P< .001). In a nationwide study of patients with UC in Japan, we found that the level of FCP and FIT could each identify patients with endoscopic markers of disease severity (MES≥2). The combination of FCP and FIT results can identify patients in remission who are at risk for disease recurrence. Clinical Trials Registry no: UMIN000017650 (http://www.umin.ac.jp/ctr/).

The human microbiota is associated with cardiometabolic risk across the epidemiologic transition.

Oral and fecal microbial biomarkers have previously been associated with cardiometabolic (CM) risk, however, no comprehensive attempt has been made to explore this association in minority populations or across different geographic regions. We characterized gut- and oral-associated microbiota and CM risk in 655 participants of African-origin, aged 25–45, from Ghana, South Africa, Jamaica, and the United States (US). CM risk was classified using the CM risk cut-points for elevated waist circumference, elevated blood pressure and elevated fasted blood glucose, low high-density lipoprotein (HDL), and elevated triglycerides. Gut-associated bacterial alpha diversity negatively correlated with elevated blood pressure and elevated fasted blood glucose. Similarly, gut bacterial beta diversity was also significantly differentiated by waist circumference, blood pressure, triglyceridemia and HDL-cholesterolemia. Notably, differences in inter- and intra-personal gut microbial diversity were geographic-region specific. Participants meeting the cut-points for 3 out of the 5 CM risk factors were significantly more enriched with Lachnospiraceae, and were significantly depleted of Clostridiaceae, Peptostreptococcaceae, and Prevotella. The predicted relative proportions of the genes involved in the pathways for lipopolysaccharides (LPS) and butyrate synthesis were also significantly differentiated by the CM risk phenotype, whereby genes involved in the butyrate synthesis via lysine, glutarate and 4-aminobutyrate/succinate pathways and LPS synthesis pathway were enriched in participants with greater CM risk. Furthermore, inter-individual oral microbiota diversity was also significantly associated with the CM risk factors, and oral-associated Streptococcus, Prevotella, and Veillonella were enriched in participants with 3 out of the 5 CM risk factors. We demonstrate that in a diverse cohort of African-origin adults, CM risk is significantly associated with reduced microbial diversity, and the enrichment of specific bacterial taxa and predicted functional traits in both gut and oral environments. As well as providing new insights into the associations between the gut and oral microbiota and CM risk, this study also highlights the potential for novel therapeutic discoveries which target the oral and gut microbiota in CM risk.

Association of atopic dermatitis with obesity via a multi-omics approach: A protocol for a case-control study.

Introduction:Several studies have found that obesity is associated with atopic dermatitis (AD); however, the mechanisms underlying the association are largely unknown. This study aims to assess the association of AD with obesity in the Korean population and verify its mechanism via a multi-omics analysis.Methods and analysis:A case–control study will be conducted in the Republic of Korea. A total of 80 subjects, aged 4 to 12 years, matched for age and sex, with body mass index at or above the 85th percentile or at or below the 25th percentile, will be included. Subjects will be assigned to the following 4 groups: obese/overweight with AD, normal/underweight with AD, obese/overweight control, and normal/underweight control. Serum metabolome and immune biomarkers, as well as fecal metabolome and microbiome biomarkers, will be analyzed. Serum eosinophil cationic protein, total serum Immunoglobulin E (IgE), and specific IgE will be analyzed to assess allergic tendency. The SCORing of AD index, the children's dermatology life quality index, body composition analysis, and the Korean gastrointestinal symptom rating scale will be obtained to assess the disease status and severity of the subjects.Discussion:The findings of this study are expected to provide evidence of an association between AD and obesity via a gut microbiome-metabolome-immune mechanism. Therefore, it may improve future management strategies for AD.Trial registration:This study has been registered at the Korean National Clinical Trial Registry, Clinical Research Information Service (KCT0003630).

Identification of Fecal Microbiota Biomarkers of Spondyloarthritis in Patients Suffering From Crohn's Disease.

Identification of Fecal Microbiota Biomarkers of Spondyloarthritis in Patients Suffering From Crohn's Disease.

Development and Validation of a Fecal Extraction Procedure for the Assessment of Multiple Fecal Biomarkers of Intestinal Inflammation (P13-025-19)

ObjectivesFecal biomarkers have emerged as an important tool to assess intestinal inflammation and permeability. Commonly measured biomarkers include calprotectin (CP), myeloperoxidase (MPO), alpha-1-antitrypsin (AAT) and neopterin (NEO). We sought to develop a simple, fast and cost-effective single extraction procedure for use in determining all four biomarkers of interest. The applicability and sensitivity of this procedure for use in healthy adults was examined. MethodsSample extraction buffers and methods including sample weight, dilution, homogenization and centrifugation were all considered in the development of a single extraction procedure. An extraction buffer that included phosphate-buffered saline, phenylmethylsulfonyl fluoride, bovine serum albumin and Tween 20 was used to extract fecal samples. To assess the applicability and sensitivity of the single extraction procedure, concentrations of CP, MPO, AAT and NEO were measured using commercially available sandwich ELISA kits, according to manufacturer’s instructions. ResultsCP, MPO and AAT concentrations were measured in fecal samples of healthy adults (aged 50–80 years, n = 85) and found to be comparable to findings of previously published studies in healthy populations. Mean concentrations of CP and AAT were 3.6 ± 3.8 μg/g of wet weight (range 0.14–18.0 μg/g) and 2.3 ± 0.73 μg/g (range 0.76–5.2 μg/g), respectively. Mean fecal MPO concentrations were 135 ± 24 ng/g (range 3–1290 ng/g). NEO concentrations were examined in a subset of healthy adults (n = 10), with mean concentrations of 18 ± 1 ng/g (range 17–20 ng/g). ConclusionsWe demonstrated the efficacy of a single extraction procedure used to assess multiple fecal biomarkers of intestinal inflammation. This simple, fast and inexpensive extraction method will facilitate the determination of multiple fecal biomarkers which is critical in validating their use as clinical or predictive biomarkers of intestinal inflammation. Funding SourcesSupported by the U.S. Department of Agriculture – Agricultural Research Service (ARS), under Agreement No. 58–1950-4–003, the Bill & Melinda Gates Foundation and Canadian Institutes of Health Research Postdoctoral Fellowship.

Intervening Effects of Total Alkaloids of Corydalis saxicola Bunting on Rats With Antibiotic-Induced Gut Microbiota Dysbiosis Based on 16S rRNA Gene Sequencing and Untargeted Metabolomics Analyses.

Gut microbiota dysbiosis induced by antibiotics is strongly connected with health concerns. Studying the mechanisms underlying antibiotic-induced gut microbiota dysbiosis could help to identify effective drugs and prevent many serious diseases. In this study, in rats with antibiotic-induced gut microbiota dysbiosis treated with total alkaloids of Corydalis saxicola Bunting (TACS), urinary and fecal biochemical changes and cecum microbial diversity were investigated using 16S rRNA gene sequencing analysis and untargeted metabolomics. The microbial diversity results showed that 10 genera were disturbed by the antibiotic treatment, and two of them were obviously restored by TACS. The untargeted metabolomics analysis identified 34 potential biomarkers in urine and feces that may be the metabolites that are most related to the mechanisms underlying antibiotic-induced gut microbiota dysbiosis and the therapeutic effects of TACS treatment. The biomarkers were involved in six metabolic pathways, comprising pathways related to branched-chain amino acid (BCAA), bile acid, arginine and proline, purine, aromatic amino acid, and amino sugar and nucleotide sugar metabolism. Notably, there was a strong correlation between these metabolic pathways and two gut microbiota genera (g__Blautia and g__Intestinibacter). The correlation analysis suggested that TACS might synergistically affect four of these metabolic pathways (BCAA, bile acid, arginine and proline, and purine metabolism), thereby modulating gut microbiota dysbiosis. Furthermore, we performed a molecular docking analysis involving simulating high-precision docking and using molecular pathway maps to illuminate the way that ligands (the five main alkaloid components of TACS) act on a complex molecular network, using CYP27A1 (a key enzyme in the bile acid synthesis pathway) as the target protein. This study provides a comprehensive overview of the intervening effects of TACS on the host metabolic phenotype and gut microbiome in rats with gut microbiota dysbiosis, and it presents new insights for the discovery of effective drugs and the best therapeutic approaches.

Environmental risks associated with contaminants of legacy and emerging concern at European aquaculture areas

The contamination of marine ecosystems by contaminants of emerging concern such as personal care products or per- and polyfluoroalkyl substances is of increasing concern. This work assessed the concentrations of selected contaminants of emerging concern in water and sediment of European aquaculture areas, to evaluate their co-variation with legacy contaminants (polycyclic aromatic hydrocarbons) and faecal biomarkers, and estimate the risks associated with their occurrence. The 9 study sites were selected in 7 European countries to be representative of the aquaculture activities of their region: 4 sites in the Atlantic Ocean and 5 in the Mediterranean Sea. Musks, UV filters, preservatives, per- and polyfluoroalkyl substances and polycyclic aromatic hydrocarbons were detected in at least one of the sites with regional differences. While personal care products appear to be the main component of the water contamination, polycyclic aromatic hydrocarbons were mostly found in sediments. As expected, generally higher levels of personal care products were found in sewage impacted sites, urbanised coasts and estuaries. The risk assessment for water and sediment revealed a potential risk for the local aquatic environment from contaminants of both legacy and emerging concern, with a significant contribution of the UV filter octocrylene. Despite marginal contributions of per- and polyfluoroalkyl substances to the total concentrations, PFOS (perfluorooctane sulfonate) aqueous concentrations combined to its low ecotoxicity thresholds produced significant hazard quotients indicating a potential risk to the ecosystems.

Mo1636 – The Addition of Other Faecal Biomarkers to Immunological Faecal Occult Blood Test is Not Effective to Avoid Normal Colonoscopies in a Colorectal Cancer Screening Program

Mo1636 – The Addition of Other Faecal Biomarkers to Immunological Faecal Occult Blood Test is Not Effective to Avoid Normal Colonoscopies in a Colorectal Cancer Screening Program

Reduction of faecal immunochemical test false-positive results using a signature based on faecal bacterial markers.

Colorectal cancer is the second commonest cause of cancer mortality. Some countries are implementing colorectal cancer screening to detect lesions at an early stage using non-invasive tools like the faecal immunochemical test. Despite affordability, this test shows a low sensitivity for precancerous lesions and a low positive predictive value for colorectal cancer, resulting in a high false-positive rate. To develop a new, non-invasive colorectal cancer screening tool based on bacterial faecal biomarkers, which in combination with the faecal immunochemical test, could allow a reduction in the false-positive rate. This tool is called risk assessment of intestinal disease for colorectal cancer (RAID-CRC). We performed both the faecal immunochemical test and the bacterial markers analysis (RAID-CRC test) in stool samples from individuals with normal colonoscopy (167), non-advanced adenomas (88), advanced adenomas (30) and colorectal cancer (48). All the participants showed colorectal cancer-associated symptoms. Performance of the faecal immunochemical test for advanced neoplasia (ie advanced adenoma and colorectal cancer) was determined by using the cut-off value established in Catalonia (20µg haemoglobin/g of faeces) for a population-based screening approach. Sensitivity and specificity values of 83% and 80%, respectively, and positive and negative predictive values of 56% and 94%, respectively, were obtained. When both the immunological and the biological analysis were combined, the corresponding values were 80% and 90% for sensitivity and specificity, respectively, and 70% and 94% for positive and negative predictive values, respectively, resulting in a 50% reduction of the false-positive rate. RAID-CRC test allows a substantial reduction in the faecal immunochemical test false-positive results (50%) in a symptomatic population. Further validation is indicated in a colorectal cancer-screening scenario.

Unexplained inflammation in end-stage kidney disease: Is the combination of enhanced gastrointestinal permeability and reticuloendothelial dysfunction its cause?

Unexplained chronic inflammation is prevalent in end-stage kidney disease, and contributes toward accelerated cardiovascular disease, and premature death. The source of inflammation is unclear, although increased gastrointestinal permeability is a likely contributory factor. Whether a "leaky" gut leads to penetration of the systemic circulation by gut-derived pathogens is at least partly dependent on Kupffer cell function. These resident liver macrophages are an important part of the reticuloendothelial system (RES), and there is evidence for Kupffer cell and reticuloendothelial dysfunction in chronic kidney disease. These observations are compatible with the inflammatory milieu of chronic kidney disease being of gut origin. Measuring gut permeability in chronic kidney disease is challenging. Use of fecal biomarkers and other novel serum biomarkers represent potential alternative tools. One such marker is (1-3)-Beta-D-glucan, a polysaccharide constituent of many fungal, bacterial, and plant cell walls; levels of (1-3)-Beta-D-glucan are elevated in hemodialysis patients. Gastrointestinal permeability and impaired removal by the RES may contribute to these high levels, suggesting potential importance as a biomarker. High levels of (1-3)-Beta-D-glucan also falsely elevate endotoxin measurements. Measuring the contribution of gastrointestinal permeability and RES dysfunction to systemic inflammation may be an important step in designing therapies to reduce systemic inflammation in chronic kidney disease.