Fecal calprotectin is useful in predicting disease relapse in pediatric inflammatory bowel disease

Biomarkers for Monitoring of Changes in Disease Activity in Ulcerative Colitis

BACKGROUND

In recent years, various biomarkers of ulcerative colitis (UC) have emerged; however, few studies have simultaneously examined the utility of multiple biomarkers for monitoring disease activity. Additionally, serum leucine-rich alpha-2 glycoprotein (LRG), a new biomarker, may show a blunt response to anti-TNF antibody therapy. This prospective study explored effective biomarkers that could monitor disease activity changes in patients with UC. In addition, we examined the effect of anti-TNF antibody therapy on changes in LRG.

METHODS

Blood and stool samples were collected twice from patients with UC: at baseline and at least 8 weeks later. Changes in serum LRG, interleukin (IL)-6, prealbumin (pre-Alb), high-sensitivity C-reactive protein (hs-CRP), CRP, and fecal calprotectin (FC) were measured and correlated with changes in disease activity. The relationship between anti-TNF antibody therapy and LRG levels was also examined in patients with the same disease activity.

RESULTS

Forty-eight patients with UC (96 samples) were analyzed. ΔLRG and ΔIL-6 correlated strongly with the change in the partial Mayo (pMayo) score between the two time points (ΔpMayo) (r = 0.686, 0.635, respectively). In contrast, FC and IL-6 were particularly accurate predictors of clinical remission, and their area under the curves (AUCs) were significantly higher than that of CRP (AUC: 0.81, 0.76 vs. 0.50; p = 0.001, 0.005). No association was found between the administration of anti-TNF antibody preparations and the LRG values.

CONCLUSIONS

Correlations were found between changes in UC disease activity and LRG, IL-6, pre-Alb, hs-CRP, CRP, and FC. LRG reflects disease activity during anti-TNF antibody therapy.

Early Change in Fecal Calprotectin Predicts One-Year Outcome in Children Newly Diagnosed With Ulcerative Colitis

INTRODUCTION

While fecal calprotectin (FC) is used to assess disease activity in ulcerative colitis (UC) there are little data concerning the role of serial FC levels at diagnosis in predicting clinical course. We sought to determine whether FC at diagnosis or early change following therapy predicts clinical outcomes in pediatric UC.Methods: Children with newly diagnosed UC were treated with standardized regimens of mesalamine or corticosteroids (CS). CS tapering and escalation to additional therapy or colectomy were by protocol. Patients with baseline or week 4 or week 12 FC levels were included in the analysis. Our primary outcome was CS-free remission on mesalamine at week 52. We compared the prognostic value of a baseline FC as well as a change in FC by week 4 or week 12 in predicting clinical outcomes.

RESULTS

The study included 352 children (113 initial mesalamine, 239 initial CS, mean age 12.6 years) with UC. At Week 52, 135 (38.3%), 84 (23.8%), and 19 (5.4%) children achieved CS-free remission, needed anti-tumor necrosis factor therapy or had colectomy respectively. Baseline FC was not associated with CS-free remission at week 52. However, both week 4 (odds ratio [OR] 0.95, 95% confidence interval [CI] 0.901.00) and week 12 FC levels (OR 0.91, 95% CI 0.87-0.96) were associated with outcomes, with the latter having a stronger association with CS-free remission. Patients with a >75% decrease by 12 weeks, had a 3-fold increased likelihood of CS-free remission at 1 year.

DISCUSSION

Longitudinal changes in FC may predict 1 year outcomes better than values at diagnosis in children with a new diagnosis of UC.

Point-of-care faecal calprotectin testing in patients with paediatric inflammatory bowel disease during the COVID-19 pandemic

OBJECTIVES

Following the disruption of normal paediatric inflammatory bowel disease (IBD) services during the peak of the COVID-19 pandemic, we prospectively audited the first-time use of home faecal calprotectin testing. We aimed to provide an alternative to laboratory tests and to assess the value of home testing as part of our regular services going forward.

METHODS

Home test kits as well as accompanying user instructions were made available to our patients with paediatric IBD that required faecal calprotectin test between 17 April and 12 August 2020. Once the user completed the test, results were automatically uploaded to the result portal and clinical staff were alerted. A user feedback questionnaire was sent to users that had completed the home test.

RESULTS

Of the 54 patients, 41 (76%) aged between 4.7 and 18.1 years used the home test. A total of 45 home tests were done, one of which produced an invalid result. The decision to modify management was made in 12 (29%) of the patients, while 14 (34%) had no changes made and 15 (37%) required further assessment. Twenty (48.8%) responded to the questionnaire and 85% stated that they preferred the home test to the laboratory testing method.

CONCLUSIONS

Home calprotectin tests were useful in guiding clinical management during a time when laboratory testing was less available. They may offer benefits as part of routine paediatric IBD monitoring to help target appointments and reduce unnecessary hospital attendances in the future.

The Use of Fecal Calprotectin Testing in Paediatric Disorders: A Position Paper of the European Society for Paediatric Gastroenterology and Nutrition Gastroenterology Committee

OBJECTIVES

The aim of the study was to review the evidence regarding the clinical use and value of fecal calprotectin (FC) measurements in different gastrointestinal disorders in children.

METHODS

A literature search was conducted in the PubMed, MEDLINE, EMBASE, and Cochrane databases until October 31, 2019. Subtopics were identified and each assigned to individual authors.

RESULTS

A total of 28 recommendations were voted on using the nominal voting technique. Recommendations are given related to sampling, measurement methods, and results interpretation. The 14 authors anonymously voted on each recommendation using a 9-point scale (1 strongly disagree to 9 fully agree). Consensus was considered achieved if at least 75% of the authors voted 6, 7, 8, or 9.

CONCLUSIONS

Consensus was reached for all recommendations. Limitations for the use of FC in clinical practice include variability in extraction methodology, performance of test kits as well as the need to establish local reference ranges because of the influence of individual factors, such as age, diet, microbiota, and drugs. The main utility of FC measurement at present is in the diagnosis and monitoring of inflammatory bowel disease (IBD) as well as to differentiate it from functional gastrointestinal disorders (FAPDs). FC, however, has neither utility in the diagnosis of infantile colic nor to differentiate between functional and organic constipation. A rise in FC concentration, may alert to the risk of developing necrotizing enterocolitis and help identifying gastrointestinal involvement in children with Henoch-Schönlein purpura. FC measurement is of little value in Cow's Milk Protein Allergy, coeliac disease (CD), and cystic fibrosis. FC does neither help to distinguish bacterial from viral acute gastroenteritis (AGE), nor to diagnose Helicobacter Pylori infection, small intestinal bacterial overgrowth (SIBO), acute appendicitis (AA), or intestinal polyps.

Varicella-zoster-virus vaccination of immunosuppressed children with inflammatory bowel disease or autoimmune hepatitis: A prospective observational study

BACKGROUND AND AIMS

Children with inflammatory bowel disease (IBD) and autoimmune hepatitis (AIH) receiving immunosuppressive treatment are at risk for severe varicella zoster virus (VZV)-induced disease. This study evaluated vaccination of susceptible patients with stable disease and documented immunoreactivity without interruption of their current immunosuppression (IS).

METHODS

This prospective multicentre observational study used a prevaccination checklist to select patients with low-intensity and high-intensity IS for VZV vaccination. Tolerability and safety after immunization were assessed by questionnaire. The immune response was measured by the VZV-IgG concentration, relative avidity index (RAI), and specific lymphocyte proliferative response.

RESULTS

A total of 29 VZV vaccinations were performed in 17 seronegative patients aged 3-16 years (IBD n = 15, AIH n = 2). Eight patients received high-intensity immunosuppression, another six low-intensity immunosuppression, and three patients interrupted IS before VZV vaccination. All 29 vaccinations were well tolerated; only minor side effects such as fever and abdominal pain, were reported in two patients. One patient experienced a flare of Crohn's disease the day after vaccination. The VZV-IgG-concentration increased significantly (p = 0.018) after vaccination, and a specific lymphocyte response towards VZV in vitro was detected in all tested patients which correlated with the RAI (r = 0.489; p = 0.078).

CONCLUSIONS

VZV vaccination was well tolerated, safe and immunogenic in children receiving ongoing IS due to IBD and AIH. Ensuring immunoreactivity by clinical and laboratory parameters, rather than the type and dosage of IS, is a reasonable approach to decide on live-attenuated virus vaccinations in immunosuppressed children (German clinical trials DRKS00016357).

Clinical Spectrum in a Cohort of Patients With High Fecal Calprotectin Levels

INTRODUCTION

Distinguishing between inflammatory bowel disease (IBD) and functional gastrointestinal disorders is a diagnostic challenge. The need for non-invasive biomarker as a diagnostic tool in the assessment of gastrointestinal symptoms is required. The objectives of current study were to determine the spectrum of clinical features in patients tested for fecal calprotectin presenting with high levels and to compare calprotectin levels among already diagnosed patients known to have IBD as per biopsy findings and documented on patients' file with newly presenting patients who were being investigated and did not have a diagnosis.

METHODS

This retrospective cross-sectional study was conducted in the Department of Pathology and Laboratory Medicine and Department of Medicine, Aga Khan University, Karachi, Pakistan from January 2017 to December 2019. Subjects tested for fecal calprotectin who had elevated fecal calprotectin levels (n = 150) were included in the current study. Each patient deposited a random stool sample in an airtight container for calprotectin analysis. Biochemical analysis of calprotectin was performed by enzyme-linked immunosorbent assay using epitope calprotectin test kit (Epitope Diagnostics, Italy) on ETI-Max 3000 immunoassay analyzer (DiaSorin, Italy). A structured history form was used for data collection.  Results: One hundred and fifty patients were available for inclusion in the final analysis. Majority of the patients (n = 117, 78%) were adults (>18 years of age), and 52.7% (n = 79) were females. Median fecal calprotectin (IQR) was 317.3 μg/g (549.10 - 239.2 μg/g) in children (n = 33) and 305 μg/g (609.9 - 201.6 μg/g) in adults; the difference was statistically non-significant (p value > 0.05). On categorization according to disease, fecal calprotectin levels were significantly elevated (p value = 0.033) in IBD patients compared to normal subjects, 644 μg/g (644 - 587.8 μg/g) vs 308.5 μg/g (505.4 - 233.8 μg/g), respectively. Diarrhea (n = 13, 38.4%), abdominal cramps (n = 12, 36.4%), and weight loss (n = 11, 33.3%) were the most common complaints noted in children with high fecal calprotectin levels, whereas in adults, abdominal cramps (n = 60, 51.3%), diarrhea (n = 59, 50.4%), and weight loss (n = 46, 39.3%) were the common complaints. The median fecal calprotectin levels in children already known to have IBD (n = 3) were higher than the levels noted in children with no diagnosis (n = 30); p value > 0.05. Similarly, median fecal calprotectin levels in adults with IBD (n = 28) were higher than the levels noted in patients with no specific diagnosis (n = 91), 400.7 μg/g (656.6 - 244.3 μg/g) vs 302.7 μg/g (564.6 - 206 μg/g); p value > 0.05.

CONCLUSION

Current study affirms that the fecal calprotectin test can be used in identifying IBD patients in all age groups.

Correlation between biomarkers (calprotectin, seromucoid, metalloproteinase-3 and CRP) and clinical and endoscopic activity of ulcerative colitis in children

PURPOSE

The aim of the study was to compare the clinical activity and inflammatory markers with the endoscopic activity of ulcerative colitis (UC) and mucosal healing.

PATIENTS AND METHODS

The study included 50 children aged 2-18 years (27 girls, 23 boys) diagnosed with UC at various stages of the disease; 8 children were assessed twice. In 20 children, colonoscopy revealed pancolitis, in 24 - left-sided colitis, and in 6 - ulcerative proctitis. The clinical activity of UC was assessed according to the Pediatric Ulcerative Colitis Activity Index (PUCAI). Endoscopic index of the colon inflammation was assessed according to the Rachmilewitz scoring. We assessed the clinical activity of UC, the concentration of fecal calprotectin (FC), seromucoid, metalloproteinase-3 (MMP-3) and C-reactive protein (CRP).

RESULTS

The study demonstrated significant decrease in the clinical activity, FC, seromucoid and MMP-3 in endoscopic remission. We found a strong positive correlation between PUCAI, FC, serum seromucoid and serum MMP-3 with the endoscopic activity. However, we found no relationship between the concentration of CRP and the endoscopic activity of the disease. Among the studied markers, seromucoid exhibited the best performance in distinguishing between patients with endoscopic remission and endoscopically active disease.

CONCLUSIONS

The examined inflammatory markers such as FC, as well as serum seromucoid and MMP-3 levels may be helpful in the assessment of large intestine mucosal healing.

Faecal calprotectin in inflammatory bowel diseases: a review focused on meta-analyses and routine usage limitations

A growing body of evidence has been published about the usefulness of measuring calprotectin in faecal samples (FCAL) in inflammatory bowel disease (IBD) assessment, including diagnosis, monitoring of disease activity and relapse prediction. Several systematic reviews with meta-analyses compiling studies for each particular clinical setting have been carried out in recent years. Most of these were focused on the use of FCAL in IBD diagnosis and showed a relevant role for this marker in selecting patients with gastrointestinal symptoms who would not need a further examination by endoscopy. Although a lesser number of meta-analyses have been performed on the use of FCAL as a surrogate marker of disease activity, a close correlation between FCAL and endoscopic activity of IBD has been shown. With respect to the predictive capacity of FCAL for IBD relapse, a single meta-analysis published indicates that this role is more limited. Furthermore, FCAL thresholds vary considerably depending on the clinical setting and, what is more concerning, among different commercially available assays due to a lack of FCAL concentration interchangeability. Here, we summarise recent publications about the role and limitations of FCAL in IBD, with a special focus on meta-analyses, and give an overview of alternative faecal biomarkers.

Prediction of treatment outcome and relapse in inflammatory bowel disease

Prediction of treatment outcome and clinical relapse in patients with inflammatory bowel disease (IBD), either ulcerative colitis (UC) or Crohn's disease (CD), is particularly important because therapeutics for IBD are not always effective and patients in remission could frequently relapse. Because undergoing endoscopy for the purpose is sometimes invasive and burdensome to patients, the performance of surrogate biomarkers has been investigated. Areas covered: We particularly featured the performance of patient symptoms, blood markers including C-reactive protein (CRP), fecal markers including fecal calprotectin (Fcal) and fecal immunochemical test (FIT) for prediction of endoscopic mucosal healing (MH) and prediction of relapse. Studies of other modalities and therapeutic drug monitoring (TDM) have also been explored. Expert opinion: Meticulous evaluation of patient symptoms could be predictive for MH in UC. CRP and Fcal may be accurate in prediction of MH of CD when MH is evaluated throughout the entire intestine including the small bowel. Repeated measurements of fecal markers including Fcal and FIT in patients with clinical remission would raise predictability of relapse. Prediction of treatment outcome by monitoring with blood markers including CRP, fecal markers including Fcal, and TDM has frequently been performed in recent clinical trials and shown to be effective.

Systematic Review with Meta-Analysis: Fecal Calprotectin as a Surrogate Marker for Predicting Relapse in Adults with Ulcerative Colitis

The clinical course of ulcerative colitis (UC) is featured by remission and relapse, which remains unpredictable. Recent studies revealed that fecal calprotectin (FC) could predict clinical relapse for UC patients in remission, which has not yet been well accepted. To detect the predictive value of FC for clinical relapse in adult UC patients based on updated literature, we carried out a comprehensive electronic search of PubMed, Web of Science, Embase, and the Cochrane Library to identify all eligible studies. Diagnostic accuracy including pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and pooled area under the receiver operating characteristic (AUROC) was calculated using a random effects model. Heterogeneity across studies was assessed by the I 2 metric. Sources of heterogeneity were detected using subgroup analysis. Metaregression was used to test potential factors correlated to DOR. Publication bias was assessed using Deek's funnel plots. In our study, 14 articles enrolling a total of 1110 participants were finally included, and all articles underwent a quality assessment. Pooled sensitivity, specificity, PLR, and NLR with 95% confidence intervals (CIs) were 0.75 (95% CI: 0.70-0.79), 0.77 (95% CI: 0.74-0.80), 3.45 (95% CI: 2.31-5.14), and 0.37 (95% CI: 0.28-0.49) respectively. The area under the summary receiver operating characteristic (sROC) curve was 0.82, and the diagnostic odds ratio was 10.54 (95% CI: 6.16-18.02). Our study suggested that FC is useful in predicting clinical relapse for adult UC patients in remission as a simple and noninvasive marker.

Mucosal Profiles of Immune Molecules Related to T Helper and Regulatory T Cells Predict Future Relapse in Patients With Quiescent Ulcerative Colitis

BACKGROUND

T helper (Th)- and regulatory T (Treg) cell-related immune molecules are implicated in ulcerative colitis (UC). However, the association between their mucosal expression during remission and the subsequent clinical course of UC is unknown.

METHODS

The expression of cytokines and transcription factors related to Th1, Th2, Th17, and Treg in endoscopic mucosal biopsy specimens from 40 UC patients in clinical remission and 9 controls was measured by quantitative polymerase chain reaction. The relationship between their expression patterns, as stratified by Mayo Endoscopic Subscore (MES), and any future relapse was evaluated by univariate and multivariate analyses.

RESULTS

Six of 40 patients (baseline MES 0/1/2, 22/14/4) experienced a relapse during the study period (median, 37 months). At baseline, even in the MES0 patients, the interleukin (IL)-17A of the patients was significantly upregulated in comparison with controls (P = 0.0351). Future relapse was associated with a higher baseline expression of IL-17A, IL-17F, and IL-21 in MES0/1, and the upregulation of IL-17F and IL-21 remained statistically significant when limited to MES0 patients. Kaplan-Meier analysis revealed that as a single marker, a higher IL-21 level best grouped patients with an increased risk of relapse (P = 0.0042). Furthermore, a multivariate model that consisted of IL-21 and T-bet showed an even greater value (P = 0.0001).

CONCLUSIONS

The profiles of Th/Treg-related gene expression in the colonic mucosa are altered, even during clinical and endoscopic remission of UC, with a detectable Th17-predominant profile predicting future relapse. This association might represent latent immune dysregulation during disease quiescence and has the potential to be utilized to improve patient care.

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.

Fecal calprotectin is not superior to serum C-reactive protein or the Harvey-Bradshaw index in predicting postoperative endoscopic recurrence in Crohn's disease

BACKGROUND

Fecal calprotectin (FC) is a widely used noninvasive marker of gut inflammation that is associated with endoscopic severity in Crohn's disease (CD). However, FC has been inconsistent in predicting postoperative recurrence of CD, and its utility in the postoperative setting remains unclear.

MATERIALS AND METHODS

Blood and fecal samples were collected in consecutively recruited patients with CD who had undergone ileocolonic resection and required a colonoscopy to assess postoperative recurrence, as defined by the Rutgeerts score (RS).

RESULTS

A total of 86 patients were prospectively recruited at five centers. Overall, 49 (57%) had CD recurrence (RS≥i2). FC concentrations trended to increase with RS severity; FC median (interquartile range) was significantly higher in patients with endoscopic recurrence than those in endoscopic remission [172.5 (75-375) vs. 75 (36.5-180.5) μg/g, respectively]. The same occurred for C-reactive protein (CRP) [0.5 (0.1-0.95) vs. 0.1 (0.02-0.27)] mg/dl and the Harvey-Bradshaw index (HBI) [4 (2-7) vs. 1 (0-3.5)]. The three variables significantly correlated. The area under the curve to discriminate between patients in endoscopic remission and recurrence was 0.698 for FC, with 62 μg/g being the optimal cut-off point. This indicated FC would have 85.7% sensitivity and 45.9% specificity in detecting any recurrence, having positive predictive value and negative predictive value of 67.7 and 70.8%, respectively. Area under the curve for CRP and HBI were both 0.710. The combination of CRP and HBI provided a positive predictive value 95.7 and a diagnostic odds ratio of 30.8.

CONCLUSION

FC is not better than CRP combined with HBI to predict endoscopic postoperative recurrence of CD.

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.

Accuracy of Consecutive Fecal Calprotectin Measurements to Predict Relapse in Inflammatory Bowel Disease Patients Under Maintenance With Anti-TNF Therapy: A Prospective Longitudinal Cohort Study

BACKGROUND AND GOAL

Predicting relapse in inflammatory bowel disease (IBD) patients could allow early changes in therapy. We aimed at evaluating the accuracy of consecutive fecal calprotectin (FC) measurements to predict flares in IBD patients under maintenance treatment with anti-tumor necrosis factor (TNF) drugs.

STUDY

A prospective longitudinal cohort study with 16-month follow-up period was designed. IBD patients in clinical remission for at least 6 months under anti-TNF therapy were included. FC was quantified at 4-month intervals for 1 year, and patients were clinically evaluated for relapse at 2-month intervals. Diagnostic accuracy of FC for predicting relapse was evaluated by receiver-operating characteristic curve analysis.

RESULTS

In total, 95 of 106 included patients finalized the study and were analyzed (median age 44 y, 50.5% female, 75% with Crohn's disease). A total of 30 patients (31.6%) had a relapse over follow-up. FC concentration was significantly higher in patients who relapsed (477 μg/g) than in patients who maintained in remission (65 μg/g) (P<0.005). The optimal cutoff to predict remission was 130 μg/g (negative predictive value of 100%), and 300 μg/g to predict relapse (positive predictive value of 78.3%).

CONCLUSIONS

FC is a good predictor of clinical relapse and a particularly good predictor of remission over the following 4 months in patients with IBD on maintenance therapy with anti-TNF drugs. FC levels <130 μg/g is consistently associated with maintained disease remission, whereas concentrations >300 μg/g allow predicting relapse with a high probability at any time over the following 4 months.

NLRX1 Modulates Immunometabolic Mechanisms Controlling the Host-Gut Microbiota Interactions during Inflammatory Bowel Disease

Interactions among the gut microbiome, dysregulated immune responses, and genetic factors contribute to the pathogenesis of inflammatory bowel disease (IBD). Nlrx1^−/− mice have exacerbated disease severity, colonic lesions, and increased inflammatory markers. Global transcriptomic analyses demonstrate enhanced mucosal antimicrobial defense response, chemokine and cytokine expression, and epithelial cell metabolism in colitic Nlrx1^−/− mice compared to wild-type (WT) mice. Cell-specificity studies using cre-lox mice demonstrate that the loss of NLRX1 in intestinal epithelial cells (IEC) recapitulate the increased sensitivity to DSS colitis observed in whole body Nlrx1^−/− mice. Further, organoid cultures of Nlrx1^−/− and WT epithelial cells confirm the altered patterns of proliferation, amino acid metabolism, and tight junction expression. These differences in IEC behavior can impact the composition of the microbiome. Microbiome analyses demonstrate that colitogenic bacterial taxa such as Veillonella and Clostridiales are increased in abundance in Nlrx1^−/− mice and in WT mice co-housed with Nlrx1^−/− mice. The transfer of an Nlrx1^−/−-associated gut microbiome through co-housing worsens disease in WT mice confirming the contributions of the microbiome to the Nlrx1^−/− phenotype. To validate NLRX1 effects on IEC metabolism mediate gut–microbiome interactions, restoration of WT glutamine metabolic profiles through either exogenous glutamine supplementation or administration of 6-diazo-5-oxo-l-norleucine abrogates differences in inflammation, microbiome, and overall disease severity in Nlrx1^−/− mice. The influence NLRX1 deficiency on SIRT1-mediated effects is identified to be an upstream controller of the Nlrx1^−/− phenotype in intestinal epithelial cell function and metabolism. The altered IEC function and metabolisms leads to changes in barrier permeability and microbiome interactions, in turn, promoting greater translocation and inflammation and resulting in an increased disease severity. In conclusion, NLRX1 is an immunoregulatory molecule and a candidate modulator of the interplay between mucosal inflammation, metabolism, and the gut microbiome during IBD.

Role of capsule endoscopy and fecal biomarkers in small-bowel Crohn's disease to assess remission and predict relapse

BACKGROUND AND AIMS

Capsule endoscopy (CE) is the most sensitive test to diagnose small-bowel Crohn's disease (CD). Conventional parameters poorly assess CD remission, and although fecal biomarkers assess colonic activity, their role in assessing remission is uncertain. We report CE findings in small-bowel CD patients in clinical remission compared with fecal biomarkers and standard clinical tools to determine mucosal remission and predict relapses.

METHODS

Forty-three adult small-bowel CD patients in clinical remission (Crohn's Disease Activity Index [CDAI] <150) were prospectively enrolled at 4 academic centers and followed clinically for 12 months. Baseline CE studies were scored using the Capsule Endoscopy Scoring Index (CESI or Lewis score). Baseline and endpoint fecal biomarkers were assayed.

RESULTS

CE findings were normal in 17 patients (40%), mild inflammation in 19 (44%), and moderate to severe inflammation in 7 (16%). Of the 26 patients (60%) with mucosal inflammation on CE, 85% had elevated baseline fecal calprotectin and 77% elevated lactoferrin level. Calprotectin and lactoferrin were normal in all patients without inflammation and elevated in all with moderate to severe inflammation. CESI correlated significantly with calprotectin, lactoferrin, and S100A12 levels but not either CDAI or C-reactive protein. During follow-up, 14% of patients exhibited a clinical flare; all had mucosal inflammation at CE and 83% had elevated baseline calprotectin and lactoferrin levels.

CONCLUSIONS

In small-bowel CD patients in clinical remission, many had ongoing mucosal inflammation assessed by CE and fecal biomarkers. Only some developed a clinical flare during medium-term follow-up. These findings suggest CE and fecal biomarkers are useful in monitoring small-bowel CD progress.

Fecal calprotectin measurement is a marker of short-term clinical outcome and presence of mucosal healing in patients with inflammatory bowel disease

AIM

To evaluate the utility of fecal calprotectin (FC) in predicting relapse and endoscopic activity during follow-up in an inflammatory bowel disease (IBD) cohort.

METHODS

All FC measurements that were obtained during a 3-year period from patients with inflammatory bowel disease in clinical remission were identified. Data regarding the short-term (6 mo) course of the disease were extracted from the medical files. Exclusion criteria were defined as: (1) An established flare of the disease at the time of FC measurement, (2) Loss to follow up within 6 mo from baseline FC measurement, and, (3) Insufficient data on file. Statistical analysis was performed to evaluate whether baseline FC measurement could predict the short term clinical relapse and/or the presence of mucosal healing.

RESULTS

We included 149 [Crohn’s disease (CD) = 113, Ulcerative colitis (UC) = 36, male = 77] IBD patients in our study. Within the determined 6-month period post-FC measurement, 47 (31.5%) had a disease flare. Among 76 patients who underwent endoscopy, 39 (51.3%) had mucosal healing. Baseline FC concentrations were significantly higher in those who had clinical relapse compared to those who remained in remission during follow up (481.0 μg/g, 286.0-600.0 vs 89.0, 36.0-180.8, P < 0.001). The significant predictive value of baseline median with IQR FC for clinical relapse was confirmed by multivariate Cox analysis [HR for 100μg/g: 1.75 (95%CI: 1.28-2.39), P = 0.001]. Furthermore, lower FC baseline values significantly correlated to the presence of mucosal healing in endoscopy (69.0 μg/g, 30.0-128.0 vs 481.0, 278.0-600.0, in those with mucosal inflammation, median with IQR, P < 0.001). We were able to extract cut-off values for FC concentration with a high sensitivity and specificity for predicting clinical relapse (261 μg/g with AUC = 0.901, sensitivity 87.2%, specificity 85.3%, P < 0.001) or mucosal healing (174 μg/g with AUC = 0.956, sensitivity 91.9%, specificity 87.2%, P < 0.001). FC was better than CRP in predicting either outcome; nevertheless, having a pathological CRP (> 5 mg/L) in addition to the cut-offs for FC, significantly enhanced the specificity for predicting clinical relapse (95.1% from 85.3%) or endoscopic activity (100% from 87.2%).

CONCLUSION

Serial FC measurements may be useful in monitoring IBD patients in remission, as FC appears to be a reliable predictor of short-term relapse and endoscopic activity.

Monitoring and detection of disease recurrence after resection for Crohn's disease: the role of non-invasive fecal biomarkers

Ileocolonoscopy is the gold standard for the diagnosis and assessment of postoperative recurrence in Crohn's disease (CD). Nevertheless, endoscopy is time-consuming and invasive. A minimally invasive and simple screening test would improve patient adherence to examination and provide greater clinical benefit. A number of fecal biomarkers have been evaluated for their utility for the diagnosis and monitoring of inflammatory bowel disease as alternative tests to endoscopy. Area covered: In this review, we focused on the utility of fecal biomarkers in the management of postoperative CD. Our major endeavor was to present an evidence-based assessment of the results of clinical trials on the available data. A literature search was conducted using the Medline. Expert commentary: Calprotectin and lactoferrin, both neutrophil-derived proteins, are the two most frequently used fecal biomarkers in clinical trials and practice. Several studies evaluated the role of these fecal biomarkers in patients with postoperative CD. These studies suggest that fecal calprotectin, and to a lesser degree lactoferrin, are useful in assessing endoscopic severity and in predicting future clinical recurrence after resection for CD. However, large scale, well-designed studies are necessary to rigorously evaluate the role of fecal biomarkers in postoperative CD.

An update on diagnostic and prognostic biomarkers in inflammatory bowel disease

INTRODUCTION

Diagnosis of the chronic inflammatory bowel diseases relies upon initial recognition of an inflammatory condition, followed by definitive endoscopic, histological and radiological investigations. Various biomarkers are available to assist with initial elucidation of an inflammatory process: these also have important roles after diagnosis in monitoring and ongoing assessment of progress. Areas covered: Various inflammatory markers, serological tests and genetic analyses may be helpful in predicting the course of disease in the coming months. This review provides an update on the current understanding and knowledge about these markers. It also highlights key gaps and identifies aspects that require further study. Expert commentary: Our current approach to the application of non-invasive biomarkers is rudimentary. Further work is required to elucidate the roles of the various markers.

Comparison of non-invasive biomarkers faecal BAFF, calprotectin and FOBT in discriminating IBS from IBD and evaluation of intestinal inflammation

Faecal calprotectin and faecal occult blood test (FOBT) were widely used in the diagnosis and assessment of intestinal inflammation in inflammatory bowel disease (IBD). Recently we identified an excellent new biomarker B cell-activating factor (BAFF) for IBD. Here in this study we compared the efficacy of faecal BAFF, calprotectin and FOBT to find the “best non-invasive marker”. Results showed that for discriminating IBD from IBS, BAFF ≥227.3 pg/ml yield 84% sensitivity, 100% specificity, 100% positive predictive value (PPV) and 64% negative predictive value (NPV) while calprotectin ≥50 µg/g yield 76% sensitivity, 93% specificity, 97% PPV and 53% NPV. FOBT yield 65% sensitivity, 93% specificity, 97% PPV and 43% NPV. Combining BAFF with calprotectin tests yield 94% sensitivity, 93% specificity, 98% PPV, 81% NPV. Faecal BAFF level showed the stronger correlation with endoscopic inflammatory score as compared to calprotectin not only in UC (correlation coefficient [r] = 0.69, p < 0.0001 vs. r = 0.58, p < 0.0001), but also in CD (r = 0.58, p < 0.0001 vs. r = 0.52, p = 0.0003). Our results indicating that faecal BAFF is a promising non-invasive biomarker in IBD differential diagnosis and monitoring of intestinal inflammation.

[Fecal Calprotectin in Inflammatory Bowel Disease]

Inflammatory bowel disease (IBD), Crohn's disease and ulcerative colitis comprise conditions characterized by chronic, relapsing immune activation and inflammation within the gastrointestinal tract. Objective estimation of intestinal inflammation is the mainstay in the diagnosis and observation of IBD, but is primarily dependent on expensive and invasive procedures such as endoscopy. Therefore, a simple, noninvasive, inexpensive, and accurate test would be extremely important in clinical practice. Fecal calprotectin is a calcium-containing protein released into the lumen that is excreted in feces during acute and chronic inflammation. It is well-researched, noninvasive, and has high sensitivity and specificity for identification of inflammation in IBD. This review will focus on the use of fecal calprotectin to help diagnose, monitor, and determine treatment in IBD.

Raised faecal calprotectin is associated with subsequent symptomatic relapse, in children and adolescents with inflammatory bowel disease in clinical remission

BACKGROUND

Reliable data on inflammatory biomarkers for predicting relapse of paediatric inflammatory bowel disease (IBD) are lacking.

AIM

To investigate the predictive value of faecal calprotectin (FC) and CRP for symptomatic relapse in pediatric IBD in clinical remission.

METHODS

In this cross-sectional cohort study, patients <18 years with Crohn's disease or ulcerative colitis in clinical remission ≥3 months were included. At baseline, clinical and biochemical disease activity were assessed using the abbreviated-Pediatric Crohn's Disease Activity Index or Pediatric Ulcerative Colitis Activity Index, and FC and CRP respectively. Disease course over the subsequent 12 months was retrospectively assessed.

RESULTS

In total, 114 patients (56% males; median age 14.9 years) were included. Baseline FC was higher in patients that developed symptomatic relapse [median (IQR), relapse 370 μg/g (86-1100) vs. remission 122 μg/g (40-344), P = 0.003]. Baseline FC was predictive of symptomatic relapse within 6 months [HR per 250 μg/g (95% CI): 1.46 (1.21-1.77), P < 0.001], with good predictive accuracy (AUC: 0.82). Optimal FC cut-off was 350 μg/g, with positive and negative predictive value of 41% and 96%. Baseline CRP was higher in patients that developed symptomatic relapse [median (IQR), relapse 1.0 μg/g (0.6-5.0) vs. remission 1.0 μg/g (0.4-2.0), P = 0.033]. Baseline CRP was predictive of symptomatic relapse within 6 months from baseline [HR per 1 mg/L (95% CI): 1.10 (1.02-1.19), P = 0.011], with fair predictive accuracy (AUC: 0.72). Optimal CRP cut-off was 1.0 mg/L, with positive and negative predictive value of 21% and 94%.

CONCLUSIONS

Faecal calprotectin and CRP are predictive of symptomatic relapse and may be valuable in management of paediatric IBD in clinical remission.

Clinical implications of assay specific differences in f-calprotectin when monitoring inflammatory bowel disease activity over time

OBJECTIVE

With several faecal calprotectin (FC) assays on the market, it has been difficult to define a uniform threshold for discriminating between remission and active disease in patients with inflammatory bowel disease (IBD). We aimed to compare the results of different FC-assays in IBD patients, followed over time.

MATERIAL AND METHODS

IBD patients provided faecal samples and reported clinical activity every third month prospectively over a two year period. FC was measured with two ELISA - (Bühlmann and Immunodiagnostik) and one automated fluoroimmunoassay (Phadia).

RESULTS

In total, 13 patients provided 91 faecal samples. The median (IQR) concentration of FC was higher at active disease than at remission for all assays: Bühlmann 845 (1061-226) μg/g versus 62 (224-39) μg/g, Phadia 369 (975-122) μg/g versus 11 (52-11) μg/g, and Immundiagnostik 135 (302-69) μg/g versus 8 (56-4) μg/g. The Bühlmann assay produced the largest absolute difference but the corresponding relative difference seemed to be more pronounced when analysed by the Phadia - (ratio of means 8.5; 95% CI 3.3-21.9) or the Immundiagnostik assay (ratio of means 7.4; 95% CI 3.1-17.6) than by the Bühlmann assay (ratio of means 5.3; 95% CI 2.7-10.6). Consequently, the specificity for discriminating active disease from remission varied between assays (34-75%) when the cut-off 50 μg/g was used, whereas the differences in sensitivity were less pronounced.

CONCLUSIONS

Cross-comparisons revealed overall poor agreement between the assays as well as differences in the dynamics of FC. These findings suggest that standardisation of the method is needed to implement FC as a disease monitoring tool at large-scale.

Comparison of Fecal Calprotectin Methods for Predicting Relapse of Pediatric Inflammatory Bowel Disease

Background. Pediatric inflammatory bowel disease (IBD) is on the rise worldwide. Endoscopies are necessary for IBD assessment but are invasive, expensive, and inconvenient. Recently, fecal calprotectin (FCal) was proposed as a noninvasive and specific marker of gut inflammation. We evaluated the analytical performance of three FCal assays and their clinical performance in predicting relapse in pediatric IBD. Methods. This study used 40 pediatric IBD and 40 random non-IBD patients' fecal samples. Two automated ELISAs (Bühlmann and PhiCal® Calprotectin-EIA) and an EliA (Phadia 250 EliA-Calprotectin) were used to evaluate the analytical performance. The clinical performance was assessed by PhiCal Calprotectin-EIA, EliA-Calprotectin, and Bühlmann immunochromatographic point-of-care test (POCT). Results. All assays displayed acceptable analytical performance below and above the medical decision cut-off [imprecision (CV < 10% intra-assay; <15% interassay); linearity (overall mean % deviation < 16.5%)]. The agreement with PhiCal Calprotectin-EIA was 100% and 78.6% for Bühlmann (95% CI, 87.5-100; Kappa: 1) and EliA-Calprotectin (95% CI, 60.5-89.8; Kappa: 0.32), respectively, and 63.6% between Bühlmann and EliA-Calprotectin (95% CI, 46.6-77.8; Kappa: 0.16). All assays evaluated had similar clinical performance [AUC: 0.84 (EliA-Calprotectin); 0.83 (POCT and PhiCal Calprotectin-EIA)]. Conclusion. FCal levels determined using the same method and assay together with clinical history would be a noninvasive and useful tool in monitoring pediatric IBD.

Calprotectin: Clinical Applications in Pediatrics

As seen over the past 20 years, calprotectin has evolved as a novel, non-invasive biomarker of gastrointestinal (GI) inflammation. We present this review of calprotectin in pediatrics. This article will focus on studies using calprotectin concentrations from different body fluids to monitor inflammation in different disease states and conditions. The ultimate goal of our group is to lay down a foundation as we consider using calprotectin prospectively as a marker of intestinal inflammation that could lead to further testing and possibly a marker of preparedness for feeding. We surveyed all published studies in English of calprotectin in neonates, infants, children, and adolescents through February 2014. We will discuss calprotectin's basic properties and analysis such as characteristics, identification, presence in body fluids, and maturational development. In addition, calprotectin's use in inflammatory diseases exploring both GI and non-GI conditions will be evaluated and compared with other serum markers presently available. Finally, a summary of our findings and discussion of future work that could be undertaken in order to render calprotectin as a more useful monitoring tool to the medical research community will complete the review.

Utility of surrogate markers for the prediction of relapses in inflammatory bowel diseases

Patients with diagnosed inflammatory bowel disease (IBD) will commonly experience a clinical relapse in spite of a prolonged therapy-induced period of clinical remission. The current methods of assessing subclinical levels of low-grade inflammation which predispose patients to relapse are not optimal when considering both cost and patient comfort. Over the past few decades, much investigation has discovered that proteins such as calprotectin that are released from inflammatory cells are capable of indicating disease activity. Along with C-reactive protein and erythrocyte sedimentation rate, calprotectin has now become part of the current methodology for assessing IBD activity. More recently, research has identified that other fecal and serum biomarkers such as lactoferrin, S100A12, GM-CSF autoantibodies, α1-antitrypsin, eosinophil-derived proteins, and cytokine concentrations have variable degrees of utility in monitoring gastrointestinal tract inflammation. In order to provide direction toward novel methods of predicting relapse in IBD, we provide an up-to-date review of these biomarkers and their potential utility in the prediction of clinical relapse, given their observed activities during various stages of clinical remission.

How to use faecal calprotectin in management of paediatric inflammatory bowel disease

Faecal calprotectin (FC) is a neutrophil-derived protein released in stool in response to mucosal inflammation. It is a simple, cheap and non-invasive test with high sensitivity and moderate specificity, which can be useful in the diagnosis and monitoring of inflammatory bowel disease (IBD). FC levels correlate well with bowel inflammation (both macroscopic and histological activity) and are not influenced by disease location or type of IBD. Despite the shortcoming with regards to specificity, it is the high sensitivity of FC that makes it a valuable screening tool in the diagnosis of IBD. It is especially effective in identifying children with low probability of IBD who would not benefit from further investigations. The cut-off value selected has a significant impact on the diagnostic accuracy of the test, influencing its sensitivity and specificity, and must be interpreted judiciously. Its role in disease monitoring is as an add-on test to Paediatric Ulcerative Colitis Activity Index and Paediatric Crohn's Disease Activity Index scores and can be used to differentiate disease relapse from functional symptoms. High levels of FC are also seen in a number of other conditions, such as gastrointestinal infections and coeliac disease. It is recommended that infective causes affecting the gut must be excluded first, before FC is measured.

Fecal calprotectin: its scope and utility in the management of inflammatory bowel disease

Gastrointestinal symptoms such as abdominal pain, dyspepsia, and diarrhea are relatively nonspecific and a common cause for seeking medical attention. To date, it is challenging for physicians to differentiate between functional and organic gastrointestinal conditions and it involves the use of serological and endoscopic techniques. Therefore, a simple, noninvasive, inexpensive, and effective test would be of utmost importance in clinical practice. Fecal calprotectin (FC) is considered to be a reliable biomarker that fulfills these criteria. FC can detect intestinal inflammation, and its level correlates well with macroscopic and histological inflammation as detected by colonoscopy and biopsies, respectively. FC has a decent diagnostic accuracy for differentiating organic diseases and functional disorders because of its excellent negative predictive value in ruling out inflammatory bowel disease (IBD) in symptomatic undiagnosed patients. There is accumulating evidence that FC has been effectively used to monitor the natural course of IBD, to predict relapse, and to see the response to treatment. This novel biomarker has the ability to assess mucosal healing (MH), which is a therapeutic goal in IBD management. A literature search was carried out using PubMed with the keywords FC, IBD, intestinal inflammation, and MH. In our review, we provide an overview of the utility and scope of FC as a biomarker in patients with IBD as well as undiagnosed patients with lower gastrointestinal symptoms.

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.

Role of fecal calprotectin in evaluation of disease activity and recurrence of ulcerative colitis

AIM: To assess the potential role of calprotectin (CP) in the evaluation of ulcerative colitis (UC) severity and recurrence.

METHODS: Fecal samples were collected from 72 patients with active UC (A-UC), 28 patients with UC in remission (R-UC) and 18 healthy controls. The levels of CP in fecal samples were analyzed by ELISA. The potential role of CP in the evaluation of disease severity, efficacy of clinical treatment and prognosis was investigated.

RESULTS: The levels of fecal CP were markedly increased in patients with A-UC (373.2 µg/g ± 89.8 µg/g) compared with those in R-UC patients (78.6 µg/g ± 24.3 µg/g) and healthy controls (46.9 µg/g ± 15.3 µg/g) (P < 0.001). Fecal CP was found to be significantly increased in severe UC patients compared with that in mild-moderate UC patients (P < 0.01). Fecal CP had a positive correlation with Mayo scores and C-reactive protein in the sera of UC patients (P < 0.01). CP was found to be significantly decreased in UC patients after receiving effective treatment compared with that before treatment (P < 0.001). However, it was observed to be markedly increased in UC patients with disease recurrence (P < 0.001).

CONCLUSION: These data suggest that fecal CP is significantly increased in active UC patients, which can be used to diagnose the disease and predict the disease progression. Therefore, fecal CP is a useful biological marker for the prediction of UC development.

Fecal Calprotectin as Predictor of Relapse in Patients With Inflammatory Bowel Disease Under Maintenance Infliximab Therapy

BACKGROUND AND GOALS

Predicting relapse in Inflammatory Bowel Disease (IBD) could allow for early changes of treatment. Close monitoring of fecal calprotectin (FC) could be useful to predict relapse in IBD. Aim of the study was to evaluate the predictive value of a rapid FC test to predict flares in patients with IBD under maintenance therapy with Infliximab.

STUDY

A prospective observational cohort study was designed. IBD patients in clinical remission under maintenance Infliximab therapy were included. FC was measured using a rapid test on a stool sample obtained within 24 hours before Infliximab infusion. Clinical examination was performed 2 months after that infusion.

RESULTS

Fifty-three patients were included (52.8% female). Thirty-three patients (62.3%) had Crohn's disease and 20 (37.7%) had ulcerative colitis. All patients were in remission at inclusion. After 2 months, 41 patients (77.4%) remained in clinical remission and 12 (22.6%) presented a relapse. FC (mean±SD) in relapsing and not-relapsing disease was 332±168 and 110±163 µg/g, respectively (P<0.005). A FC concentration>160 µg/g had a sensitivity of 91.7%, and specificity of 82.9% to predict relapse.

CONCLUSIONS

In IBD patients under Infliximab maintenance therapy, high FC levels allow predicting relapse within the following 2 months. Long-term remission is associated with low calprotectin levels. Further studies are required to confirm these results.

Fecal calprotectin in inflammatory bowel disease

Inflammatory bowel disease (IBD) and irritable bowel syndrome share many symptoms. While irritable bowel syndrome is a functional bowel disorder for which no specific treatment is available, the range of effective therapies for IBD is evolving rapidly. Accurate diagnosis of IBD is therefore essential. Clinical assessment, together with various imaging modalities and endoscopy, has been the mainstay of diagnosis for many years. Fecal biomarkers of gastrointestinal inflammation have appeared in the past decade, of which calprotectin, a neutrophil cytosolic protein, has been studied the most. Crohn’s disease and ulcerative colitis are chronic remitting and relapsing diseases, and objective assessment of disease activity and response to treatment are important. This review focuses on the use of fecal calprotectin measurements in the diagnosis and monitoring of patients with IBD.

How to predict clinical relapse in inflammatory bowel disease patients

Inflammatory bowel diseases have a natural course characterized by alternating periods of remission and relapse. Disease flares occur in a random way and are currently unpredictable for the most part. Predictors of benign or unfavourable clinical course are required to facilitate treatment decisions and to avoid overtreatment. The present article provides a literature review of the current evidence on the main clinical, genetic, endoscopic, histologic, serologic and fecal markers to predict aggressiveness of inflammatory bowel disease and discuss their prognostic role, both in Crohn’s disease and ulcerative colitis. No single marker seems to be reliable alone as a flare predictor, even in light of promising evidence regarding the role of fecal markers, in particular fecal calprotectin, which has reported good results recently. In order to improve our daily clinical practice, validated prognostic scores should be elaborated, integrating clinical and biological markers of prognosis. Finally, we propose an algorithm considering clinical history and biological markers to intercept patients with high risk of clinical relapse.

Clinical application of faecal calprotectin in ulcerative colitis patients

OBJECTIVE

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

PATIENTS AND METHODS

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

RESULTS

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

CONCLUSION

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

Disease monitoring in inflammatory bowel disease

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

Biomarkers of Inflammation in Inflammatory Bowel Disease

Recent observations suggest that subjective measures of disease activity in inflammatory bowel disease (IBD) are often misleading. Objective measures of inflammation are more closely associated with important long-term outcomes, but often depend upon invasive and costly procedures such as ileocolonoscopy and cross-sectional imaging by computed tomography or magnetic resonance imaging. Noninvasive, accurate, and inexpensive measures of intestinal inflammation would allow clinicians to adopt widely the paradigm of adjusting therapies with a goal of controlling inflammation. Blood, stool, and urine markers have all been explored as indicators of intestinal inflammation in IBD, and although none has been universally adopted, some have been well-characterized, and others hold great promise. Serum C-reactive protein and fecal calprotectin are among the best-studied noninvasive biomarkers of inflammation in IBD, and their test characteristics have been described in the setting of differentiating IBD from irritable bowel syndrome, for grading inflammation, to describe the response to therapy, and in demonstrating recurrent inflammation after medical or surgically induced remission. High-throughput research platforms, including gene expression arrays, metabolomics and proteomics, are also being applied to the discovery of novel biomarkers of inflammation. It is certain that biomarkers of inflammation will attain growing importance in the clinic as we strive for more effective and cost-effective strategies to treat patients with IBD.