Calprotectin, a faecal marker of organic gastrointestinal abnormality

Serum calprotectin as a marker of neonatal sepsis: a hospital-based cross-sectional diagnostic study

Background

Despite significant advances in neonatal care, neonatal sepsis remains a major contributor to mortality, morbidity, and protracted hospitalization. The development of early possible diagnostic indicators for newborn sepsis is critical. Since calprotectin participates in major biological processes, it could be a diagnostic marker for infection/inflammation. This study aimed to estimate serum calprotectin in neonates with clinical sepsis. In addition, we compared serum calprotectin with standard sepsis markers and serum procalcitonin to evaluate its diagnostic accuracy.

Methods

A hospital-based cross-sectional diagnostic study of neonates identified with clinical sepsis using standard criteria was carried out. We compared estimated serum calprotectin levels to serum procalcitonin levels and conventional sepsis markers (leucocyte count, blood culture, immature to total neutrophil ratio, and C- reactive protein). We used SPSS version 25 to analyze the data. To examine diagnostic accuracy and determine a cut-off value for serum calprotectin, we used the receiver operating characteristics (ROC) curve.

Results

Of the 83 subjects included, 36.5% (30/83) had blood culture positive status, the median value of serum calprotectin being 0.93 ng/ml (0.67 to 1.3). Respiratory, cardiovascular, and gastrointestinal instabilities were present in 67.5% (56/83), 59% (49/83), and 50.1% (42/83) cases, respectively. The median values of serum calprotectin, procalcitonin, TLC, and I/T ratio between neonates withpositive blood culturesand negative culturesdid not differ significantly.. On ROC, calprotectin was not predictive for blood culture positivity (sensitivity: 50%; specificity: 44% at 0.83 ng/ml of serum calprotectin) and C-reactive protein (CRP) levels (sensitivity: 57%; specificity: 67% at serum calprotectin levels of 0.89 ng/ml). However, compared with serum procalcitonin, serum calprotectin at 1.2 ng/ml had sensitivity and specificity of 60% and 73%, respectively.

Conclusions

Serum calprotectin did not show a distinct advantage over the existing sepsis markers. Serum calprotectin level at 1.2 ng/ml had a sensitivity and specificity of 60% and 73%, respectively, compared to serum procalcitonin in detecting neonatal sepsis.

Elevated Fecal Calprotectin Accompanied by Intestinal Neutrophil Infiltration and Goblet Cell Hyperplasia in a Murine Model of Multiple Sclerosis

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system caused by myelin-specific autoreactive T cells. We previously demonstrated intestinal barrier disruption and signs of inflammation in experimental autoimmune encephalomyelitis (EAE), a model of MS. Fecal calprotectin is a disease activity biomarker in inflammatory bowel diseases, released by neutrophils in response to inflammation. We aimed to further investigate EAE manifestations in the gastrointestinal tract and to determine whether calprotectin is a useful biomarker of intestinal inflammation in EAE. Calprotectin was analyzed in feces, cecal contents, and plasma of EAE mice. Infiltrating neutrophils and goblet cells were investigated in different parts of the gastrointestinal tract before the onset of neurological symptoms and during established disease. We found increased calprotectin levels in feces, cecal content, and plasma preceding EAE onset that further escalated during disease progression. Increased neutrophil infiltration in the intestinal tissue concomitant with IL-17 expression and myeloperoxidase activity was found to correlate well with clinical activity. Increased goblet cells in the intestine, similar to irritable bowel syndrome (IBS), were also observed. The results suggest calprotectin as a good biomarker of gastrointestinal inflammation in EAE and the potential of this model as a useful animal model for IBS.

Verification of the fCAL turbo immunoturbidimetric assay for measurement of the fecal calprotectin concentration in dogs and cats

The concentration of calprotectin in feces (fCal) is a clinically useful marker of chronic gastrointestinal inflammation in humans and dogs. No commercial assay is widely available to measure fCal in small animal medicine, to date. Thus, we verified the immunoturbidimetric fCAL turbo assay (Bühlmann) of fCal for canine and feline fecal extracts by determining linearity, spiking and recovery, and intra-assay and inter-assay variability. We determined RIs, temporal variation over 3 mo, and effect of vaccination and NSAID treatment. Observed:expected (O:E) ratios (x̄ ± SD) for serial dilutions of feces were 89–131% (106 ± 9%) in dogs and 77–122% (100 ± 12%) in cats. For spiking and recovery, the O:E ratios were 90–118% (102 ± 11%) in dogs and 83–235% (129 ± 42%) in cats. Intra- and inter-assay CVs for canine samples were ≤19% and ≤7%, and for feline samples ≤22% and ≤21%. Single-sample RIs were <41 μg/g for dogs and <64 μg/g for cats. With low reciprocal individuality indices, using population-based fCal RIs is appropriate, and moderate fCal changes between measurements (dogs 44.0%; cats: 43.2%) are considered relevant. Cats had significant (but unlikely relevant) fCal increases post-vaccination. Despite individual fCal spikes, no differences were seen during NSAID treatment. The fCAL turbidimetric assay is linear, precise, reproducible, and sufficiently accurate for measuring fCal in dogs and cats. Careful interpretation of fCal concentrations is warranted in both species during the peri-vaccination period and for some patients receiving NSAID treatment.

Biomarkers of gut injury in neonates - where are we in predicting necrotising enterocolitis?

Despite advances in neonatal care Necrotising Enterocolitis (NEC) continues to have a significant mortality and morbidity rate, and with increasing survival of those more immature infants the population at risk of NEC is increasing. Ischaemia, reperfusion, and inflammation underpin diseases affecting intestinal blood flow causing gut injury including Necrotising Enterocolitis. There is increasing interest in tissue biomarkers of gut injury in neonates, particularly those representing changes in intestinal wall barrier and permeability, to determine whether these could be useful biomarkers of gut injury. This article reviews current and newly proposed markers of gut injury, the available literature evidence, recent advances and considers how effective they are in clinical practice. We discuss each biomarker in terms of its effectiveness in predicting NEC onset and diagnosis or predicting NEC severity and then those that will aid in surveillance and identifying those infants are greatest risk of developing NEC.

The Role of Segmented Filamentous Bacteria in Immune Barrier Maturation of the Small Intestine at Weaning

The microbiological, physical, chemical, and immunological barriers of the gastrointestinal tract (GIT) begin developing in utero and finish maturing postnatally. Maturation of these barriers is essential for the proper functioning of the GIT. Maturation, particularly of the immunological barrier, involves stimulation by bacteria. Segmented filamentous bacteria (SFB) which are anaerobic, spore-forming commensals have been linked to immune activation. The presence and changes in SFB abundance have been positively correlated to immune markers (cytokines and immunoglobulins) in the rat ileum and stool samples, pre- and post-weaning. The abundance of SFB in infant stool increases from 6 months, peaks around 12 months and plateaus 25 months post-weaning. Changes in SFB abundance at these times correlate positively and negatively with the production of interleukin 17 (IL 17) and immunoglobulin A (IgA), respectively, indicating involvement in immune function and maturation. Additionally, the peak in SFB abundance when a human milk diet was complemented by solid foods hints at a diet effect. SFB genome analysis revealed enzymes involved in metabolic pathways for survival, growth and development, host mucosal attachment and substrate acquisition. This narrative review discusses the current knowledge of SFB and their suggested effects on the small intestine immune system. Referencing the published genomes of rat and mouse SFB, the use of food substrates to modulate SFB abundance is proposed while considering their effects on other microbes. Changes in the immune response caused by the interaction of food substrate with SFB may provide insight into their role in infant immunological barrier maturation.

Predictive and Diagnostic Biomarkers of Anastomotic Leakage: A Precision Medicine Approach for Colorectal Cancer Patients

Development of an anastomotic leak (AL) following intestinal surgery for the treatment of colorectal cancers is a life-threatening complication. Failure of the anastomosis to heal correctly can lead to contamination of the abdomen with intestinal contents and the development of peritonitis. The additional care that these patients require is associated with longer hospitalisation stays and increased economic costs. Patients also have higher morbidity and mortality rates and poorer oncological prognosis. Unfortunately, current practices for AL diagnosis are non-specific, which may delay diagnosis and have a negative impact on patient outcome. To overcome these issues, research is continuing to identify AL diagnostic or predictive biomarkers. In this review, we highlight promising candidate biomarkers including ischaemic metabolites, inflammatory markers and bacteria. Although research has focused on the use of blood or peritoneal fluid samples, we describe the use of implantable medical devices that have been designed to measure biomarkers in peri-anastomotic tissue. Biomarkers that can be used in conjunction with clinical status, routine haematological and biochemical analysis and imaging have the potential to help to deliver a precision medicine package that could significantly enhance a patient's post-operative care and improve outcomes. Although no AL biomarker has yet been validated in large-scale clinical trials, there is confidence that personalised medicine, through biomarker analysis, could be realised for colorectal cancer intestinal resection and anastomosis patients in the years to come.

Faecal Inflammatory Biomarkers and Gastrointestinal Symptoms after Bariatric Surgery: A Longitudinal Study

Background

Bariatric surgery induces various gastrointestinal (GI) modifications. We performed the first study longitudinally assessing the effect of bariatric surgery on faecal inflammatory biomarker levels and its relation with GI complaints.

Method

Faecal calprotectin, lactoferrin, and calgranulin-C levels were determined in 41 patients (34 Roux-en-Y [RYGB], 7 sleeves) before and at 6-16 weeks, 6 months, and 1 year after surgery. Changes in biomarker levels and percentage of patients above reference value were determined. Gastrointestinal symptom rating scale (GSRS) was used to assess GI complaints at corresponding time points. The postoperative relation between GSRS score and biomarker levels above reference value was investigated.

Results

After RYGB, median calprotectin levels are significantly higher (>188, 104-415 μg/g) than before surgery (40, 19-78 μg/g; p < 0.001), and over 90% of patients have levels above reference value 1 year after surgery. Median lactoferrin was 0.4 (0.2-1.6) μg/g before, and >5.9 (1.8-13.6) μg/g after surgery (p < 0.001). Median calgranulin-C levels remained far below the reference value and were 0.13 (0.05-0.24) μg/g before and <0.23 (0.06-0.33) μg/g after surgery. Similar results were found after sleeve gastrectomy. No difference was seen in GSRS score for patients with calprotectin and lactoferrin levels above reference values.

Conclusion

Faecal inflammatory biomarkers calprotectin and lactoferrin, but not calgranulin-C, rise above reference values shortly after bariatric surgery and remain elevated in the majority of patients. The discrepancy between calprotectin and calgranulin-C levels suggests no GI inflammation. Furthermore, patients after RYGB with biomarkers above the population reference value do not seem to have more GI complaints.

Gut Alterations in Septic Patients: A Biochemical Literature Review

BACKGROUND

Sepsis is a life-threatening organ dysfunction with high mortality and morbidity rate and with the disease progression many alterations are observed in different organs. The gastrointestinal tract is often damaged during sepsis and septic shock and main symptoms are related to increased permeability, bacterial translocation and malabsorption. These intestinal alterations can be both cause and effect of sepsis.

OBJECTIVE

The aim of this review is to analyze different pathways that lead to intestinal alteration in sepsis and to explore the most common methods for intestinal permeability measurement and, at the same time to evaluate if their use permit to identify patients at high risk of sepsis and eventually to estimate the prognosis.

MATERIAL AND METHODS

The peer-reviewed articles analyzed were selected from PubMed databases using the keywords "sepsis" "gut alteration", "bowel permeability", "gut alteration", "bacterial translocation", "gut permeability tests", "gut inflammation". Among the 321 papers identified, 190 articles were selected, after title - abstract examination and removing the duplicates and studies on pediatric population,only 105 articles relating to sepsis and gut alterations were analyzed.

RESULTS

Integrity of the intestinal barrier plays a key role in the preventing of bacterial translocation and gut alteration related to sepsis. It is obvious that this dysfunction of the small intestine can have serious consequences and the early identification of patients at risk - to develop malabsorption or already malnourished - is very recommended to increase the survivor rate. Until now, in critical patients, the dosage of citrullinemia is easily applied test in clinical setting, in fact, it is relatively easy to administer and allows to accurately assess the functionality of enterocytes.

CONCLUSION

The sepsis can have an important impact on the gastrointestinal function. In addition, the alteration of the permeability can become a source of systemic infection. At the moment, biological damage markers are not specific, but the dosage of LPS, citrulline, lactulose/mannitol test, FABP and fecal calprotectin are becoming an excellent alternative with high specificity and sensitivity.

Faecal calprotectin and gut microbiota do not predict enteropathy in very preterm infants

Aim

Very preterm birth is associated with a high risk of enteropathies. Diagnosis is challenging, especially in mild forms, leading to unnecessary periods of cessation of enteral feeding. This study aimed at establishing a prognosis score of enteropathy combining clinical parameters and faecal calprotectin concentration.

Methods

This prospective multicentric study included preterm neonates born at a gestational age of 33 weeks or less. Stools were collected weekly until hospital discharge, and daily in case of digestive events for calprotectin measurement (ELISA and immunochromatography) and microbiota analyses (16S rRNA gene sequencing).

Results

Among the 121 neonates included, 21 experienced at least one episode of enteropathy, mainly mild forms. By ELISA testing, median faecal calprotectin was 88 (8‐798) µg/g faeces. No statistically significant association was found between the outset of enteropathy and maternal and neonatal characteristics, and calprotectin levels. The agreement between ELISA and immunochromatography assay was moderate (intra‐class correlation coefficient 0.58, 95%CI [0.47‐0.66]). Comparison of species diversity and relative bacterial abundance profiles between infants with or without enteropathy revealed no specific alterations associated with enteropathy.

Conclusion

The study failed to propose a prognostic score of enteropathy, probably due the large inter‐ and intra‐individual variability of faecal calprotectin in very preterm neonates.

Correlation between Fecal Calprotectin Levels in Meconium and Vitamin D Levels in Cord Blood: Association with Intestinal Distress

We aimed to investigate the correlation between vitamin D status in cord blood and fecal calprotectin concentrations in meconium, and also find their association with intestinal distress symptoms during the first two weeks of life. Two hundred and twenty-eight newborns were enrolled in the study who were delivered at Kyungpook National University Children’s Hospital between July 2016 and August 2017. The first passed meconium samples were collected for fecal calprotectin analysis. Intestinal distress involved infants with necrotizing enterocolitis (NEC) and other feeding interruption signs. The median gestational age of the population was 37.0 (34.3–38.4) weeks, and the median birth weight was 2635 (2100–3268) g. The median fecal calprotectin levels in meconium were 134.1 (55.6–403.2) μg/g (range: 11.5–2000 μg/g) and the median 25-hydroxyvitamin D (25-OHD) concentrations in cord blood were 21.0 (15.5–28.8) ng/mL. Sixty infants (26.3%) had intestinal distress, including four patients (1.8%) diagnosed as having NEC. Higher fecal calprotectin concentrations (398.2 (131.8–900.2) μg/g vs. 105.6 (39.4–248.5) μg/g, p < 0.001) and lower 25-OHD levels (17.9 (12.8–22.1) ng/mL vs. 23.2 (17.2–33.0) ng/mL, p < 0.001) were found in infants with intestinal distress compared to infants without intestinal distress. The cut-off value was set at 359.8 μg/g with a sensitivity of 0.53 and a specificity of 0.82 for the development of intestinal distress in the first two weeks of life. Serum 25-OHD levels in cord blood were inversely correlated with fecal calprotectin concentrations in meconium.

Does Human Milk Fortifier Affect Intestinal Inflammation in Preterm Infants?

Background: Fecal calprotectin, a recognized marker of intestinal inflammation, is derived from neutrophil migration to a site of inflammation. Introduction of bovine-based human milk fortifier containing intact protein in preterm infants is associated with an increase in fecal calprotectin suggestive of intestinal inflammation. Newer fortifiers contain protein hydrolysates in place of intact protein. Objective: To measure fecal calprotectin in human milk-fed preterm infants before and after human milk fortification using a fortifier containing hydrolyzed protein. Methods: Serial stool samples were collected from 24 infants beginning at the first week to 60 days postnatal age. To compare the effect of human milk fortification, samples collected before and after fortification were compared. Infant demographics, diet, postnatal morbidities, and maternal characteristics were recorded. Results: A total of 401 stool samples were collected from 24 study infants who had a birth weight of 993 ± 277 g (mean ± standard deviation), gestational age 27.5 ± 2.8 weeks, and fortifier initiation at 14 days. Median fecal calprotectin before and after fortification were similar. Calprotectin levels were not correlated with birth weight or gestational age but were inversely correlated with postnatal age (p = 0.005), use of fortifier (p < 0.001), receipt of antibiotics antenatally (p = 0.007) and postnatally (p = 0.008). After adjusting for postnatal age, calprotectin levels were significantly lower following receipt of fortifier (p < 0.001) and postnatal antibiotics (p < 0.001). Conclusions: The feeding of protein hydrolysate-containing human milk fortifiers does not appear to be associated with increases in a marker of intestinal inflammation.

Increase of Neutrophil Activation Markers in Venous Thrombosis-Contribution of Circulating Activated Protein C

Upon activation, neutrophils release their content through different mechanisms like degranulation and NETosis, thus prompting thrombosis. The natural anticoagulant activated protein C (APC) inhibits neutrophil NETosis and, consequently, this may lower the levels of neutrophil activation markers in plasma, further diminishing the thrombotic risk exerted by this anticoagulant. We aimed to describe the status of markers of neutrophil activation in plasma of patients with venous thrombosis, their association with the thrombotic risk and the potential contribution of APC. We quantified three markers of neutrophil activation (cell-free DNA, calprotectin, and myeloperoxidase) in 253 patients with venous thromboembolism (VTE) in a stable phase (192 lower extremity VTE and 61 splanchnic vein thrombosis) and in 249 healthy controls. In them, we also quantified plasma APC, soluble endothelial protein C receptor (EPCR), and soluble thrombomodulin (TM), and we genotyped two genetic regulators of APC: the EPCR gene (PROCR) haplotypes (H) and the TM gene (THBD) c.1418C>T polymorphism. We found a significant increase in plasma cell-free DNA (p < 0.0001), calprotectin (p = 0.0001) and myeloperoxidase (p = 0.005) in VTE patients compared to controls. Furthermore, all three neutrophil activation markers were associated with an increase in the thrombotic risk. Cell-free DNA and calprotectin plasma levels were significantly correlated (Spearman r = 0.28; p < 0.0001). As expected, the natural anticoagulant APC was significantly decreased in VTE patients (p < 0.0001) compared to controls, what was mediated by its genetic regulators PROCR-H1, PROCR-H3, and THBD-c.1418T, and inversely correlated with cell-free DNA levels. This is the largest case-control study that demonstrates the increase in markers of neutrophil activation in vivo in VTE patients and their association with an increased thrombotic risk. This increase could be mediated by low APC levels and its genetic regulators, which could also increase NETosis, further enhancing thrombosis and inflammation.

Correlation between fecal calprotectin, ulcerative colitis endoscopic index of severity and clinical outcome in patients with acute severe colitis

Correlation between fecal calprotectin (FC) and endoscopic activity assessed by Ulcerative Colitis Endoscopic Index of Severity (UCEIS) in acute severe colitis (ASC) patients was explored to evaluate the predictive value of FC in clinical outcomes. Seventy-one ASC patients were retrospectively evaluated. FC level within 3 days of colonoscopy was measured with ELISA. Demographic and clinical data, laboratory parameters, and medical therapy were documented, and the endoscopic severity of disease was rated by UCEIS. The end points were the rate of failed corticosteroid therapy, colectomy, and mortality. There was significant correlation between UCEIS and FC level (r=0.729, P<0.001), which was superior to CRP, ESR, and hemoglobin. FC level between endoscopic mild activity (UCEIS, 3-4) and endoscopic moderate activity (UCEIS, 5-6), and endoscopic moderate activity (UCEIS, 5-6) and endoscopic severe activity (UCEIS, 7-8) were significantly different. FC levels were associated with different outcomes (failed corticosteroid therapy or surgery); when FC >1672 µg/g, sensitivity and specificity were 80.2 and 66.7%, respectively, in prediction for colectomy using receiver operating characteristics analysis. The results indicated that FC, as a non-invasive indicator, correlates positively with the UCEIS. Baseline FC level predicts clinical outcomes in ASC patients, which make a timely treatment strategy conversion possible after accurately forecasting the likelihood of failure of intravenous steroid therapy.

MicroRNAs and Neutrophil Activation Markers Predict Venous Thrombosis in Pancreatic Ductal Adenocarcinoma and Distal Extrahepatic Cholangiocarcinoma

Cancer-associated venous thrombosis (VTE) increases mortality and morbidity. However, limited tools are available to identify high risk patients. Upon activation, neutrophils release their content through different mechanisms, thereby prompting thrombosis. We explored plasma microRNAs (miRNAs) and neutrophil activation markers to predict VTE in pancreatic ductal adenocarcinoma (PDAC) and distal extrahepatic cholangiocarcinoma (DECC). Twenty-six PDAC and 6 DECC patients recruited at cancer diagnosis, were examined for deep vein thrombosis and pulmonary embolisms, and were then followed-up with clinical examinations, blood collections, and biCUS. Ten patients developed VTE and were compared with 22 age- and sex-matched controls. miRNA expression levels were measured at diagnosis and right before VTE, and neutrophil activation markers (cell-free DNA, nucleosomes, calprotectin, and myeloperoxidase) were measured in every sample obtained during follow-up. We obtained a profile of 7 miRNAs able to estimate the risk of future VTE at diagnosis (AUC = 0.95; 95% Confidence Interval (CI) (0.987, 1)) with targets involved in the pancreatic cancer and complement and coagulation cascades pathways. Seven miRNAs were up- or down-regulated before VTE compared with diagnosis. We obtained a predictive model of VTE with calprotectin as predictor (AUC = 0.77; 95% CI (0.57, 0.95)). This is the first study that addresses the ability of plasma miRNAs and neutrophil activation markers to predict VTE in PDAC and DECC.

Serum Procalcitonin as a Potential Early Predictor of Short-Term Outcomes in Acute Severe Ulcerative Colitis

BACKGROUND

Delayed colectomy can be life-threatening for patients with acute severe ulcerative colitis (ASUC). However, few biomarkers can predict the outcomes of ASUC patients before treatment. Serum procalcitonin (PCT) has been observed to be increased in ASUC patients.

AIM

The aim of this study was to estimate the association between serum PCT and short-term outcomes in patients with ASUC.

METHODS

A single-center observational study was conducted at a referral hospital from January 2012 to January 2018. Hospitalized ASUC patients, who were administered intravenous corticosteroids (IVCS), were enrolled and followed up for 6 months. The primary outcome was IVCS failure; the secondary outcome was colectomy. Relationships between indicators and clinical outcomes were assessed.

RESULTS

Of 152 ASUC patients enrolled in this study, 81 responded to IVCS and 71 failed (62 required short-term colectomy and 9 responded to second-line rescue therapy). Serum PCT on admission was significantly higher in IVCS-failure cases and surgical cases than in medical responders. Serum PCT ≥ 0.10 µg/L (OR = 4.134, p = 0.001) predicted IVCS failure with specificity of 0.741, and the combined measurement with fecal calprotectin (FC) ≥ 1500 µg/g improved the sensitivity. Serum PCT correlated significantly with the Ulcerative Colitis Endoscopic Index of Severity (r = 0.416, p < 0.001) and FC (r = 0.384, p < 0.001).

CONCLUSION

Serum PCT on admission could be a potential early non-invasive predictive biomarker for IVCS failure in ASUC patients, and a combination of PCT and FC could improve the predictive value.

HNL (Human Neutrophil Lipocalin) and a multimarker approach to the distinction between bacterial and viral infections

OBJECTIVES

The distinction between bacterial and viral causes of acute infections is a major clinical challenge. In this report we investigate the diagnostic performance in this regard of nine candidate biomarkers together with HNL (Human Neutrophil Lipocalin).

METHODS

Blood was obtained from patients with symptoms of infectious (n = 581). HNL was measured in whole blood (B-HNL) after pre-activation with the neutrophil activator fMLP or in plasma (P-HNL). Azurocidin also known as heparin-binding protein (HBP), Calprotectin, PMN-CD64, CRP (C-reactive protein), IP-10 (Interferon γ-induced Protein 10 kDa), PCT (Procalcitonin), TK1 (Thymidine kinase 1), TRAIL (TNF-related apoptosis-inducing ligand) were measured in plasma/serum. Area under the ROC (receiver operating characteristics) curve (AuROC) was used for the evaluation of the clinical performance of the biomarkers.

RESULTS

Side-by-side comparisons of the ten biomarkers showed large difference in the AuROC with B-HNL being the superior biomarker (0.91, 95% CI 0.86-0.95) and with the other nine biomarkers varying from AuROC of 0.63-0.79. The combination of B-HNL with IP-10 and/or TRAIL increased the diagnostic performance further to AuROCs of 0.94-0.97. The AuROCs of the combination of CRP with IP-10 and/or TRAIL were significantly lower than combinations with B-HNL 0.87 (95% CI 0.83-0.91).

CONCLUSION

The diagnostic performance of whole blood activated HNL was superior in the distinction between bacterial or viral infections. The addition of IP-10 and/or TRAIL to the diagnostic algorithm increased the performance of B-HNL further. The rapid analysis of HNL, reflecting bacterial infections, together with biomarkers reflecting viral infections may be the ideal combination of diagnostic biomarkers of acute infections.

Consecutive fecal calprotectin measurements for predicting relapse in pediatric Crohn’s disease patients

BACKGROUND

Asymptomatic children with Crohn’s disease (CD) require ongoing monitoring to ensure early recognition of a disease exacerbation.

AIM

In a cohort of pediatric CD patients, we aimed to assess the utility of serial fecal calprotectin measurements to detect intestinal inflammatory activity and predict disease relapse.

METHODS

In this prospective longitudinal cohort study, children with CD on infliximab therapy in clinical remission were included. Fecal calprotectin levels were assessed at baseline and at subsequent 2-5 visits. Clinical and biochemical disease activity were assessed using the Pediatric Crohn’s Disease Activity Index, C-reactive protein and erythrocyte sedimentation rate at baseline and at visits over the following 18 mo.

RESULTS

53 children were included and eighteen patients (34%) had a clinical disease relapse during the study. Baseline fecal calprotectin levels were higher in patients that developed symptomatic relapse [median (interquartile range), relapse 723 μg/g (283-1758) vs 244 μg/g (61-627), P = 0.02]. Fecal calprotectin levels > 250 μg/g demonstrated good predictive accuracy of a clinical flare within 3 mo (area under the receiver operator curve was 0.86, 95% confidence limits 0.781 to 0.937).

CONCLUSION

Routine fecal calprotectin testing in children with CD in clinical remission is useful to predict relapse. Levels > 250 μg/g are a good predictor of relapse in the following 3 mo. This information is important to guide monitoring standards used in this population.

Potential of Fecal Calprotectin as an Objective Marker to Discriminate Hospitalized Patients with Acute Severe Colitis from Outpatients with Less Severe Disease

BACKGROUND

Acute severe colitis (ASC) is conventionally diagnosed by Truelove and Witts' criteria which are non-specific and can be affected by other pathologic conditions. Fecal calprotectin (FCP) is a gut-specific marker of inflammation which can predict short-term outcomes in patients with ASC. We aimed to define the role of FCP in the diagnosis of ASC.

METHODS

This prospective observational cohort study included adult patients (> 18 years) with ulcerative colitis (UC) for whom FCP was measured and was under follow-up from April 2015 to December 2016. Patients were divided into two cohorts: (1) all consecutive hospitalized patients with ASC as defined by Truelove and Witts' criteria; (2) outpatients with active UC (defined by Mayo score) who did not fulfill Truelove and Witts' criteria. FCP levels were compared between the two cohorts, and a cutoff for FCP to diagnose ASC was determined.

RESULTS

Of 97 patients, 49 were diagnosed with ASC (mean age: 36.1 ± 11.9 years, 36 males) and 48 with active UC (mean age: 37.9 ± 12.4 years, 25 males). Median FCP levels were significantly higher in patients with ASC [1776(952-3123) vs 282(43-568) µg/g, p < 0.001] than mild to moderately active UC (n = 48) or moderately active UC [n = 35, 1776(952-3123) vs 332(106-700) µg/g, p < 0.001]. A FCP cutoff of 782 μg/g of stool had excellent diagnostic accuracy, with an area under the curve of 0.92(95% CI 0.87-0.97), sensitivity of 84% and specificity of 88% to differentiate ASC from active UC.

CONCLUSION

FCP could differentiate ASC from mild to moderate patients with UC, but requires validation before clinical use.

The importance of calprotectin for differentiating organic inflammatory disease and avoiding unnecessary procedures in paediatrics

BACKGROUND AND OBJECTIVE

The objective of the study was to determine the ability of faecal calprotectin to differentiate functional and organic intestinal diseases in paediatric patients, and to evaluate the correlation between inflammatory parameters and levels of faecal calprotectin.

PATIENTS AND METHODS

This retrospective study involved clinical data from 129 paediatric patients with symptoms of intestinal pathology. Faecal calprotectin was determined by quantitative immunoassay. Patients were classified into three groups: functional (32.8% of patients); organic non-inflammatory bowel disease (IBD, 53.9%); and organic IBD (13.3%).

RESULTS

Calprotectin levels were significantly different among the three groups; between patients with IBD and the others, and also between patients with non-organic IBD and functional. Positive associations were found between high levels of calprotectin and higher erythrocyte sedimentation rate (rho=0.497), C-reactive protein (rho=0.460), and platelet count (rho=0.232). Nevertheless, an inverse correlation was found between high levels of calprotectin and transferrin saturation (rho=-0.310), albumin (rho=-0.412), and haemoglobin levels (rho=-0.309).

DISCUSSION

Determination of faecal calprotectin is a complementary tool in clinical practice for discriminating between functional and organic IBD, avoiding, according to the levels of calprotectin, unnecessary invasive procedures in paediatric patients.

Fecal Calprotectin Test Performed at Home: A Prospective Study of Pediatric Patients With Inflammatory Bowel Disease

OBJECTIVES

Measuring fecal calprotectin (FC) in a laboratory is time-consuming and that is why home tests have been developed. We studied the use of an FC home test in pediatric patients with inflammatory bowel disease (PIBD) in real-life settings.

METHODS

The patients were asked to perform the IBDoc FC home test monthly for 6 months and to report their clinical disease activity at testing. Clinical decision-making, however, was guided by routine FC enzyme-linked immunosorbent assay (ELISA) for patients with raised IBDoc values. Spare frozen samples were analyzed using ELISA and IBDoc in the laboratory. The participants completed a questionnaire about FC testing at the start and end of the study.

RESULTS

Of the 52 patients, 35 (67%) ages 5 to 18 years completed the study, and 197 home tests were performed. Of these, 15% failed, mainly because of technical reasons. Just under half of the patients (47%) considered home testing comparable or superior to routine testing. In contrast, the parents were unsatisfied (61%), mostly because the IBDoc results were significantly different from ELISA and they found the phone application difficult to handle but whenever the IBDoc was performed by a laboratory professional it was comparable with ELISA, suggesting that practical issues hampered home testing. Despite their reservations, more than 80% of parents felt that home testing would improve disease management.

CONCLUSIONS

PIBD patients and their families were interested in FC home monitoring and willing to adopt testing as a part of their disease management, but this approach requires thorough guidance.

Faecal Calprotectin and UCEIS Predict Short-term Outcomes in Acute Severe Colitis: Prospective Cohort Study

BACKGROUND AND AIMS

Early objective markers for failure of intravenous[iv] corticosteroid for acute severe colitis [ASC] can avoid delay in rescue therapy or colectomy. We investigated faecal calprotectin [FC], C-reactive protein [CRP], and endoscopy using the ulcerative colitis endoscopic index of severity [UCEIS] as predictors of steroid failure following intensive therapy of ASC.

METHODS

Consecutive patients with ASC satisfying Truelove and Witts' criteria, hospitalised at a single centre from May 2015 to November 2016, were included; all received iv corticosteroids. The primary outcome measure was steroid failure defined as colectomy and/or rescue therapy with ciclosporin or infliximab during admission. FC levels were measured at admission and on Day 3 of intensive therapy. UCEIS was scored at admission, and CRP on Day 3 of intensive therapy.

RESULTS

Of 49 patients, 21 [43%] failed iv corticosteroids and 15 [31%] underwent surgery. FC levels were significantly higher in steroid failures (2522 [590-9654] µg/g) compared with steroid responders (1530 [352-10278] µg/g) at admission [p = 0.04], as well as on Day 3 of iv corticosteroid therapy (2718 [222-9175] µg/g vs 727 [218-4062] µg/g, p = 0.001). Steroid failures had a higher median [range] UCEIS score than responders (6 [4-8] vs 5 [4-7] [p = 0.001]). CRP level did not differ significantly between steroid failures and responders. A UCEIS > 6 at admission and FC > 1000 µg/g on Day 3 were independent predictors of steroid failure and need for rescue therapy/colectomy.

CONCLUSIONS

All patients with UCEIS > 6 and Day 3 FC > 1000 µg/g failed iv corticosteroids. The UCEIS score on admission and Day 3 FC are early predictors of failure of ivcorticosteroid therapy.

Parallel Changes in Harvey-Bradshaw Index, TNFα, and Intestinal Fatty Acid Binding Protein in Response to Infliximab in Crohn's Disease

Intestinal fatty acid binding protein (I-FABP) indicates barrier integrity.

AIMS

determine if I-FABP is elevated in active Crohn's disease (CD) and if I-FABP parallels anti-TNFα antibody (infliximab) induced lowering of TNFα and Harvey-Bradshaw Index (HBI) as potential indicator of mucosal healing. I-FABP distribution along human gut was determined. Serum from 10 CD patients collected during first three consecutive infliximab treatments with matched pretreatment and follow-up samples one week after each treatment and corresponding HBI data were analyzed. I-FABP reference interval was established from 31 healthy subjects with normal gut permeability. I-FABP and TNFα were measured by ELISA; CRP was measured by nephelometry. Healthy tissue was used for I-FABP immunohistochemistry. Pretreatment CD patient TNFα was 1.6-fold higher than in-house reference interval, while I-FABP was 2.5-fold higher, which lowered at follow-ups. Combining all 30 infusion/follow-up pairs also revealed changes in I-FABP. HBI followed this pattern; CRP declined gradually. I-FABP was expressed in epithelium of stomach, jejunum, ileum, and colon, with the highest expression in jejunum and ileum. I-FABP is elevated in active CD with a magnitude comparable to TNFα. Parallel infliximab effects on TNFα, HBI, and I-FABP were found. I-FABP may be useful as an intestine selective prognostic marker in CD.

The comparison of acute high-intensity interval exercise vs. continuous moderate-intensity exercise on plasma calprotectin and associated inflammatory mediators

PURPOSE

Calprotectin promotes the release of inflammatory mediators (e.g., monocyte chemoattractant protein-1 [MCP-1] and myeloperoxidase [MPO]) during the innate immune response as a mechanism to augment leukocyte chemotaxis and phagocytosis. Although plasma calprotectin is elevated with traditional continuous moderate-intensity exercise (CME) as an indicator of the inflammatory response, high-intensity interval exercise (HIIE) has been shown to attenuate systemic inflammation while providing similar improvements in cardiovascular health. Therefore, the purpose of this study was to compare plasma levels of calprotectin, MCP-1, and MPO between acute HIIE vs. CME.

METHODS

Nine healthy males (24.67±3.27yrs) were recruited to participate in HIIE and CME on a cycle ergometer. HIIE consisted of 10 repeated 60s of cycling at 90% max watts (W_max) separated by 2min of active recovery intensity of interval exercise, whereas CME consisted of 28min of cycling at 60% W_max. Blood samples were collected prior to, immediately post, and 30 and 60min into recovery following exercise.

RESULTS

Acute HIIE elicited a lower elevation in calprotectin and MPO compared to CME. An increase in MCP-1 was observed across time in both exercise protocols. Furthermore, our analyses did not reveal any significant correlation in percent change (baseline to immediately following exercise) among calprotectin, MCP1, and MPO in neither HIIE nor CME. However, a significant positive correlation was observed in the overall release of calprotectin and MPO across all four time points in both HIIE and CME. Conclusions Our findings indicate that acute HIIE may potentially diminish the systemic release of inflammatory mediators (calprotectin and MPO) compared to CME.

From clinical uncertainties to precision medicine: the emerging role of the gut barrier and microbiome in small bowel functional diseases

Over the last decade, remarkable progress has been made in the understanding of disease pathophysiology. Many new theories expound on the importance of emerging factors such as microbiome influences, genomics/omics, stem cells, innate intestinal immunity or mucosal barrier complexities. This has introduced a further dimension of uncertainty into clinical decision-making, but equally, may shed some light on less well-understood and difficult to manage conditions. Areas covered: Comprehensive review of the literature on gut barrier and microbiome relevant to small bowel pathology. A PubMed/Medline search from 1990 to April 2017 was undertaken and papers from this range were included. Expert commentary: The scenario of clinical uncertainty is well-illustrated by functional gastrointestinal disorders (FGIDs). The movement towards achieving a better understanding of FGIDs is expressed in the Rome IV guidelines. Novel diagnostic and therapeutic protocols focused on the GB and SB microbiome can facilitate diagnosis, management and improve our understanding of the underlying pathological mechanisms in FGIDs.

Fecal calprotectin as an alternative to ulcerative colitis endoscopic index of severity to predict the response to corticosteroids of acute severe ulcerative colitis: A prospective observational study

BACKGROUND

Fecal calprotectin (FC) might be an alternative to ulcerative colitis endoscopic index of severity (UCEIS) to predict the response to corticosteroids (CS) in acute severe colitis (ASC).

METHODS

One hundred and seventeen ASC patients were prospectively enrolled. Demographic, clinical, laboratory and sigmoidoscopic data were documented. Multivariate and ROC analyses were performed to identify risk factors for non-response to CS, and the predictive accuracy of possible predictors was assessed.

RESULTS

Totally, 39 (33.33%) patients failed intravenous CS therapy. CS responders among mild (UCEIS 3-4), moderate (UCEIS 5-6) and severe (UCEIS 7-8) groups were 40/44 (90.91%) vs. 36/55 (65.45%) vs. 2/18 (11.11%) (p<0.001). UCEIS (OR=5.08; 95% CI, 1.93-8.66; p<0.001) and FC (OR=2.56; 95% CI, 1.17-3.55; p=0.022) were found to be independent risk factors for CS non-responders. Compared with C-reactive protein, platelet, hemoglobin and albumin, baseline FC had the strongest correlation with UCEIS (r=0.701, p<0.001). ROC analysis of UCEIS and baseline FC in predicting CS non-response showed an AUC of 0.85 and 0.76 respectively.

CONCLUSIONS

Baseline FC levels correlated significantly with UCEIS in ASC, and both were useful in predicting short-term outcome of CS treatment. Baseline FC levels could be used as an alternative of UCEIS to guide the decision of early salvage therapy or colectomy and reduce the adverse effects of long-term futile CS usage.

A prospective study of fecal calprotectin and lactoferrin as predictors of small bowel Crohn's disease in patients undergoing capsule endoscopy

BACKGROUND

Capsule endoscopy (CE) is often used to investigate small bowel Crohn's disease (CD).

AIM

The aim of this study is to prospectively assess the value of fecal calprotectin and lactoferrin to predict CE findings.

PATIENTS AND METHODS

Sixty-eight consecutive patients that were referred for CE were included. Stool samples for calprotectin and lactoferrin and blood samples were collected for relevant parameters. Correlation between fecal markers and CE findings was assessed and receiver operating characteristic (ROC) curves were built to determine the predictive values of fecal markers for the diagnosis of CD.

RESULTS

Fecal calprotectin data was available for all the patients and lactoferrin data for 38. CE findings compatible with CD were found in 23 (33%) patients and 45 (67%) were negative for CD. The average age of the CD group was 34 compared to 46 in the non-CD group (p = .048). Median calprotectin and lactoferrin in the CD group and in the control group were 169 mg/kg vs. 40 (p = .004) and 6.6 mg/kg vs. 1 (p = .051), respectively. The area under the ROC curve was 0.767 for calprotectin and 0.70 for lactoferrin. A fecal calprotectin concentration of 95 mg/kg and fecal lactoferrin of 1.05 mg/kg had a sensitivity, specificity, positive predictive value and negative predictive value of 77 and 73%, 60 and 65%, 50 and 50%, and 84 and 84% in predicting CE findings compatible with CD.

CONCLUSIONS

Fecal markers are simple and noninvasive surrogates for predicting CE findings compatible with CD. Fecal markers can help determine which patients should be referred for CE. ClinicalTrials.gov Identifier: NCT01266629.

Hornerin Is Involved in Breast Cancer Progression

Purpose

The S100 gene family, which comprises over 20 members, including S100A1, S100A2, S100A8, S100A9, profilaggrin, and hornerin encodes low molecular weight calcium-binding proteins with physiological and pathological roles in keratinization. Recent studies have suggested a link between S100 proteins and human cancer progression. The purpose of the present study was to determine the expression levels of hornerin, S100A8, and S100A9 and evaluate their roles in the progression of invasive ductal carcinoma (IDC).

Methods

Seventy cases of ductal carcinoma in situ (DCIS), IDC, and metastatic carcinoma in lymph nodes (MCN) were included. Tissue microarrays were constructed from lesions of DCIS, IDC, and MCN from the same patients. Expression of hornerin, S100A8, and S100A9 was analyzed using immunohistochemistry.

Results

The expression of hornerin was associated with the estrogen receptor-negative (p=0.003) and the human epidermal growth factor receptor 2-positive (p=0.002) groups. The expression of S100A8 was associated with a higher pT stage (p=0.017). A significant (p<0.001) correlation between the expression of S100A9 and S100A8 was also found. The mean percentages of hornerin-positive tumor cells in DCIS, IDC, and MCN were 1.0%±3.3% (mean±standard deviation), 12.0%±24.0%, and 75.3%± 27.6%, respectively. The expression of hornerin significantly (p<0.001) increased with the progression of carcinoma. The mean levels of S100A8 and S100A9 in DCIS, IDC, and MCN were not significantly (p>0.050) different. The expression of hornerin increased in a stepwise manner (DCIS<IDC<MCN).

Conclusion

Our data suggest that hornerin is involved in breast cancer progression and malignant transformation from preinvasive lesions.

Comparative Analysis of Calcium-Binding Myeloid-Related Protein-8/14 in Saliva and Serum of Patients With Periodontitis and Healthy Individuals

BACKGROUND

This study aims to investigate calcium-binding myeloid-related protein (MRP)-8/14 in the saliva and serum of individuals with periodontitis and periodontally healthy individuals for the assessment of its role in the pathogenesis and clinical diagnosis of periodontitis.

METHODS

This cross-sectional study includes 56 patients with periodontitis and 44 periodontally healthy individuals. Saliva and serum were collected for the detection of MRP-8/14 and calcium levels. Periodontopathic bacteria were determined by polymerase chain reaction in saliva. Correlations between salivary and serum MRP-8/14 levels and clinical parameters, bacteria, and calcium were analyzed with Pearson correlation in a multiple regression model. MRP-8/14 levels were documented with receiver operating characteristic (ROC) curves.

RESULTS

Compared with healthy individuals, MRP-8/14 levels were significantly higher in both the saliva and serum of patients with periodontitis, but calcium was increased only in saliva. A high diagnostic potential of salivary MRP-8/14 was detected for periodontitis (ROC = 0.86). Salivary MRP-8/14 levels correlated significantly with the presence of the periodontopathogen Treponema denticola, as well as with the clinical parameters of periodontitis.

CONCLUSION

MRP-8/14 in saliva might be a potential diagnostic parameter for periodontal disease.

Association of calprotectin with leukocyte chemotactic and inflammatory mediators following acute aerobic exercise

The objective of this study was to examine whether acute aerobic exercise-mediated calprotectin in plasma would be associated with monocyte chemotactic protein-1 (MCP-1), myeloperoxidase (MPO), and interleukin-6 (IL-6) in healthy individuals. Eleven healthy participants, aged 18 to 30 years, were recruited to perform a 30-min bout of aerobic exercise at 75% maximal oxygen uptake. Acute aerobic exercise elicited a significant elevation across time in plasma calprotectin, MCP-1, MPO, and IL-6. Body mass index (BMI) was positively correlated with calprotectin area-under-the-curve with "respect to increase" (AUCi) and IL-6 AUCi. Furthermore, calprotectin AUCi was positively correlated with IL-6 AUCi and MPO AUCi, even after controlling for BMI. Although MPO AUCi was positively correlated with IL-6 AUCi, this relationship no longer existed after controlling for BMI. These results suggest that acute aerobic exercise could mediate innate immune response associated with calprotectin and its related leukocyte chemotactic and inflammatory mediators, especially in individuals with elevated BMI.

Red blood cell transfusions increase fecal calprotectin levels in premature infants

OBJECTIVE

We hypothesized that red blood cell (RBC) transfusions influence intestinal inflammation in very low birth weight (VLBW) infants. We also suspected that hematocrit (Hct) at transfusions and RBC storage time correlate with intestinal inflammation.

STUDY DESIGN

VLBW infants, without major congenital defects, intestinal perforation or necrotizing enterocolitis, were enrolled prospectively. Fecal calprotectin (FC) levels were measured from stool samples collected before and after RBC transfusions. Data on Hct and RBC storage time were collected.

RESULT

Data from 42 RBC transfusions given to 26 infants revealed that FC levels increased faster than baseline after RBC transfusions (P=0.018) and were higher in multiple-transfused infants (0 to 48 and >48 h post transfusion, P=0.007 and P=0.005, respectively). Lower Hct and RBC storage >21 days correlated with higher FC levels (P=0.044 and P=0.013, respectively).

CONCLUSION

RBC transfusions, anemia and prolonged RBC storage were associated with an increase in intestinal inflammation.

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.

Serum Calprotectin: A Potential Biomarker for Neonatal Sepsis

INTRODUCTION

The correct diagnosis of neonatal sepsis is a relevant problem because sepsis is one of the most important causes of neonatal morbidity, mortality, and prolonged hospital stay. Calprotectin is an antimicrobial, calcium and zinc binding heterocomplex protein that could be used as a nonspecific marker for activation of granulocytes and mononuclear phagocytes. Calprotectin has been proposed for the diagnosis of inflammatory conditions. Our aim is to study serum calprotectin as a biomarker for neonatal sepsis diagnosis.

METHODS

41 (20 females, 21 males) infants who underwent blood culture due to suspected sepsis were enrolled in the study. Serum calprotectin was measured by a commercial ELISA assay (Calprest, Eurospital, Trieste, Italy). Statistical analysis was performed using the statistical software package Stata 13.1 (Stata Corporation, College Station, Texas, USA).

RESULTS

8 neonates (19.51%) showed sepsis with positive culture and 33 (80.49%) showed suspected sepsis. The optimal cut-off for calprotectin is 2.2 μg/mL with a sensitivity of 62.5% and a specificity of 69.7%.

CONCLUSIONS

Calprotectin may be considered a promising early, sensitive, specific marker of sepsis thanks to the importance of calprotectin in defense mechanisms and physiological functions of the immune system.

Clinical significance of the glucose breath test in patients with inflammatory bowel disease

BACKGROUND AND AIM

Small intestinal bacterial overgrowth which has recently been diagnosed with the glucose breath test is characterized by excessive colonic bacteria in the small bowel, and results in gastrointestinal symptoms that mimic symptoms of inflammatory bowel disease. This study aimed to estimate the positivity of the glucose breath test and investigate its clinical role in inflammatory bowel disease.

METHODS

Patients aged > 18 years with inflammatory bowel disease were enrolled. All patients completed symptom questionnaires. Fecal calprotectin level was measured to evaluate the disease activity. Thirty historical healthy controls were used to determine normal glucose breath test values.

RESULTS

A total of 107 patients, 64 with ulcerative colitis and 43 with Crohn's disease, were included. Twenty-two patients (20.6%) were positive for the glucose breath test (30.2%, Crohn's disease; 14.1%, ulcerative colitis). Positive rate of the glucose breath test was significantly higher in patients with Crohn's disease than in healthy controls (30.2% vs 6.7%, P=0.014). Bloating, flatus, and satiety were higher in glucose breath test-positive patients than glucose breath test-negative patients (P=0.021, 0.014, and 0.049, respectively). The positivity was not correlated with the fecal calprotectin level.

CONCLUSIONS

The positive rate of the glucose breath test was higher in patients with inflammatory bowel disease, especially Crohn's disease than in healthy controls; gastrointestinal symptoms of patients with inflammatory bowel disease were correlated with this positivity. Glucose breath test can be used to manage intestinal symptoms of patients with inflammatory bowel disease.

Necrotizing enterocolitis: a clinical review on diagnostic biomarkers and the role of the intestinal microbiota

Necrotizing enterocolitis (NEC) remains one of the most frequent gastrointestinal diseases in the neonatal intensive care unit, with a continuing unacceptable high mortality and morbidity rates. Up to 20% to 40% of infants with NEC will need surgical intervention at some point. Although the exact pathophysiology is not yet elucidated, prematurity, use of formula feeding, and an altered intestinal microbiota are supposed to induce an inflammatory response of the immature intestine. The clinical picture of NEC has been well described. However, an early diagnosis and differentiation against sepsis is challenging. Besides, it is difficult to timely identify NEC cases that will deteriorate and need surgical intervention. This may interfere with the most optimal treatment of infants with NEC. In this review, we discuss the pathogenesis, diagnosis, and treatment of NEC with a focus on the role of microbiota in the development of NEC. An overview of different clinical prediction models and biomarkers is given. Some of these are promising tools for accurate diagnosis of NEC and selection of appropriate therapy.

The effect of bariatric surgery on intestinal absorption and transit time

BACKGROUND

Bariatric surgical procedures are classified by their presumed mechanisms of action: restrictive, malabsorptive or a combination of both. However, this dogma is questionable and remains unproven. We investigated post-operative changes in nutrient absorption and transit time following bariatric surgery.

METHODS

Participants were recruited into four groups: obese controls (body mass index (BMI) >30 kg/m2, n = 7), adjustable gastric banding (n = 6), Roux-en-Y gastric bypass (RYGB, n = 7) and biliopancreatic diversion with duodenal switch (DS, n = 5). Participants underwent sulphasalazine/sulphapyridine tests (oro-caecal transit time); fasting plasma citrulline (functional enterocyte mass); 3 days faecal collection for faecal elastase 1 (FE-1); calprotectin (FCp); faecal fatty acids (pancreatic exocrine function, gut inflammation and fat excretion, respectively); and 5 h D-xylose, L-rhamnose and lactulose test (intestinal absorption and permeability).

RESULTS

Age and gender were not different but BMI differed between groups (p = 0.001). No difference in oro-caecal transit time (p = 0.935) or functional enterocyte mass (p = 0.819) was detected. FCp was elevated post-RYGB vs. obese (p = 0.016) and FE-1 was reduced post-RYGB vs. obese (p = 0.002). Faecal fat concentrations were increased post-DS vs. obese (p = 0.038) and RYGB (p = 0.024) and were also higher post-RYGB vs. obese (p = 0.033). Urinary excretion of D-xylose and L-rhamnose was not different between the groups; however, lactulose/rhamnose ratio was elevated post-DS vs. other groups (all p < 0.02), suggesting increased intestinal permeability.

CONCLUSIONS

Following RYGB, there are surprisingly few abnormalities or indications of severe malabsorption of fats or sugars. Small bowel adaptation after bariatric surgery may be key to understanding the mechanisms responsible for the beneficial metabolic effects of these operations.

Breast-feeding improves gut maturation compared with formula feeding in preterm babies

OBJECTIVE

The incidence of necrotizing enterocolitis (NEC) is higher in formula-fed babies than in breast-fed babies, which may be caused by breast-feeding-induced gut maturation. The effect of breast-feeding on gut maturation has been widely studied in animal models. This study aimed to assess the effects of breast-feeding on intestinal maturation in prematurely born babies by evaluating postnatal changes in urinary intestinal fatty acid binding protein (I-FABP) levels, a specific enterocyte marker.

METHODS

Gut maturation in 40 premature babies (<37 weeks of gestation) without gastrointestinal morbidity was studied, of whom 21 were exclusively breast-fed and 19 were formula-fed infants. Urinary I-FABP levels as the measure of gut maturation were measured at 5, 12, 19, and 26 days after birth.

RESULTS

In breast-fed infants, there was a significant increase in median urinary I-FABP levels between 5 and 12 days after birth (104 [78-340] pg/mL to 408 [173-1028] pg/mL, P = 0.002), whereas I-FABP concentration in formula-fed infants increased between 12 and 19 days after birth (105 [44-557] pg/mL, 723 [103-1670] pg/mL, P = 0.004). Breast-fed babies had significantly higher median urinary I-FABP levels at postnatal day 12 (P = 0.01).

CONCLUSIONS

The time course of the postnatal increase in urinary I-FABP levels reflecting gut maturation was significantly delayed in formula-fed babies, suggesting a delayed physiological response in formula-fed compared with breast-fed infants.

Intestinal permeability--a new target for disease prevention and therapy

Data are accumulating that emphasize the important role of the intestinal barrier and intestinal permeability for health and disease. However, these terms are poorly defined, their assessment is a matter of debate, and their clinical significance is not clearly established. In the present review, current knowledge on mucosal barrier and its role in disease prevention and therapy is summarized. First, the relevant terms 'intestinal barrier' and 'intestinal permeability' are defined. Secondly, the key element of the intestinal barrier affecting permeability are described. This barrier represents a huge mucosal surface, where billions of bacteria face the largest immune system of our body. On the one hand, an intact intestinal barrier protects the human organism against invasion of microorganisms and toxins, on the other hand, this barrier must be open to absorb essential fluids and nutrients. Such opposing goals are achieved by a complex anatomical and functional structure the intestinal barrier consists of, the functional status of which is described by 'intestinal permeability'. Third, the regulation of intestinal permeability by diet and bacteria is depicted. In particular, potential barrier disruptors such as hypoperfusion of the gut, infections and toxins, but also selected over-dosed nutrients, drugs, and other lifestyle factors have to be considered. In the fourth part, the means to assess intestinal permeability are presented and critically discussed. The means vary enormously and probably assess different functional components of the barrier. The barrier assessments are further hindered by the natural variability of this functional entity depending on species and genes as well as on diet and other environmental factors. In the final part, we discuss selected diseases associated with increased intestinal permeability such as critically illness, inflammatory bowel diseases, celiac disease, food allergy, irritable bowel syndrome, and--more recently recognized--obesity and metabolic diseases. All these diseases are characterized by inflammation that might be triggered by the translocation of luminal components into the host. In summary, intestinal permeability, which is a feature of intestinal barrier function, is increasingly recognized as being of relevance for health and disease, and therefore, this topic warrants more attention.

Accurate prediction of anastomotic leakage after colorectal surgery using plasma markers for intestinal damage and inflammation

BACKGROUND

Anastomotic leakage is a frequent and life-threatening complication after colorectal surgery. Early recognition of anastomotic leakage is critical to reduce mortality. Because early clinical and radiologic signs of anastomotic leakage are often nonspecific, there is an urgent need for accurate biomarkers. Markers of inflammation and gut damage might be suitable, as these are hallmarks of anastomotic leakage.

STUDY DESIGN

In 84 patients undergoing scheduled colorectal surgery with primary anastomosis, plasma samples were collected preoperatively and daily after surgery. Inflammatory markers, C-reactive protein; calprotectin; and interleukin-6, and intestinal damage markers, intestinal fatty acid binding protein; liver fatty acid binding protein; and ileal bile acid binding protein, were measured. Diagnostic accuracy of single markers or combinations of markers was analyzed by receiver operating characteristic curve analysis.

RESULTS

Anastomotic leakage developed in 8 patients, clinically diagnosed at median day 6. Calprotectin had best diagnostic accuracy to detect anastomotic leakage postoperatively. Highest diagnostic accuracy was obtained when C-reactive protein and calprotectin were combined at postoperative day 3, yielding sensitivity of 100%, specificity of 89%, positive likelihood ratio = 9.09 (95% CI, 4.34-16), and negative likelihood ratio = 0.00 (95% CI, 0.00-0.89) (p < 0.001). Interestingly, preoperative intestinal fatty acid binding protein levels predicted anastomotic leakage at a cutoff level of 882 pg/mL with sensitivity of 50%, specificity of 100%, positive likelihood ratio = infinite (95% CI, 4.01-infinite), and negative likelihood ratio = 0.50 (95% CI, 0.26-0.98) (p < 0.0001).

CONCLUSIONS

Preoperative intestinal fatty acid binding protein measurement can be used for anastomotic leakage risk assessment. In addition, the combination of C-reactive protein and calprotectin has high diagnostic accuracy. Implementation of these markers in daily practice deserves additional investigation.

Quantitative gingival crevicular fluid proteome in health and periodontal disease using stable isotope chemistries and mass spectrometry

AIM

Application of quantitative stable isotope-labelling chemistries and mass spectrometry (MS) to determine alterations in gingival crevicular fluid (GCF) proteome in periodontal disease.

MATERIAL AND METHODS

Quantitative proteome of GCF from 40 healthy individuals versus 40 patients with periodontal disease was established using 320 GCF samples and stable isotope-labelling reagents, ICAT and mTRAQ, with MS technology and validated by enzyme-linked immunosorbent methods.

RESULTS

We have identified 238 distinct proteins of which 180 were quantified in GCF of both healthy and periodontal patients with additional 26 and 32 distinct proteins that were found only in GCF of healthy or periodontal patients. In addition, 42 pathogenic bacterial proteins and 11 yeast proteins were quantified. The data highlighted a series of proteins not quantified previously by large-scale MS approaches in GCF with relevance to periodontal disease, such as host-derived Ig alpha-2 chain C, Kallikrein-4, S100-A9, transmembrane proteinase 13, peptidase S1 domain, several collagen types and pathogenic bacterial proteins, e.g. formamidase, leucine aminopeptidase and virulence factor OMP85.

CONCLUSIONS

The innovative analytical approaches provided detailed novel changes in both host and microbial derived GCF proteomes of periodontal patients. The study defined 50 host and 16 pathogenic bacterial proteins significantly elevated in periodontal disease most of which were novel with significant potential for application in the clinical arena of periodontal disease.

Stool calprotectin in necrotizing enterocolitis

Background:

Calprotectin is a 36 kDa protein present in the cytoplasm of the neutrophil has antimicrobial and apoptosis inducing activities. In vitro studies have shown that calprotectin inhibits the growth of various microorganisms. Necrotizing enterocolitis (NEC) remains one of the leading causes of morbidity and mortality in neonatal intensive care units (NICU), affecting up to 5% of premature infants. Fecal calprotectin is resistant to degradation and has been proposed as a useful marker of gastrointestinal inflammation.

Objective:

The objective of the present study is to evaluate fecal calprotectin concentrations in NEC.

Study Design:

Fifteen neonates with a clinical diagnosis of NEC were studied; they admitted at NICU of Zagazig University Hospital. In addition, 20 age sex matched neonates fed all caloric requirement served as the control group. All neonates were subjected to history taking, clinical examination, laboratory investigations (complete blood count, C-reactive protein) and determination of stool calprotectin.

Results:

There was a highly significant increase in fecal calprotectin in patients than control and there was a highly significant increase in its fecal level in died patients than living one. Also significant increase in fecal calprotectin level with increasing severity of NEC.

Conclusion:

Fecal calprotectin measurements could be a valuable tool for the investigation of preterm and full term infants suspected of having NEC.

Non-invasive serum amyloid A (SAA) measurement and plasma platelets for accurate prediction of surgical intervention in severe necrotizing enterocolitis (NEC)

Objective

To evaluate the value of biomarkers to detect severe NEC.

Summary Background Data

The time point of surgery in necrotizing enterocolitis (NEC) is critical. Therefore, there is a need for markers that detect severe NEC, because clinical signs of severe NEC often develop late. This study evaluated the value of biomarkers reflecting intestinal cell damage and inflammation to detect severe NEC.

Methods

29 neonates with NEC were included. Two definitions of moderate versus severe NEC were analyzed: medical NEC (n = 12) versus surgical or fatal NEC (n = 17); and Bell stage II NEC (n = 13) versus stage III NEC (n = 16). Urinary intestinal fatty acid binding protein (I-FABP), serum amyloid A (SAA), C3a and C5a, and fecal calprotectin were measured. C-reactive protein (CRP), white blood cell count (WBC) and platelet count data were measured in blood.

Results

In both definitions of moderate versus severe NEC, urinary SAA levels were significantly higher in severe NEC. A cut-off value of 34.4 ng/ml was found in surgical NEC versus medical NEC (sensitivity, 83%; specificity, 83%; LR+, 4.88 (95% CI, 1.37–17.0); LR−, 0.20 (95% CI, 0.07–0.60)) at diagnosis of NEC and at one day prior to surgery in neonates who were operated later on. Combination of urinary SAA and platelet count increased the accuracy, with a sensitivity, 94%; specificity, 83%; LR+, 5.53 (95% CI, 1.57–20.0); and LR−, 0.07 (95% CI, 0.01–0.48).

Conclusion

Urinary SAA is an accurate marker in differentiating severe NEC from moderate NEC; particularly if combined with serum platelet count.

Impact of diets with a high content of greaves-meal protein or carbohydrates on faecal characteristics, volatile fatty acids and faecal calprotectin concentrations in healthy dogs

Background

Research suggests that dietary composition influences gastrointestinal function and bacteria-derived metabolic products in the dog colon. We previously reported that dietary composition impacts upon the faecal microbiota of healthy dogs. This study aims at evaluating the dietary influences on bacteria-derived metabolic products associated with the changes in faecal microbiota that we had previously reported. We fed high-carbohydrate starch based (HCS), [crude protein: 194 g/kg, starch: 438 g/kg], high-protein greaves-meal (HPGM), [crude protein: 609 g/kg, starch: 54 g/kg] and dry commercial (DC), [crude protein: 264 g/kg, starch: 277 g/kg] diets, and studied their effects on the metabolism of the colonic microbiota and faecal calprotectin concentrations in five Beagle dogs, allocated according to the Graeco-Latin square design. Each dietary period lasted for three weeks and was crossed-over with washout periods. Food intake, body weight, and faecal consistency scores, dry matter, pH, ammonia, volatile fatty acids (VFAs), and faecal canine calprotectin concentrations were determined.

Results

Faecal ammonia concentrations decreased with the HCS diet. All dogs fed the HPGM diet developed diarrhoea, which led to differences in faecal consistency scores between the diets. Faecal pH was higher with the HPGM diet. Moreover, decreases in propionic and acetic acids coupled with increases in branched-chain fatty acids and valeric acid caused changes in faecal total VFAs in dogs on the HPGM diet. Faecal canine calprotectin concentration was higher with the HPGM diet and correlated positively with valeric acid concentration.

Conclusions

The HPGM diet led to diarrhoea in all dogs, and there were differences in faecal VFA profiles and faecal canine calprotectin concentrations.

Evaluation of the diagnostic accuracy of plasma markers for early diagnosis in patients suspected for acute appendicitis

OBJECTIVES

The main objective of this study was to evaluate the diagnostic accuracy of two novel biomarkers, calprotectin (CP) and serum amyloid A (SAA), along with the more traditional inflammatory markers C-reactive protein (CRP) and white blood cell count (WBC), in patients suspected of having acute appendicitis (AA). The secondary objective was to compare diagnostic accuracy of these biomarkers with a clinical scoring system and radiologic imaging.

METHODS

A total of 233 patients with suspected AA, presenting to the emergency department (ED) between January 2010 and September 2010, and 52 healthy individuals serving as controls, were included in the study. Blood was drawn and CP and SAA-1 concentrations were measured using enzyme-linked immunosorbent assay (ELISA). CRP and WBC concentrations were routinely measured and retrospectively abstracted from the electronic health record, together with physical examination findings and radiologic reports. The Alvarado score was calculated as a clinical scoring system for AA. Final diagnosis of AA was based on histopathologic examination. The Mann-Whitney U-test was used for between-group comparisons. Receiver operating characteristic (ROC) curves were used to measure the diagnostic accuracy for the tests and to determine the best cutoff points.

RESULTS

Seventy-seven of 233 patients (33%) had proven AA. Median plasma levels for CP and SAA-1 were significantly higher in patients with AA than in those with another final diagnosis (CP, 320.9 ng/mL vs. 212.9 ng/mL; SAA-1, 30 mg/mL vs. 0.6 mg/mL; p < 0.001). CRP and WBC were significantly higher in patients with AA as well. The Alvarado score was helpful at the extremes (<3 or >7). Ultrasound (US) had a sensitivity of 84% and a specificity of 94%. Computed tomography (CT) had a sensitivity of 100% and a specificity of 91%. The area under the ROC (95% confidence interval [CI]) was 0.67 (95% CI = 0.60 to 0.74) for CP, 0.76 (95% CI = 0.70 to 0.82) for SAA, 0.71 (95% CI = 0.64 to 0.78) for CRP, and 0.79 (95% CI = 0.73 to 0.85) for WBC. No cutoff points had high enough sensitivity and specificity to accurately diagnose AA. However, a high sensitivity of 97% was shown at 7.5 × 10(9) /L for WBC and 0.375 mg/mL for SAA.

CONCLUSIONS

CP, SAA-1, CRP, and WBC were significantly elevated in patients with AA. None had cutoff points that could accurately discriminate between AA and other pathology in patients with suspected AA. A WBC < 7.5 × 10(9) /L, with a low level of clinical suspicion for AA, can identify a subgroup of patients who may be sent home without further evaluation, but who should have available next-day follow-up.

Calprotectin Is a Useful Tool in Distinguishing Coexisting Irritable Bowel-Like Symptoms from That of Occult Inflammation among Inflammatory Bowel Disease Patients in Remission

Background and Aim. In the inflammatory bowel diseases (IBDs), many symptoms are similar to the functional disorder irritable bowel syndrome (IBS). A challenge is thus to distinguish symptoms of IBD from IBS. The aim of this study was to investigate the levels of calprotectin in IBS-positive IBD patients in remission. Methods. Remission was defined as a simple clinical colitis activity index (SCCAI) or simple crohn's disease activity index (SCDAI) score of less than three and less than four, respectively. The Rome II criteria were used to identify cases, and the calprotectin ELISA test was used to quantify calprotectin in stools. Results. The Rome II criteria were fulfilled in 24.6% of ulcerative colitis (UC) patients, while the comparable number for Crohn's disease (CD) was 21.4%. There was a tendency for elevated fecal calprotectin levels in IBS-positive patients, regardless of diagnosis. However, these differences were only significant in CD. Conclusions. Calprotectin levels are elevated in subgroups of IBD patients that are in remission and have coexisting IBS-like symptoms. This study underscores the clinical usefulness of a noninvasive marker to distinguish patients in need of intensified followup from those that do not need further workup.

Interleukin-6 induces S100A9 expression in colonic epithelial cells through STAT3 activation in experimental ulcerative colitis

Background

Intestinal epithelium is essential for maintaining normal intestinal homeostasis; its breakdown leads to chronic inflammatory pathologies, such as inflammatory bowel diseases (IBDs). Although high concentrations of S100A9 protein and interleukin-6 (IL-6) are found in patients with IBD, the expression mechanism of S100A9 in colonic epithelial cells (CECs) remains elusive. We investigated the role of IL-6 in S100A9 expression in CECs using a colitis model.

Methods

IL-6 and S100A9 expression, signal transducer and activator of transcription 3 (STAT3) phosphorylation, and infiltration of immune cells were analyzed in mice with dextran sulfate sodium (DSS)-induced colitis. The effects of soluble gp130-Fc protein (sgp130Fc) and S100A9 small interfering (si) RNA (si-S100A9) on DSS-induced colitis were evaluated. The molecular mechanism of S100A9 expression was investigated in an IL-6-treated Caco-2 cell line using chromatin immunoprecipitation assays.

Results

IL-6 concentrations increased significantly in the colon tissues of DSS-treated mice. sgp130Fc or si-S100A9 administration to DSS-treated mice reduced granulocyte infiltration in CECs and induced the down-regulation of S100A9 and colitis disease activity. Treatment with STAT3 inhibitors upon IL-6 stimulation in the Caco-2 cell line demonstrated that IL-6 mediated S100A9 expression through STAT3 activation. Moreover, we found that phospho-STAT3 binds directly to the S100A9 promoter. S100A9 may recruit immune cells into inflamed colon tissues.

Conclusions

Elevated S100A9 expression in CECs mediated by an IL-6/STAT3 signaling cascade may play an important role in the development of colitis.

Noninvasive measurement of fecal calprotectin and serum amyloid A combined with intestinal fatty acid-binding protein in necrotizing enterocolitis

BACKGROUND

Diagnosis of necrotizing enterocolitis (NEC), prevalent in premature infants, remains challenging. Enterocyte damage in NEC can be assessed by intestinal fatty acid-binding protein (I-FABP), with a sensitivity of 93% and a specificity of 90%. Numerous markers of inflammation are known, such as serum amyloid A (SAA) and fecal calprotectin.

PURPOSE

The aim of the present study was to evaluate which combination of noninvasive measurement of inflammatory markers and I-FABP improves the diagnostic accuracy in neonates suspected for NEC.

METHODS

In 62 neonates with clinical suspicion of NEC (29 with final diagnosis of NEC), urinary I-FABP, urinary SAA, and fecal calprotectin levels were determined quantitatively. Diagnostic accuracy was calculated for the combinations I-FABP-SAA and I-FABP-fecal calprotectin, using a multivariable logistic regression model.

RESULTS

The combination of SAA and I-FABP did not increase the diagnostic accuracy of I-FABP. However, the combination of fecal calprotectin and I-FABP improved accuracy significantly. The combination of urinary I-FABP and fecal calprotectin measurement produced a sensitivity of 94%, a specificity of 79%, a positive likelihood ratio of 4.48, and a negative likelihood ratio of 0.08.

CONCLUSION

The combination of noninvasive measurement of I-FABP and fecal calprotectin seems promising for diagnosing NEC at an early time point. Prospective analysis is required to confirm this finding and to evaluate better treatment strategies based on noninvasive measurement of I-FABP and calprotectin.