Usability of a home-based test for the measurement of fecal calprotectin in asymptomatic IBD patients

Home-based fecal calprotectin utilization in a general pediatric gastroenterology clinic

OBJECTIVE

Remote investigation and monitoring have gained importance in ambulatory practice. A home-based fecal calprotectin (FC) test has been developed where the sample is processed and analyzed at home through a smartphone application. We aimed to assess the use of standard ELISA (sFC) versus home-based (hFC) FC testing in a general pediatric gastroenterology clinic.

METHODS

Ambulatory pediatric patients with hFC or sFC performed between August 2019 and November 2020 were included. Data regarding demographics, clinical characteristics, medication use, investigations, and final diagnosis, categorized as inflammatory bowel disease (IBD), functional gastrointestinal (GI) disorders, organic non-IBD (ONI) GI disorders, non-GI disorders, and undetermined after 6 months of investigation, were recorded.

RESULTS

A total of 453 FC tests from 453 unique patients were included. Of those, 249 (55%) were hFC. FC levels (median) were higher in children with IBD compared to non-IBD diagnosis (sFC 795 vs. 57 μg/g, hFC 595 vs. 47 μg/g, p < 0.001), and in ONI compared to functional GI disorders (sFC 85 vs. 54 μg/g, p = 0.003, hFC 57 vs. 40 μg/g, p < 0.001). No significant difference was observed between different ONI GI disorders or subtypes of functional disorders. Age did not significantly influence levels.

CONCLUSIONS

Overall, hFC and sFC provide similar results in the general pediatric GI ambulatory setting. FC is a sensitive but not disease-specific marker to identify patients with IBD. Values appear to be higher in ONI GI disorders over functional disorders, although cut-off values have yet to be determined.

Calprotectin: two sides of the same coin

Calprotectin (CLP) is a calcium-binding protein produced by neutrophils and monocytes in the course of inflammation. Today, the role of faecal CLP in chronic IBD is well known, but in recent years attention has shifted towards circulating CLP. In fact, this molecule can be measured in different biological fluids: blood, saliva and urine, using different analytic methods that are described in this review. Furthermore, different data confirm the relevant role of serum CLP in autoimmune diseases. In this review we will highlight the correlation between high levels of circulating CLP and specific autoantibodies of major autoimmune pathologies paving the way to the employment of CLP measurement as useful biomarker for monitoring outcome in different pathologies.

Systematic review with meta-analysis: Time to diagnosis and the impact of delayed diagnosis on clinical outcomes in inflammatory bowel disease

BACKGROUND

The impact of diagnostic delay on the clinical course of inflammatory bowel disease (IBD) remains uncertain.

AIM

To perform a systematic review of time to diagnosis and the impact of delayed diagnosis on clinical outcomes in Crohn's disease (CD) and ulcerative colitis (UC).

METHODS

We searched EMBASE and Medline from inception to 30th November 2022 for studies reporting diagnostic interval, from symptom onset to IBD diagnosis. We calculated the median, interquartile range (IQR) and pooled weighted median, of median diagnostic intervals of eligible studies. We defined delayed diagnosis as individuals above the 75th centile of longest time to diagnosis in each study. Using random effects meta-analysis, we pooled odds ratios (ORs) with 95% confidence intervals (CI) for studies reporting clinical outcomes, according to delayed diagnosis.

RESULTS

One hundred and one studies representing 112,194 patients with IBD (CD = 59,359; UC = 52,835) met inclusion criteria. The median of median times to diagnosis was 8.0 (IQR: 5.0-15.2) and 3.7 months (IQR: 2.0-6.7) in CD and UC, respectively. In high-income countries, this was 6.2 (IQR: 5.0-12.3) and 3.2 months (IQR: 2.2-5.3), compared with 11.7 (IQR: 8.3-18.0) and 7.8 months (IQR: 5.2-21.8) in low-middle-income, countries, for CD and UC respectively. The pooled weighted median was 7.0 (95% CI: 3.0-26.4) and 4.6 (95% CI: 1.0-96.0) months, for CD and UC respectively. Eleven studies, representing 6164 patients (CD = 4858; UC = 1306), were included in the meta-analysis that examined the impact of diagnostic delay on clinical outcomes. In CD, delayed diagnosis was associated with higher odds of stricturing (OR = 1.88; CI: 1.35-2.62), penetrating disease (OR = 1.64; CI: 1.21-2.20) and intestinal surgery (OR = 2.24; CI: 1.57-3.19). In UC, delayed diagnosis was associated with higher odds of colectomy (OR = 4.13; CI: 1.04-16.40).

CONCLUSION

Delayed diagnosis is associated with disease progression in CD, and intestinal surgery in both CD and UC. Strategies are needed to achieve earlier diagnosis of IBD.

MicroRNA-9a-5p-NOX4 inhibits intestinal inflammatory injury by regulating the M1 polarization of intestinal macrophages

We found that the expression of microRNA (miRNA)-9a-5p decreased in inflammatory bowel diseases (IBD; ulcerative colitis and Crohn's disease). Further, we revealed the effects and mechanisms of miRNA-9a-5p for regulating IBD progression. In C57BL/6N mice, IBD was induced with dextran sodium sulfate (DSS), and the effects of endogenous miRNA-9a-5p were mimicked/antagonized through intraperitoneal injection of miRNA-9a-5p agomir and antagomir. In animal experimentation, agomir could inhibit intestinal inflammation and tissue damage, and reduce the mucosal barrier permeability. Antagomir, on the other hand, could promote barrier damage, whose effect was associated with the M1 macrophage polarization. This study finds that miRNA-9a-5p targets NOX4 to suppress ROS production, which plays an important role in mucosal barrier damage in IBD.

Early Diagnosis, Early Stratification, and Early Intervention to Deliver Precision Medicine in IBD

Despite huge advances in understanding the molecular basis of IBD, clinical management has continued to rely on a "trial and error" approach. In addition, a therapeutic ceiling has emerged whereby even the most effective interventions are only beneficial for approximately 30% of patients. Consequently, several tools have been developed to aid stratification and guide treatment-decisions. We review the potential application for many of these precision medicine approaches, which are now almost within reach. We highlight the importance of early action (and avoiding inaction) to ensure the best outcomes for patients and how combining early action with precision tools will likely ensure the right treatment is delivered at the right time and place for each individual person living with IBD. The lack of clinical impact to date from precision medicine, despite much hype and investment, should be tempered with the knowledge that clinical translation can take a long time, and many promising breakthroughs might be ready for clinical implementation in the near future. We discuss some of the remaining challenges and barriers to overcome for clinical adoption. We also highlight that early recognition, early diagnosis, early stratification, and early intervention go hand in hand with precision medicine tools. It is the combination of these approaches that offer the greatest opportunity to finally deliver on the promise of precision medicine in IBD.

Point-of-Care Testing and Home Testing: Pragmatic Considerations for Widespread Incorporation of Stool Tests, Serum Tests, and Intestinal Ultrasound

Breaking through the biologic therapy efficacy plateau for inflammatory bowel disease requires the strategic development of personalized biomarkers in the tight control model. After risk stratification early in the disease course, targeted serial monitoring consistently to assess clinical outcomes in response to therapy allows for quick therapeutic adjustments before bowel damage can occur. Point-of-care intestinal ultrasound performed by the treating gastroenterologist is an accurate cross- sectional biomarker that monitors intestinal inflammation in real-time, enhances patient care, and increases shared understanding to help achieve common treatment goals. Combining intestinal ultrasound during a clinic visit with existing serum and stool biomarkers in a home testing setup with electronic health monitoring allows for an optimized, patient-centered personalized treatment algorithm that may improve treatment outcomes. Here, we review the current state, pragmatic considerations, and future implications of point-of-care testing and home testing for noninvasive inflammatory bowel disease monitoring in the tight control model.

Fecal Calprotectin Is a Predictor of Need for Rescue Therapy in Hospitalized Severe Colitis

BACKGROUND

Up to one-third of patients hospitalized for acute severe colitis secondary to inflammatory bowel diseases (IBD) do not adequately respond to intravenous steroids. There is an unmet need to identify a useful predictor for rescue treatment in this cohort of patients.

AIMS

The aim of this study was to assess the predictive efficacy of fecal calprotectin in identifying the need for medical or surgical therapy in patients with acute severe colitis.

METHODS

We conducted a multicenter retrospective cohort study including patients with ulcerative colitis (UC) who were hospitalized for severe exacerbation of colitis. The primary outcome was the need for in-hospital medical or surgical rescue therapy. Univariate and multivariate logistic regression was performed to identify predictors of rescue therapy.

RESULTS

Our study included 147 patients with UC. One-third (33%) required rescue therapy, and 13% underwent colectomy. Patients requiring rescue therapy had significantly higher fecal calprotectin (mean 1748 mcg/g vs 1353 mcg/g, P = .02) compared with those who did not. A fecal calprotectin >800 mcg/g independently predicted the need for inpatient medical rescue therapy (odds ratio, 2.61; 95% CI, 1.12-6.12). An admission calprotectin >800 mcg/g independently predicted surgery within 3 months (odds ratio, 2.88; 95% CI, 1.01-8.17).

CONCLUSIONS

Fecal calprotectin levels may serve as a useful noninvasive predictor of medical and surgical risk in individuals with UC presenting with acute severe colitis. This approach can facilitate earlier therapeutic interventions and improve outcomes.

Efficacy of Fecal Calprotectin Combined With Stool Hemoglobin in Differentiating Bacterial Origin in Acute Gastroenteritis

OBJECTIVES

Differentiating bacterial origin in acute gastroenteritis (AGE) is important to improve outcomes. Fecal calprotectin is a sensitive screening tool for gut mucosal inflammation. This study aimed to evaluate the diagnostic efficacy and cutoff level of fecal calprotectin in distinguishing bacterial origin in pediatric AGE.

METHODS

Patients who were diagnosed with AGE at 1 to 18 years between January 2015 and January 2020 were retrospectively analyzed. A polymerase chain reaction test was applied to stool samples to detect viruses and bacteria. The level of fecal calprotectin was determined using an enzyme-linked immunosorbent assay test.

RESULTS

Eighty patients were enrolled in this study. The most common viral pathogen was norovirus, and bacterial pathogen was Clostridium perfringens. The median fecal calprotectin level was 686 μg/g (interquartile range [IQR], 140-1192 μg/g) in all patients, 560 μg/g (IQR, 60-669 μg/g) in patients with viral pathogens, and 985 μg/g (IQR, 272-1984 μg/g) in those with bacterial pathogens (P = 0.019). The stool hemoglobin concentration (337.29 vs 84.83 ng/mL, P = 0.016) and C-reactive protein (4.06 vs 0.45 mg/dL, P = 0.082) levels were higher in patients with bacterial pathogens than in those with viral pathogens. For identifying bacterial pathogens, the area under the receiver operating characteristic curve of fecal calprotectin was 0.739 (95% confidence interval, 0.584-0.894); combination with stool hemoglobin improved diagnostic efficacy, and the area under the receiver operating characteristic curve was 0.870. The optimal cutoff values of fecal calprotectin and stool hemoglobin were 815 μg/g and 158 ng/mL, respectively.

CONCLUSIONS

The combination of stool hemoglobin and fecal calprotectin may be a useful marker for detecting bacterial etiology in pediatric AGE.

Real-life utility and diagnostic accuracy of a home-performed fecal calprotectin test to predict endoscopic activity in patients with inflammatory bowel disease under maintenance treatment with adalimumab

AIMS

The home-performed fecal calprotectin (FC) test has been proposed for the remote management of inflammatory bowel disease (IBD) patients. We present our real-world experience on the use of FC home testing in IBD patients under maintenance treatment with adalimumab.

METHODS

Consecutive IBD patients on maintenance treatment with adalimumab were studied retrospectively on the basis of prospectively recorded data. FC calprotectin home test (IBDoc, Βühlmann Laboratories AG, Schönenbuch, Switzerland) was analyzed alongside sufficient information on baseline characteristics, follow-up data and treatment modifications, as well as serum biomarkers and endoscopic assessment data on the basis of validated endoscopic scores.

RESULTS

From a total of 72 IBD patients under maintenance treatment with adalimumab, 65 (90%) showed compliance with performing the home FC test. FC values were significantly higher in patients who finally needed treatment modification (37%) compared with those who were maintained on stable treatment (63%) (761 μg/g [537-1000] vs. 108 [41-335], P < 0.0001). In the logistic regression analysis FC and erythrocyte sedimentation rate (ESR) were independently correlated with endoscopically active disease (odds ratio: 1.003; 95% confidence interval, 1.001-1.006, P < 0.01 and odds ratio: 1.058; 95% confidence interval, 1.013-1.105, P < 0.05). FC identified patients with endoscopically active disease more effectively than other biomarkers with an area under the receiver operating characteristic curve of 0.78. FC levels >413 μg/g had a sensitivity of 75% and a specificity of 76% in predicting active disease in endoscopy.

CONCLUSIONS

These first real-life results indicate that in IBD patients under maintenance treatment with adalimumab FC home test is a valuable tool with high compliance rates that performs better than the other biomarkers in predicting disease endoscopic activity.

International consensus on methodological issues in standardization of fecal calprotectin measurement in inflammatory bowel diseases

BACKGROUND

Fecal calprotectin (FC) is a non-invasive marker of gut inflammation which is frequently used to guide therapeutic decisions in patients with inflammatory bowel diseases (IBD). Each step of FC measurement can influence the results, leading to misinterpretations and potentially impacting the management of IBD patients. To date, there is high heterogeneity between FC measurements and no current method is universally accepted as a standard.

AIMS

Our aim was to provide clear position statementsabout the pre-analytical and the analytical phases of FC measurement to homogenize FC levels and to minimize variability and risk of misinterpretation through aninternational consensus.

MATERIALS & METHODS

Fourteen physicians with expertise in the field of IBD and FC from 11 countries attended a virtual international consensus meeting on July 17th, 2020. A systematic literature was conducted and the literature evidence was shared and discussedamong the participants. Statements were formulated, discussed, and voted. Statements were considered approved if all participants agreed.

RESULTS

Nine statements were formulated and approved. Based on the available evidence, quantitative tests should be preferred for measuring FC. Furthermore, FC measurement, if possible, should always be performed with the same method and factors influencing FC levels should be taken into account when interpreting the results.

DISCUSSION

FC has an increasingly important role in the management of patients with IBD. However, large multicenter studies should be conducted to define the reproducibility and to confirm the diagnostic accuracy of the available FC tests.

CONCLUSION

FC concentrations guide clinicians' treatment decisions. Our statements have a relevant impact in daily practice and could be applied in clinical trials to standardize FC measurement.

Setting up a Virtual Calprotectin Clinic in Inflammatory Bowel Diseases: Literature Review and Nancy Experience

Technological progress, including virtual clinics, web or smartphone-based applications, and assessment of fecal calprotectin (FC) at home has favored the implementation of treat to target strategies for patients with inflammatory bowel diseases (IBD). Although these innovations are promising and have been associated with a significant reduction in health costs, their application in clinical practice is limited. Here, we summarize the most recent literature on virtual clinics and available FC home tests. In addition, we report the experience of IBD patients monitored through the IBDoc^® test at the Nancy University Hospital, focusing on usability testing and patient’s satisfaction. This pilot experience shows that a virtual calprotectin clinic doubles adherence rate to FC in IBD patients. This finding is especially clinically relevant in the post-coronavirus disease 2019 (COVID-19) pandemic era, with an increasing use of e-health.

The Course of SARS-COV2 Infection Was Not Severe in a Crohn's Patient Who Administered Maintenance Anti-TNF Therapy Overlapping the Early Pre-Symptomatic Period of Infection

The Inflammatory Bowel Disease (IBD) population, which may require treatment with immunosuppressive medications, may be uniquely vulnerable to COVID-19 infection. In fact, there is some evidence these medications may inhibit the cytokine storm that is theorized to cause a rapid decline seen in COVID-19. In addition, the digestive symptoms of COVID-19 can be difficult to distinguish from the activation of IBD. We present an interesting case of a Crohn’s patient inadvertently administering anti-cytokine therapy during the pre-symptomatic period of COVID-19 infection. Immune suppression during early infection with SARS-COV2 risks a poor immune response to the virus and could theoretically result in a more severe course of infection.

Clinical Trials [and Tribulations]: The Immediate Effects of COVID-19 on IBD Clinical Research Activity in the UK

There have been immediate and profound impacts of SARS-CoV-2 and COVID-19 on health care services worldwide, with major consequences for non COVID-19 related health care. Alongside efforts to reconfigure services and enable continued delivery of safe clinical care for patients with IBD, consideration must also be given to management of IBD research activity. In many centres there has been an effective shutdown of IBD clinical trial activity as research sites have switched focus to either COVID-19 related research or clinical care only. As a result, the early termination of trial programmes, and loss of potentially effective therapeutic options for IBD, has become a real and worrying prospect. Moreover, in many countries research activity has become embedded into clinical care-with clinical trials often providing access to new therapies or strategies-which would otherwise not have been available in standard clinical pathways. This pandemic has significant implications for the design, conduct, analysis, and reporting of clinical trials in IBD. In this Viewpoint, we share our experiences from a clinical and academic perspective in the UK, highlighting the early challenges encountered, and consider implications for patients and staff at research sites, sponsors, research ethics committees, funders, and regulators. We also offer potential solutions both for now and for when we enter a recovery phase from the pandemic.

Soluble Blood Markers of Mucosal Healing in Inflammatory Bowel Disease: The Future of Noninvasive Monitoring

The traditional management of inflammatory bowel disease (IBD) based on symptom control is not considered valid anymore by most specialists in this field, and a new paradigm called "treat to target" has been introduced. This is based on the assessment of disease activity using objective measures. The identification of noninvasive biomarkers is crucial to diagnosis and monitor IBD because frequent endoscopic examinations are costly and uncomfortable for the patient. In this review, we focus on blood markers that may be able to assess mucosal healing (MH) in IBD and recent advances in this area. Introduction of commercial panel to predict MH opens the way for further developments so that colonoscopy or fecal markers may be avoided in some patients. This may also permit frequent monitoring for therapeutic response and achieve MH. It is a challenging area of research to identify a panel of biomarkers that may reflect inflammation and healing to serve as a surrogate of MH.

Diagnostic utility of fecal calprotectin in patients presenting to the emergency department with suspected acute appendicitis

BACKGROUND

Acute appendicitis (AA) is one of the most common diseases faced by the surgeon in the emergency department. In clinical practice, how to diagnose patients with AA accurately is still challenging.

METHODS

We conducted a prospective study of 84 patients who presented in the emergency department with suspected AA and measured fecal calprotectin (FC) value. The final diagnosis of AA was independently determined without reference to the test results of FC. Then, we retrospectively analyzed the FC value for identifying AA.

RESULTS

FC value in patients with AA were significantly higher than that in patients without AA (240.5 vs. 68.5 ug/g, P < 0.001). Receiver-operating characteristic analyses demonstrated FC value to be highly sensitive and specific for the diagnosis of AA, as indicated by an overall area under the curve (AUC) of 0.928 (500 times of boot strap estimated 95% CI, 0.855-0.972), with an optimal cut off point of 106 ug/g. FC levels in 26 patients with simple AA were significantly lower than it in the 14 patients with suppurative AA (206 vs. 304ug/g, P = 0.001).

CONCLUSIONS

FC test provides a sensitive, convenient and economical method to help facilitate the diagnosis of AA in emergency department. Especially for hospitals without computed tomography equipment or patients who are not suitable to exposed to radiation, FC test is of great significance for improving the diagnostic accuracy of AA.

The Accuracy of a Home-performed Faecal Calprotectin Test in Paediatric Patients With Inflammatory Bowel Disease

OBJECTIVES

Owing to the invasiveness of endoscopy, the use of biomarkers, especially faecal calprotectin (FC), has become standard for remission assessment. This study aimed to compare the accuracy for detection of endoscopic activity using recently developed FC home test using smartphone application (FC-IBDoc) against standard enzyme-linked immunosorbent assay (ELISA).

METHODS

In all, 102 consecutive observations (89 participants) were included in prospective observational study. FC-IBDoc was performed parallelly with FC-ELISA in paediatric patients with inflammatory bowel disease indicated for endoscopy. Both tests were performed by trained staff. Mucosal healing was defined using Simple Endoscopic Score for Crohn disease (CD) ≤2 in patients with CD (n = 44), ulcerative colitis (UC) Endoscopic Index of Severity ≤4 in patients with UC (n = 27) and Rutgeerts score i0 and i1 without colon involvement in patients with CD after ileocaecal resection (n = 19).

RESULTS

Out of 102 endoscopic findings 23 were assessed as mucosal healing. We found an association of the mucosal healing scores of the entire group both with FC-ELISA (P = 0.002) and FC-IBDoc (P = 0.001). The area under the receiver operating characteristic curve for FC-ELISA was 0.883 (95% confidence interval 0.807-0.960), with optimal cut-off at 136.5 μg/g. The area under the receiver operating characteristic curve for FC-IBDoc was 0.792 (95% confidence interval 0.688-0.895) with optimal cut-off at 48 μg/g. The FC-ELISA was more accurate than FC-IBDoc when tested by a Delong test (P = 0.023).

CONCLUSIONS

Standard FC-ELISA for FC evaluation is more reliable predictor of mucosal healing than the FC-IBDoc in paediatric patients with inflammatory bowel disease. The cut-off values for both tests were incongruous.

A Treat-to-Target Update in Ulcerative Colitis: A Systematic Review

OBJECTIVES

In 2015, the Selecting Therapeutic Targets in Inflammatory Bowel Disease (STRIDE) program proposed shifting the therapeutic focus on ulcerative colitis (UC) toward altering the natural history of the disease course by regularly monitoring objective measurements of disease activity and tailoring treatment accordingly. The therapeutic paradigm shift was well received in the research community and is often cited. However, new evidence on optimal UC treatment targets continues to accumulate since the time of the STRIDE guidelines. This systematic review summarizes the evidence accrued since the STRIDE UC recommendations, discusses the barriers for adoption of treat-to-target approaches in clinical practice in UC, and suggests directions for future research.

METHODS

We systematically reviewed MEDLINE for studies from the time of the STRIDE systematic review up to March 31, 2018, that assessed the potential treatment targets identified by the STRIDE recommendations.

RESULTS

Each potential treatment target literature search returned > 200 articles, which were then reviewed by 2 independent investigators for relevant studies. Selected studies of clinical factors, patient-reported outcomes, endoscopy, histology, imaging, and biomarkers and implications on treatment targets are summarized.

CONCLUSIONS

It appears that the relative weight given to different therapeutic targets in the development and improvement of UC treatments could be optimized, with an increased emphasis on endoscopic and histological targets over clinical or symptomatic targets. For this evolution to occur, however, new research has to demonstrate that the treat-to-target approach will deliver on the promise of better long-term outcomes compared with current approaches.

IBDoc Canadian User Performance Evaluation

BACKGROUND

Fecal calprotectin (FC) is a stool biomarker that has been shown to be sensitive and specific for mucosal inflammation in patients with inflammatory bowel disease (IBD). The test is limited by the requirement for patients to collect and return stool samples. A home-based FC test may improve test adherence. The aim of this study is to evaluate the usability of the IBDoc, a home-based FC measuring test, and to determine the accuracy of results compared with traditional lab-based ELISA values.

METHODS

Patients were prospectively enrolled from 3 tertiary sites across Canada between May and August 2017. Patients completed a questionnaire establishing ease-of-use of the IBDoc. Patients completed a FC measurement using the IBDoc, and results were compared with an ELISA-determined FC measurement on the same stool sample.

RESULTS

Sixty-one participants were enrolled in the study (29 CD, 32 UC). Seventy-nine percent of patients (48 of 61) agreed that the IBDoc was easy to use, with 85% (52 of 61) of patients strongly agreeing that they were willing use the home kit in the future. The IBDoc and ELISA measurement comparison showed an 88% agreement across all values. There were no false positives or negatives using qualitative comparison.

CONCLUSIONS

The home-based IBDoc FC measuring test is acceptable to patients and correlates extremely well with the standard ELISA-determined FC value. The IBDoc enables clinicians to more easily adopt a treat-to-target approach, improve long-term outcomes, and patients' quality of life with IBD. This study is registered at ClinicalTrials.gov, number NCT03408249.

Big data in IBD: a look into the future

Big data methodologies, made possible with the increasing generation and availability of digital data and enhanced analytical capabilities, have produced new insights to improve outcomes in many disciplines. Application of big data in the health-care sector is in its early stages, although the potential for leveraging underutilized data to gain a better understanding of disease and improve quality of care is enormous. Owing to the intrinsic characteristics of inflammatory bowel disease (IBD) and the management dilemmas that it imposes, the implementation of big data research strategies not only can complement current research efforts but also could represent the only way to disentangle the complexity of the disease. In this Review, we explore important potential applications of big data in IBD research, including predictive models of disease course and response to therapy, characterization of disease heterogeneity, drug safety and development, precision medicine and cost-effectiveness of care. We also discuss the strengths and limitations of potential data sources that big data analytics could draw from in the field of IBD, including electronic health records, clinical trial data, e-health applications and genomic, transcriptomic, proteomic, metabolomic and microbiomic data.

Head-to-head comparison of three stool calprotectin tests for home use

Objective

Treatment decisions in inflammatory bowel diseases are increasingly based on longitudinal tracking of calprotectin results. Many hospital laboratories measure calprotectin levels in sent-in stool samples with an enzyme-linked immunosorbent assay (ELISA). Several manufacturers introduced a lateral flow–based test with software application that turns a smartphone camera into a reader for quantitative measurements. We compared three home tests (IBDoc, QuantonCal and CalproSmart) and companion ELISA tests (fCAL, IDK-Calprotectin and Calprotectin-ALP) to see if measurement pairs agreed sufficiently.

Design

A method comparison study was conducted with stool samples from patients with active or quiescent inflammatory bowel disease. Medical students without any specific laboratory training carried out the home tests with two iOS (iPhone 6 and 7) and two Android devices (Samsung Galaxy S6 and Motorola Moto G5 Plus). Two experienced laboratory technicians measured the calprotectin concentration with the ELISA method. Primary outcome was test agreement (defined as percentage of paired measurements within predefined limits of difference). Secondary outcome included reading error rate (RER) per smartphone type.

Results

We performed 1440 smartphone readings and 120 ELISA tests. In the low calprotectin range (≤500 μg/g) IBDoc, QuantOnCal and CalproSmart showed 87%, 82% and 76% agreement with their companion ELISAs. In the high range (>500 μg/g) the agreement was 37%, 19% and 37%, respectively. CalproSmart and QuantOnCal had significantly higher RERs than IBDoc (respectively 5.8% and 4.8%, versus 1.9%). Forty-three percent of reading errors was on the Motorola device, in particular with the QuantOnCal application.

Conclusions

All three calprotectin home tests and companion ELISAs agreed sufficiently when concentrations are ≤500 μg/g. To minimize wrongful interpretation of calprotectin changes over time it is essential to always use the home test and companion ELISA of one and the same manufacturer. Manufacturers should explicitly evaluate and report the suitability of commonly used smartphones for quantitative calprotectin readings.

Cost-effectiveness of faecal calprotectin used in primary care in the diagnosis of inflammatory bowel disease

OBJECTIVE

Inflammatory bowel disease (IBD) is a chronic, autoimmune, gastrointestinal disorder. Canada has one of the highest prevalence and incidence rates of IBD in the world. Diagnosis is challenging due to the similarity of symptoms to functional gastrointestinal disorders. Faecalcalprotectin (FC) is a biomarker for active mucosal inflammation and has proven effective in the diagnosis of IBD. Our study objective was to assess the cost-effectiveness of adding an FC test compared with standard practice (blood test) in primary care among adult patients presenting with gastrointestinal symptoms.

DESIGN

We constructed a decision analytic tree with a 1-year time horizon. The cut-off level of 100 µg/g was used for FC testing. Probabilistic analyses were conducted for the base case and all scenarios.

SETTING

Canadian health sector perspective.

POPULATION

A hypothetical cohort of adult patients presenting with gastrointestinal symptoms in the primary care setting.

INTERVENTIONS

FC test compared with blood test.

MAIN OUTCOME MEASURES

Costs, quality-adjusted life years (QALYs), incremental cost-effectiveness ratio (ICER) of FC test expressed as cost per QALY gained compared with blood test and time to IBD diagnosis.

RESULTS

FC testing is expected to cost more ($C295.1 vs $C273.9) than standard practice but yield little higher QALY (0.751vs0.750). The ICER of FC test was $C20 323 per QALY. Probabilistic analysis demonstrated that at a willingness-to-pay threshold of $C50 000 per QALY, there was 81.3% probability of FC test being cost-effective. The use of FC test in primary care reduced the time to IBD diagnosis by 40.0 days (95% CI 16.3 to 65.3 days), compared with blood testing alone.

CONCLUSIONS

Based on this analysis of short-term outcomes, screening adult patients in primary care using FC test at a cut-off level of 100 µg/g is expected to be cost-effective in Canada.

The novel latex agglutination turbidimetric immunoassay system for simultaneous measurements of calprotectin and hemoglobin in feces

Background/Aims

Fecal calprotectin (Fcal) as well as the fecal immunochemical test (FIT) are useful biomarkers for detecting activity and mucosal healing in inflammatory bowel diseases. Here, we report the performance of simultaneous measurements of Fcal and FIT for ulcerative colitis (UC) patients using the newly-developed latex agglutination turbidimetric immunoassay (LATIA) system.

Methods

Fcal and hemoglobin were measured by the LATIA system in 152 UC patients who underwent colonoscopy. Fcal was also quantified with a conventional enzyme-linked immunosorbent assay (ELISA). Fecal markers were evaluated in conjunction with the mucosal status of UC, which was assessed via the Mayo endoscopic subscore (MES) classification.

Results

The LATIA system could quantify calprotectin and hemoglobin simultaneously with the same fecal samples within 10 minutes. The values of the Fcal-LATIA closely correlated with those of the Fcal-ELISA (Spearman rank correlation coefficient, r=0.84; P<0.0001). The values of Fcal for each assay and the FIT all significantly correlated with the MESs (Spearman rank correlation coefficient, Fcal-LATIA: r=0.58, Fcal-ELISA: r=0.55, and FIT: r=0.72). The mucosal healing predictability (determined by an MES of 0 alone) of the Fcal-LATIA, Fcal-ELISA, and FIT-LATIA with the cutoffs determined by receiver operating characteristic curve analysis was 0.79, 0.78, and 0.92 for sensitivity, respectively, and 0.78, 0.69, and 0.73 for specificity, respectively.

Conclusions

The performance of the novel Fcal-LATIA was equivalent to that of the conventional Fcal assay. Simultaneous measurements with FITs would promote the clinical relevance of fecal biomarkers in UC.

Experience of patients with inflammatory bowel disease in using a home fecal calprotectin test as an objective reported outcome for self-monitoring

Background/Aims

Fecal calprotectin (fC) level is a predictive marker of mucosal healing for patients with inflammatory bowel disease (IBD). Home fC tests are now available. We evaluated the performance of the smartphone-based IBDoc home testing system in patients with IBD and obtained their feedback as an objective patient-reported outcome.

Methods

This prospective study enrolled consecutive patients with IBD in clinical remission. fC in the same stool sample was assessed by using both the laboratory test (Quantum Blue calprotectin test) and home test (IBDoc). The correlation between the 2 tests was analyzed using the Pearson method. In addition, the patients were asked to fill a questionnaire based on their experience.

Results

Fifty-one patients with IBD (68 tests and 49 questionnaires) were included. The correlation between Quantum Blue test and IBDoc was good (r=0.776, P<0.0001). After the test, 56% patients found IBDoc easy to perform, and 96% were satisfied with it. Thirty-nine patients (80%) had a strong (>70%) probability to use it for future monitoring if the price was acceptable. By using 250 μg/g as the cutoff, the agreement between home test and laboratory results was 80%, and by using 600 μg/g as the cutoff, the agreement increased to 92%.

Conclusions

The correlation between the laboratory and home tests was good. Most patients found the home test to be feasible and easy to use and preferred it over laboratory test and endoscopy for monitoring. Therefore, the home test could be used as an objective patient-reported outcome.

Fecal Calprotectin

Calprotectin is a 36kDa member of the S100 family of proteins. It is derived predominantly from neutrophils and has direct antimicrobial effects and a role within the innate immune response. Calprotectin is found in various body fluids in proportion to the degree of any existing inflammation and its concentration in feces is about six times that of plasma. Measurement of fecal calprotectin is a useful surrogate marker of gastrointestinal inflammation. It has a high negative predictive value in ruling out inflammatory bowel disease (IBD) in undiagnosed, symptomatic patients and a high sensitivity for diagnosing the disease making it useful as a tool for prioritising endoscopy. In patients with known IBD, fecal calprotectin can be a useful tool to assist management, providing evidence of relapse or mucosal healing to enable therapy to be intensified or reduced. There are a number of commercial calprotectin assays with marked difference in performance as judged by external quality assessment and at present no standardised reference material exists. Various factors may affect results including age, medication and day to day variation. Laboratories should therefore be mindful of the characteristics of their own assay and factors that may affect results.

Point of care testing of fecal calprotectin as a substitute for routine laboratory analysis

Objectives

Fecal calprotectin (FC) is widely used to monitor the activity of inflammatory bowel disease (IBD) and to tailor medical treatment to disease activity. Laboratory testing of fecal samples may have a turnaround time of 1–2 weeks, whereas FC home testing allows results within hours and thus enables a rapid response to clinical deterioration.

Design and methods

Fifty-five stool samples were analyzed by the IBDoc^® Calprotectin Home Testing kit and the BÜHLMANN fCAL^® turbo assay on a Roche Cobas 6000 c501. The correlation between the assays was assessed using Spearman's Rho correlation coefficient and the intermediate imprecision of both assays was calculated.

Results

We found a strong correlation coefficient of 0.887 between FC measured on IBDoc® and the laboratory assay BÜHLMANN fCAL^® turbo. The coefficients of variation (CVs) at three different FC levels were in the range 2.3–5.5% (BÜHLMANN fCAL^® turbo) and in the range of 4.8–26.6% (IBDoc^®).

Conclusions

This study suggests that IBDoc® is a suitable alternative for the assessment of disease activity in IBD patients.