Fecal biomarkers in the diagnosis and monitoring of Crohn's disease

The Specific Changes of Urine Raman Spectra Can Serve as Novel Diagnostic Tools for Disease Characteristics in Patients with Crohn’s Disease

Purpose

Crohn’s disease (CD) is a chronic recurrent intestinal inflammatory disease that requires repeated invasive examinations. Convenient and noninvasive diagnostic tools for CD are lacking. Surface-enhanced Raman spectroscopy (SERS) can rapidly provide specific metabolite information in various samples. Our previous study has showed urine Raman spectrum can distinguish CD patients from healthy controls noninvasively. In this study, we further investigated the value of urine Raman spectra on identifying the disease characterizations in patients with CD.

Patients and Methods

Urine samples were analyzed by SERS to acquire specific changes of the spectra from 100 active CD (aCD) patients and 88 inactive CD (iCD) patients. The accuracy of classifier models yielded by SERS was assessed by principal component analysis and support vector machine (PCA-SVM) to investigate spectral differences and disease characterizations.

Results

Given a panel of 16 specific Raman spectra, the classifier model was established to predict disease activity between patients with aCD and iCD and achieved higher efficacy than fecal calprotectin (AUC value, 0.864 vs 0.596, P=0.02). After leave-one-patient-out cross-validation, the classifier model still obtained 75.5% of accuracy. The correlation analysis showed it had negative correlation with endoscopic results (r=−0.616, P<0.0001). We further established the classifier model in identifying disease location to discriminate colonic-type from ileal-type CD with 63.6% of accuracy with the significantly increased intensity of 1643 cm⁻¹ band, and the model to predict the spectra changes of before and after treatment in tumor necrosis factor inhibitor responders with 91.2% of accuracy with a panel of 11 specific spectra. The metabolic changes of amino acids, proteins, lipids, and other compounds in urine levels were noted by SERS in patients with CD.

Conclusion

The specific changes of urine Raman spectra can reflect changes in urine metabolism. It has the potential value on being the promising diagnostic tool for disease characterizations in CD patients by a convenient and noninvasive way.

Antimicrobial peptides in hidradenitis suppurativa: a systematic review

BACKGROUND

Hidradenitis suppurativa (HS) is a chronic, inflammatory skin disease of the hair follicle defined by recurrent nodules, tunnels and scarring involving the intertriginous regions. HS is associated with microbial dysbiosis and immune dysregulation. In HS, an increasing number of studies have investigated antimicrobial peptides (AMPs).

OBJECTIVES

To provide an overview of the literature on AMPs in HS, and to discuss the potential role of AMPs in the pathogenesis of HS.

METHODS

PubMed, Embase and the Cochrane Library were searched. The titles, abstracts and full texts of all articles were manually screened. Additionally, the reference lists of the included articles were screened and hand searched for relevant studies.

RESULTS

The final literature sample comprised 18 retrospective and prospective studies (no reviews or commentaries) published between 2009 and 2020.

CONCLUSIONS

This review demonstrates the multitude of AMPs in HS. Although the methodology of the studies varied, the included studies indicate a consistent overexpression of human β-defensin (hBD)-2, S100A7, S100A8 and S100A9 at both the mRNA and protein levels, and a decreased expression of hBD-1. Overall, the studies point to a dysregulation of AMPs in both lesional and nonlesional HS skin.

The utility of faecal and urine biomarkers for small bowel diseases

PURPOSE OF REVIEW

Small bowel diseases pose a unique diagnostic and management challenge and often requires tertiary specialist referral. The use of biomarkers may provide a cheap, noninvasive tool to assess the small bowel in terms of diagnosis, offering a better way to triage referrals and select patients for early management. This review looks at the most recent evidence behind the use of several faecal and urine biomarkers for small bowel diseases.

RECENT FINDINGS

Faecal calprotectin shows the most promise, with evidence to support its role in predicting relapse postsurgery and monitoring treatment response in patients with Crohn's disease. A faecal calprotectin less than 50 μg/g may also be used as a cut-off to triage further investigation. Faecal lactoferrin also appears promising as a marker of small bowel inflammation. A positive faecal immunohistochemistry test precapsule may help to prioritize referrals for obscure bleeding.

SUMMARY

The use of biomarkers in the diagnosis and management of small bowel disease is still controversial and remains unclear. More studies are required to further develop their potential and before societal guidelines can be developed to direct their appropriate use in clinical practice.

Association of clinical characteristics and lifestyle factors with fecal S100/calgranulin concentrations in healthy dogs

Background

Fecal S100/calgranulin (S100A12 and calprotectin) concentrations are useful markers of gastrointestinal inflammation in dogs. In people, fecal S100/calgranulin concentrations are affected by age, obesity, diet and other lifestyle factors. Knowledge about the effects of such factors on fecal S100/calgranulin concentrations in dogs is currently scarce.

Objective

To evaluate the association between several factors and fecal S100/calgranulin concentrations in a large cohort of healthy adult dogs.

Methods

Single‐spot fecal samples from 181 healthy pet dogs and data derived from a standard questionnaire served to evaluate the effect of age, sex, reproductive status, body weight and body condition, breed type and size, vaccination, endoparasite treatment, diet, environment and travel history on fecal S100/calgranulin concentrations and the fecal calgranulin ratio (fCalR).

Results

Univariate analysis showed a significant association of reproductive status (in female dogs) and breed size with fecal S100A12, fecal calprotectin and fCalR. Breed type was linked to fecal S100A12 concentrations and fCalR; recent vaccination (particularly with a vaccine against canine parvovirus) to fCalR. In multivariate models, breed size was linked to fecal S100A12 and calprotectin concentrations, and recent vaccination affected S100A12 concentrations.

Conclusions

Breed size, recent vaccination and reproductive status in female dogs can affect fecal S100/calgranulin concentrations, and these biomarkers should be interpreted in light of those confounding factors. The utility of reference intervals for fecal canine S100/calgranulin concentrations might be improved through stratification by sex/reproductive status and breed size. Fecal canine S100/calgranulin concentrations are not confounded by age, body condition, deworming, diet, environment or travel history.

Monitoring Inflammatory Bowel Disease in Pregnancy Using Gastrointestinal Ultrasonography

BACKGROUND AND AIMS

Inflammatory bowel disease [IBD] affects women during their childbearing years. Gastrointestinal ultrasonography [GIUS] accurately identifies disease activity in non-pregnant patients with IBD. The utility of GIUS in pregnancy has not been established. We aimed to determine the feasibility and accuracy of GIUS in the assessment of IBD during pregnancy progression.

METHODS

A multicentre observational study of women with IBD undergoing GIUS during pregnancy. Clinicians assessed the adequacy of bowel views and disease activity in four colonic segments and the terminal ileum. Location[s] in which views were impeded by the uterus were documented. GIUS disease activity [bowel wall thickness >3 mm] was compared with biochemical disease activity [faecal calprotectin >100 μg/g].

RESULTS

Ninety patients and 127 GIUS examinations were included [median gestation 19 weeks, range 4-33]. Adequate colonic views were obtained in 116/127 [91%] scans. Adequate ileal views were obtained in 62/67 [93%] scans <20 weeks and 30/51 [59%] scans at 20-26 weeks. There was a positive correlation between bowel wall thickness and calprotectin [r = 0.26, p = 0.03]. GIUS delivered a specificity of 83%, sensitivity of 74%, and negative predictive value of 90% compared with calprotectin.

CONCLUSIONS

GIUS is a feasible and accurate modality for monitoring IBD in pregnancy. Adequate GIUS views of the colon and terminal ileum can be obtained in the majority of patients up to 20 weeks of gestation. Beyond 20 weeks, GIUS provides good views of the colon but the terminal ileum becomes difficult to assess.

Utility of bowel ultrasound in assessing disease activity in Crohn's disease

BACKGROUND

Gastrointestinal ultrasound (GIUS) has been used increasingly for monitoring inflammatory bowel disease (IBD) patients. The aim of this study was to assess the utility of GIUS in assessing disease activity in Crohn's disease (CD).

METHODS

Consecutive patients with CD (diagnosis established for at least 6 months) between July 2017 and July 2018 requiring assessment of disease activity were prospectively assessed by magnetic resonance enterography, colonoscopy (CS), and GIUS within a 2-week period and without any change in ongoing treatment. Features on GIUS which correlated with disease activity were assessed. Sensitivity and specificity of the GIUS in assessing disease activity and localization were calculated.

RESULTS

Thirty-five patients were enrolled in the study. Bowel wall thickness (BWT) ≥ 3 mm and Doppler activity ≥ 2 had the highest sensitivity (100% and 95.6%, respectively) for detecting active disease on CS. BWT ≥ 3 mm had sensitivity, specificity, positive predictive value, and negative predictive value of 100%, 83.3%, 92%, and 100%, respectively for assessing active disease. Combination of median BWT, Doppler activity, and loss of bowel wall stratification correlated with simplified endoscopic score (SES) for CD (r = 0.8, p 0.009) and Harvey-Bradshaw index (HBI, r = 0.76, p 0.04). For localizing active disease in the ileum, GIUS had a sensitivity of 93.7%, 80% for lesions in the right colon, 100% for transverse colon, and 89% for the left colon. Specificity was 100% for ileal and colonic lesions.

CONCLUSION

Loss of stratification, BWT, and Doppler activity in the bowel wall correlate with endoscopic and clinical disease activity in CD. GIUS is a sensitive modality in assessing disease activity in CD.

Early serum infliximab trough level and mucosal healing could be predictors for one-year outcome after initiating therapy in Crohn's disease

BACKGROUND AND AIMS

Serum infliximab trough level(S-IFX) and antibody were documented to correlate with clinical response. The aim of this study was to identify the relationship between early S-IFX, early mucosal healing (MH) and one-year outcome in a cohort on maintenance IFX therapy in Crohn's disease (CD).

METHODS

The study group comprised of retrospectively enrolled patients diagnosed for Crohn's disease (n = 108). Patients received scheduled maintenance therapy after response to IFX induction, and had undergone the early S-IFX test and endoscopic examination at week 14. Clinical outcomes were evaluated during maintenance therapy until week 52.

RESULTS

Early S-IFX was 4.78 ± 6.16 ug/ml in all the patients and 19% (21/108) of them developed antibodies, and 52 patients reached early MH. During 52 weeks' follow-up. Twenty-eight percent (30/108) of patients showed loss of response to IFX. Patients who lost response had lower early S-IFX than those who had sustained response (3.01 ± 3.66 vs. 5.47 ± 6.79 ug/ml, p = .02; 48 vs. 23%, p =  .02). At week 52, 73 patients had repeated endoscopy and 42% of them reached MH. Early S-IFX had a predictive value on MH at week 52. When early S-IFX > 2.5 ug/ml, the sensitivity for predicting MH at week 52 was 87%, and the specificity were 61% (AUC = 0.73, p < .01). The combined predictive value of early S-IFX and early MH became stronger. Only 6% (1/18) of those patients who had low early S-IFX and had not reached early MH could reach MH at week 52.

CONCLUSIONS

Early S-IFX and early MH could predict one-year response after initiating IFX therapy in Crohn's disease.

Fecal Markers of Inflammation and Disease Activity in Pediatric Crohn Disease: Results from the ImageKids Study

BACKGROUND

Noninvasive and accurate methods to monitor inflammatory bowel disease are required. As a planned ancillary study of the prospective ImageKids cohort, we aimed to assess the performance of fecal calprotectin (FC) with comparison to 3 fecal inflammatory markers; S100A12 (FA12), tumor pyruvate kinase isoenzyme type M2 (FM2PK) and fecal osteoprotegerin (FOPG) as indicators of a number of disease characteristics.

METHODS

The ImageKids study was a multicenter study designed to develop 2 magnetic resonance enterography-based measures for children with Crohn disease (6-18 years old). All patients underwent magnetic resonance enterography, a complete ileocolonoscopic evaluation and provided a fecal sample. Fecal samples were assay for FC, FA12, FM2PK, and FOPG by ELISA.

RESULTS

One-hundred fifty-six children provided 190 fecal samples. Median (interquartile range) for fecal makers were FC, 602 (181-1185) μg/g; FA12, 21 (3-109) μg/g; FM2PK, 16 (2-20) U/mL; and FOPG, 125 (125-312) μg/g. All markers correlated with simple endoscopic severity index for Crohn disease and with other constructs of disease activity, but FC had the highest overall correlations. FA12, however, predicted mucosal healing with significantly higher specificity (87% vs 70%, P = 0.004) and equivalent sensitivity (91% vs 90%) compared to FC.

CONCLUSION

This study has confirmed that FC is useful, and overall best, marker to monitor mucosal inflammation in inflammatory bowel disease. FA12, however, appears to be a more suitable maker for prediction of mucosal healing in children.

Fecal lactoferrin accurately reflects mucosal inflammation in inflammatory bowel disease

BACKGROUND

Studies have demonstrated a potential role for fecal biomarkers such as fecal calprotectin (FC) and fecal lactoferrin (FL) in monitoring inflammatory bowel diseases (IBD) - Crohn’s disease (CD) and ulcerative colitis (UC). However, their correlation to endoscopic scores, disease severity and affected intestinal surface has not been extensively investigated.

AIM

To correlate FL, and for comparison white blood cell (WBC) and C-reactive protein (CRP), with endoscopic scores, disease extent and location in CD and UC.

METHODS

Retrospective analysis in 188 patients who had FL, CRP and WBC determined within 30 d of endoscopy. Disease location, disease extent (number of intestinal segments involved), disease severity (determined by endoscopic scores), timing of FL testing in relation to colonoscopy, as well as the use of effective fast acting medications (steroids and biologics) between colonoscopy and FL measurement, were recorded.

RESULTS

In 131 CD and 57 UC patients, both CRP and FL - but not WBC - distinguished disease severity (inactive, mild, moderate, severe). In patients receiving fast-acting (steroids or biologics) treatment in between FL and colonoscopy, FL showed a higher correlation to endoscopic scores when tested before vs after the procedure (r = 0.596, P < 0.001, vs r = 0.285, P = 0.15 for the Simple Endoscopic Score for CD; and r = 0.402, P = 0.01 vs r = 0.054 P = 0.84 for Disease Activity Index). Finally, FL was significantly correlated with the diseased mucosal surface (colon-ileocolon > small bowel) and the number of inflamed colon segments.

CONCLUSION

FL and CRP separated disease severity categories with FL showing lower discriminating P-values. FL showed a close correlation with the involved mucosal surface and with disease extent and was more closely correlated to endoscopy when determined before the procedure – this indicating that inflammatory activity changes associated with therapy might be rapidly reflected by FL levels. FL can accurately and timely characterize intestinal inflammation in IBD.

I_MDS: an inflammatory bowel disease molecular activity score to classify patients with differing disease-driving pathways and therapeutic response to anti-TNF treatment

Crohn’s disease and ulcerative colitis are driven by both common and distinct underlying mechanisms of pathobiology. Both diseases, exhibit heterogeneity underscored by the variable clinical responses to therapeutic interventions.

We aimed to identify disease-driving pathways and classify individuals into subpopulations that differ in their pathobiology and response to treatment.

We applied hierarchical clustering of enrichment scores derived from gene set variation analysis of signatures representative of various immunological processes and activated cell types, to a colonic biopsy dataset that included healthy volunteers, Crohn’s disease and ulcerative colitis patients. Patient stratification at baseline or after anti-TNF treatment in clinical responders and non-responders was queried. Signatures with significantly different enrichment scores were identified using a general linear model. Comparisons to healthy controls were made at baseline in all participants and then separately in responders and non-responders. Fifty-nine percent of the signatures were commonly enriched in both conditions at baseline, supporting the notion of a disease continuum within ulcerative colitis and Crohn’s disease. Signatures included T cells, macrophages, neutrophil activation and poly:IC signatures, representing acute inflammation and a complex mix of potential disease-driving biology. Collectively, identification of significantly enriched signatures allowed establishment of an inflammatory bowel disease molecular activity score which uses biopsy transcriptomics as a surrogate marker to accurately track disease severity. This score separated diseased from healthy samples, enabled discrimination of clinical responders and non-responders at baseline with 100% specificity and 78.8% sensitivity, and was validated in an independent data set that showed comparable classification. Comparing responders and non-responders separately at baseline to controls, 43% and 70% of signatures were enriched, respectively, suggesting greater molecular dysregulation in TNF non-responders at baseline. This methodological approach could facilitate better targeted design of clinical studies to test therapeutics, concentrating on patient subsets sharing similar underlying pathobiology, therefore increasing the likelihood of clinical response.

Patients exhibiting similar phenotypical characteristics, diagnosed with the same disease, exhibit variable response to therapeutics. This is a major health care issue, due to the increased patient suffering and the socioeconomical burden that occurs. Crohn’s disease and ulcerative colitis constitute good examples of inflammatory conditions, with sufferers responding differentially to existent therapeutics. Here, we identified disease-driving pathways and classified individuals into subpopulations that differ in their pathobiology and response to treatment. We utilized gene set variation analysis and transcriptomic data from inflammatory bowel disease sufferers to stratify patients at baseline or after anti-TNF treatment in clinical responders and non-responders. We explored gene signatures obtained from the literature, relevant to immune processes, which were significantly enriched in disease compared to healthy controls, as well as before and after treatment. Using these signatures, we established an inflammatory bowel disease molecular activity score, which allowed us to separate clinical responders and non-responders at baseline with high specificity and sensitivity. We validated the proposed approach in an independent data set, demonstrating comparable classification. This methodological approach may lead to better targeted design of clinical studies, allowing the selection of patient sharing similar underlying pathobiology, thus increasing the likelihood of clinical response to treatment.

Update on C-reactive protein and fecal calprotectin: are they accurate measures of disease activity in Crohn's disease?

'Treat-to-target' paradigms in Crohn's disease (CD) directed at suppressing intestinal inflammation require accurate and reliable measures of disease activity. Although endoscopy has traditionally been considered a gold standard, cost, complexity, resource limitations, and invasiveness are important limitations. Hence, substantial interest exists for non-invasive serum and fecal biomarkers, namely C-reactive protein (CRP) and fecal calprotectin (FC), in the diagnosis, monitoring, and treatment of CD. Areas covered: We review the evidence for using serum CRP and FC in distinguishing patients with CD from those with irritable bowel syndrome, categorizing disease activity among patients with an established diagnosis of CD, predicting the likelihood of treatment response, identifying asymptomatic patients in medically or surgically induced remission who are at risk for disease relapse, and as treatment targets. Expert commentary: Accurate interpretation of CRP and FC is dependent on several factors including the clinical context, the performance characteristics of the assay, the specified test cut-offs, and the pre-test probability of disease. Emerging evidence indicates that CRP and FC are valuable adjuncts for the management of CD in specific circumstances described in this review.

Reference intervals for stool calprotectin in preterm neonates and their utility for the diagnosis of necrotizing enterocolitis

OBJECTIVE

Calprotectin is an antimicrobial protein found in stool when released by granulocytes. We sought to create stool calprotectin reference ranges in preterm neonates and to evaluate whether levels exceeding the upper reference interval are diagnostic for necrotizing enterocolitis (NEC).

STUDY DESIGN

Stool calprotectin was measured in premature neonates without gastrointestinal pathology to create reference intervals. For comparison, levels from infants undergoing "rule out NEC" evaluations were plotted on these reference intervals.

RESULTS

Stool calprotectin reference intervals were created according to gestational age at birth and corrected gestational age. Levels during "rule out NEC" evaluations were more often above the upper reference interval with NEC vs. those without NEC.

CONCLUSIONS

Stools from preterm neonates have a higher range of calprotectin than stools from healthy term neonates. In evaluating preterm neonates for NEC with stool calprotectin, a calprotectin upper reference interval that incorporates corrected gestational age best predicts the diagnosis of NEC.

A Distinctive Urinary Metabolomic Fingerprint Is Linked With Endoscopic Postoperative Disease Recurrence in Crohn's Disease Patients

BACKGROUND

Crohn's disease (CD) patients who undergo ileocolonic resection frequently have disease recurrence. The aim of this preliminary study was to identify urinary metabolomic profiles associated with disease recurrence in order to identify underlying mechanisms of recurrence and possible disease biomarkers.

METHODS

Biopsies from the neoterminal ileum were collected from CD patients (n = 38) after ileocolonic resection in order to assess mucosa-associated microbiota using 16S rRNA multitag pyrosequencing. Urine samples were collected, and metabolomic profiling was done using high-resolution nuclear magnetic resolution spectroscopy and a combined direct infusion liquid chromatography tandem mass spectrometry. The Rutgeerts scoring system was used to assess endoscopic postoperative recurrence of CD.

RESULTS

There were 28 (73.7%) patients with endoscopic CD recurrence. CD patients who were in endoscopic remission had a higher abundance of Bacteroidetes and lower abundance of Fusobacteria and Proteobacteria in comparison with CD patients who had endoscopic recurrence. In addition, metabolomic profiling could also discriminate between these 2 groups of patients. Endoscopic recurrence was associated with increased concentration of urinary levoglucosan. Rutgeerts score was positively correlated with levoglucosan and propylene glycol levels.

CONCLUSIONS

CD patients who present with endoscopic disease recurrence after surgery have a unique urinary metabolomic fingerprint that can differentiate them from CD patients who are in endoscopic remission after ileocolonic resection. In addition, mucosal-associated microbiota in CD patients with or without disease recurrence after surgery differs and correlates with some urinary metabolites.

Non-invasive identification of protein biomarkers for early pregnancy diagnosis in the cheetah (Acinonyx jubatus)

Approximately 80% of cheetahs living in typical zoological collections never reproduce. In more than 60% of breedings, the female is confirmed to ovulate, but parturition fails to occur. It is unknown if these non-pregnant intervals of elevated progesterone (deemed luteal phases) are conception failures or a pregnancy terminating in embryonic/fetal loss. There have been recent advances in metabolic profiling and proteome analyses in many species with mass spectrometry used to identify ‘biomarkers’ and mechanisms indicative of specific physiological states (including pregnancy). Here, we hypothesized that protein expression in voided cheetah feces varied depending on pregnancy status. We: 1) identified the expansive protein profile present in fecal material of females; and 2) isolated proteins that may be candidates playing a role in early pregnancy establishment and diagnosis. Five hundred and seventy unique proteins were discovered among samples from pregnant (n = 8), non-pregnant, luteal phase (n = 5), and non-ovulatory control (n = 5) cheetahs. Four protein candidates were isolated that were significantly up-regulated and two were down-regulated in samples from pregnant compared to non-pregnant or control counterparts. One up-regulated candidate, immunoglobulin J chain (IGJ; an important component of the secretory immune system) was detected using a commercially available antibody via immunoblotting. Findings revealed that increased IGJ abundance could be used to detect pregnancy successfully in >80% of 23 assessed females within 4 weeks after mating. The discovery of a novel fecal pregnancy marker improves the ability to determine reproductive, especially gestational, status in cheetahs managed in an ex situ insurance and source population.

Ustekinumab to treat Crohn's disease

Ustekinumab is a monoclonal antibody directed against the p40 subunit, which is part of interleukins IL-12 and IL-23. The efficacy of ustekinumab versus placebo in terms of clinical response and remission of induction has been shown in phase3 clinical trials. When used as subcutaneous maintenance therapy, the therapeutic benefit of ustekinumab over placebo has been confirmed in both clinical response and remission in patients who have responded clinically to induction therapy. In addition, ustekinumab has demonstrated an improvement in mucosal healing parameters. The safety profile of the drug has been good, with low infection rates (without reactivation of tuberculosis) and absence of tumour reporting. The development of drug immunogenicity appears to be rare. In summary, ustekinumab is a promising treatment option in patients with Crohn's disease, as an alternative to anti-TNFα drugs.

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.

Increased Intestinal Permeability in Relatives of Patients With Crohn's Disease Is Not Associated With Small Bowel Ulcerations

BACKGROUND & AIMS

Many first-degree relatives of patients with Crohn's disease (CD) have increased intestinal permeability. Video capsule endoscopy (VCE) is the most sensitive imaging test to identify small bowel mucosal lesions that could indicate subclinical CD. We aimed to estimate the association of increased intestinal permeability with small bowel ulcerations detectable by VCE in healthy first-degree relatives of patients with CD.

METHODS

We conducted a cross-sectional study of 223 healthy, asymptomatic first-degree relatives of patients with CD (parents, siblings, and children; 9-45 years old) enrolled at the University of Alberta between 2009 and 2012. Patients were given the lactulose and mannitol test to measure small bowel permeability; we used high-performance liquid chromatography to measure concentrations of lactulose and mannitol in urine samples (increased permeability defined as a ratio of lactulose/mannitol 0.025 or greater). Patients with increased permeability (n = 39) and randomly selected subjects with normal permeability (n = 59) were then examined by VCE for signs of small bowel inflammation and subclinical CD. The prevalence of small bowel lesions was compared among groups. We performed logistic regression analyses to estimate odds ratios for the association of small bowel ulcerations with intestinal permeability.

RESULTS

Among 223 first-degree relatives of patients with CD, 30% were found to have increased intestinal permeability; VCE examination found 24% of subjects to have 3 or more small bowel ulcers. Three or more small bowel ulcers were detected in 28% of patients with increased intestinal permeability and 20% of patients with normal intestinal permeability (P = .37). The adjusted odds ratio for the association of 3 or more small bowel ulcers with increased intestinal permeability was 1.5 (95% confidence interval, 0.6-3.8; P = .46).

CONCLUSIONS

Thirty percent of healthy, asymptomatic first-degree relatives of patients with CD have increased intestinal permeability. However, a strong association of small bowel ulceration seen on VCE with increased intestinal permeability was not observed.

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.

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.

Normative Fecal Calprotectin Concentrations in Guatemalan Preschoolers Are High Relative to Children Reported Elsewhere

BACKGROUND

Calprotectin is a fecal marker of intraintestinal inflammation derived from activated enteric neutrophils and macrophages. It is useful as a clinical marker in inflammatory bowel diseases; furthermore, it may have a role in public health epidemiology.

OBJECTIVES

The aim of the study was to describe the distribution of fecal calprotectin in Guatemalan preschool children sharing a common institutional diet; to relate it collectively to pediatric distributions in other geographic settings, and individually to concomitant indicators of intestinal infection or colonization and other descriptive features of the child.

METHODS

Fecal samples were collected in 87 subjects, ages 2 to 7 years across 3 daycare centers sharing a common institutional menu, but from different ecological settings. Stools were examined, variously by routine light microscopy, quantitative egg counts, and a Giardia antigen test, for microbiological diagnosis, and an ELISA assay for fecal calprotectin (CalproLab).

RESULTS

The median fecal calprotectin value was 58 mg/kg, with a mean of 98 ± 136 mg/kg and a range from 10 to 950 mg/kg; 61% of values were above the manufacturer's cut-off for elevated concentration and 51% exceeded an age-adjusted criterion. There were no associations between sex, age, growth indicators, or fecal microbiological findings by microscopy or ELISA assays, alone or in combination. The central tendency (mean or median) and distribution were generally shifted to the right in relation to comparable reports from children across the world literature.

CONCLUSIONS

Although specific, low-grade intestinal infections do not define calprotectin subgroups, right-shifted fecal calprotectin status in this population may reflect a general and diffuse stress of adverse environmental sanitation.

Utility of Biomarkers in the Management of Inflammatory Bowel Disease

OPINION STATEMENT

Inflammatory bowel disease (IBD) is comprised of complex clinical and pathological conditions. It runs a chronic course, and proper management requires constant monitoring of disease activity. Recent evidence suggests that subjective patient scores have a poor correlation with disease activity. Endoscopy remains the gold standard for diagnosing and monitoring disease activity. As healthcare is moving towards less costly and less invasive treatments, the need for biomarkers in the management of IBD is evident. Over the last decade, several biomarkers have been found, which may correct the discrepancy between subjective patient scores and the need for endoscopy.

Accuracies of fecal calprotectin, lactoferrin, M2-pyruvate kinase, neopterin and zonulin to predict the response to infliximab in ulcerative colitis

BACKGROUND

Fecal markers might predict the response to anti-TNFα in ulcerative colitis (UC).

AIMS

To compare the performance of fecal calprotectin (fCal), lactoferrin (fLact), M2-PK (fM2-PK), neopterin (fNeo), and zonulin (fZon) to predict the response to therapy in active UC patients.

METHODS

Disease activity from 31 consecutive patients with an active UC, treated with infliximab (IFX) was assessed by the Mayo score at baseline and at week 14 and by the partial Mayo score at W52 and stool samples collected for fecal marker measurements at W0, W2, and W14.

RESULTS

At W14, 19 patients (61%) were responders to IFX induction. The median levels of fCal, fLact and fM2-PK drop dramatically from baseline to W14 in clinical responders. At W2, fM2-PK, fLact and fCal levels predicted accurately the response to IFX induction. At W14, fLact, fCal, and fM2-PK were individually reliable markers to predict sustained response at W52. The performances of fNeo and fZon were weaker in this setting.

CONCLUSIONS

The performance of fM2-PK at W2 to predict response to induction therapy with IFX was superior to that of fLact and fCal, whereas monitoring fLact was the best tool to predict adequately the course of the disease at one year under maintenance IFX in UC.

Biomarkers in Search of Precision Medicine in IBD

The completion of the human genome project in 2003 represented a major scientific landmark, ushering in a new era with hopes and expectations of fresh insights into disease mechanisms and treatments. In inflammatory bowel disease (IBD), many important discoveries soon followed, notably the identification of >200 genetic susceptibility loci and characterization of the gut microbiome. As "big data", driven by advances in technology, becomes increasingly available and affordable, individuals with IBD and clinicians alike yearn for tangible outcomes from the promise of "precision medicine"-precise diagnosis, monitoring, and treatment. Here, we provide a commentary on the prospects and challenges of precision medicine and biomarkers in IBD. We focus on the three key areas where precision IBD will have the most impact: (1) disease susceptibility, activity, and behavior; (2) prediction of drug response and adverse effects; and (3) identification of subphenotypic mechanisms to facilitate drug discovery and selection of new treatments in IBD.

Tissue-infiltrating neutrophils represent the main source of IL-23 in the colon of patients with IBD

OBJECTIVE

In IBD, interleukin-23 (IL-23) and its receptor (IL-23R) are implicated in disease initiation and progression. Novel insight into which cells produce IL-23 at the site of inflammation at an early stage of IBD will promote the development of new tools for diagnosis, treatment and patient monitoring. We examined the cellular source of IL-23 in colon tissue of untreated newly diagnosed paediatric patients with IBD.

DESIGN

Colon tissues from IBD and non-IBD patients were analysed by quantitative real-time PCR (qPCR), immunofluorescence confocal microscopy and flow cytometry after appropriate sample preparation. Blood samples from IBD and non-IBD patients and healthy controls were analysed using flow cytometry and qPCR.

RESULTS

We discovered that tissue-infiltrating neutrophils were the main source of IL-23 in the colon of paediatric patients with IBD, while IL-23(+) human leucocyte antigen-DR(+) or IL-23(+)CD14(+) cells were scarce or non-detectable, respectively. The colonic IL-23(+) neutrophils expressed C-X-C motif (CXC)R1 and CXCR2, receptors for the CXC ligand 8 (CXCL8) chemokine family, and a corresponding CXCR1(+)CXCR2(+)IL-23(+)subpopulation of neutrophils was also identified in the blood of both patients with IBD and healthy individuals. However, CXCL8-family chemokines were only elevated in colon tissue from patients with IBD.

CONCLUSIONS

This study provides the first evidence of CXCR1(+)CXCR2(+)IL-23-producing neutrophils that infiltrate and accumulate in inflamed colon tissue of patients with IBD. Thus, this novel source of IL-23 may play a key role in disease progression and will be important to take into consideration in the development of future strategies to monitor, treat and prevent IBD.

Elevated fecal calprotectin levels during necrotizing enterocolitis are associated with activated neutrophils extruding neutrophil extracellular traps

OBJECTIVE

Neonates with necrotizing enterocolitis (NEC) have higher calprotectin levels in stool than do healthy neonates. However, it is not known whether high stool calprotectin at the onset of bowel symptoms identifies neonates who truly have NEC vs other bowel disorders.

STUDY DESIGN

Neonates were eligible for this study when an x-ray was ordered to 'rule-out NEC'. Stool calprotectin was quantified at that time and in a follow-up stool. Each episode was later categorized as NEC or not NEC. The location of calprotectin in the bowel was determined by immunohistochemistry.

RESULTS

Neonates with NEC had higher initial and follow-up stool calprotectin levels than did neonates without NEC. Calprotectin in bowel from neonates with NEC was within neutrophil extracellular traps (NETs).

CONCLUSION

At the onset of signs concerning for NEC, fecal calprotectin is likely to be higher in neonates with NEC. Calprotectin in their stools is exported from neutrophils via NETs.

Type 1 Diabetes and Dysfunctional Intestinal Homeostasis

Despite the relatively high frequency of gastrointestinal (GI) disorders in individuals with type 1 diabetes (T1D), termed diabetic enteropathy (DE), the pathogenic mechanisms of these disorders remain to be elucidated. While previous studies have assumed that DE is a manifestation of diabetic autonomic neuropathy, other contributing factors such as enteric hormones, inflammation, and microbiota were later recognized. More recently, the emerging role of intestinal stem cells (ISCs) in several GI diseases has led to a new understanding of DE. Given the absence of diagnostic methods and the lack of broadly efficacious therapeutic remedies in DE, targeting factors and pathways that control ISC homeostasis and are dysfunctional in DE may represent a new path for the detection and cure of DE.

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

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

Assessment of cytology and mucin 2 in colorectal mucus collected from patients with inflammatory bowel disease: Results of a pilot trial

BACKGROUND AND AIM

Non-invasive diagnosis of colorectal disease remains problematic, fecal biomarkers presenting the only current option. Colorectal mucus is the diagnostically informative element of stool samples, but its separation from stool is difficult. We aimed to: (i) test a novel method of non-invasive colorectal mucus sampling in a pilot clinical trial; (ii) evaluate sampling method acceptance by study participants; (iii) characterize the collected material cytologically; and (iv) assess feasibility of quantitative protein analysis in the samples.

METHODS

A total of 141 patients with IBD (58), IBS (50), and healthy controls (33) participated in the study. Samples rich in colorectal mucus were self-collected by swabbing the anal area immediately following defecation. Collected samples were examined cytologically and subjected to quantitative analysis for total protein and mucin 2 (MUC2).

RESULTS

The novel sampling technique was assessed as "good" or "adequate" by 96% of study participants. A total of 55% of the collected samples were free of fecal contamination. Cytology showed large numbers of well preserved inflammatory cells in IBD cases. Total protein values varied in all groups, being affected by fecal contamination. MUC2 levels were similar among all IBD-free individuals (control and IBS groups) and elevated in IBD patients (p < 0.001). MUC2 measurement applied as a test for IBD detection provided sensitivity = 72.4% and specificity = 86.7%.

CONCLUSIONS

A novel non-invasive method for collecting human colorectal mucus has been successfully tested. The method was very well accepted by trial participants. The results have proven high quality of collected samples for both cytological investigation and diagnostic biomarker analysis.

A longitudinal study of FDG-PET in Crohn disease patients receiving granulocyte/monocyte apheresis therapy

BACKGROUND AIMS

Endoscopy is the gold standard for the diagnosis and follow-up of patients with Crohn disease (CD). However, a less invasive approach is now being sought for the management of these patients. The objective of this study was to examine whether (18)F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) might be relevant for monitoring the disease activity in CD patients undergoing granulocyte/monocyte apheresis (GMA).

METHODS

This study was conducted in 12 patients with CD who were receiving treatment with 10 once-a-week GMA sessions with the Adacolumn. The response to treatment was monitored by measuring standard laboratory variables, Crohn's Disease Activity Index (CDAI) score, International Organization for the Study of Inflammatory Bowel Diseases (IOIBD) score, and regional and global bowel uptakes on FDG-PET.

RESULTS

In 6 of the 12 patients, significant improvement of the CDAI was observed after the final session of GMA. The patients who showed clinical response to GMA had a decrease in the regional and global bowel uptakes on FDG-PET, whereas those who did not respond showed no change. In the patients who responded to the GMA, the decrease in regional bowel uptake on FDG-PET in each disease area of the same patient varied in parallel. There was a significant correlation between decrease in the global bowel uptake on FDG-PET and improvement of the CDAI and IOIBD scores.

CONCLUSIONS

The longitudinal changes in FDG-PET uptakes are of potential clinical interest for assessing the regional and global bowel disease activity in CD patients undergoing GMA therapy.

Expression and clinical implication of S100A12 in gastric carcinoma

S100 protein family has been implicated in multiple stages of tumorigenesis and progression in which S100A12 is one of the subtypes. However, the role of S100A12 in gastric carcinoma (GC) has not been elucidated yet. This study was aimed to investigate the expression of S100A12 in GC tissues and evaluate the clinical significance of S100A12 in GC patients. S100A12 protein was detected in 207 GC and 52 paired non-cancerous mucosal tissues by immunohistochemistry, while messenger RNA (mRNA) was investigated by Oncomine database analysis. Moreover, survival analysis was performed and the correlation between S100A12 and ubiquitin-specific protease 10 (USP10) and p53 was determined. As for tumor cells, the expression of S100A12 protein and mRNA in GC was proved to be lower than that in non-cancerous mucosa tissues (p < 0.05). Clinicopathological analysis showed that S100A12 protein was negatively associated with tumor size (p = 0.004), depth of invasion (p = 0.022), tumor node metastasis (TNM) stage (p = 0.018), Lauren classification (p < 0.000), and cell differentiation (p < 0.000). In contrast, a positive correlation was found between S100A12 and USP10 protein (p < 0.000). However, no relationship was detected between S100A12 and p53. Moreover, the survival analysis indicated that S100A12 protein was a favorable factor of prognosis of GC (p < 0.05). Although the expression of S100A12 in the stromal cells was detected higher than that in the tumor cells, no relationship between S100A12 protein in stromal cells and the clinicopathological features described above was found (p > 0.05). Our findings suggested that low expression of S100A12 might be served as a new marker in the tumorigenesis and progression of GC.

The diagnostic usefulness of fecal lactoferrin in the assessment of Crohn's disease activity

BACKGROUND

Diagnosis and monitoring of Crohn's disease (CD) is difficult and time-consuming. In recent years, diagnostic usefulness of fecal calprotectin has been proven. However, data on the utility of other fecal markers are scarce.

AIMS

To evaluate the usefulness of fecal lactoferrin (FL) in the assessment of CD activity.

METHODS

The group consisted of 101 CD patients (median age: 30 years, IQR: 24-37). FL was measured in a single stool sample by using the immunoenzymatic methods. The clinical activity of the disease was evaluated by using the Crohn's Disease Activity Index (CDAI). Depending on the location of the disease, either a colonoscopy or magnetic resonance enterography was performed or both in order to evaluate the disease activity by using appropriate endoscopic and enterographic scores.

RESULTS

Median FL concentration was 84.14 (IQR: 36.4-302.9) μg/ml and it correlated with C-reactive protein concentration (p=0.0000001, r=0.5), CDAI (p=0.002, r=0.3) and colonic Simple Endoscopic Score for Crohn's Disease (SES-CD) (p=0.000004, r=0.5). Assuming endoscopic remission in the large intestine with colonic SES-CD≤3 points, a ROC curve showed that FL concentration of 145.82 μg/ml had 84.6% sensitivity and 60.5% specificity in discriminating CD patients with endoscopically active and inactive disease [AUC: 0.676 (95% CI: 0.531-0.8), (p=0.0347)]. The positive predictive value for this concentration was 42% and negative predictive value -92%.

CONCLUSIONS

FL is a sensitive marker of CD activity and it reliably reflects the mucosal inflammatory lesions in large intestine. Thus, it can be helpful in diagnostics and monitoring of CD.

Assessment of mucosal healing in inflammatory bowel disease: review

BACKGROUND AND AIMS

Mucosal healing is an important treatment end-point in inflammatory bowel disease, and achieving mucosal healing has been demonstrated to improve disease-related outcomes. Considerable uncertainty exists, however, regarding the optimal approach for the assessment of mucosal healing.

AIMS

To compare currently available diagnostic tools for the assessment of mucosal healing and outline the ideal approach to integrating these tools into clinical trials and clinical practice.

METHODS

Review article.

RESULTS

Endoscopy represents the criterion standard for the assessment of mucosal healing, and frequent endoscopic assessment is associated with a higher rate of achieving mucosal healing. The use of mucosal biopsy allows for the identification of persistent histologic disease activity, but the incremental clinical benefit of achieving histologic healing is yet to be determined. Magnetic resonance enterography has a high sensitivity for ulcer healing in endoscopically inaccessible disease activity. However, the presence of mucosal lesions cannot be reliably excluded based on this modality alone, and further small-bowel endoscopy should be considered in symptomatic patients. Video capsule endoscopy or device-assisted enteroscopy can be used, with device-assisted enteroscopy being preferred in stricturing Crohn's disease because of the risk of capsule retention or in patients in whom small-bowel malignancy is a possibility.

CONCLUSIONS

Endoscopy remains the criterion standard for the assessment of mucosal healing. Several alternative diagnostic modalities have become available that can be of value in specific clinical circumstances, particularly in patients with small-bowel involvement.

Knowledge of Fecal Calprotectin and Infliximab Trough Levels Alters Clinical Decision-making for IBD Outpatients on Maintenance Infliximab Therapy

BACKGROUND

Infliximab is an effective therapy for inflammatory bowel disease (IBD). However, more than 50% of patients lose response. Empiric dose intensification is not effective for all patients because not all patients have objective disease activity or subtherapeutic drug level. The aim was to determine how an objective marker of disease activity or therapeutic drug monitoring affects clinical decisions regarding maintenance infliximab therapy in outpatients with IBD.

METHODS

Consecutive patients with IBD on maintenance infliximab therapy were invited to participate by providing preinfusion stool and blood samples. Fecal calprotectin (FCP) and infliximab trough levels (ITLs) were measured by enzyme linked immunosorbent assay. Three decisions were compared: (1) actual clinical decision, (2) algorithmic FCP or ITL decisions, and (3) expert panel decision based on (a) clinical data, (b) clinical data plus FCP, and (c) clinical data plus FCP plus ITL. In secondary analysis, Receiver-operating curves were used to assess the ability of FCP and ITL in predicting clinical disease activity or remission.

RESULTS

A total of 36 sets of blood and stool were available for analysis; median FCP 191.5 μg/g, median ITLs 7.3 μg/mL. The actual clinical decision differed from the hypothetical decision in 47.2% (FCP algorithm); 69.4% (ITL algorithm); 25.0% (expert panel clinical decision); 44.4% (expert panel clinical plus FCP); 58.3% (expert panel clinical plus FCP plus ITL) cases. FCP predicted clinical relapse (area under the curve [AUC] = 0.417; 95% confidence interval [CI], 0.197-0.641) and subtherapeutic ITL (AUC = 0.774; 95% CI, 0.536-1.000). ITL predicted clinical remission (AUC = 0.498; 95% CI, 0.254-0.742) and objective remission (AUC = 0.773; 95% CI, 0.622-0.924).

CONCLUSIONS

Using FCP and ITLs in addition to clinical data results in an increased number of decisions to optimize management in outpatients with IBD on stable maintenance infliximab therapy.

Clinical utility of fecal neutrophil-derived biomarkers in evaluating activity of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a group of chronic, idiopathic intestinal diseases characterized by periods of remission and relapses. Evaluating the activity of IBD timely and accurately is crucial to guide treatment. The change of neutrophils in the intestinal tissue is correlated closely with the activity of IBD. This article reviews the clinical utility of fecal neutrophil-derived biomarkers in assessing the activity of IBD.