Value of fecal calprotectin in the evaluation of patients with abdominal discomfort: an observational study

Plasminogen Activator Inhibitor 1 Is a Novel Faecal Biomarker for Monitoring Disease Activity and Therapeutic Response in Inflammatory Bowel Diseases

BACKGROUND AND AIMS

Crohn's disease [CD] and ulcerative colitis [UC] require lifelong treatment and patient monitoring. Current biomarkers have several limitations; therefore, there is an unmet need to identify novel biomarkers in inflammatory bowel disease [IBD]. Previously, the role of plasminogen activator inhibitor 1 [PAI-1] was established in the pathogenesis of IBD and suggested as a potential biomarker. Therefore, we aimed to comprehensively analyse the selectivity of PAI-1 in IBD, its correlation with disease activity, and its potential to predict therapeutic response.

METHODS

Blood, colon biopsy, organoid cultures [OC], and faecal samples were used from active and inactive IBD patients and control subjects. Serpin E1 gene expressions and PAI-1 protein levels and localisation in serum, biopsy, and faecal samples were evaluated by qRT-PCR, ELISA, and immunostaining, respectively.

RESULTS

The study population comprised 132 IBD patients [56 CD and 76 UC] and 40 non-IBD patients. We demonstrated that the serum, mucosal, and faecal PAI-1 concentrations are elevated in IBD patients, showing clinical and endoscopic activity. In responders [decrease of eMayo ≥3 in UC; or SES-CD  50% in CD], the initial PAI-1 level decreased significantly upon successful therapy. OCs derived from active IBD patients produced higher concentrations of PAI-1 than the controls, suggesting that epithelial cells could be a source of PAI-1. Moreover, faecal PAI-1 selectively increases in active IBD but not in other organic gastrointestinal diseases.

CONCLUSIONS

The serum, mucosal, and faecal PAI-1 concentration correlates with disease activity and therapeutic response in IBD, suggesting that PAI-1 could be used as a novel, non-invasive, disease-specific, faecal biomarker in patient follow-up.

Diagnostic value of fecal calprotectin in primary care patients with gastrointestinal symptoms: A retrospective Swedish cohort study

Aims

To investigate the diagnostic accuracy of fecal calprotectin (FC) for inflammatory bowel disease (IBD) and organic gastrointestinal disease (OGID) in primary care. To examine the association with demographic factors, symptoms and concomitant medical therapy.

Methods

A retrospective analysis of data on all semiquantitative FC tests from individuals ≥18 years conducted in primary care in Östergötland County in 2010. A 5-year follow-up with inclusion of new gastrointestinal diagnoses.

Results

A total of 1293 eligible patients were included. IBD was found in 8.8% and other OGID in 30.8% of patients with positive FC. Positive FC was associated with diarrhea, age >60 years, duration <3 months, use of nonsteroidal anti-inflammatory drug (NSAID), and proton pump inhibitor (PPI). Predictors of IBD were positive FC, diarrhea, rectal bleeding, and male sex; predictors of OGID positive FC, age >35 years, abnormal clinical findings, and duration <3 months. FC yielded the highest sensitivity and negative predictive value compared with demographic factors, symptoms, and duration. Use of NSAID and PPI showed a marginal increase in the sensitivity, positive predictive value, and decrease in the specificity of FC. Within 5 years, 4.0% had a new gastrointestinal diagnosis among patients with positive FC (0.6% IBD).

Conclusions

FC reliably rules out IBD and contradicts the presence of other OGID in primary care patients. Positive FC test together with other predictors, such as diarrhea, rectal bleeding, short duration, or age >35 years, should encourage a prioritized investigation. Use of NSAID, PPI, and ASA may affect the diagnostic accuracy of FC for IBD and OGID.

Evaluating the Potential of Casein Glycomacropeptide in Adult Irritable Bowel Syndrome Management: A Pilot Study

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder that affects 10-15% of the global population and presents symptoms such as abdominal discomfort, bloating and altered bowel habits. IBS is believed to be influenced by gut microbiota alterations and low-grade inflammation. Bovine kappa-casein glycomacropeptide (GMP), a bioactive dairy-derived peptide, possesses anti-adhesive, prebiotic and immunomodulatory properties that could potentially benefit IBS patients. This pilot study investigated the effects of daily supplementation with 30 g of GMP for three weeks on gut health in five people with IBS. We assessed alterations in gut microbiota composition, fecal and blood inflammatory makers, and gut-related symptoms before, during and after the GMP feeding period. The results revealed no changes in fecal microbiota, subtle effects on systemic and intestinal immune makers, and no changes in gut-related symptoms during and after the GMP supplementation. Further research is needed to assess the potential benefits of GMP in IBS patients, including the examination of dosage and form of GMP supplementation.

Changes in Calprotectin (S100A8-A9) and Aldolase in the Saliva of Horses with Equine Gastric Ulcer Syndrome

Equine gastric ulcer syndrome (EGUS) is a highly prevalent disease that affects horses worldwide. Within EGUS, two different forms have been described: equine squamous gastric disease (ESGD) and equine glandular gastric disease (EGGD). The associated clinical signs cause detrimental activity performance, reducing the quality of life of animals. Saliva can contain biomarkers for EGUS that could be potentially used as a complementary tool for diagnosis. The objective of this work was to evaluate the measurements of calprotectin (CALP) and aldolase in the saliva of horses as potential biomarkers of EGUS. For this purpose, automated assays for the quantification of these two proteins were analytically validated and applied for detecting EGUS in a total of 131 horses divided into 5 groups: healthy horses, ESGD, EGGD, combined ESGD and EGGD, and horses with other intestinal pathologies. The assays showed good precision and accuracy in analytical validation, and they were able to discriminate between horses with EGUS and healthy horses, especially in the case of CALP, although they did not show significant differences between horses with EGUS and horses with other diseases. In conclusion, salivary CALP and aldolase can be determined in the saliva of horses and further studies are warranted to elucidate the potential of these analytes as biomarkers in EGUS.

Elevated fecal levels of the inflammatory biomarker calprotectin in early systemic sclerosis

Knowledge on gastrointestinal manifestations in early systemic sclerosis (SSc) is limited. We have investigated gastrointestinal inflammation in SSc at the time of diagnosis using the inflammatory biomarker Fecal calprotectin (F-cal). Consecutive patients with suspected SSc were characterized in relation to the 2013 classification criteria for SSc and classified as SSc or SSc-like disease. F-cal levels were measured with a polyclonal ELISA (Calpro A/S, Lysaker, Norway) and levels above 50 µg/g were considered elevated. F-cal levels were compared to those of control subjects without rheumatic disease. Of 137 patients with suspected SSc, 92 were classified as SSc and 45 as SSc-like disease. Median (interquartile range) disease duration among the SSc participants was 2.5 (1.2, 4.6) years. A substantial proportion of participants classified as SSc (35/92, 38%) and SSc-like disease (14/45, 31%) exhibited elevated F-cal compared to the control group (3/41, 7.3%; p < 0.001 and p = 0.007, respectively). Elevated F-cal was associated with proton pump inhibitor usage (OR 7.14; 95% CI 2.56-29.93; p < 0.001). We conclude that elevated F-cal is present in a subgroup of patients with SSc at the time of diagnosis, suggesting that that GI inflammation may be present in this patient group early in the disease course. F-cal did not exhibit potential to differentiate SSc from SSc-like disease.

Impact of Biometric Patient Data, Probiotic Supplementation, and Selected Gut Microorganisms on Calprotectin, Zonulin, and sIgA Concentrations in the Stool of Adults Aged 18-74 Years

Alterations to the intestinal barrier may be involved in the pathogenesis of various chronic diseases. The diagnosis of mucosal barrier disruption has become a new therapeutic target for disease prevention. The aim of this study was to determine whether various patient demographic and biometric data, often not included in diagnostic analyses, may affect calprotectin, zonulin, and sIgA biomarker values. Stool markers' levels in 160 samples were measured colorimetrically. The analysis of twenty key bacteria (15 genera and 5 species) was carried out on the basis of diagnostic tests, including cultures and molecular tests. The concentrations of selected markers were within reference ranges for most patients. The sIgA level was significantly lower in participants declaring probiotics supplementation (p = 0.0464). We did not observe differences in gastrointestinal discomfort in participants. We found significant differences in the sIgA level between the 29-55 years and >55 years age-related intervals groups (p = 0.0191), together with a significant decreasing trend (p = 0.0337) in age-dependent sIgA concentration. We observed complex interdependencies and relationships between their microbiota and the analyzed biomarkers. For correct clinical application, standardized values of calprotectin and sIgA should be determined, especially in elderly patients. We observed a correlation between the composition of the gut community and biomarker levels, although it requires further in-depth analysis.

Diagnostic Value of Fecal Calprotectin in Children with Gastritis, Duodenitis and Helicobacter Pylori

Background

Fecal calprotectin (FC) is suggested as a novel biomarker for the diagnosis of gastrointestinal (GI) diseases; however, few studies have investigated its diagnostic value for Helicobacter pylori (H. pylori). Therefore, the current study evaluated the level of FC and its diagnostic value in patients with H. Pylori and its related conditions including gastritis and duodenitis.

Methods

In this case-control study, 120 children with upper GI symptoms, who were indicated to undergo upper GI endoscopic examination, were consecutively included. Patients were categorized into different groups based on their endoscopic findings including H. pylori, gastritis, duodenitis or normal.

Results

Patients with gastritis (P = 0.014) and those with duodenitis (P < 001) had significantly higher FC. The level of FC was higher in patients with H. pylori but this difference was marginally significant (P = 0.054). The level of FC had poor ability to diagnose the presence of H. pylori (P = 0.054) and gastritis (area under the curve, AUC = 0.639, P = 0.014). However, it had acceptable power to diagnose patients with or duodenitis (AUC = 0.718, P < 0.001). The sensitivity and specificity of FC for diagnosis of gastritis were 64 and 65 percent (cut-off = 45.2 μg/g), and for duodenitis were 77 and 61 percent (cut-off = 46.2 μg/g), respectively.

Conclusions

FC can be considered as an objective and diagnostic tool for duodenitis. However, due to the low sensitivity and specificity, it is suggested to consider it as an objective supplementary test beside other established diagnostic modalities.

The role of faecal calprotectin in diagnosis and staging of colorectal neoplasia: a systematic review and meta-analysis

Introduction

The presence of inflammation is a key hallmark of cancer and, plays an important role in disease progression and survival in colorectal cancer (CRC). Calprotectin detected in the faeces is a sensitive measure of colonic inflammation. The role of FC as a diagnostic test that may categorise patients by risk of neoplasia is poorly defined. This systematic review and meta-analysis aims to characterise the relationship between elevations of FC and colorectal neoplasia.

Methods

A systematic review was performed using the keywords (MESH terms) and a statistical and meta-analysis was performed.

Results

A total of 35 studies are included in this review. CRC patients are more likely than controls to have an elevated FC OR 5.19, 95% CI 3.12–8.62, p < 0.001 with a heterogeneity (I² = 27%). No tumour characteristics significantly correlated with FC, only stage of CRC shows signs that it may potentially correlate with FC.

Conclusion

FC levels are significantly higher in CRC, with high sensitivity. Its low specificity prevents it from being used to diagnose or screen for CRC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02220-1.

Self-reported flares among people living with IBD are associated with stress and worry but not associated with recent diet changes: The Manitoba Living with IBD Study

BACKGROUND

In this matched case-control longitudinal study among people living with inflammatory bowel disease (IBD), we investigated beliefs about what triggers a flare.

METHODS

Adults with confirmed IBD and active disease within 2 years were enrolled in the Manitoba Living with IBD Study and followed biweekly with online surveys for 1 year. The 7-point IBD Symptom Change Indicator was used for participant identification of a flare. Flare cases were matched to non-flare controls by sex and disease type. Members of each matched pair completed supplemental information on diet changes and psychological functioning in the previous two weeks, and provided stool samples to assess fecal calprotectin (FCAL).

RESULTS

Of 128 enrolled participants, 95 matched flare/non-flare pairs were created. Those reporting a flare were more likely to have elevated FCAL (51% vs 34% among non-flares, p=0.043). Although 61% of study participants believed at baseline that a food may trigger flares, and 25% of those in a flare believed that a food may have triggered their current flare, there was no difference in consumption of assessed foods between flares and non-flares in the previous two weeks. Flares were more likely to be having difficulties in emotional state than controls (40% vs 18%, p=0.001) and more likely to be stressed or worried (64% vs 33%, p=0.001).

CONCLUSION

While a majority of individuals with IBD believe that specific foods trigger their disease flares, this was not supported by the current findings. Recent psychological functioning was associated with self-reported IBD flare. This article is protected by copyright. All rights reserved.

The role of faecal calprotectin in the identification of colorectal neoplasia in patients attending for screening colonoscopy

AIM

Although the relationship between colorectal neoplasia and inflammation is well described, the role of faecal calprotectin (FC) in clinical practice to diagnose or screen patients for colorectal neoplasia is less defined. This prospective study characterizes the relationship between FC and colorectal neoplasia in patients within the faecal occult blood testing (FOBT) positive patients in the Scottish Bowel Screening Programme.

METHODS

All FOBT positive patients attending for colonoscopy between February 2016 and July 2017 were invited to participate. Patients provided a stool sample for FC before commencing bowel preparation. All demographics and endoscopic findings were collected prospectively.

RESULTS

In all, 352 patients were included. 210 patients had FC > 50 µg. Colorectal cancer (CRC) patients had a higher median FC (138.5 μg/g, P < 0.05), in comparison to those without CRC, and 13/14 had an FC > 50 µg/g (93%). FC had a high sensitivity (92.8%) and negative predictive value (99.3%) for CRC, but with a low specificity (41.7%) and positive predictive value (6.2%). FC sensitivity increased sequentially as neoplasms progressed from non-advanced to malignant neoplasia (48.6% non-advanced adenoma vs. 92.9% CRC). However, no significant relationship was observed between FC and non-cancer neoplasia.

CONCLUSION

In an FOBT positive screening population, FC was strongly associated with CRC (sensitivity 92.8%, specificity 41.7% for CRC, at 50 µg/g). However, although sensitive for the detection of CRC, FC failed to show sufficient sensitivity or specificity for the detection of non-cancer neoplasia. Based on these results we cannot recommend routine use of FC in a bowel screening population to detect cancer per se, but it is apparent that, with further optimization, faecal assessments including quantification of haemoglobin and inflammation could form part of a risk assessment tool aimed at refining the selection of patients for colonoscopy in both symptomatic and screening populations.

Calprotectin: from biomarker to biological function

The incidence of inflammatory bowel diseases (IBD) emerged with Westernisation of dietary habits worldwide. Crohn's disease and ulcerative colitis are chronic debilitating conditions that afflict individuals with substantial morbidity and challenge healthcare systems across the globe. Since identification and characterisation of calprotectin (CP) in the 1980s, faecal CP emerged as significantly validated, non-invasive biomarker that allows evaluation of gut inflammation. Faecal CP discriminates between inflammatory and non-inflammatory diseases of the gut and portraits the disease course of human IBD. Recent studies revealed insights into biological functions of the CP subunits S100A8 and S100A9 during orchestration of an inflammatory response at mucosal surfaces across organ systems. In this review, we summarise longitudinal evidence for the evolution of CP from biomarker to rheostat of mucosal inflammation and suggest an algorithm for the interpretation of faecal CP in daily clinical practice. We propose that mechanistic insights into the biological function of CP in the gut and beyond may facilitate interpretation of current assays and guide patient-tailored medical therapy in IBD, a concept warranting controlled clinical trials.

Clinical Value of Fecal Calprotectin in Predicting Mucosal Healing in Patients With Ulcerative Colitis

Aim: This study aimed to evaluate the clinical significance of fecal calprotectin (FC) in assessment of ulcerative colitis (UC) patients' endoscopic patterns and clinical manifestation.

Methods: A total of 143 UC patients who received colonoscopy and 108 controls were included. After providing stool samples, patients underwent total colonoscopy. FC was measured by an enzyme-linked immunosorbent assay (ELISA). Clinical activity was based on the Mayo score. Endoscopic findings was scored by the Ulcerative Colitis Endoscopic Index of Severity (UCEIS). Correlation analysis and receiver-operator characteristic (ROC) analysis were carried out to determine the significance of measurements.

Results: The median (interquartile range, IQR) of FC levels was 211 (43–990) μg/g in UC and 87.5 (40.50~181) μg/g in the control group. Fecal calprotectin correlated significantly with both Mayo and UCEIS scores (Spearman's r 0.670 and 0.592, P < 0.01). With a cut-off value of 164 μg/g for fecal calprotectin concentration, the area under the curve (AUC) in receiver operator characteristic analysis was 0.830, sensitivity was 85.42%, specificity was 73.68%, positive predictive value (PPV) was 62.12%, and negative predictive value (NPV) was 9.10% in predicting clinical active disease. Similarly, the power of FC to predict mucosal healing (MH) was modest. With a cut-off value of 154.5 μg/g, the AUC was 0.839, sensitivity was 72.34%, and specificity was 85.71%.

Conclusion: For evaluating the disease activity of UC, FC is a clinically relevant biomarker for both clinically active disease and MH in patients with UC. But the cut-off value still needs large and multicenter studies for confirmation.

Diagnostic accuracy of fecal calprotectin in predicting significant gastrointestinal diseases

Background and Aim

It is often unreliable to triage patients for timely endoscopic investigations based on symptoms alone. We need an objective assessment to differentiate between organic gastrointestinal diseases and functional bowel symptoms. We evaluated the diagnostic accuracy of fecal calprotectin (FC) in predicting organic gastrointestinal diseases.

Methods

In a prospective observational study, consecutive patients referred for colonoscopy to the Department of Medicine and Geriatrics at the Kwong Wah Hospital in Hong Kong were recruited. Stool samples were collected within 24 h before colonoscopy. FC was measured by a commercial kit. Upper endoscopy investigations were then proceeded if normal colonoscopy but elevated FC.

Results

Two hundred and seventy out of 429 patients had FC above 50 μg/g. Eighty‐six out of 270 with elevated FC had significant colonoscopy pathological findings. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of FC test for diagnosing a significant organic colonoscopy or upper endoscopy disease were 91.7, 55.6, 57.0, and 91.2%, respectively. The NPV of FC for colorectal cancer, high risk polyp, and colon inflammation were 98.7, 96.2, and 98.1%, respectively. The NPV of FC in the condition of altered bowel habit or abdominal pain in predicting colorectal cancer and inflammation were 93.8 and 100%, respectively.

Conclusions

FC is a reliable marker of ruling out organic bowel diseases. A single negative FC test could be used as a triage tool to prioritize the need and urgency of further investigation, particularly in the setting of altered bowel habits and abdominal pain.

Microbial genetic and transcriptional contributions to oxalate degradation by the gut microbiota in health and disease

Over-accumulation of oxalate in humans may lead to nephrolithiasis and nephrocalcinosis. Humans lack endogenous oxalate degradation pathways (ODP), but intestinal microbes can degrade oxalate using multiple ODPs and protect against its absorption. The exact oxalate-degrading taxa in the human microbiota and their ODP have not been described. We leverage multi-omics data (>3000 samples from >1000 subjects) to show that the human microbiota primarily uses the type II ODP, rather than type I. Furthermore, among the diverse ODP-encoding microbes, an oxalate autotroph, Oxalobacter formigenes, dominates this function transcriptionally. Patients with inflammatory bowel disease (IBD) frequently suffer from disrupted oxalate homeostasis and calcium oxalate nephrolithiasis. We show that the enteric oxalate level is elevated in IBD patients, with highest levels in Crohn's disease (CD) patients with both ileal and colonic involvement consistent with known nephrolithiasis risk. We show that the microbiota ODP expression is reduced in IBD patients, which may contribute to the disrupted oxalate homeostasis. The specific changes in ODP expression by several important taxa suggest that they play distinct roles in IBD-induced nephrolithiasis risk. Lastly, we colonize mice that are maintained in the gnotobiotic facility with O. formigenes, using either a laboratory isolate or an isolate we cultured from human stools, and observed a significant reduction in host fecal and urine oxalate levels, supporting our in silico prediction of the importance of the microbiome, particularly O. formigenes in host oxalate homeostasis.

Elevated Faecal Calprotectin in Patients with a Normal Colonoscopy: Does It Matter in Clinical Practice? A Retrospective Observational Study

Introduction

Faecal calprotectin (FC) is commonly used as a diagnostic tool for patients with gastrointestinal (GI) symptoms. However, there is uncertainty in daily clinical practice how to interpret an elevated FC in patients with a normal colonoscopy. We investigated if patients with a normal colonoscopy but with an elevated FC more often were diagnosed with a GI disease in a 3-year follow-up period.

Methods

Patients referred for colonoscopy (n = 1,263) to the Umeå University Hospital endoscopy unit between 2007 and 2013 performed a FC test (CALPRO^®) on the day before bowel preparation. A medical chart review was performed on all patients who had normal findings on their colonoscopy (n = 585, median age 64 years).

Results

Thirty-four percent of the patients (n = 202) with normal colonoscopy had elevated FC (>50 μg/g), and these patients were more frequently diagnosed with upper GI disease during the follow-up period than patients with normal FC levels (9.9 vs. 4.7%; p = 0.015). The upper GI diseases were mainly benign (i.e., gastritis). In a binary logistic regression analysis controlling for age, gender, nonsteroid anti-inflammatory drug use, and proton-pump inhibitor use, there was no difference for a new diagnosis of upper GI disease in the follow-up period (multivariate OR 1.70; 95% CI: 0.77-3.74). There was no difference in a new diagnosis of lower GI disease (6.4 vs. 5.2%; p = 0.545) or cardiovascular disease/death (multivariate OR 1.68; 95% CI: 0.83-3.42) in the follow-up period between patients with elevated versus normal FC levels.

Conclusions

In patients with a normal colonoscopy, a simultaneously measured increased FC level was not associated with an increased risk for significant GI disease during a follow-up period of 3 years.

Elevated Intestinal Inflammation in Preterm Infants With Signs and Symptoms of Gastroesophageal Reflux Disease

OBJECTIVES

Reflux is common in infancy; however, persistent signs and symptoms of gastrointestinal distress are often attributed to gastroesophageal reflux disease (GERD). In this pilot study, we aimed to characterize associations between signs and symptoms of suspected GERD and noninvasive markers of intestinal inflammation in preterm infants.

METHODS

We reviewed Electronic Medical Record (EMR) data to identify clinical signs and symptoms among case patients (n = 16). Controls (n = 16) were matched on gestational age. Univariate and multivariate regression analyses were used to compare fecal calprotectin and urinary intestinal fatty acid binding protein (I-FABP) levels between cases and controls.

RESULTS

We found no differences in baseline characteristics between cases and controls. In the multivariate regression analysis controlling for the proportion of mother's milk, cases had higher fecal calprotectin levels than controls, with no differences in I-FABP levels between cases and controls.

CONCLUSION

Our findings suggest that preterm infants with signs and symptoms of GERD have higher levels of intestinal inflammation as indicated by fecal calprotectin compared to their controls. Further studies are needed to evaluate the role of intestinal inflammation in signs and symptoms of gastrointestinal distress and whether fecal calprotectin might have predictive value in diagnosing GERD.

Fecal calprotectin levels used as a noninvasive method for screening for chronic gastritis in pediatric patients. A descriptive study

BACKGROUND

Gastritis consists of inflammation of the gastric mucosa and is one of the main causes of dyspeptic symptoms in children.

OBJECTIVE

To investigate the presence of inflammation by evaluating fecal calprotectin (FC) in children diagnosed with chronic gastritis.

DESIGN AND SETTING

Descriptive study in Pediatric Gastroenterology Department of Ondokuz Mayis University Hospital in Turkey.

METHODS

Between January 2016 and July 2018, FC levels were compared retrospectively in children with chronic gastritis (histopathology-based diagnosis), patients with inflammatory bowel disease (IBD) and healthy children.

RESULTS

A total of 67 chronic gastritis patients (61.2% girls) with a mean age of 13.09 ± 3.5 years were evaluated. The mean FC levels were 153.4 μg/g in the chronic gastritis group, 589.7 μg/g in the IBD group and 43.8 μg/g in the healthy group. These levels were higher in chronic gastritis patients than in healthy individuals (P = 0.001) and higher in IBD patients than in the other two groups (P < 0.001). The FC level in the patients with chronic active gastritis (156.3 μg/g) was higher than in those with chronic inactive gastritis (150.95 μg/g) (P = 0.011). Among the patients with chronic active gastritis, the FC level was significantly higher in Helicobacter pylori-positive individuals than in negative individuals (P = 0.031).

CONCLUSION

We confirmed the association between increased FC and chronic gastritis. Elevated FC levels may be seen in patients with chronic active gastritis. In order to be able to use FC as a screening tool for chronic gastritis, further studies in a larger study group are needed.

Association Between Change in Inflammatory Aspects of Diet and Change in IBD-related Inflammation and Symptoms Over 1 Year: The Manitoba Living With IBD Study

BACKGROUND

We aimed to investigate (1) the stability of inflammatory aspects of diet over 1 year among persons with inflammatory bowel disease (IBD) and (2) the impact of change in diet on changes in inflammation and IBD symptoms over 1 year.

METHODS

Participants were recruited to the Manitoba Living with IBD Study and completed the Harvard Food Frequency Questionnaire (FFQ). The Dietary Inflammatory Index (DII) and the Empirical Dietary Inflammatory Index (EDII) were used to calculate the inflammatory potential of the diet. Inflammation was measured by fecal calprotectin (≥250 µg/g). Symptoms were measured by the IBD Symptom Inventory (IBDSI). All measures were obtained at baseline and 1 year. Dietary Inflammatory Index and Empirical Dietary Inflammatory Index scores >0 and <0 reflect pro- and anti-inflammatory diet, respectively. Variance components analyses were used to describe diet stability. Associations between changes in diet and changes in active inflammation and symptoms were assessed using ordinal logistic regression and multilevel linear regression modeling.

RESULTS

One hundred thirty-five participants (66% CD) were included. Approximately one third of the variance in EDII (36%) and DII (33%) scores was explained by changes in diet over time. Each unit increase in the change in EDII (baseline to follow-up) was associated with a greater odds of FCAL, indicating active inflammation (>250 µg/g; odds ratio, 3.1; 95% confidence interval [CI], 1.02-9.93; P = 0.04) and with a rise in IBDSI of 6.7 (95% CI, 1.0-12.4; P = 0.022; theoretical IBDSI range, 0-81). There was no association between changes in DII and changes in FCAL or IBDSI.

CONCLUSION

The EDII, but not the DII, may have utility to identify the inflammatory potential of diet. This inflammatory potential can contribute to inflammation and/or disease symptoms in persons with IBD.

Evaluation of a fluorescent immunochromatography test for fecal calprotectin

BACKGROUND

Fecal calprotectin (FC) is widely used to discriminate between patients with inflammatory diseases such as inflammatory bowel disease (IBD) and functional diseases such as irritable bowel syndrome (IBS). ELISA is a time-consuming method for the measurement of FC, whereas a fluorescent immunochromatography test can obtain results in around 30 minutes and thus enables a rapid response to clinical decision.

METHODS

Two methods, the Proglead^® calprotectin (FC Proglead) and the BÜHLMANN fCAL^® ELISA (FC BÜHLMANN), were used to quantitatively examine FC in 111 stool samples. The comparison and bias estimation of both assays were assessed using CLSI EP09c protocol.

RESULTS

The two methods were highly correlated (rho = .96). Deming regression was employed to calculate the regression equation, with a slope of 1.01 and an intercept of -4.98 μg/g. The estimated median bias (FC Proglead - FC BÜHLMANN) was -4.19 μg/g with the 95% limits of agreement (-55.59 to 47.21 μg/g), and the estimated median percent bias was -8.71% with the 95% limits of agreement (-50.31% to 32.90%). There was 4.50% (5/111) of values outside the 95% limits of agreement. Percent biases at the FC cutoff values of 50 and 200 μg/g between both methods evaluated by Deming regression were 8.96% and 1.49%, respectively. The biases were all less than the acceptable standard (10%). And, 99.10% of FC results were in agreement between both methods (kappa = .99, P < .001).

CONCLUSIONS

FC Proglead may be used as a suitable alternative to FC BÜHLMANN for the disease activity assessment for patients with IBD, considering its convenience and shorter turnaround time.

Diagnostic value of fecal B cell activating factor in patients with abdominal discomfort

Fecal calprotectin has successfully been widely recommended as a sensitive biomarker of inflammatory bowel diseases (IBD). Recently, we have identified an excellent new fecal biomarker, B cell activating factor (BAFF), as being as effective as fecal calprotectin for diagnosing intestinal inflammation. In this study, a total of 230 patients with abdominal discomfort were prospectively enrolled and fecal samples were collected within 24 h before the endoscopic examinations. We show that fecal BAFF levels were significantly higher in patients with ulcerative colitis (median = 1549 pg/g, P < 0·0001), Crohn's disease (median = 735 pg/g, P < 0·0001), gastric cancer (median = 267 pg/g, P < 0·0001) and colorectal cancer (median = 533 pg/g, P < 0·0001) than those in healthy groups (median = 61 pg/g), while the values of which in patients with gastric polyps, colorectal polyps, esophagitis/gastritis/duodenitis and peptic ulcer were in the range of healthy individuals (P > 0·05). An optimal cut-off value at 219·5 pg/g of fecal BAFF produced sensitivity, specificity, positive predictive and negative predictive values of 85, 91, 84 and 92%, respectively, for IBD or carcinoma. Our results therefore indicate a potential role for fecal BAFF as a sensitive screening parameter for IBD and gastrointestinal carcinoma, as well a useful tool to select patients with abdominal discomfort for further endoscopic examinations.

Biomarkers of inflammatory bowel disease activity

The review presents data on calprotectin, lactoferrin, leukocytes labeled with isotope indium 111In, calgranulin C and pyruvate kinase type M2 - highly sensitive biomarkers to assess the severity of intestinal inflammation. Their importance in diagnostics, determination of treatment efficiency, including as predictors of recurrence of ulcerative colitis and Crohn's disease is shown.

Living With Inflammatory Bowel Disease: Protocol for a Longitudinal Study of Factors Associated With Symptom Exacerbations

BACKGROUND

There has been limited longitudinal research that has comprehensively evaluated possible factors in the exacerbation of inflammatory bowel disease (IBD) symptoms with or without associated inflammation. Evolving Web-based technologies facilitate frequent monitoring of patients' experiences and allow a fine-grained assessment of disease course.

OBJECTIVE

We aimed to prospectively identify factors associated with symptom exacerbation and inflammation in IBD including psychological functioning, diet, health behaviors, and medication adherence.

METHODS

Between June 2015 and May 2017, we enrolled adults with IBD, recruited from multiple sources, who had been symptomatically active at least once within the prior 2 years. They completed a Web-based survey every 2 weeks for 1 year and submitted a stool sample at baseline, 26 weeks, and 52 weeks. Any participant reporting a symptom exacerbation was matched to a control within the cohort, based on disease type, sex, age, and time of enrollment; both were sent a supplemental survey and stool collection kit. Biweekly surveys included validated measures of the disease course, psychological functioning, health comorbidities, and medication use. Intestinal inflammation was identified through fecal calprotectin (positive level >250 μg/g stool).

RESULTS

There were 155 participants enrolled with confirmed IBD, 66.5% (103/155) with Crohn disease and 33.5% (52/155) with ulcerative colitis, of whom 98.7% (153/155) completed the study. Over the 1-year period, 47.7% (74/155) participants experienced a symptom exacerbation. The results of analyses on risk factors for symptom exacerbations are pending.

CONCLUSIONS

We recruited and retained a longitudinal IBD cohort that will allow the determination of risk factors for symptom exacerbation with and without inflammation. This will increase understanding of symptom exacerbations among persons with IBD.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR1-10.2196/11317.

Faecal Calprotectin

Calprotectin is a calcium- and zinc-binding protein of the S-100 protein family which is mainly found within neutrophils and throughout the human body. The presence of calprotectin in faeces is a consequence of neutrophil migration into the gastrointestinal tissue due to an inflammatory process. Faecal calprotectin concentrations demonstrate good correlation with intestinal inflammation and faecal calprotectin is used as a biomarker in gastrointestinal disorders. Faecal calprotectin is a very sensitive marker for inflammation in the gastrointestinal tract, and useful for the differentiation of inflammatory bowel disease (IBD) from irritable bowel syndrome (IBS). Faecal calprotectin is used for the diagnosis, monitoring disease activity, treatment guidance and prediction of disease relapse and post-operative recurrence in IBD. There may also potentially be a role for faecal calprotectin in the management of infectious gastroenteritis, acute appendicitis, peptic ulcer disease, cystic fibrosis, coeliac disease, transplant rejection and graft versus host disease. Further studies are needed to confirm its utility in these conditions. Analysis of faecal calprotectin consists of an extraction step followed by quantification by immunoassay. Over the past few decades, several assays and extraction devices including point-of-care methods have been introduced by manufacturers. The manufacturer-quoted cut-off values for different faecal calprotectin assays are generally similar. However, the sensitivities and specificities at a given cut-off, and therefore the optimum cut-off values, are different between assays. A reference standard for calprotectin is lacking. Therefore, assay standardisation is required for more accurate and traceable test results for faecal calprotectin.

Diagnostic Accuracy of Serum and Urine S100A8/A9 and Serum Amyloid A in Probable Acute Abdominal Pain at Emergency Department

Study Design

This study was performed to investigate the diagnostic values of some inflammatory biomarkers in abdominal pain.

Methods

Patients over 18 years of age with acute recent abdominal pain who presented to the Emergency Department were evaluated. Serum and urinary samples were taken and evaluated for serum and urine S100A8/A9 and serum amyloid A. All patients were referred to a surgeon and were followed up until the final diagnosis. In the end, the final diagnosis was compared with the levels of biomarkers.

Results

Of a total of 181 patients, 71 underwent surgery and 110 patients did not need surgery after they were clinically diagnosed. Mean levels of serum and urine S100A8/A9 had a significant difference between two groups, but serum amyloid A did not show. The diagnostic accuracy of serum S100A8/A9, urine S100A8/A9, and serum amyloid A was 86%, 79%, and 50%, respectively, in anticipation of the need or no need for surgery in acute abdominal pain.

Conclusions

Our study showed that in acute abdominal pain, serum and urine S100A8/A9 can be useful indicators of the need for surgery, but serum amyloid A had a low and nonsignificant diagnostic accuracy.

The Vampire Study: Significant elevation of faecal calprotectin in healthy volunteers after 300 ml blood ingestion mimicking upper gastrointestinal bleeding

Background

Faecal calprotectin correlates with histological and clinical activity in inflammatory bowel disease. Gastrointestinal bleeding might also increase faecal calprotectin levels, erroneously implying intestinal inflammation; however, this possibility has not been systematically assessed.

Methods

Sixteen healthy volunteers without gastrointestinal disease and normal faecal calprotectin baseline values ingested their own blood twice, either by drinking or via nasogastric tube. Quantities of 100 ml and 300 ml blood were ingested in a randomised order, with a 28-day wash-out period. Faecal calprotectin, faecal occult blood test, and the occurrence of melaena were assessed. Faecal calprotectin ≥ 50 µg/g was considered elevated.

Results

Melaena was reported by all healthy volunteers after 300 ml and by 11/15 healthy volunteers (71%) after 100 ml blood ingestion. One day after ingestion of 300 ml blood, 8/16 faecal calprotectin tests were positive compared to 1/16 at baseline (p = 0.016). Faecal calprotectin levels above > 200 µg/g were rarely observed. There was a trend for faecal calprotectin test positivity also after ingestion of 100 ml.

Conclusion

Ingestion of blood resulted in an increase in faecal calprotectin-positive tests. Gastrointestinal bleeding should be considered as a potential cause of mild faecal calprotectin elevation > 50 µg/g; however, increased faecal calprotectin above > 250-300 µg/g, the established cut-off for relevant intestinal inflammation in patients with inflammatory bowel disease, is rare.

Upregulation of calprotectin in mild IgE-mediated ovalbumin hypersensitivity

Calprotectin, also known as S100A8/A9, has been linked to gut inflammation caused by IgE-mediated food hypersensitivities, but the pathophysiologic abnormalities it causes remain to be determined. We created a mild food hypersensitivity model through oral gavage of ovalbumin in Norway brown rats without using immune adjuvant. Changes in the levels of calprotectin and inflammation-associated cytokines were then observed over time. We found that fecal calprotectin as well as jejunal and liver TLR4, TNF-α, NF-κB, IL-1β, and IL-6 were upregulated in hypersensitive rats. Additionally, the influence of calprotectin on CD4⁺ T and dendritic cells was observed by co-culturing CD4⁺ T cells with dendritic cells, which revealed a shift toward increased Th2 T cells in calprotectin-treated cultures. These results suggest that calprotectin, along with other inflammatory factors, promotes the inflammation seen in mild food allergy.

Fecal Calprotectin: A Comparison of Two Commercial Enzymoimmunoassays and Study of Fecal Extract Stability at Room Temperature

Background

The aims of the study were: 1) to compare the fecal calprotectin (fCal) assay results with Calprolab™ ELISA (HRP) (Calpro AS) versus our routine method, Elia™ fluoroenzymoimmunoassay (Thermo Fisher), and 2) to determine whether the fCal assay results do not vary following storage of the extract at room temperature for 4 days with the Calpro AS buffer, this being the estimated shipment time from the home of the patient, and an aspect little studied to date.

Methods

The fCal was determined in 198 patients divided into three groups: inflammatory bowel disease (IBD), organic intestinal disease, and functional intestinal disorders. Fecal extraction was carried out using the Roche Diagnostics kit with the corresponding specific buffers.

Results

The fCal assay with the Thermo Fisher method was found to be more sensitive but less specific than with the Calpro AS technique. The positive predictive value was low (just over 50%), though the negative predictive value was high (over 90%) with both methods. The likelihood ratios revealed small but occasionally important pre- versus post-test differences. When we compared the two methods, the Spearman correlation coefficient (ρ) was 0.819 (95% CI: 0.768 - 0.860) (P < 0.0001), reflecting a positive correlation. Similarly, when stratifying the fCal results into < 50 µg/g, 50 - 100 µg/g and > 100 µg/g, the resulting Cohen’s kappa coefficient was 0.7766 (95% CI: 0.7025 - 0.8507), reflecting a substantial agreement between both methods. The stability of fCal was high in fecal extracts with the Calpro AS extraction buffer at room temperature for 4 days, which yielded a Spearman correlation coefficient of 0.951 (95% CI: 0.933 - 0.965), when the results were compared to those of the recent extracts (P < 0.0001).

Conclusions

A positive correlation was observed between the two methods. In view of the high negative predictive value obtained with fCal, the presence of organic disease is highly unlikely in the presence of a normal concentration of this marker. We also confirmed the excellent stability of fCal in fecal extracts with the Calpro AS extraction buffer stored at room temperature. Thus, and for the sake of convenience and hygiene, it would be ideal for the patient to perform the extraction at home.

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

Background

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

Methods

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

Results

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

Conclusion

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

The utility of fecal calprotectin in predicting the need for escalation of therapy in inflammatory bowel disease

BACKGROUND AND AIMS

Fecal calprotectin is an important biomarker used in the evaluation of inflammatory bowel disease. It has proven to be an effective tool in initial screening as well monitoring response to therapy. The aim of this study is to examine the utility of fecal calprotectin both as a predictor for the escalation of therapy in established inflammatory bowel disease and as a predictor of de novo diagnosis.

METHODS

Patients with signs and symptoms concerning for inflammatory bowel disease presenting to outpatient clinics were recruited to provide fecal calprotectin stool samples prior to endoscopic evaluation. Patients were followed up for at least one year and monitored clinically for any change in symptomatology, escalation of therapy or development of IBD, confirmed endoscopically.

RESULTS

A total of 126 patients, of whom 72 were known to have underlying inflammatory bowel disease, were included in the final analysis. Among the patients with elevated fecal calprotectin levels and known inflammatory bowel disease, 66% (33/50) went on to have escalation of therapy within 12 months compared to 18% (4/22) if the fecal calprotectin levels were in the normal range (p < .0001). For the remaining patients who at baseline did not have inflammatory bowel disease and a normal endoscopic evaluation, elevated fecal calprotectin resulted in no cases (0/17) of a new diagnosis in the next 12 months.

CONCLUSIONS

Fecal calprotectin is a useful test for predicting escalation of therapy in established inflammatory bowel disease.

Fecal calprotectin in juvenile idiopathic arthritis patients related to drug use

BACKGROUND

Patients with juvenile idiopathic arthritis (JIA) on non-steroidal anti- inflammatory drugs (NSAIDs) may experience abdominal pain. In adults, NSAID use has been linked to an increase in fecal calprotectin (FC) levels, a surrogate marker for gut inflammation. In JIA, data on gut inflammation related to drug use is scarce.

METHODS

JIA patients followed up at the outpatient pediatric rheumatology clinic in Children's Hospital, Helsinki University Hospital, Helsinki, Finland were routinely assessed for FC if they complained about abdominal pain, had an elevated erythrocyte sedimentation rate (ESR) or used NSAIDs on a daily basis. The FC levels were related to the presence of abdominal pain, to ESR, and to the presence of HLA-B27.

RESULTS

Of the total group of 90 patients (median age 9.1 years; 45 JIA patients with disease modifying anti-rheumatic drugs (DMARDs), 25 without DMARD medication, and 20 arthralgia patients as controls), approximately 50% used NSAIDs, of whom 40% complained about abdominal pain. In patients with abdominal pain, one-third had elevated FC values (>100 μg/g). The FC values, for the most part, declined along with the discontinuation or reduction of NSAIDs and after intensifying the DMARD medication, where after the pain disappeared. In patients with an elevated ESR, the FC values and ESR normalized in parallel. The presence of HLA-B27 was not associated with FC levels.

CONCLUSION

In patients with JIA and abdominal pain, it may be useful to determine the FC when evaluating the need for further gastrointestinal examinations.

Diagnosing colorectal cancer and inflammatory bowel disease in primary care: The usefulness of tests for faecal haemoglobin, faecal calprotectin, anaemia and iron deficiency. A prospective study

OBJECTIVE

Abdominal complaints are common reasons to consult primary care but they are seldom caused by colorectal cancer (CRC), high-risk adenomas (HRAs), or inflammatory bowel disease (IBD). Reliable diagnostic aids would be helpful in deciding which patients to refer for bowel imaging. Our aim was to assess the value of a faecal immunochemical test (FIT) and a faecal calprotectin (FC) test in detecting CRC, HRAs and IBD in primary care, and the value of combining these tests with anaemia and iron-deficiency tests.

MATERIALS AND METHODS

This prospective study included 373 consecutive patients that received a FIT or a FC test ordered by a primary care physician. We collected samples for FITs, FC tests, full blood counts and iron-deficiency tests. Physicians were instructed to refer patients with a positive FIT or FC test (cut-off ≥100μg/g) for bowel imaging. The patients' presenting symptoms were recorded. Patients were followed for 2 years.

RESULTS

The best test for detecting CRC and IBD was the combination of the FIT and haemoglobin concentration. This test had a sensitivity, specificity, positive predictive value and negative predictive value of 100%, 61.7%, 11.7% and 100%, respectively. The FIT detected a significantly larger proportion of CRC, HRAs and IBD than the FC test (0.92 versus 0.46, 95% confidence interval 0.22-0.67).

CONCLUSION

A negative FIT combined with a normal haemoglobin concentration could rule out CRC and IBD with a high degree of safety. This could be useful in prioritising referrals for bowel imaging from primary care.

Intestinal dysbiosis is common in systemic sclerosis and associated with gastrointestinal and extraintestinal features of disease

BACKGROUND

Recent evidence suggests a link between autoimmunity and the intestinal microbial composition in several rheumatic diseases including systemic sclerosis (SSc). The objective of this study was to investigate the prevalence of intestinal dysbiosis in SSc and to characterise patients suffering from this potentially immunomodulatory deviation.

METHODS

This study consisted of 98 consecutive patients subject to in-hospital care. Stool samples were analysed for intestinal microbiota composition using a validated genome-based microbiota test (GA-map™ Dysbiosis Test, Genetic Analysis, Oslo, Norway). Gut microbiota dysbiosis was found present as per this standardised test. Patients were examined regarding gastrointestinal and extraintestinal manifestations of SSc by clinical, laboratory, and radiological measures including esophageal cineradiography, the Malnutrition Universal Screening Tool (MUST), levels of plasma transthyretin (a marker of malnutrition) and faecal (F-) calprotectin (a marker of intestinal inflammation).

RESULTS

A majority (75.5%) of the patients exhibited dysbiosis. Dysbiosis was more severe (rs = 0.31, p = 0.001) and more common (p = 0.013) in patients with esophageal dysmotility. Dysbiosis was also more pronounced in patients with abnormal plasma levels of transthyretin (p = 0.045) or micronutrient deficiency (p = 0.009). In 19 patients at risk for malnutrition according to the MUST, 18 exhibited dysbiosis. Conversely, of the 24 patients with a negative dysbiosis test, only one was at risk for malnutrition. The mean ± SEM levels of F-calprotectin were 112 ± 14 and 45 ± 8 μg/g in patients with a positive and negative dysbiosis test, respectively. Dysbiosis was more severe in patients with skin telangiectasias (p = 0.020), pitting scars (p = 0.023), pulmonary fibrosis (p = 0.009), and elevated serum markers of inflammation (p < 0.001). However, dysbiosis did not correlate with age, disease duration, disease subtype, or extent of skin fibrosis.

CONCLUSIONS

In this cross-sectional study, intestinal dysbiosis was common in patients with SSc and was associated with gastrointestinal dysfunction, malnutrition and with some inflammatory, fibrotic and vascular extraintestinal features of SSc. Further studies are needed to elucidate the potential causal relationship of intestinal microbe-host interaction in this autoimmune disease.

Evaluation of a Multiplex Real-Time PCR Assay for Detecting Major Bacterial Enteric Pathogens in Fecal Specimens: Intestinal Inflammation and Bacterial Load Are Correlated in Campylobacter Infections

A total of 1,056 native or Cary-Blair-preserved stool specimens were simultaneously tested by conventional stool culturing and by enteric bacterial panel (EBP) multiplex real-time PCR for Campylobacter jejuni, Campylobacter coli, Salmonella spp., and shigellosis disease-causing agents (Shigella spp. and enteroinvasive Escherichia coli [EIEC]). Overall, 143 (13.5%) specimens tested positive by PCR for the targets named above; 3 coinfections and 109 (10.4%) Campylobacter spp., 17 (1.6%) Salmonella spp., and 20 (1.9%) Shigella spp./EIEC infections were detected. The respective positive stool culture rates were 75 (7.1%), 14 (1.3%), and 7 (0.7%). The median threshold cycle (CT) values of culture-positive specimens were significantly lower than those of culture-negative ones (CT values, 24.3 versus 28.7; P < 0.001), indicating that the relative bacterial load per fecal specimen was significantly associated with the culture results. In Campylobacter infections, the respective median fecal calprotectin concentrations in PCR-negative/culture-negative (n = 40), PCR-positive/culture-negative (n = 14), and PCR-positive/culture-positive (n = 15) specimens were 134 mg/kg (interquartile range [IQR], 30 to 1,374 mg/kg), 1,913 mg/kg (IQR, 165 to 3,813 mg/kg), and 5,327 mg/kg (IQR, 1,836 to 18,213 mg/kg). Significant differences were observed among the three groups (P < 0.001), and a significant linear trend was identified (P < 0.001). Furthermore, the fecal calprotectin concentrations and CT values were found to be correlated (r = -0.658). Our results demonstrate that molecular screening of Campylobacter spp., Salmonella spp., and Shigella spp./EIEC using the BD Max EBP assay will result in timely diagnosis and improved sensitivity. The determination of inflammatory markers, such as calprotectin, in fecal specimens may aid in the interpretation of PCR results, particularly for enteric pathogens associated with mucosal damage and colonic inflammation.

Comparison of Fecal Inflammatory Markers in Crohn's Disease

BACKGROUND

Fecal biomarkers are used increasingly to monitor Crohn's disease (CD). However, the relative accuracy of different markers in identifying inflammation has been poorly evaluated. We evaluated fecal calprotectin (FC), lactoferrin (FL), and S100A12 (FS) using endoscopic validation in a prospective study of the progression of CD after intestinal resection.

METHODS

Data were collected from 135 participants in a prospective, randomized, controlled trial aimed at preventing postoperative CD recurrence. Three hundred nineteen stool samples were tested for FC, FL, and FS preoperatively and 6, 12, and 18 months after resection. Colonoscopy was performed at 6 and/or 18 months. Endoscopic recurrence was assessed blindly using the Rutgeerts score. C-reactive protein (CRP) and Crohn's Disease Activity Index (CDAI) were assessed.

RESULTS

FC, FL, and FS concentrations were elevated preoperatively (median: 1347, 40.9, and 8.4 μg/g, respectively). At 6 months postoperatively, marker concentrations decreased (166, 3.0, 0.9 μg/g) and were higher in recurrent disease than remission (275 versus 72 μg/g, P < 0.001; 5.7 versus 1.6 μg/g, P = 0.007; 2.0 versus 0.8 μg/g, P = 0.188). FC > 135 μg/g, FL > 3.4 μg/g, and FS > 10.5 μg/g indicated endoscopic recurrence (score ≥ i2) with a sensitivity, specificity, and negative predictive value (NPV) of 0.87, 0.66, and 91%; 0.70, 0.68, and 81%; 0.91, 0.12, and 71%, respectively. FC and FL correlated significantly with the presence and severity of endoscopic recurrence, whereas FS, CRP and CDAI did not.

CONCLUSIONS

FC was the optimal fecal marker for monitoring disease activity in postoperative CD and was superior to CRP and CDAI. FL offered modest sensitivity for detecting recurrent disease, whereas S100A12 was sensitive but had low specificity and NPV.

Fecal Calprotectin in Healthy Children Aged 1-4 Years

Objective

Calprotectin has been well emulated recently in adults as well as in children. The aim of this study was to assess fecal calprotectin concentrations in healthy children aged from 1 to 4 years.

Methods

Volunteers were enlisted from 3 nurseries. A brief questionnaire was used to ensure these children meet the inclusion criteria, and some clinical and sociodemographic factors were collected. Anthro software (version 3.1) was used to calculated Length-for-age Z-scores (LAZ), weight-for-age Z-scores (WAZ), and weight-for-length Z-scores (WLZ) respectively. Fecal calprotectin was detected by a commercially available ELISA.

Results

In total 274 children were recruited, with age ranging from 1 to 4 years old. The median FC concentration was 83.19 μg/g [range 4.58 to 702.50 μg/g, interquartile range (IQR) 14.69–419.45 μg/g] or 1.92 log10 μg/g (range 0.66 log10 to 2.85 log10 μg/g, IQR 1.17 log10-2.62 log10 μg/g). All of the children were divided into three groups, 1–2 years (12–24 months), 2–3 years (24–36 months), 3–4 years (36–48 months), with median FC concentrations 96.14 μg/g (1.98 log10 μg/g), 81.48 μg/g (1.91 log10 μg/g), 65.36 μg/g (1.82 log10 μg/g), respectively. There was similar FC level between boys and girls. FC concentrations showed a downward trend by the growing age groups. A statistic difference was found in FC concentrations among groups 1–2 years, 2–3 years and 3–4 years (P = 0.016). In inter-groups comparison, a significant difference was found between children aged 1–2 years and children aged 3–4 years (P = 0.007). A negative correlation trend was found between age and FC concentration (Spearman's rho = -0.167, P = 0.005) in all the participants. A simple correlation was performed among WLZ, WAZ, birth weight, or birth length with FC, and there was no correlation being observed.

Conclusion

Children aged from 1 to 4 years old have lower FC concentrations compared with healthy infants (<1years), and higher FC concentrations when comparing with children older than 4 years and adults.

Current concepts on microscopic colitis: evidence-based statements and recommendations of the Spanish Microscopic Colitis Group

BACKGROUND

Microscopic colitis (MC) is an underdiagnosed inflammatory bowel disease.

AIM

To develop an evidence-based clinical practice guide on MC current concepts.

METHODS

Literature search was done on the Cochrane Library, EMBASE and MEDLINE electronic databases, which were consulted covering the period up until March 2015. Work groups were selected for each of the reviewed topics, with the purpose of drafting the initial statements and recommendations. They subsequently underwent a voting process based on the Delphi method. Each statement/recommendation was accompanied by the result of the vote the level of evidence, and discussion of the corresponding evidence. The grade of recommendation (GR) using the GRADE approach was established for diagnosis and treatment recommendations.

RESULTS

Some key statements and recommendations are: advancing age increases the risk of developing MC, mainly in females. The symptoms of MC and IBS-D may be similar. If MC is suspected, colonoscopy taking biopsies is mandatory. Treatment with oral budesonide is recommended to induce clinical remission in patients with MC. Oral mesalazine is not recommended in patients with collagenous colitis for the induction of clinical remission. The use of anti-TNF-alpha drugs (infliximab, adalimumab) is recommended for the induction of remission in severe cases of MC that fail to respond to corticosteroids or immunomodulators, as an alternative to colectomy.

CONCLUSIONS

This is the first consensus paper on MC based on GRADE methodology. This initiative may help physicians involved in care of these patients in taking decisions based on evidence.

Elevated levels of faecal calprotectin in primary Sjögren's syndrome is common and associated with concomitant organic gastrointestinal disease

Background

Primary Sjögren’s syndrome (pSS) is a systemic rheumatic disease in which gastrointestinal (GI) symptoms are common. Faecal calprotectin (FC) is a non-invasive biomarker that has been suggested to discriminate organic intestinal disease from functional disorders. The purpose of this study was to explore the usefulness of FC testing in patients with pSS.

Methods

In total, 56 consecutive patients with pSS and 29 healthy control subjects were included in this cross-sectional study. FC was measured with a commercially available enzyme-linked immunosorbent assay kit. GI symptoms were evaluated with the Rome III questionnaire and the Visual Analogue Scale for Irritable Bowel Syndrome. In patients with pSS, disease activity was estimated using the European League Against Rheumatism (EULAR) Sjögren’s Syndrome Disease Activity Index (ESSDAI), and patient-reported outcomes were evaluated with the EULAR Sjögren’s Syndrome Patient-Reported Index.

Results

Patients with pSS had higher levels of FC than healthy control subjects (median 54 μg/g, interquartile range [IQR 20–128]; vs. 20 μg/g [20–43]; p = 0.002). Concomitant organic GI disease was found in 14 patients with pSS and included inflammatory bowel disease (n = 3), colonic adenoma (n = 2) and GI lymphoma (n = 1). Patients with organic GI disease had higher FC levels than the other patients with pSS (median 274 μg/g [IQR 61–363] vs. median 34 μg/g [IQR 20–76]; p < 0.001). Although patients with pSS reported abdominal discomfort more frequently than healthy control subjects did, such symptoms were not associated with organic GI disease or elevated FC levels. FC correlated moderately with ESSDAI. Excluding patients with organic GI disease, we did not identify any significant association between ESSDAI and FC levels.

Conclusions

GI symptoms are frequent in pSS. Contrary to patient-reported outcomes, elevated FC levels in pSS indicate possible organic GI disease that warrants further investigation.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-015-0907-8) contains supplementary material, which is available to authorized users.

Fecal calprotectin is associated with disease activity in patients with ankylosing spondylitis

Calprotectin is one of the major antimicrobial S100 leucocyte proteins. Serum calprotectin levels are associated with certain inflammatory diseases such as rheumatoid arthritis, systemic lupus erythematosus and inflammatory bowel disease. The aim of this study was to investigate serum and fecal calprotectin levels in patients with ankylosing spondylitis (AS) and show their potential relations to the clinical findings of the disease. Fifty-one patients fulfilling the New York criteria of AS and 43 healthy age- and gender-matched volunteers were included in the study. Physical and locomotor system examinations were performed and history data were obtained for all patients. Disease activity parameters were assessed together with anthropometric parameters. Routine laboratory examinations and genetic testing (HLA-B27) were performed. Serum calprotectin levels and fecal calprotectin levels were measured by an enzyme-linked immunosorbent assay. The mean age of the patients was 41.5 years, the mean duration of the disease was 8.6 years, and the delay in diagnosis was 4.2 years. Serum calprotectin levels were similar in both AS patients and in the control group (p=0.233). Serum calprotectin level was correlated with Bath AS disease activity index (BASDAI) and Bath AS functional index (BASFI) (p=0.001, p=0.002, respectively). A higher level of fecal calprotectin was detected in AS patients when compared with the control group. A statistically significant correlation between fecal calprotectin level and BASDAI, BASFI, C-reactive protein and Erythrocyte sedimentation rate were detected (p=0.002, p=0.005, p=0.001, p=0.002, respectively). The results indicated that fecal calprotectin levels were associated with AS disease findings and activity parameters. Calprotectin is a vital disease activity biomarker for AS and may have an important role in the pathogenesis of the disease. Multi-centered prospective studies are needed in order to provide further insight.

FECAL CALPROTECTIN: levels for the ethiological diagnosis in Brazilian patients with gastrointestinal symptoms

BACKGROUND

Determination of fecal calprotectin can provide an important guidance for the physician, also in primary care, in the differential diagnosis of gastrointestinal disorders, meanly between inflammatory bowel diseases and irritable bowel syndrome. Objectives The aims of the present study were to prospectively investigate, in Brazilian adults with gastrointestinal complaints, the value of fecal calprotectin as a biomarker for the differential diagnosis between functional and organic disorders and to correlate the concentrations with the activity of inflammatory bowel diseases.

METHODS

The study included consecutive patients who had gastrointestinal complaints in which the measurement levels of fecal calprotectin were recommended. Fecal calprotectin was measured using a Bühlmann (Basel, Switzerland) ELISA kit.

RESULTS

A total of 279 patients were included in the study, with median age of 39 years (range, 18 to 78 years). After clinical and laboratorial evaluation and considering the final diagnosis, patients were allocated into the following groups: a) Irritable Bowel Syndrome: 154 patients (102 female and 52 male subjects). b) Inflammatory Bowel Diseases group: 112 patients; 73 with Crohn's disease; 38 female and 35 male patients; 52.1% (38/73) presented active disease, and 47.9% (35/73) had disease in remission and 39 patients with ulcerative colitis;19 female and 20 male patients; 48.7% (19/39) classified with active disease and 49.3% (20/39) with disease in remission. A significant difference (P<0.001) was observed between the median value of fecal calprotectin in Irritable Bowel Syndrome group that was 50.5 µg/g (IQR=16 - 294 µg/g); 405 µg/g (IQR=29 - 1980 µg/g) in Crohn's disease patients and 457 µg/g (IQR=25 - 1430 µg/g) in ulcerative colitis patients. No difference was observed between the values found in the patients with Crohn's disease and ulcerative colitis. Levels of fecal calprotectin were significantly lower in patients with inflammatory bowel diseases in remission when compared with active disease (P<0.001).

CONCLUSIONS

The present study showed that the determination of fecal calprotectin assists to differentiate between active and inactive inflammatory bowel diseases and between inflammatory bowel diseases and irritable bowel syndrome.

C-Reactive Protein, Fecal Calprotectin, and Stool Lactoferrin for Detection of Endoscopic Activity in Symptomatic Inflammatory Bowel Disease Patients: A Systematic Review and Meta-Analysis

OBJECTIVES

Persistent disease activity is associated with a poor prognosis in inflammatory bowel disease (IBD). Therefore, monitoring of patients with intent to suppress subclinical inflammation has emerged as a treatment concept. As endoscopic monitoring is invasive and resource intensive, identification of valid markers of disease activity is a priority. The objective was to evaluate the diagnostic accuracy of C-reactive protein (CRP), fecal calprotectin (FC), and stool lactoferrin (SL) for assessment of endoscopically defined disease activity in IBD.

METHODS

Databases were searched from inception to November 6, 2014 for relevant cohort and case-control studies that evaluated the diagnostic accuracy of CRP, FC, or SL and used endoscopy as a gold standard in patients with symptoms consistent with active IBD. Sensitivities and specificities were pooled to generate operating property estimates for each test using a bivariate diagnostic meta-analysis.

RESULTS

Nineteen studies (n=2499 patients) were eligible. The pooled sensitivity and specificity estimates for CRP, FC, and SL were 0.49 (95% confidence interval (CI) 0.34-0.64) and 0.92 (95% CI 0.72-0.96), 0.88 (95% CI 0.84-0.90) and 0.73 (95% CI 0.66-0.79), and 0.82 (95% CI 0.73-0.88) and 0.79 (95% CI 0.62-0.89), respectively. FC was more sensitive than CRP in both diseases and was more sensitive in ulcerative colitis than Crohn's disease.

CONCLUSIONS

Although CRP, FC, and SL are useful biomarkers, their value in managing individual patients must be considered in specific clinical contexts.

Measurement of fecal calprotectin improves monitoring and detection of recurrence of Crohn's disease after surgery

BACKGROUND & AIMS

Crohn's disease (CD) usually recurs after intestinal resection; postoperative endoscopic monitoring and tailored treatment can reduce the chance of recurrence. We investigated whether monitoring levels of fecal calprotectin (FC) can substitute for endoscopic analysis of the mucosa.

METHODS

We analyzed data collected from 135 participants in a prospective, randomized, controlled trial, performed at 17 hospitals in Australia and 1 hospital in New Zealand, that assessed the ability of endoscopic evaluations and step-up treatment to prevent CD recurrence after surgery. Levels of FC, serum levels of C-reactive protein (CRP), and Crohn's disease activity index (CDAI) scores were measured before surgery and then at 6, 12, and 18 months after resection of all macroscopic Crohn's disease. Ileocolonoscopies were performed at 6 months after surgery in 90 patients and at 18 months after surgery in all patients.

RESULTS

Levels of FC were measured in 319 samples from 135 patients. The median FC level decreased from 1347 μg/g before surgery to 166 μg/g at 6 months after surgery, but was higher in patients with disease recurrence (based on endoscopic analysis; Rutgeerts score, ≥i2) than in patients in remission (275 vs 72 μg/g, respectively; P < .001). Combined 6- and 18-month levels of FC correlated with the presence (r = 0.42; P < .001) and severity (r = 0.44; P < .001) of CD recurrence, but the CRP level and CDAI score did not. Levels of FC greater than 100 μg/g indicated endoscopic recurrence with 89% sensitivity and 58% specificity, and a negative predictive value (NPV) of 91%; this means that colonoscopy could have been avoided in 47% of patients. Six months after surgery, FC levels less than 51 μg/g in patients in endoscopic remission predicted maintenance of remission (NPV, 79%). In patients with endoscopic recurrence at 6 months who stepped-up treatment, FC levels decreased from 324 μg/g at 6 months to 180 μg/g at 12 months and 109 μg/g at 18 months.

CONCLUSIONS

In this analysis of data from a prospective clinical trial, FC measurement has sufficient sensitivity and NPV values to monitor for CD recurrence after intestinal resection. Its predictive value might be used to identify patients most likely to relapse. After treatment for recurrence, the FC level can be used to monitor response to treatment. It predicts which patients will have disease recurrence with greater accuracy than CRP level or CDAI score.

Fecal calprotectin concentrations in healthy children aged 1-18 months

Objective

Fecal calprotectin (FC) is an established biomarker of gut inflammation. The aim of this study was to evaluate FC concentrations in healthy children between 1 and 18 months of age.

Methods

Healthy children aged 1-18 months were enrolled in this study at the Department of Children's Health Care in Shanghai, China. Children’s stool samples were collected and analyzed, and FC concentration was determined using a commercially available enzyme-linked immunosorbent assay (ELISA). The children's weights and lengths were measured. Parents were asked to complete a brief questionnaire regarding several clinical and sociodemographic factors.

Results

The FC concentrations were unevenly distributed; the median FC concentration was 174.3 μg/g (range: 6.0-1097.7 μg/g) or 2.241 log10 μg/g (range: 0.775-3.041 log10 μg/g) for all 288 children. The children were divided into several age groups: 1-3 months, 3-6 months, 6-9 months, 9-12 months and 12-18 months. The median FC concentrations for these age groups were 375.2 μg/g (2.574 log10 μg/g), 217.9 μg/g (2.338 log10 μg/g), 127.7 μg/g (2.106 log10 μg/g), 96.1 μg/g (1.983 log10 μg/g) and 104.2 μg/g (2.016 log10 μg/g), respectively. A significant correlation between age and FC concentration was found (r=-0.490, p<0.001). A simple correlation analysis of weight-for-length Z-scores or weight-for-age Z-scores vs. FC concentrations showed that these variables were negatively correlated (Spearman’s rho=-0.287, p<0.001; Spearman’s rho=-0.243, p<0.001, respectively).

Conclusions

The FC levels of children aged 1-18 months exhibit a downward trend with increasing age and are greater than the normal levels observed in healthy adults. In healthy children aged <6 months, FC levels are high. In children aged 6-18 months, FC concentrations are relatively low but are still higher than those of children aged >4 years.

Fecal Calprotectin is an Accurate Tool and Correlated to Seo Index in Prediction of Relapse in Iranian Patients With Ulcerative Colitis

Background:

The natural clinical course of Ulcerative Colitis (UC) is characterized by episodes of relapse and remission. Fecal Calprotectin (FC) is a relatively new marker of intestinal inflammation and is an available, non-expensive tool for predicting relapse of quiescent UC. The Seo colitis activity index is a clinical index for assessment of the severity of UC.

Objectives:

The present study aimed to evaluate the accuracy of FC and the Seo colitis activity index and their correlation in prediction of UC exacerbation.

Patients and Methods:

In this prospective cohort study, 157 patients with clinical and endoscopic diagnosis of UC selected randomly from 1273 registered patients in Fars province’s IBD registry center in Shiraz, Iran, were followed from October 2012 to October 2013 for 12 months or shorter, if they had a relapse. Two patients left the study before completion and one patient had relapse because of discontinuation of drugs. The participants' clinical and serum factors were evaluated every three months. Furthermore, stool samples were collected at the beginning of study and every three months and FC concentration (commercially available enzyme linked immunoassay) and the Seo Index were assessed. Then univariate analysis, multiple variable logistic regression, Receiver Operating Characteristics (ROC) curve analysis, and Pearson’s correlation test (r) were used for statistical analysis of data.

Results:

According to the results, 74 patients (48.1%) relapsed during the follow-up (33 men and 41 women). Mean ± SD of FC was 862.82 ± 655.97 μg/g and 163.19 ± 215.85 μg/g in relapsing and non-relapsing patients, respectively (P < 0.001). Multiple logistic regression analysis revealed that age, number of previous relapses, FC and the Seo index were significant predictors of relapse. ROC curve analysis of FC level and Seo activity index for prediction of relapse demonstrated area under the curve of 0.882 (P < 0.001) and 0.92 1(P < 0.001), respectively. Besides, FC level of 341 μg/g was identified as the cut-off point with 11.2% and 79.7% relapse rate below and above this point, respectively. Additionally, Pearson correlation coefficient (r) between FC and the Seo index was significant in prediction of relapse (r = 0.63, P < 0.001).

Conclusions:

As a simple and noninvasive marker, FC is highly accurate and significantly correlated to the Seo activity index in prediction of relapse in the course of quiescent UC in Iranian patients.

Fecal calprotectin and the clinical activity index are both useful to monitor medical treatment in patients with ulcerative colitis

BACKGROUND

Non-invasive monitoring of inflammatory bowel disease is an unmet clinical need as patients in clinical remission may have residual mucosal inflammation preceding clinical relapse.

AIMS

We aimed to assess the value of fecal calprotectin and standardized clinical activity scoring to monitor disease activity in ulcerative colitis under medical treatment.

METHODS

Forty-one patients with ulcerative colitis were included in a prospective observational study. Medical treatment was guided by clinical judgement of treating physicians. Fecal calprotectin and the clinical activity index (CAI) were measured blinded to treating physicians every 2 months until the end of follow-up. Twenty-six patients received colonoscopy for clinical reason.

RESULTS

As defined by the CAI, patients were in clinical remission (63.4 %), having mild (26.8 %) or moderate (11.2 %) disease activity. Of those in clinical remission (CAI ≤ 4), 86.4 % showed residual endoscopic activity (Mayo Score ≥1). Calprotectin levels were higher in endoscopically active disease (779.0 vs 331.5 μg/g, P = 0.034) and calprotectin testing identified more patients with endoscopic disease activity (86.4 %) than the CAI (45.5 %, P = 0.034). Medical treatment was escalated in 90.2 % during the study. Values of the CAI and calprotectin correlated with therapy escalation (OR 3.94 and 3.22, respectively). Only for calprotectin, changes between two measurements were related to intensified medical treatment (OR 1.39).

CONCLUSION

Fecal calprotectin was similarly useful to the CAI to monitor disease activity of ulcerative colitis during medical treatment but identified endoscopic disease activity far more reliably. Changes of calprotectin values between measurements might indicate clinical relapse earlier than the CAI.

The role and utility of faecal markers in inflammatory bowel disease

Crohn's disease and ulcerative colitis are characterized by periods of symptomatic relapse and remission. Diagnosis and assessment of inflammatory bowel disease has so far been based on clinical evaluation, serum parameters, radiology and endoscopy. Faecal markers such as calprotectin or lactoferrin have emerged as new diagnostic tools to detect and monitor intestinal inflammation. This review focuses on their potential clinical applications and limitations in the management of inflammatory bowel disease.

A prospective evaluation of the predictive value of faecal calprotectin in quiescent Crohn's disease

BACKGROUND

Faecal calprotectin (FC) is a non-invasive marker of gastrointestinal inflammation.

AIM

To determine whether higher FC levels in individuals with quiescent Crohn's disease are associated with clinical relapse over the ensuing 12 months.

METHODS

A single centre prospective study was undertaken in Crohn's disease patients in clinical remission. The receiver operating characteristic (ROC) curve for the primary endpoint of clinical relapse by 12 months, based on FC at baseline, was calculated. Kaplan-Meier curves of time to relapse were based on the resulting optimal FC cutoff for predicting relapse.

RESULTS

Of 97 patients recruited, 92 were either followed up for 12 months without relapsing, or reached the primary endpoint within that period. Of these, 10 (11%) relapsed by 12 months. Median FC was lower for non-relapsers, 96 μg/g (IQR 39-237), than for relapsers, 414 μg/g (IQR 259-590), (p=0.005). The area under the ROC curve to predict relapse using FC was 77.4%. An optimal cutoff FC value of 240 μg/g to predict relapse had sensitivity of 80.0% and specificity of 74.4%. Negative predictive value was 96.8% and positive predictive value was 27.6%, FC ≥240 μg/g was associated with likelihood of relapse by 12-months 12.18 (95% CI 2.55-58.2) times higher than lower values (p=0.002).

CONCLUSIONS

In this prospective dataset, FC is a useful tool to help identify quiescent Crohn's disease patients at a low risk of relapse over the ensuing 12 months. FC of 240 μg/g was the optimal cutoff in this cohort.

Noninvasive Markers of Disease Activity in Inflammatory Bowel Disease

It is often difficult to assess disease activity in inflammatory bowel disease (IBD). Noninvasive biomarkers are a means of quantifying often nebulous symptoms without subjecting patients to endoscopy or radiation. This paper highlights markers present in feces, serum, or urine that have all been compared with the gold standard, histologic analysis of endoscopically collected specimens. Two categories of markers are featured: well-researched markers of mucosal inflammation with high sensitivity and specificity (calprotectin, lactoferrin, and S100A12) and novel promising markers, some of which are already clinically employed for reasons unrelated to IBD (interleukin [IL]-17, IL-33/ST2, adenosine deaminase, polymorphonuclear elastase, matrix metalloproteinase-9, neopterin, serum M30, and fecal immunohistochemistry). The data pertaining to the more-established markers are intended to highlight recent clinical applications for these markers (ie, assessing disease outside of the colon or in the pediatric population as well as being a cost-saving alternative to colonoscopy to screen for IBD). As there is no evidence to date that a specific marker will accurately be able to represent the entire IBD patient population, it is likely that a combination of the existing markers will be most clinically relevant to the practicing gastroenterologist attempting to evaluate disease severity in a specific patient. Familiarity with the most promising emerging markers will allow a better understanding of new studies and their impact on patient care.