Clinical utility of fecal biomarkers for the diagnosis and management of inflammatory bowel disease

Comparison of different histological indexes in the assessment of UC activity and their accuracy regarding endoscopic outcomes and faecal calprotectin levels

OBJECTIVE

Histological remission is being increasingly acknowledged as a therapeutic endpoint in patients with UC. The work hereafter described aimed to evaluate the concordance between three histological classification systems-Geboes Score (GS), Nancy Index (NI) and RobartsHistopathologyIndex (RHI), as well as to evaluate their association with the endoscopic outcomes and the faecal calprotectin (FC) levels.

DESIGN

Biopsy samples from 377 patients with UC were blindly evaluated using GS, NI and RHI. The results were compared with the patients' Mayo Endoscopic Score and FC levels.

RESULT

GS, NI and RHI have a good concordance concerning the distinction between patients in histological remission or activity. RHI was particularly close to NI, with 100% of all patients classified as being in remission with NI being identified as such with RHI and 100% of all patients classified as having activity with RHI being identified as such with NI. These scores could also predict the Mayo Endoscopic Score and the FC levels, with their sensitivity and specificity levels depending on the chosen cut-offs. Moreover, higher FC levels were statistically associated with the presence of neutrophils in the epithelium, as well as with ulceration or erosion of the intestinal mucosa.

CONCLUSIONS

GS, NI and RHI histopathological scoring systems are comparable in what concerns patients' stratification into histological remission/activity. Additionally, FC levels are increased when neutrophils are present in the epithelium and the intestinal mucosa has erosions or ulcers. The presence of neutrophils in the epithelium is, indeed, the main marker of histological activity.

Lewis Score on Capsule Endoscopy as a Predictor of the Risk for Crohn's Disease-Related Emergency Hospitalization and Clinical Relapse in Patients with Small Bowel Crohn's Disease

Background

Small bowel capsule endoscopy (CE) is a useful tool for evaluating the mucosal changes in patients with Crohn's disease (CD). The Lewis score (LS) on CE could be used to objectively assess the inflammatory activity of the small bowel mucosa. However, only few reports on the correlation between the LS and CD prognosis exist. This study is aimed at evaluating the clinical significance of the LS by determining the cutoff value of the LS that could predict CD-related emergency hospitalization.

Methods

This retrospective single-center study included 125 patients who underwent CE for small bowel CD. Eighty-six patients whose treatment was not changed after CE were analyzed. Inflammatory activity was assessed with the LS. We examined the clinical course of the patients who could be observed for 1 year after CE and investigated the LS cutoff value that could predict CD-related emergency hospitalization within 1 year. We also examined the hospitalization-free and clinical relapse-free rates using the LS cutoff value and evaluated the factors related to emergency hospitalization.

Results

The LS cutoff value that could predict CD-related emergency hospitalization within 1 year was 264 (area under the curve, 0.92 (P < 0.001); sensitivity, 0.80; and specificity, 0.94). The cumulative hospitalization-free rate and cumulative clinical relapse-free rate were significantly higher in patients with a LS < 264 (P < 0.001). Multivariate analysis showed that a LS < 264 was a statistically significant factor (P = 0.001; 95% CI, 0.010–0.308).

Conclusion

A LS of 264 is a useful cutoff value that could predict CD-related emergency hospitalization. This LS cutoff value may help determine treatment strategies for CD.

Defining Failure of Medical Therapy for Inflammatory Bowel Disease

Over the past 2 decades, advances in biologic and small molecule therapeutics have resulted in a rapid increase in our armamentarium of therapies for inflammatory bowel disease. Despite these advancements, Crohn's disease and ulcerative colitis remain chronic and progressive diseases. One of the primary reasons for persistent inflammation and bowel damage is failure of medical therapy. With growing therapeutic options, there is an increased temptation to quickly move to the next therapy and label the prior therapy as a failure; however, this can lead to inadequate optimization of medications and poor control of disease. On the other hand, failure to recognize ongoing mucosal inflammation despite optimized treatment and moving to the next agent can lead to progression of disease and long-term complications. As our options for medical therapy continue to increase, it has become more important to recognize failure of therapy in order to promptly move to the next therapeutic agent without abandoning therapies prematurely. In this review, we aim to define failure of medical therapy for inflammatory bowel disease with the goal of offering guidance on when it is appropriate to attempt optimization of current medical treatment as opposed to moving on to the next agent or treatment approach.

The sensitivity of fecal calprotectin in predicting deep remission in ulcerative colitis

BACKGROUND

Mucosal healing is proposed as treat-to-target in ulcerative colitis (UC), even though the definition of mucosal healing remains contested as it has been suggested to be assessed by either endoscopy, histology or both. However, all definitions require an endoscopic evaluation of the mucosa. As endoscopies are invasive and uncomfortable to the patient we aimed to calibrate noninvasive predictors of mucosal inflammatory status defined by both endoscopy and histology.

METHODS

UC patients (n = 106) undergoing a sigmoid-/colonoscopy were prospectively included. Feces (fecal calprotectin, FC), blood samples (hemoglobin, C-reactive protein, orosomucoid, erythrocyte sedimentation rate, albumin) and symptom scores (Simple Clinical Colitis Activity Index, SSCAI) were collected and analyzed. The colonic mucosa was assessed by the Mayo endoscopic sub score and biopsies were obtained for a histologic grading by Geboes score. Predictive cutoff values were analyzed by receiver operating characteristics (ROC). A combined endoscopic and histologic assessment defined deep remission (Mayo =0 and Geboes ≤1) and activity (Mayo ≥2 and Geboes >3).

RESULTS

Only FC showed a significant ROC curve (p < .05). We suggest FC (mg/kg) cutoffs for detection of following: Deep remission: FC ≤25; Indeterminate: FC 25-230 - an endoscopy is recommended if a comprehensive status of both endoscopic and histologic assessed activity is needed; Active disease: FC >230. The complete ROC data is presented, enabling extraction of an FC cutoff value's sensitivity and specificity.

CONCLUSIONS

FC predicts endoscopic and histologic assessed deep remission and inflammatory activity of colon mucosa. Neither the markers in blood nor the SCCAI performed significant ROC results.

Oral iron exacerbates colitis and influences the intestinal microbiome

Inflammatory bowel disease (IBD) is associated with anaemia and oral iron replacement to correct this can be problematic, intensifying inflammation and tissue damage. The intestinal microbiota also plays a key role in the pathogenesis of IBD, and iron supplementation likely influences gut bacterial diversity in patients with IBD. Here, we assessed the impact of dietary iron, using chow diets containing either 100, 200 or 400 ppm, fed ad libitum to adult female C57BL/6 mice in the presence or absence of colitis induced using dextran sulfate sodium (DSS), on (i) clinical and histological severity of acute DSS-induced colitis, and (ii) faecal microbial diversity, as assessed by sequencing the V4 region of 16S rRNA. Increasing or decreasing dietary iron concentration from the standard 200 ppm exacerbated both clinical and histological severity of DSS-induced colitis. DSS-treated mice provided only half the standard levels of iron ad libitum (i.e. chow containing 100 ppm iron) lost more body weight than those receiving double the amount of standard iron (i.e. 400 ppm); p<0.01. Faecal calprotectin levels were significantly increased in the presence of colitis in those consuming 100 ppm iron at day 8 (5.94-fold) versus day-10 group (4.14-fold) (p<0.05), and for the 400 ppm day-8 group (8.17-fold) versus day-10 group (4.44-fold) (p<0.001). In the presence of colitis, dietary iron at 400 ppm resulted in a significant reduction in faecal abundance of Firmicutes and Bacteroidetes, and increase of Proteobacteria, changes which were not observed with lower dietary intake of iron at 100 ppm. Overall, altering dietary iron intake exacerbated DSS-induced colitis; increasing the iron content of the diet also led to changes in intestinal bacteria diversity and composition after colitis was induced with DSS.

Elastase as a potential biomarker for radiation-induced gut wall injury of the distal bowel in an experimental mouse model

BACKGROUND AND PURPOSE

Traditionally, elastase has been used to study exocrine activity of the pancreas in patients with chronic pancreatitis and cystic fibrosis, and calprotectin as a marker for gut-wall inflammation in patients with inflammatory bowel disease. The aim of the study was to find out whether elastase and calprotectin could be used as inflammatory markers for radiation-induced gut wall injury of the distal bowel.

MATERIAL AND METHODS

Adult male mice were exposed to two, three, or four fractions of 6 Gy or 8 Gy irradiation to the sigmoid and rectum of the large bowel, using a linear accelerator. Fecal samples were collected from mice at 1, 3, and 6 weeks post-irradiation. The fecal levels of elastase and calprotectin were analyzed using ELISA.

RESULTS

Three and 6 weeks after irradiation, we found a dose-effect relationship between dose of ionizing radiation and the fecal level of elastase; that is significantly higher levels of elastase were observed in mice that had received a high irradiation dose. We also found that irradiated mice hosted in the same cage had a comparable level (either high or low) of elastase. No significant differences were observed from the calprotectin data.

CONCLUSIONS

We found a clear association between the dose of ionizing radiation to the distal colon and the level of elastase in the fecal samples.

Fecal calprotectin for detection of postoperative endoscopic recurrence in Crohn's disease: systematic review and meta-analysis

BACKGROUND

Anastomotic recurrence is frequent in patients with Crohn's disease (CD) following ileocecal resection. The degree of endoscopic recurrence, quantified by the Rutgeerts score (RS), correlates with risk of clinical and surgical recurrence. Several studies demonstrate the accuracy of fecal calprotectin (FC) for detection of endoscopic recurrence, however the optimal threshold FC value remains to be established. The aim of our meta-analysis was to evaluate the accuracy of common FC cut-offs for detection of endoscopic recurrence.

METHODS

We performed a systematic literature search for studies evaluating postoperative recurrence in CD which reported RS and FC levels. Endoscopic recurrence was defined as RS = 2-4 (or RS ⩾ 2). We calculated pooled diagnostic sensitivity, specificity, diagnostic odds ratio (DOR) and constructed summary receiver operating characteristic (SROC) curves for each available FC cut-off value.

RESULTS

A total of 54 studies were retrieved; 9 studies were eligible for analysis. Diagnostic accuracy was calculated for FC values of 50, 100, 150 and 200 µg/g. A significant threshold effect was observed for all FC values. The optimal diagnostic accuracy was obtained for FC value of 150 µg/g, with a pooled sensitivity of 70% [95% confidence interval (CI) 59-81%], specificity 69% (95% CI 61-77%), and DOR 5.92 (95% CI 2.61-12.17). The area under the SROC curve was 0.73.

CONCLUSION

FC is an accurate surrogate marker of postoperative endoscopic recurrence in CD patients. The FC cut-off 150 μg/g appears to have the best overall accuracy. Serial FC evaluations may eliminate or defer the need for colonoscopic evaluation in up to 70% of postoperative CD patients.

Which evidence for a treat to target strategy in ulcerative colitis?

The main therapeutic goal of in ulcerative colitis is to maintain disease remission. The new concept of deep remission implies also a complete mucosal healing. Histological assessment of disease in UC seems to be an important prognostic factor to predict disease outcome. In this article we review current definitions of mucosal healing, histological healing, histological remission and available histological scores assessing histological activity of disease in ulcerative colitis. Comparison between mucosal healing and histological remission shows that histological remission is a better prognostic factor than mucosal healing to predict outcome in ulcerative colitis and could be a new therapeutic goal in ulcerative colitis but actually histology is not a target due to lack of evidence of clinical utility. Some investigations are needed to clearly defined histological remission and to determine its role in therapeutic strategy. Futhermore histological assessment remains an invasive exploration and other alternative as faecal markers are discuss to predict ulcerative outcome.

Fecal calprotectin in management of Clostridium difficile infection: a longitudinal study

BACKGROUND

Clostridium difficile infection (CDI) is characterized by a relevant intestinal neutrophil infiltrate. So far, role of fecal calprotectin in CDI, has been investigated only in few studies, mainly focused on diagnosis of the disease.

AIM

By a longitudinal design, we assess fecal calprotectin concentrations (FCCs) in subjects with CDI, evaluating the correlation between fecal marker and response to therapy.

METHODS

Clinical (diarrhea scoring) and laboratory (FCCs and leucocytes count) evaluation was performed in 56 subjects with CDI at time of diagnosis (T₀) and after a week from starting of therapy (T₁). Clinical response to therapy at T₁ was related with both T₀ and T₁ FCC values. FCCs were also related to all-cause 30-day mortality, recurrence and death, both of them within 90 days.

RESULTS

FCCs at T₁ were significantly increased in subjects with persistence of diarrhea in respect to the other ones (285.5 ± 270 µg/g vs 150.7 ± 147 µg/g, respectively; p < .05). Patients who did not respond to therapy showed higher, but not significative, FCCs at T₀ than patients who responded. No correlation was found among FCCs, both at T₀ and T₁, and the other outcomes.

CONCLUSIONS

Longitudinal evaluation of FCCs in patients with CDI could support physicians in clinical management of disease, for example in term of duration (10 vs 14 days) or type (first vs second line therapy). Further and larger studies could confirm the eventual role of this marker in prognostic algorithms, mainly in prediction of recurrence.

Detection of Crohn Disease in Patients with Spondyloarthropathy: The SpACE Capsule Study

OBJECTIVE

Inflammatory bowel disease (IBD) is generally reported to be associated with spondylarthropathies (SpA) in 5%-15% of cases. Systematic colonoscopic assessment by protocol demonstrated mucosal inflammation characteristic of Crohn disease (CD) in up to one-third of patients with SpA. Video capsule endoscopy (CE) is a superior diagnostic tool to detect small bowel mucosal disease. Our study compared the accuracy of CE to standard colonoscopy for detection of inflammatory bowel lesions in patients with SpA, and to describe predictors of small bowel inflammation (SBI) in this cohort.

METHODS

Prospective cross-sectional study of adult patients followed for SpA. Patients were evaluated by CE and standard colonoscopy with biopsies. SBI was quantified using the Lewis Score. Additional screening tests included fecal calprotectin (FCP), C-reactive protein (CRP), and a diagnostic panel of serologic, inflammatory and genetic tests (SGI).

RESULTS

There were 64 patients recruited (53% female, mean age 42 ± 13 yrs). Chronic gastrointestinal (GI) symptoms were present in 57%. CE revealed significant SBI in 27/64 (42.2%), compared to 7/64 (10.9%) by standard colonoscopy (p = 0.035). Elevated FCP was associated with small bowel CD (OR 4.5, 95% CI 1.01-19.9; p = 0.042). No correlation was observed with presence of GI symptoms, CRP, or SGI results. Finding CD led to a change in management in 65.2% of cases.

CONCLUSION

CE uncovered SBI consistent with CD in 42.2% of patients with SpA, with a significant incremental yield over colonoscopy of 31%. FCP levels were significantly correlated with CE results, while GI symptoms and SGI results were poor predictors of SBI.

Accuracy of fecal calprotectin for the prediction of endoscopic activity in patients with inflammatory bowel disease

BACKGROUND

Fecal calprotectin is a noninvasive marker of inflammatory bowel disease.

AIM

To evaluate the accuracy of calprotectin for prediction of endoscopic activity in inflammatory bowel disease.

METHODS

One-hundred patients were prospectively included. Quantum Blue^® (Bühlmann) kits were used to determine calprotectin. Endoscopic activity was calculated. Various serum markers (platelets, leukocytes, C-reactive protein, and albumin) were recorded.

RESULTS

Calprotectin was higher in patients with endoscopic activity than in those without activity: in ulcerative colitis, with the low- (29 ± 14 vs. 301 ± 174, p < 0.001) and high- (99 ± 727 vs. 617 ± 801, p < 0.001); and in Crohn's disease, with the low- (29 ± 59 vs. 124 ± 268, p < 0.01) and high-range kit (99 ± 37 vs. 287 ± 607, p < 0.01). Serological marker concentrations did not vary with endoscopic activity. The area under the ROC curve of calprotectin for the prediction of endoscopic activity was 0.9 in ulcerative colitis and 0.8 in Crohn's disease. The best cut-off points for the detection of activity in ulcerative colitis were 50 for the low- (sensitivity 85%, specificity 79%) and 102 for the high- (sensitivity 85%, specificity 79%); in Crohn's disease, 54 for the low- (sensitivity 71%, specificity 75%) and 122 for the high-range kit (sensitivity 71%, specificity 75%).

CONCLUSIONS

Fecal calprotectin concentration has good diagnostic accuracy for the detection of endoscopic activity in inflammatory bowel disease and performs better in ulcerative colitis than in Crohn's disease.

Within-Stool and Within-Day Sample Variability of Fecal Calprotectin in Patients With Inflammatory Bowel Disease: A Prospective Observational Study

BACKGROUND AND GOALS

The use of fecal calprotectin (FC) as a stool biomarker for differentiating inflammatory bowel disease (IBD) from IBS has been well validated, and there is a strong correlation between FC and the presence of endoscopic inflammatory lesions. However, recent studies have demonstrated intraindividual sample variability in patients with IBD, possibly limiting the reliability of using a single sample for monitoring disease activity. Our aim was to assess the within-stool and within-day sample variability of FC concentrations in patients with IBD.

STUDY

We examined a cross-sectional cohort of 50 adult IBD patients. Eligible patients were instructed to collect 3 samples from different parts of the stool from their first bowel movement of the day and 3 samples from each of up to 2 additional bowel movements within 24 hours. FC concentrations were measured by a rapid, quantitative point-of-care test using lateral flow technology (Quantum Blue). Descriptive statistics were used to assess FC variability within a single bowel movement and between different movements at different FC positivity cutoffs.

RESULTS

Within a single bowel movement, there was clinically significant sample variability ranging from 8% to 23% depending on the time of the day or on the FC positivity cutoff value. Between bowel movements, there was clinically significant sample variability ranging from 13% to 26% depending on the FC positivity cutoff.

CONCLUSIONS

Considering a single FC sample, the first sample of the day with an FC positivity cutoff of 250 μg/g provided the most reliable indication of disease activity.

European Crohn's and Colitis Organisation Topical Review on Treatment Withdrawal ['Exit Strategies'] in Inflammatory Bowel Disease

Clinically effective therapies now exist for remission maintenance in both ulcerative colitis [UC] and Crohn's Disease [CD]. For each major class of IBD medications [5-aminosalicyclates, immunomodulators, and biologic agents], used alone or in combination, there is a risk of relapse following reduction or cessation of treatment. A consensus expert panel convened by the European Crohn's and Colitis Organisation [ECCO] reviewed the published literature and agreed a series of consensus practice points. The objective of the expert consensus is to provide evidence-based guidance for clinical practice so that physicians can make informed decisions in partnership with their patients. The likelihood of relapse with stopping each class of IBD medication is reviewed. Factors associated with an altered risk of relapse with withdrawal are evaluated, and strategies to monitor and allow early identification of relapse are considered. In general, patients in clinical, biochemical, and endoscopic remission are more likely to remain well when treatments are stopped. Reintroduction of the same treatment is usually, but not always, successful. The decision to stop a treatment needs to be individualized, and shared decision making with the patient should take place.

Predicting Hospitalization and Outpatient Corticosteroid Use in Inflammatory Bowel Disease Patients Using Machine Learning

BACKGROUND

Inflammatory bowel disease (IBD) is a chronic disease characterized by unpredictable episodes of flares and periods of remission. Tools that accurately predict disease course would substantially aid therapeutic decision-making. This study aims to construct a model that accurately predicts the combined end point of outpatient corticosteroid use and hospitalizations as a surrogate for IBD flare.

METHODS

Predictors evaluated included age, sex, race, use of corticosteroid-sparing immunosuppressive medications (immunomodulators and/or anti-TNF), longitudinal laboratory data, and number of previous IBD-related hospitalizations and outpatient corticosteroid prescriptions. We constructed models using logistic regression and machine learning methods (random forest [RF]) to predict the combined end point of hospitalization and/or corticosteroid use for IBD within 6 months.

RESULTS

We identified 20,368 Veterans Health Administration patients with the first (index) IBD diagnosis between 2002 and 2009. Area under the receiver operating characteristic curve (AuROC) for the baseline logistic regression model was 0.68 (95% confidence interval [CI], 0.67-0.68). AuROC for the RF longitudinal model was 0.85 (95% CI, 0.84-0.85). AuROC for the RF longitudinal model using previous hospitalization or steroid use was 0.87 (95% CI, 0.87-0.88). The 5 leading independent risk factors for future hospitalization or steroid use were age, mean serum albumin, immunosuppressive medication use, and mean and highest platelet counts. Previous hospitalization and corticosteroid use were highly predictive when included in specified models.

CONCLUSIONS

A novel machine learning model substantially improved our ability to predict IBD-related hospitalization and outpatient steroid use. This model could be used at point of care to distinguish patients at high and low risk for disease flare, allowing individualized therapeutic management.

Prospective Comparison of Standard- Versus Low-Radiation-Dose CT Enterography for the Quantitative Assessment of Crohn Disease

OBJECTIVE

CT enterography (CTE) is sensitive and specific for active inflammatory changes of Crohn disease (CD), but its use has been limited by exposure to ionizing radiation. The objective of this study is to show the noninferiority of a model-based iterative reconstruction (MBIR) technique using lower radiation doses compared with standard-dose CTE in the assessment of CD.

SUBJECTS AND METHODS

Patients referred to a hospital radiology department for CTE for the evaluation of CD underwent both a standard examination (used to generate filtered back-projection and adaptive statistical iterative reconstruction [ASIR] images) and low-dose MBIR CTE performed in a random sequence on the same day. Images were reviewed by two radiologists for signs of small-bowel CD. Radiologic findings obtained using ASIR and clinical assessments of disease activity served as the reference standard for comparison with low-dose CTE findings.

RESULTS

A total of 163 patients, 92 (56.4%) of whom had active disease, underwent CTE. MBIR was found to be noninferior to the two standard-dose techniques, with no significant differences noted between the three types of images when compared with the clinical reference standard. As compared with the radiologic standard of ASIR, the very-low-dose scans had a high degree of accuracy, with sensitivity ranging from 0.85 to 0.94 and specificity ranging from 0.84 to 0.97 depending on the reader. A significant reduction in radiation exposure was noted with MBIR (mean [± SD] reduction, 3.30 ± 3.17 mSv) versus standard-dose imaging (7.16 ± 4.61 mSv; p < 0.001).

CONCLUSION

Low-dose CTE using MBIR is sensitive and specific for the detection of active inflammatory changes of CD while utilizing radiation doses substantially lower than those associated with standard techniques.

Capsule Endoscopy, Magnetic Resonance Enterography, and Small Bowel Ultrasound for Evaluation of Postoperative Recurrence in Crohn's Disease: Systematic Review and Meta-Analysis

BACKGROUND

Anastomotic recurrence is frequent in patients with Crohn's disease (CD) following ileocecal resection. The degree of endoscopic recurrence, quantified by the Rutgeerts score (RS), is correlated with the risk of clinical and surgical recurrence. Noninvasive modalities such as capsule endoscopy (CE), magnetic resonance enterography (MRE), and intestinal ultrasound (US) may yield similar information without the need for ileocolonoscopy (IC). The aim of our meta-analysis was to evaluate the accuracy of those modalities for detection of endoscopic recurrence in postoperative CD patients.

METHODS

We performed a systematic literature search for studies comparing the accuracy of CE, MRE, and US with IC for detection of postoperative recurrence in CD. We calculated pooled diagnostic sensitivity, specificity, diagnostic odds ratio (DOR), and area under the curve (AUC) for each comparison.

RESULTS

A total of 135 studies were retrieved; 14 studies were eligible for analysis. For CE, the pooled sensitivity was 100% (95% CI, 91%-100%), specificity was 69% (95% CI, 52%-83%), DOR was 30.8 (95% CI, 6.9-138), and AUC was 0.94. MRE had pooled sensitivity of 97% (95% CI, 89%-100%), specificity of 84% (95% CI, 62%-96%), DOR of 129.5 (95% CI, 16.4-1024.7), and AUC of 0.98. US had pooled sensitivity of 89% (95% CI, 85%-92%), specificity of 86% (95% CI, 78%-93%), DOR of 42.3 (95% CI, 18.6-96.0), and AUC 0.93.

CONCLUSIONS

CE, MRE, and US provide accurate assessment of postoperative endoscopic recurrence in CD. These modalities should gain wider use for detection of postoperative recurrence; the prognostic value of those diagnostic findings merits evaluation in further prospective studies.

Detection of calprotectin in inflammatory bowel disease: Fecal and serum levels and immunohistochemical localization

The aim of the present study was to quantify calprotectin levels using an enzyme-linked immunosorbent assay (ELISA) and a point-of-care test (POCT) in patients with inflammatory bowel disease. Overall, 113 patients with ulcerative colitis (UC; 51 men and 62 women) and 42 patients with Crohn's disease (CD; 29 men and 13 women), who were scheduled to undergo a colonoscopy, were prospectively enrolled and scored endoscopically and clinically. An additional 96 healthy, age-matched subjects served as the normal controls. Feces and blood samples from the patients with UC and CD, and the normal controls were analyzed. These patients had received adequate medical treatment. The tissue distribution of calprotectin was investigated using immunohistochemistry. The fecal calprotectin levels, as measured using an ELISA, were correlated with the endoscopic and clinical disease activities and laboratory parameters, including serum levels of hemoglobin (Hb), albumin and C-reactive protein, and erythrocyte sedimentation rate, particularly among the patients with UC. The fecal Hb level was close to that of the fecal calprotectin level (r=0.57; P<0.0001). The fecal calprotectin level measured using an ELISA was well-correlated with the fecal calprotectin level measured using the POCT (r=0.81; P<0.0001), but was not correlated with the serum calprotectin level (r=0.1013; P=0.47). An immunohistochemical investigation revealed that patients with both UC and CD had higher neutrophil and monocyte/macrophage calprotectin-positive cell expression levels, compared with those in the normal controls. Fecal calprotectin was considered a reliable marker for disease activity, and the assessment of fecal calprotectin via POCT showed potential as a rapid and simple measurement in clinical settings.

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.

Fecal calprotectin is a strong predictive marker of relapse in Chinese patients with Crohn's disease: a two-year prospective study

OBJECTIVE

To evaluate the predictive value of fecal calprotectin (FC) for clinical relapse in Chinese patients with quiescent Crohn's disease (CD) and to further investigate the correlation between FC and intestinal inflammation.

METHODS

Sixty-two patients with a diagnosis of quiescent CD were consecutively enrolled in this prospective study. Fecal samples were collected and enteroscopy were performed to detect mucosal lesions at the beginning of the study. Patients were followed until the first relapse or by the end of the two-year follow-up. The calprotectin concentration was measured using a quantitative enzyme-linked immunoassay.

RESULTS

Of the 62 CD patients, 29 had a relapse (median time of relapse: 8.44 months). The median follow-up months was 8.16 (4.98-13.59). The cut off level of 225 μg/g provided the maximal area under the receiver operating characteristic curve (AUC) of .775 for detecting the relapse of CD patients. Meanwhile, fecal occult blood had an added value. The multivariate Cox regression model showed that FC was the strongest predictor of the risk of relapse (risk ratio (RR): 6.315; p = .001). FC correlated most closely with the simple endoscopic score for Crohn's disease (SES-CD) (r = 0.524, p < .001).

CONCLUSIONS

FC correlated significantly with gut inflammation and could be a reliable predictor of relapse in Chinese patients with CD.

Correlations between ceruloplasmin, lactoferrin and myeloperoxidase in meconium

BACKGROUND AND AIMS

Oxidative stress and the generation of reactive oxygen/nitrogen species has a known significant impact on intrauterine fetal growth and the risk of metabolic diseases in adulthood. Compounds accumulated in fetal meconium may be a source of information about the oxidoreductive status during the intrauterine development. Three metal-containing proteins ceruloplasmin (CP), lactoferrin (LF) and myeloperoxidase (MPO) constitute the complementary panel modulating oxidative stress. The aim of this study was to assess the concentrations of these proteins and their correlations in meconium from healthy neonates.

METHODS

The CP, LF and MPO concentrations were determined using ELISA Kits. All serial meconium portions (n=80) were collected from healthy full-term neonates (n=19).

RESULTS

The mean±SD concentrations [μg/g] in meconium samples were as follows: CP 312.4±229.7 (range 52.2-1076), LF 45.6±78.9 (range 1.7-511.4), MPO 1.8±1.7 (range 0.02-8.8) with statistically significant correlations between CP vs. LF (R=0.459, p=0.00009) and LF vs. MPO (R=0.354, p=0.0013). A statistically significant increase in the concentrations (p<0.05) between the first and the last meconium portions was found for LF (p=0.027) and for MPO (p=0.0006).

CONCLUSIONS

Strong correlations between the meconium concentrations of CP, LF and MPO indicate a possible role of these complementary proteins in maintaining homeostasis of the intrauterine environment of the fetus. CP, LF and MPO measured in meconium may serve as biomarkers for assessment of impairment of oxidative balance during intrauterine life with its potential impact on disease development in adulthood.

Association Between Ustekinumab Trough Concentrations and Clinical, Biomarker, and Endoscopic Outcomes in Patients With Crohn's Disease

BACKGROUND & AIMS

Ustekinumab, an inhibitor of the p40 subunit of interleukins 12 and 23, is an effective treatment for patients with Crohn's disease (CD). Trough concentrations of tumor necrosis factor (TNF) antagonists and presence of anti-drug antibodies are associated with important clinical and endoscopic outcomes. We investigated associations between trough concentrations of ustekinumab and clinical, biomarker, and endoscopic outcomes of real-world patients with CD.

METHODS

We recruited 62 patients with CD who were either refractory or intolerant to TNF antagonists, treated with ustekinumab from April 2014 to September 2015. Patients received 90 mg of ustekinumab subcutaneously at weeks 0, 1, and 2 during induction and 90 mg every 4 or 8 weeks during maintenance. Clinical, biomarker, and endoscopic outcomes, trough concentrations of ustekinumab, and anti-drug antibodies were assessed at both week 10 postinduction therapy and at week 26 or later during maintenance therapy in a prospective longitudinal patient cohort or at week 26 or later during maintenance therapy in a cross-sectional patient cohort. Analysis was performed on data combined from both maintenance cohorts, which had similar outcomes at week 26 or later. A primary analysis determined if ustekinumab drug trough concentrations were associated with clinical response (reduction in Harvey Bradshaw Index score of 3 or greater), clinical remission (Harvey Bradshaw Index score <5), steroid-free clinical remission, biomarker (serum level of C-reactive protein [CRP] or level of fecal calprotectin) reduction, biomarker normalization (serum level of CRP below 5 mg/L or level of fecal calprotectin below 200 μg/g), endoscopic response (simple endoscopic score for CD reduced by 50% or more), or endoscopic remission (simple endoscopic score for CD of 2 or less).

RESULTS

At week 26 or beyond, 80.7% of patients had a clinical response, 66.1% were in clinical remission, 50.0% were in steroid-free clinical remission, 58.9% had an endoscopic response, and 19.6% were in endoscopic remission. The mean trough concentration of ustekinumab at this time point was higher in patients with an endoscopic response (4.7 μg/mL) than without (3.8 ug/mL; P = .03). An optimal ustekinumab threshold trough concentration at week 26 or later was found to be 4.5 μg/mL (area under the curve, 0.67). A greater proportion of patients with trough concentrations of ustekinumab above 4.5 μg/mL at week 26 or later had an endoscopic response (75.9%) than did patients with trough concentrations below this level (40.7%; P = .008). Patients with trough concentrations of ustekinumab above 4.5 μg/mL at week 26 or later also had a lower mean level of CRP (12.6 mg/L) than did patients with trough concentrations below this level (mean level of CRP, 23.9 mg/L; P = .04). We did not detect antibodies against ustekinumab in any patient.

CONCLUSIONS

Ustekinumab therapy was effective in patients with CD who had not responded to or were intolerant to treatment with a TNF antagonist. Maintenance trough concentrations of ustekinumab above 4.5 μg/mL at 26 weeks or later were associated with biomarker reduction and endoscopic response.

Faecal biomarkers for screening small bowel inflammation in patients with Crohn's disease: a prospective study

BACKGROUND

The value of faecal biomarkers for screening small bowel inflammation in patients with Crohn's disease (CD) remains to be elucidated. This prospective study was to evaluate the utility of faecal biomarkers for detecting small intestinal inflammation.

METHODS

A total of 122 consecutive patients with a diagnosis of CD in the small intestine were screened for eligibility. Computed tomography enterography (CTE) was undertaken to evaluate small bowel inflammation followed by colonoscopy to confirm no large bowel involvement. Seventy eligible patients with inflammation confined to the small intestine were included. Faecal samples were collected for assaying calprotectin, lactoferrin and haemoglobin. For assessing the degree of small bowel inflammation, a semi-quantitative scoring system (CTE0, normal; CTE1, mild; CTE2, moderate; CTE3, severe) was applied.

RESULTS

The median calprotectin, lactoferrin and haemoglobin levels were significantly higher in patients with small bowel inflammation, CTE scores 1-3 (n = 42) versus 0 (n = 28): calprotectin, 330 versus 40 ng/ml, p < 0.0001; lactoferrin, 14 versus 3 ng/ml, p < 0.0001; haemoglobin, 29.5 versus 6.5 ng/ml, p = 0.005. There was a strong positive relationship between the faecal biomarkers and CTE score: calprotectin, p < 0.0001; lactoferrin, p < 0.0001; haemoglobin, p = 0.0004. A cutoff value of 140 ng/ml for calprotectin had a sensitivity of 69% and a specificity of 82% with an area under the receiver operating characteristic curve (AUC) of 0.82 to detect small bowel inflammation (CTE scores 1-3), while lactoferrin 6 ng/ml had a sensitivity of 69% and a specificity of 79% with an AUC of 0.83, and haemoglobin 9 ng/ml showed a sensitivity of 71% and a specificity of 39% with an AUC of 0.70.

CONCLUSIONS

Faecal calprotectin, lactoferrin, and to a lesser degree haemoglobin are relevant biomarkers for screening small bowel inflammation in CD patients without large bowel involvement. Further well-designed large-scale studies in this clinical setting should strengthen our findings.

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

BACKGROUND AND AIMS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Effect of faecal calprotectin assay variability on the management of inflammatory bowel disease and potential role of faecal S100A12

Aims

To prospectively evaluate whether between-assay variability of different faecal calprotectin (f-Cp) assays influences diagnostic accuracy for inflammatory bowel disease (IBD) in a cohort of patients with confirmed IBD and irritable bowel syndrome (IBS). To also evaluate the diagnostic accuracy of faecal S100A12 (f-S100A12) against f-Cp in the same patient cohort and assess whether f-S100A12 offers additional diagnostic value.

Methods

F-Cp using four commercially available f-Cp assays, f-S100A12 and blood biomarkers were measured in patients, recruited from the local IBD clinic, who had established IBS or active ulcerative colitis (UC) and Crohn’s disease (CD). Diagnostic sensitivities and specificities for each assay and biomarker were calculated and compared.

Results

Median f-Cp levels in all assays were significantly higher in UC (347–884 µg/g; n=28) and CD (377–838 µg/g; n=15) compared with IBS (6–27 µg/g; n=17). Sensitivities and specificities at 50 µg/g were 94%–100% and 82%–100%, respectively. Median f-S100A12 levels were significantly higher in UC (81.0 µg/g; IQR 38.3–159.8) and CD (47.2 µg/g; IQR 5.3–108.9) compared with IBS (0.7 µg/g; IQR 0.5–0.8). At 2.8 µg/g, f-S100A12 had a sensitivity of 97% and specificity of 94%. The blood biomarkers demonstrated sensitivities and specificities of 44%–63% and 80%–92%, respectively.

Conclusions

The diagnostic sensitivity of the calprotectin assays was similar despite inter-kit variability in absolute values. There is a need for f-Cp assay standardisation, but in its absence assay-specific cut-off values may optimise their diagnostic performance. F-S100A12 demonstrated comparable sensitivity and specificity to f-Cp and although a research tool at present, may have a future role to play in the diagnosis and management of these patients.

Immune biomarkers in the spectrum of childhood noncommunicable diseases

A biomarker is an accurately and reproducibly quantifiable biological characteristic that provides an objective measure of health status or disease. Benefits of biomarkers include identification of therapeutic targets, monitoring of clinical interventions, and development of personalized (or precision) medicine. Challenges to the use of biomarkers include optimizing sample collection, processing and storage, validation, and often the need for sophisticated laboratory and bioinformatics approaches. Biomarkers offer better understanding of disease processes and should benefit the early detection, treatment, and management of multiple noncommunicable diseases (NCDs). This review will consider the utility of biomarkers in patients with allergic and other immune-mediated diseases in childhood. Typically, biomarkers are used currently to provide mechanistic insight or an objective measure of disease severity, with their future role in risk stratification/disease prediction speculative at best. There are many lessons to be learned from the biomarker strategies used for cancer in which biomarkers are in routine clinical use and industry-wide standardized approaches have been developed. Biomarker discovery and validation in children with disease lag behind those in adults; given the early onset and therefore potential lifelong effect of many NCDs, there should be more studies incorporating cohorts of children. Many pediatric biomarkers are at the discovery stage, with a long path to evaluation and clinical implementation. The ultimate challenge will be optimization of prevention strategies that can be implemented in children identified as being at risk of an NCD through the use of biomarkers.

Accuracy of Diffusion-weighted Magnetic Resonance Colonography in Assessing Mucosal Healing and the Treatment Response in Patients with Ulcerative Colitis

BACKGROUND AND AIMS

Using sigmoidoscopy as the gold standard, we assessed the accuracy, and the responsiveness to change, of diffusion-weighted magnetic resonance colonography in ulcerative colitis, using the Nancy score.

METHODS

A total of 29 ulcerative colitis patients, having undergone at least two diffusion-weighted magnetic resonance colonographies, were included. Disease activity was evaluated using the Mayo endoscopic subscore and the Nancy score. We determined the accuracy of the Nancy score in the diagnosis of mucosal healing. We also assessed its responsiveness to change in 17 patients with a Mayo endoscopic subscore of 2 or 3 at treatment initiation.

RESULTS

A total Nancy score < 7 had a sensitivity of 0.75 and a specificity of 0.67 (area under the curve: 0.72; 95% confidence interval: [0.56-0.88]; p = 0.0063) in the diagnosis of mucosal healing. The total Nancy score was sensitive to change in ulcerative colitis [Guyatt's responsiveness index: 1.8; standardised effect size ratio: 1.36]. The Nancy score was reliable [intra-class correlation coefficient: 0.63; p = 0.01]. The mean Mayo endoscopic subscore and the mean Nancy score both fell significantly in patients who achieved mucosal healing (mean ± standard deviation [SD] Mayo endoscopic subscore: 2.4 ± 0.55 at baseline and 0.6 ± 0.55 at reassessment, p = 0.02; mean Nancy score: 18.2 ± 9.1 at baseline and 3 ± 1.6 at reassessment, p = 0.006). No significant changes in Nancy score were observed in active patients at reassessment.

CONCLUSIONS

The Nancy score is a highly responsive, reliable tool for assessing treatment response in patients with ulcerative colitis. The Nancy score accurately detects mucosal healing.

Inflammatory bowel disease detection and monitoring by measuring biomarkers in non-invasively collected colorectal mucus

BACKGROUND AND AIM

Non-invasive detection and monitoring of inflammatory bowel disease (IBD) is an important clinical challenge. Stool calprotectin is the most popular among available options, but the necessity of stool collection limits its acceptability. This study aimed to evaluate biomarker measurement in non-invasively collected colorectal mucus as a new tool for IBD detection and activity monitoring.

METHODS

Calprotectin, eosinophil-derived neurotoxin (EDN), and protein S100A12 were measured in colorectal mucus self-collected following defecation by 58 patients with IBD (before therapy), 50 patients with irritable bowel syndrome, and 33 healthy volunteers. Patients with IBD also collected samples at days 10, 20, and 30 of treatment for disease activity monitoring.

RESULTS

Protein biomarker levels were significantly (P < 0.001) higher in IBD patients than in irritable bowel syndrome and control groups. Calprotectin and EDN effectively detected IBD with a respective sensitivity and specificity of 0.76 and 0.92 for calprotectin and 0.83 and 0.94 for EDN. S100A12 was less sensitive. Calprotectin and EDN results were combined in a new test (CALEDN) that had a sensitivity of 0.91 and a specificity of 0.89. Repeated biomarker measurement during IBD treatment demonstrated a steady decline of calprotectin and EDN levels as well as CALEDN values in patients responding to applied therapy and lack of this pattern in non-responders.

CONCLUSIONS

Measuring calprotectin and EDN in non-invasively collected colorectal mucus presents a simple and efficient method for IBD detection and monitoring. Excellent performance of EDN for this purpose is reported for the first time. Combining calprotectin and EDN in one test improves IBD detection sensitivity.

Fecal biomarkers in inflammatory bowel disease: how, when and why?

Over the last thirty years knowledge on fecal biomarkers (FM) has substantially increased. Nowadays these non-invasive inflammation markers are used in the daily management of inflammatory bowel disease (IBD). The interest in investigating FM was motivated by the need of a simple, quick, disposable and less invasive marker of disease activity, which might remove the need for endoscopy when following up with patients. Areas covered: Current literature was reviewed for articles regarding the role of FM in IBD diagnosis, activity, flare prediction, medication and surgical treatment response as well as how FM may differ in adult and paediatric IBD patient populations. Expert commentary: Although FM is relevant in IBD patient follow-up, there isn't enough data regarding FM reference values for different ages, different disease subtypes, disease localization/extension or response to therapy. Serial measurements of FM for each patient may be useful in accessing relapse in most patients. FM presented more consistent results when used as a predictive tool of relapse after ileocecal surgery in Crohn's disease. Ongoing research will clarify FM role in decision-making IBD daily practice.

Compliance with the faecal calprotectin test in patients with inflammatory bowel disease

BACKGROUND

We investigated, for the first time, levels of compliance with faecal calprotectin test in inflammatory bowel disease patients.

METHODS

All consecutive adult inflammatory bowel disease patients having been prescribed an faecal calprotectin test between December 2014-July 2015 were included. At their next visit to the hospital, patients had to return a stool sample for the faecal calprotectin test and answer a simple questionnaire: 'Have you brought a stool sample? If not, why not? If so, did you encounter any difficulties when collecting the sample? Were you aware of faecal calprotectin before being asked to take the test?'.

RESULTS

One hundred and one patients were included (50 men; 77 patients with Crohn's disease). The range age was 40 years (19-68). Eighty-nine patients were being treated with infliximab, 10 were on vedolizumab, and two were not being treated with a biologic. Thirty-seven patients (35%) had performed the faecal calprotectin test. Eighty-one patients (80%) had not been aware of faecal calprotectin before being asked to take the test. Of the 64 patients who did not take the test, the prime reasons for non-compliance were forgetfulness (n = 49, 76.6%), a lack of perceived benefit for the test (n = 7, 11%), constipation (n = 5, 7.8%), refusal to handle faeces (n = 2, 3.1%), and difficulty collecting the stool sample (n = 1, 1.5%).

CONCLUSION

Only one-third of the patients performed the faecal calprotectin test. The main reason for non-compliance was forgetfulness. Our present results emphasise the need for better patient education on the importance of complying with faecal calprotectin testing and the future of faecal calprotectin testing at home.

New Biomarkers for Diagnosing Inflammatory Bowel Disease and Assessing Treatment Outcomes

Despite advances in our understanding of the pathophysiology underlying inflammatory bowel disease, there remains a significant need for biomarkers that can differentiate between Crohn's disease and ulcerative colitis with high sensitivity and specificity, in a cost-efficient manner. As the focus on personalized approaches to the delivery of medical treatment increases, new biomarkers are being developed to predict an individual's response to therapy and their overall disease course. In this review, we will outline many of the existing and recently developed biomarkers, detailing their role in the assessment of patients with inflammatory bowel disease. We will identify opportunities for improvement in our biomarkers, including better differentiation between the subtypes of inflammatory bowel disease. We will also discuss new targets and strategies in biomarker development, including combining modalities to create biomarker signatures to improve the ability to predict disease courses and response to therapy among individual patients.

Fecal calprotectin for the prediction of small-bowel Crohn's disease by capsule endoscopy: a systematic review and meta-analysis

BACKGROUND AND AIMS

Fecal calprotectin is a well-established marker of mucosal inflammation. Although the correlation of elevated calprotectin levels with colonic inflammation has been confirmed repeatedly, it is less established for the small bowel. The aim of the current study was to assess the diagnostic accuracy of calprotectin for the prediction of active small-bowel disease on capsule endoscopy by performing a diagnostic test meta-analysis.

MATERIALS AND METHODS

A comprehensive search was performed using PubMed/Embase. Studies addressing patients with suspected/established Crohn's disease (CD) evaluated with calprotectin and videocapsule were included. A diagnostic meta-analysis was carried out; pooled diagnostic sensitivity, specificity, and diagnostic odds ratio (DOR) were calculated for each cut-off.

RESULTS

Seven studies (463 patients) were entered into the final analysis. The DOR was significant for all the evaluated FC cut-offs (50 μg/g: sensitivity 0.83, specificity 0.53, DOR-5.64; 100 μg/g: sensitivity 0.68, specificity 0.71, DOR-5.01; 200 μg/g: sensitivity 0.42, specificity 0.94, DOR-13.64). On sensitivity analyses, when only studies addressing suspected Crohn's or retrospective studies were included, the results did not change significantly. For studies including patients with suspected CD only, the overall accuracy for FC cut-off 50 μg/g was further increased (sensitivity 0.89, specificity 0.55, DOR-10.3), with a negative predictive value of 91.8%.

SUMMARY AND CONCLUSION

Fecal calprotectin has a significant diagnostic accuracy for the detection of small-bowel CD. Our results suggest that in patients with suspected CD with calprotectin <50 μg/g, the likelihood of positive diagnosis is very low.

Gastroenterological endpoints in drug trials for cystic fibrosis

The phenotype of cystic fibrosis includes a wide variety of clinical and biochemical gastrointestinal presentations. These gastrointestinal characteristics of the disease have come under renewed interest as potential outcome measures and clinical endpoints for therapeutic trials in cystic fibrosis. Established gastrointestinal clinical endpoints, like e.g. fecal elastase-1, are already used in trials. Other potential gastrointestinal outcome measures gather more scientific interest for evaluation in future trials. Gastrointestinal outcome measures look particularly relevant and promising for trials in CF patients with normal lung function or therapeutic studies in young children and infants. We review, the currently reported gastrointestinal effects of CFTR modulation therapies and discuss the potential of gastrointestinal outcome measures for therapeutic trials in cystic fibrosis. Pediatr Pulmonol. 2016;51:S18-S22. © 2016 Wiley Periodicals, Inc.

Capsule Endoscopy and Deep Enteroscopy in Irritable Bowel Disease

In approximately one-third of Crohn's disease patients, the disease is confined to the small bowel, inaccessible to the reach of standard endoscopy. Thorough and complete evaluation of the small bowel is crucial in such patients for the initial diagnosis, prognostication, and disease monitoring. Video capsule endoscopy and device-assisted enteroscopy have revolutionized the ability to visualize the small-bowel mucosa. This article reviews the literature pertaining to the use of capsule endoscopy and deep enteroscopy in established Crohn's disease, including the major indications, applications, and safety issues.

FOCUS: Future of fecal calprotectin utility study in inflammatory bowel disease

AIM

To evaluate the perspective of gastroenterologists regarding the impact of fecal calprotectin (FC) on the management of patients with inflammatory bowel disease (IBD).

METHODS

Patients with known IBD or symptoms suggestive of IBD for whom the physician identified that FC would be clinically useful were recruited. Physicians completed an online “pre survey” outlining their rationale for the test. After receipt of the test results, the physicians completed an online “post survey” to portray their perceived impact of the test result on patient management. Clinical outcomes for a subset of patients with follow-up data available beyond the completion of the “post survey” were collected and analyzed.

RESULTS

Of 373 test kits distributed, 290 were returned, resulting in 279 fully completed surveys. One hundred and ninety patients were known to have IBD; 147 (77%) with Crohn’s Disease, 43 (21%) Ulcerative Colitis and 5 (2%) IBD unclassified. Indications for FC testing included: 90 (32.2%) to differentiate a new diagnosis of IBD from Irritable Bowel Syndrome (IBS), 85 (30.5%) to distinguish symptoms of IBS from IBD in those known to have IBD and 104 (37.2%) as an objective measure of inflammation. FC levels resulted in a change in management 51.3% (143/279) of the time which included a significant reduction in the number of colonoscopies (118) performed (P < 0.001). Overall, 97.5% (272/279) of the time, the physicians found the test sufficiently useful that they would order it again in similar situations. Follow-up data was available for 172 patients with further support for the clinical utility of FC provided.

CONCLUSION

The FC test effected a change in management 51.3% of the time and receipt of the result was associated with a reduction in the number of colonoscopies performed.

The prognostic significance of faecal calprotectin in patients with inactive inflammatory bowel disease

BACKGROUND

Faecal calprotectin, an established biomarker used to assess mucosal inflammation, has been shown to correlate with endoscopic activity in inflammatory bowel disease (IBD). Longitudinal monitoring of faecal calprotectin, however, has rarely been employed beyond assessment of therapy response and post hoc analyses of clinical trials.

AIM

To study whether consecutive measurements of faecal calprotectin every third month are useful for monitoring patients with IBD in clinical remission.

METHODS

Patients aged 18 years or older, with a known diagnosis of IBD in clinical remission, were prospectively studied. Patients provided faecal samples every third month and were prospectively followed until the first clinical relapse or the end of the 2-year follow-up period. Measurements (EK-CAL, Bühlmann Lab. AG, Switzerland) were done at the end of the study. A Cox model with time-dependent covariates was used for analysis.

RESULTS

Among 104 patients, Crohn's disease (n = 49) and ulcerative colitis (n = 55), 37 had a relapse. A doubling of faecal calprotectin level between two consecutively collected samples was associated with a 101% increased risk of relapse (HR: 2.01; 95% CI: 1.53-2.65; P < 0.001). The relative risk of relapse attenuated with time (HR: 0.80; 95% CI: 0.75-0.86; P < 0.001), by a 20% decrease in risk of relapse per 3-month period since the sample was obtained.

CONCLUSIONS

By consecutively measuring faecal calprotectin every third month, we quantified the risk of relapse related to faecal calprotectin change and observed attenuation of the risk across time. Our data suggest that longitudinal monitoring of faecal calprotectin is informative in predicting relapse in IBD.

Correlation Between Calprotectin and Modified Rutgeerts Score

BACKGROUND

Endoscopic recurrence after surgery for Crohn's disease (CD) is high, and it has important prognostic value. Crohn's disease will recur in the majority of patients after surgery. Fecal calprotectin (FC) and lactoferrin (FL) have attracted interest in the postoperative setting for predicting relapse. We have evaluated the accuracy of FC and FL in diagnosing endoscopic recurrence (ER) using the modified Rutgeerts score (MRS) compared with the Rutgeerts score (RS).

METHODS

A series of consecutive patients who underwent ileocolonic resection for Crohn's disease were evaluated. Biomarkers, clinical indexes, and fecal markers were recorded on the day of ileocolonoscopy. ER was defined as a MRS ≥ i2b or a RS ≥ i2.

RESULTS

Ninety-nine patients were included in this prospective cohort. The median time between surgery and colonoscopy was 87.5 months (IQR, 31-137). FC and FL levels were higher in patients with ER than in those in remission (Median FC, 196.5 μg/g [IQR, 96-634 μg/g] versus 42.1 μg/g [IQR 19-91.60 μg/g; P < 0.001]; Median FL, 23.27 μg/g [IQR 8.9-47.8 μg/g] versus 2 μg/g [IQR 0.9-7.26 μg/g; P < 0.001]). Using the MRS, 34% of patients presented with ER compared with 76% if the RS was used. The RS performed worse than the MRS with a decrease in sensitivity (74% versus 48% for FC and 85% versus 55% for FL) and in NPV (91% versus 33% for FC, and 90% versus 37% for FL). Furthermore, the accuracy of the MRS was higher than that of the RS (75% versus 55%).

CONCLUSIONS

Both FC and FL proved to correlate well with endoscopic findings in the evaluation of Crohn's disease after surgery. Both markers predicted recurrence with greater accuracy when the MRS was used. Fecal markers can be used to monitor disease recurrence after intestinal resection, with patients being selected to undergo further endoscopic evaluation.

Magnetic resonance enterography versus capsule endoscopy activity indices for quantification of small bowel inflammation in Crohn's disease

BACKGROUND

Video capsule endoscopy (VCE) and magnetic resonance enterography (MRE) are the prime modalities for the evaluation of small bowel (SB) Crohn's disease (CD). Mucosal inflammation on VCE is quantified using the Lewis score (LS). Diffusion-weighted (DW) magnetic resonance imaging (MRI) allows for accurate assessment of SB inflammation without administration of intravenous contrast material. The Magnetic Resonance Index of Activity (MaRiA) and the Clermont index are quantitative activity indices validated for contrast-enhanced MRE and DW-MRE, respectively. The aim of this study was to compare the quantification of distal SB inflammation by VCE and MR-related activity indices.

METHODS

Patients with known quiescent SB CD were prospectively recruited and underwent MRE and VCE. LS, MaRIA and Clermont scores were calculated for the distal SB.

RESULTS

Both MRI-based indices significantly correlated with the LS and the Clermont index (r = 0.50, p = 0.001 and r = 0.53, p = 0.001, respectively). Both MaRIA and Clermont scores were significantly lower in patients with mucosal healing (LS < 135). The area under the curve (AUC) with both MR scores was moderate for prediction of any mucosal inflammation (LS ⩾ 135) and excellent for prediction of moderate-to-severe inflammation (LS ⩾ 790) (0.71 and 0.74 versus 0.93 and 0.91 for MaRIA and Clermont score, respectively).

CONCLUSIONS

Modest correlation between VCE- and MRE-based quantitative indices of inflammation in patients with quiescent SB CD was observed. Between-modality correlation was higher in patients with endoscopically severe disease. DW-MRE gauged by Clermont score was at least as accurate as contrast-enhanced MRE for quantification of SB inflammation.

Video capsule endoscopy in inflammatory bowel disease

Video capsule endoscopy (VCE) has evolved to become an important tool for the non-invasive examination of the small bowel, which hitherto had been relatively inaccessible to direct visualisation. VCE has been shown to play a role in monitoring the activity of small bowel Crohn’s disease and can be used to assess the response to anti-inflammatory treatment in Crohn’s disease. For those patients with Crohn’s disease who have undergone an intestinal resection, VCE has been assessed as a tool to detect post-operative recurrence. VCE may also aid in the reclassification of patients with a diagnosis of Inflammatory Bowel Disease Unclassified to Crohn’s disease. The evolution of colon capsule endoscopy (CCE) has expanded the application of this technology further. The use of CCE to assess the activity of ulcerative colitis has been described. This advance in capsule technology has also fuelled interest in its potential role as a minimally invasive tool to assess the whole of GI tract opening the possibility of its use for the panenteric assessment of Crohn’s disease. VCE is a safe procedure. However, the risk of a retained capsule is higher in patients with suspected or confirmed Crohn’s disease compared with patients having VCE examination for other indications. A retained video capsule is rare after successful passage of a patency capsule which may be utilised to pre-screen patients undergoing VCE. This paper describes the use of VCE in the assessment of inflammatory bowel disease.

Faecal Lactoferrin, Calprotectin, PMN-elastase, CRP, and White Blood Cell Count as Indicators for Mucosal Healing and Clinical Course of Disease in Patients with Mild to Moderate Ulcerative Colitis: Post Hoc Analysis of a Prospective Clinical Trial

OBJECTIVES

We evaluated the performance of blood and faecal biomarkers for differentiating between endoscopic inflammation and mucosal healing, and clinically active disease and sustained clinical remission, and determined the predictive value for a flare in patients with ulcerative colitis [UC].

METHODS

Clinical Activity Index [CAI], faecal lactoferrin [FLA], calprotectin [CAL], PMN-elastase [PMN-e], C-reactive protein [CRP], white blood cells [WBC], Endoscopic Index [EI], and UC-Disease Activity Index [DAI] were determined repeatedly during 12 months and at acute flares.

RESULTS

Of 91 patients [45 female; mean age 48.1±13.4 years] entering in remission, 42 [46%] patients developed a clinical flare. A total of 529 CAI and 179 EI assessments were performed. Median levels for active disease confirmed by EI [n = 35] vs clinical remission with endoscopic inflammation [n = 37] vs mucosal healing [n = 107] for FLA were 44/37/4 µg/g, CAL 25/20/10 µg/g [both p < 0.0001], PMN-e 0.06/0.03/0.02 µg/g, CRP 0.7/0.2/0.2mg/dl [both p < 0.001], and WBC 7.0/6.5/6.4/nl [p = 0.1]. There was no difference for any of the markers for defining mucosal healing by EI = 0 vs EI = 1 with the exception of PMN-e [p = 0.03], where the difference was very small and with questionable clinical relevance. Using manufacturers' cut-offs, only FLA at baseline was associated with a significant higher relative risk [RR] of flaring [RR 1.69; p = 0.018]. Using optimised cut-offs, CAL, PMN-e, and CRP were also predictive of a flare.

CONCLUSIONS

Faecal biomarkers FLA, CAL, and PMN-e were able to distinguish between UC patients with mucosal healing from clinical remission and mild disease, showed significant correlations with endoscopy, and were predictive of a flare.

Predicting durable response or resistance to antitumor necrosis factor therapy in inflammatory bowel disease

Monoclonal antibodies to tumor necrosis factor (TNF) have become a mainstay of the therapeutic armamentarium in inflammatory bowel disease (IBD) over the last 15 years. Although highly effective, primary and secondary nonresponse are common and associated with poor clinical outcomes and significant costs. Multiple clinical, genetic and immunopharmacological factors may impact the response to anti-TNFs. Early stratification of IBD patients by the expected risk of therapeutic failure during the induction and maintenance phases of treatment may allow for treatment optimization and potentially optimal short- and long-term outcomes. The aim of this review is to summarize the current data concerning the potential predictors of therapeutic success and failure of anti-TNFs in IBD.

Progress in the treatment and outcome of pediatric inflammatory bowel disease patients

INTRODUCTION

The number of pediatric patients with inflammatory bowel disease (IBD), namely Crohn´s disease, ulcerative colitis and unclassified colitis, has rapidly increased in Western countries. Areas covered: This review discusses how the treatment of pediatric IBD patients has improved,with attention given to therapeutic quality and cost. The literature search covers Medline-PubMed and the Cochrane Library, with February 2016 as the last search dates. Similarly to what has been the trend in the management of adult IBD, pediatric IBD therapy has become more active than before. High use of immunosuppressants and the availability of biological therapeutic agents has helped to control the extensive and aggressive course of pediatric IBD. Full disease control at an early phase has advantages such as preserving normal child growth and development, maintaining overall good health and quality of life, as well as decreasing the psychosocial burden of the disease. Expert commentary: A key research direction is to tailor treatment modalities according to anticipated individual phenotype and disease course. Another is to reduce healthcare costs by decreasing the so-far high rate of surgery of pediatric IBD patients, and, instead, to develop a more active approach to treatment than before.

The Impact of Magnetic Resonance Enterography and Capsule Endoscopy on the Re-classification of Disease in Patients with Known Crohn's Disease: A Prospective Israeli IBD Research Nucleus (IIRN) Study

BACKGROUND AND AIMS

The classification of Crohn's disease (CD) is usually determined at initial diagnosis and is frequently based on ileocolonoscopic and cross-sectional imaging data. Advanced endoscopic and imaging techniques such as small-bowel video capsule endoscopy (VCE) and magnetic resonance enterography (MRE) may provide additional data regarding disease extent and phenotype. Our aim was to examine whether VCE or MRE performed after the initial diagnosis may alter the original disease classification.

METHODS

Consecutive patients with known small-bowel CD in clinical remission or mild disease were prospectively recruited and underwent MRE and VCE (if small-bowel patency was confirmed by a patency capsule (PC). Montreal classifications before and after evaluation were compared.

RESULTS

Seventy-nine patients underwent MRE and VCE was performed in 56. Previously unrecognized disease locations were detected with VCE and MRE in 51 and 25%, respectively (p < 0.01) and by both modalities combined in 44 patients (55%). Twenty-two patients (27%) were reclassified as having an advanced phenotype (B2/B3). MRE and VCE reclassified the phenotype in 26 and 11% of cases, respectively (p < 0.05). Overall, both modalities combined altered the original Montreal classification in 49/76 patients (64%).

CONCLUSION

VCE and MRE may lead to reclassification of the original phenotype in a significant percentage of CD patients in remission. VCE was more sensitive for detection of previously unrecognized locations, while MRE was superior for detection of phenotype shift. The described changes in the disease classification may have an important impact on both clinical management and long-term prognosis in these patients.

Quality of Life Is Related to Fecal Calprotectin Concentrations in Colonic Crohn Disease and Ulcerative Colitis, but not in Ileal Crohn Disease

To formulate therapy goals, we aimed to define the relationship between fecal calprotectin and health-related quality of life in inflammatory bowel diseases (IBDs). This retrospective single-center cross-sectional study included ambulatory IBD patients who had completed standardized questionnaires comprising items of health-related quality of life (Short Inflammatory Bowel Disease Questionnaire) and clinical disease activity scores, and who had provided stool samples for calprotectin determination within 30 days of questionnaire completion. Correlation analyses were performed between the indicated parameters. Post hoc analysis was conducted, taking into account only data from patients with fecal calprotectin concentrations measured within 3 days of questionnaire completion. One hundred ninety-seven patients with Crohn disease and 111 patients with ulcerative colitis were enrolled in the study. Lower fecal calprotectin concentrations were associated with better health-related quality of life. The correlations were weak, but stronger if only fecal calprotectin concentrations measured within 3 days of questionnaire completion were included (results for 3 days; Crohn disease: n = 86, rS = -0.419, P < 0.001; ulcerative colitis: n = 43, rS = -0.432, P = 0.004). In Crohn disease, a significant correlation between fecal calprotectin concentration and health-related quality of life was found in patients with colonic involvement (n = 59, rS = -0.470, P < 0.001), but not in patients with purely ileal disease (n = 27, rS = -0.268, P = 0.18). Correlations between fecal calprotectin concentrations and clinical disease activity were also only weak to moderate. Owing to its moderate correlation with fecal calprotectin concentrations in IBD patients with colonic involvement, health-related quality of life should be used in combination with other markers for IBD management. This is even more important in isolated ileal Crohn disease, where no significant correlation between fecal calprotectin concentration and health-related quality of life was found. Especially for use in research studies, care should be taken to keep the time between clinical evaluation of IBD patients and the determination of fecal calprotectin concentrations as short as possible.

Enrichment of Circulating and Mucosal Cytotoxic CD8+ T Cells Is Associated with Postoperative Endoscopic Recurrence in Patients with Crohn's Disease

BACKGROUND AND AIMS

Evidence from mouse colitis models indicates that cytotoxic CD8+ T cells [CTL] play a key role in the initiation of gut lesions. We investigated whether changes in CD8+ CTL in blood or lamina propria [LP] of the neoterminal ileum were associated with postoperative endoscopic recurrence of Crohn's disease [CD].

METHODS

A total of 37 CD patients with ileocolonic resection were endoscopically followed up at 6 and 12 months post-surgery. CD8+ T cells were analysed by flow cytometry in blood and ileal LP.

RESULTS

Granzyme B- and perforin-producing CD8+ T cells were significantly increased at 6 months in blood and in ileum LP in patients with endoscopic recurrence, as compared with those in remission. At a cutoff point of 45% of CD8+ CTL, the overall accuracies of the frequency of blood granzyme B+ or perforin+ CD8+ T cells to identify patients with postoperative endoscopic recurrence were 77% and 83%, respectively. Interestingly, patients with endoscopic recurrence at 12 months were those showing the highest mucosal CD8+ CTL frequency at 6 months, while still in remission.

CONCLUSIONS

Enrichment of cytotoxic CD8+ T cells in blood and ileal mucosa coincides with CD postoperative endoscopic recurrence. This underscores that CD8 CTL may play a pathophysiological role in the initiation of gut lesions during CD.