Fecal Calprotectin in Assessing Endoscopic and Histological Remission in Patients with Ulcerative Colitis

To STRIDE or not to STRIDE: a critique of "treat to target" in ulcerative colitis

INTRODUCTION

The STRIDE consensus intends to complement the clinical endpoint with an endoscopic endpoint of mucosal healing and others as treatment targets in ulcerative colitis. If these targets are not reached, STRIDE requires dose or timing adjustments or switching the medication. This narrative review provides a critique of this concept.

AREAS COVERED

We analyze and discuss the limitations of current endpoints as targets, their currently limited achievability, and the lacking evidence from controlled trials relating to 'treat to target.' The relevant publications in PubMed were identified in a literature review with the key word 'ulcerative colitis.'

EXPERT OPINION

In ulcerative colitis, the standard clinical target is measured traditionally by the MAYO-score, but in variable combinations of patient and physician reported outcomes as well as also different definitions of the endoscopic part. Only a score of 0 is more stringent than clinical remission but is only achieved by a minority of patients in first and even less in second line therapy. The concept is not based on clear evidence that patients indeed benefit from appropriate escalation of treatment. Until the STRIDE approach is proven to be superior to standard treatment focusing on clinical well-being, the field should remain reluctant.

Factors Associated With Response to Rescue Therapy in Acute Severe Ulcerative Colitis

BACKGROUND

Acute severe ulcerative colitis (ASUC) is a medical emergency for which colectomy is required in patients who do not respond to rescue therapy. While previous studies have predominantly focused on predicting outcome to first-line corticosteroid therapy, there is a need to understand the factors associated with response to rescue therapies in order to improve clinical outcomes. We reviewed the evidence regarding factors associated with response to rescue therapy in adults with ASUC and identified future directions for research.

METHODS

A systematic search of the literature was conducted, and 2 reviewers independently assessed studies for inclusion.

RESULTS

Of 3509 records screened, 101 completed studies were eligible for inclusion. We identified 42 clinical, hematological, biochemical, endoscopic, or pharmacological factors associated with response to rescue therapy. Older age (≥50 years), thiopurine experience, and cytomegalovirus or Clostridioides difficile infection were associated with a higher risk of nonresponse to rescue therapy. Biochemical factors associated with poorer response included an elevated C-reactive protein (CRP) ≥30mg/L on admission, hypoalbuminemia and an elevated ratio of CRP to albumin. Severe endoscopic findings, including a Mayo endoscopic score of 3 or Ulcerative Colitis Endoscopic Index of Severity ≥5, portended poorer outcomes. The role of fecal calprotectin and therapeutic value of measuring infliximab drug levels in ASUC remain to be defined.

CONCLUSIONS

Response to rescue therapy can be predicted by several specific factors, which would aid clinical decision-making. Existing and emerging factors should be integrated within predictive and prognostic models to help improve clinical outcomes.

Optimizing maternal and neonatal outcomes through tight control management of inflammatory bowel disease during pregnancy: a pilot feasibility study

A home point-of care FCP test (IBDoc) and a self-reported clinical disease activity program (IBD Dashboard) may improve routine monitoring of IBD activity during pregnancy. We aimed to evaluate the feasibility of tight control management using remote monitoring in pregnant patients with IBD. Pregnant patients (< 20 weeks) with IBD were prospectively enrolled from Mount Sinai Hospital between 2019 and 2020. Patients completed the IBDoc and IBD Dashboard at three core time points. Disease activity was measured clinically using the Harvey-Bradshaw Index (mHBI) for CD and partial Mayo (pMayo) for UC, or objectively using FCP. A feasibility questionnaire was completed in the third trimester. Seventy-seven percent of patients (24 of 31) completed the IBDoc and IBD Dashboard at all core time points. Twenty-four patients completed the feasibility questionnaires. All survey respondents strongly preferred using the IBDoc over standard lab-based testing and would use the home kit in the future. Exploratory analysis identified discordance rates of more than 50% between clinical and objective disease activity. Tight control management using remote monitoring may be feasible among pregnant patients with IBD. A combination of both clinical scores and objective disease markers may better predict disease activity.

The treatment principles and targets for intestinal Behcet's disease

Behcet's disease (BD) is a chronic and recurrent systemic vasculitis involving large, medium and small blood vessels as well as arteries and veins. BD with predominant gastrointestinal manifestations is diagnosed as intestinal BD, which is associated with severe complications such as massive gastrointestinal hemorrhage, perforation, and obstruction. Recently, treat-to-target (T2T) strategies have been successfully used in many chronic diseases and been suggested in the management of BD, while there are no related reviews about the global treatment strategy including treatment principles and targets for intestinal BD in detail. Herein, we review the treatment principles from the aspects of departments of Rheumatology and Gastroenterology. In addition, treatment targets of intestinal BD are reviewed from three aspects such as evaluable markers, effective markers and potency-ratio markers. Some definitions and conceptions from inflammatory bowel disease (IBD) bring us reference and enlightenments.

The value of fecal calprotectin in Clostridioides difficile infection: A systematic review

As a marker of inflammation, calprotectin has potential application value in a variety of inflammatory diseases, such as arthritis and bacterial infections. Clostridioides difficile infection (CDI) is an infectious disease that causes intestinal damage and inflammation. This systematic review aims to determine whether fecal calprotectin has application value in CDI. Nine databases were searched from inception to 6 June 2022, and 17 studies were included. These studies were divided into four groups according to their content. Generally speaking, fecal calprotectin is not an ideal indicator for the diagnosis and prognosis prediction of CDI but may serve as a potential indicator for assessing disease severity and as a readily detectable marker for CDI screening. In addition, patients in need of treatment or with detectable toxins in stool may tend to have higher levels of fecal calprotectin. In summary, fecal calprotectin has some potential application value in CDI. However, further studies are needed to verify these findings and determine the reliability of calprotectin as a biomarker for CDI.

Disease Monitoring in Inflammatory Bowel Disease: Evolving Principles and Possibilities

Inflammatory bowel disease is a progressive and debilitating condition. Early and effective treatment using a treat-to-target approach is key to improving patient outcomes. Therefore, proactive monitoring is essential to ensure that treatment strategies are working and targets are being met. In this review we discuss the current monitoring tools available to us and how they can be used. We also discuss the importance of monitoring during key phases of the disease and propose an optimum treat-to-target monitoring strategy for Crohn's disease and ulcerative colitis. Regarding the advent of new technology, we discuss how this may improve our monitoring capabilities and how we envisage future monitoring strategies of inflammatory bowel diseases.

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

INTRODUCTION

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

RESULTS

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

DISCUSSION

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

Noninvasive biomarkers identify eosinophilic esophagitis: A prospective longitudinal study in children

BACKGROUND

Esophageal histology is critical for diagnosis and surveillance of disease activity in eosinophilic esophagitis (EoE). A validated noninvasive biomarker has not been identified. We aimed to determine the utility of blood and urine eosinophil-associated proteins to diagnose EoE and predict esophageal eosinophilia.

METHODS

Blood and urine were collected from children undergoing endoscopy with biopsy. Absolute eosinophil count (AEC), plasma eosinophil-derived neurotoxin (EDN), eosinophil cationic protein (ECP), major basic protein-1 (MBP-1), galectin-10 (CLC/GAL-10), Eotaxin-2 and Eotaxin-3, and urine osteopontin (OPN) and matrix metalloproteinase-9 (MMP-9) were determined. Differences were assessed between EoE and control, and with treatment response. The capacity to predict EoE diagnosis and esophageal eosinophil counts was assessed.

RESULTS

Of 183 specimens were collected from 56 EoE patients and 15 non-EoE controls with symptoms of esophageal dysfunction; 33 EoE patients had paired pre- and post-treatment specimens. Plasma (CLC/GAL-10, ECP, EDN, Eotaxin-3, MBP-1) and urine (OPN) biomarkers were increased in EoE compared to control. A panel comprising CLC/GAL-10, Eotaxin-3, ECP, EDN, MBP-1, and AEC was superior to AEC alone in distinguishing EoE from control. AEC, CLC/GAL-10, ECP, and MBP-1 were significantly decreased in patients with esophageal eosinophil counts <15/hpf in response to treatment. AEC, CLC/GAL-10, ECP, EDN, OPN, and MBP-1 each predicted esophageal eosinophil counts utilizing mixed models controlled for age, gender, treatment, and atopy; AEC combined with MBP-1 best predicted the counts.

CONCLUSIONS

We identified novel panels of eosinophil-associated proteins that along with AEC are superior to AEC alone in distinguishing EoE from controls and predicting esophageal eosinophil counts.

Optimal Range of Fecal Calprotectin for Predicting Mucosal Healing in Patients with Inflammatory Bowel Disease: A Systematic Review and Meta-Analysis

Objective

Fecal calprotectin (FC) is a promising marker for assessment of inflammatory bowel disease (IBD) activity. However, the utility of FC for predicting mucosal healing (MH) of IBD patients has yet to be clearly demonstrated. The objective of our study was to perform a meta-analysis evaluating the diagnostic accuracy of FC in predicting MH of IBD patients.

Methods

We systematically searched the databases for studies from inception to April 2020 that evaluated MH in IBD. The methodological quality of each study was assessed according to the Quality Assessment of Diagnostic Accuracy Studies checklist. The extracted data were pooled using a summary receiver operating characteristic curve model. Random-effects model was used to summarize the diagnostic odds ratio, sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio.

Results

Sixteen studies comprising 1,682 ulcerative colitis (UC) patients and 4 studies comprising 221 Crohn's disease (CD) patients were included. The best performance of FC for predicting MH in UC was at cut-off range of 60-75 μg/g with area under the curve (AUC) of 0.88 and pooled sensitivity and specificity of 0.87 and 0.79, respectively. The pooled sensitivity and specificity values of cutoff range 180-250 μg/g for predicting MH in CD were 0.67 and 0.76, respectively. The AUC of 0.79 also revealed improved discrimination for identifying MH in CD with FC concentration.

Conclusion

Our meta-analysis has found that FC is a simple, reliable noninvasive marker for predicting MH in IBD patients. FC cutoff range 60-75 μg/g appears to have the best overall accuracy in UC patients.

Association of Fecal Calprotectin With Endoscopic and Histologic Activity in Pediatric Inflammatory Bowel Disease

Fecal calprotectin (FC) is a noninvasive marker of intestinal inflammation used for screening and ongoing monitoring of inflammatory bowel disease (IBD); it is unclear the association of specific FC values with disease activity. The aim of our study was to examine the association of FC values with endoscopic and histologic severity.

Methods

We performed a retrospective chart review of patients who had FC done between 30 days and 1 day before colonoscopy at our institution. IBD patients were graded using the simple endoscopic score for Crohn's disease or Mayo endoscopic score for ulcerative colitis. Histologic slides were graded using the Geboes method.

Results

Three-hundred thirty-one patients were included in the study and 107 had IBD. For endoscopy, median FC was lowest for all IBD patients with no disease (181 μg/g) and highest in severe disease (921 μg/g), with significant difference between no disease and moderate and severe disease (P = 0.019, 0.003), and between mild and severe disease (P = 0.012). For histology, median FC was lowest with no disease (328 μg/g) and highest in severe disease (895 μg/g), with significant difference between no disease and moderate and severe disease (P = 0.021, 0.018). The control population had a significantly lower median FC than the IBD population in endoscopic remission (35.5 versus 181 μg/g; P = 0.018).

Conclusions

There was a linear increase in FC values associated with increasing disease severity in the undifferentiated IBD cohort. Values for IBD patients in endoscopic remission were significantly different from our control population. FC may be a useful noninvasive marker to assess disease severity.

Experimental infectious challenge in pigs leads to elevated fecal calprotectin levels following colitis, but not enteritis

BACKGROUND

Fecal calprotectin is largely applied as a non-invasive intestinal inflammation biomarker in human medicine. Previous studies in pigs investigated the levels of fecal calprotectin in healthy animals only. Thus, there is a knowledge gap regarding its application during infectious diarrhea. This study investigated the usefulness of fecal calprotectin as a biomarker of intestinal inflammation in Brachyspira hyodysenteriae and Salmonella Typhimurium infected pigs.

RESULTS

Fecal samples from pigs with colitis (n = 18) were collected from animals experimentally inoculated with B. hyodysenteriae (n = 8) or from sham-inoculated controls (n = 3). Fecal samples from pigs with enteritis (n = 14) were collected from animals inoculated with Salmonella enterica serovar Typhimurium (n = 8) or from sham-inoculated controls (n = 4). For both groups, fecal samples were scored as: 0 = normal; 1 = soft, wet cement; 2 = watery feces; 3 = mucoid diarrhea; and 4 = bloody diarrhea. Fecal calprotectin levels were assayed using a sandwich ELISA, a turbidimetric immunoassay and a point-of-care dipstick test. Fecal calprotectin levels were greater in colitis samples scoring 4 versus ≤ 4 using ELISA, and in feces scoring 3 and 4 versus ≤ 1 using immunoturbidimetry (P < 0.05). No differences were found in calprotectin concentration among fecal scores for enteritis samples, regardless of the assay used. All samples were found below detection limits using the dipstick method.

CONCLUSIONS

Fecal calprotectin levels are increased following the development of colitis, but do not significantly change due to enteritis. While practical, the use of commercially available human kits present sensitivity limitations. Further studies are needed to validate the field application of calprotectin as a marker of intestinal inflammation.

Peptidomic and proteomic analysis of stool for diagnosing IBD and deciphering disease pathogenesis

Background The sensitivities and specificities of C-reactive protein (CRP) and faecal calprotectin (fCal), as recommended for inflammatory bowel diseases (IBD) diagnosis and monitoring, are low. Our aim was to discover new stool protein/peptide biomarkers for diagnosing IBD. Methods For peptides, MALDI-TOF/MS (m/z 1000-4000) was performed using stools from an exploratory (34 controls; 72 Crohn's disease [CD], 56 ulcerative colitis [UC]) and a validation (28 controls, 27 CD, 15 UC) cohort. For proteins, LTQ-Orbitrap XL MS analysis (6 controls, 5 CD, 5 UC) was performed. Results MALDI-TOF/MS spectra of IBD patients had numerous features, unlike controls. Overall, 426 features (67 control-associated, 359 IBD-associated) were identified. Spectra were classified as control or IBD (absence or presence of IBD-associated features). In the exploratory cohort, the sensitivity and specificity of this classification algorithm were 81% and 97%, respectively. Blind analysis of the validation cohort confirmed 97% specificity, with a lower sensitivity (55%) paralleling active disease frequency. Following binary logistic regression analysis, IBD was independently correlated with MALDI-TOF/MS spectra (p < 0.0001), outperforming fCal measurements (p = 0.029). The IBD-correlated m/z 1810.8 feature was a fragment of APC2, homologous with APC, over-expressed by infiltrating cells lining the surface in UC or the muscularis-mucosae in CD (assessed by immunohistochemistry). IBD-associated over-expressed proteins included immunoglobulins and neutrophil proteins, while those under-expressed comprised proteins of the nucleic acid assembly or those (OLFM4, ENPP7) related to cancer risk. Conclusions Our study provides evidence for the clinical utility of a novel proteomic method for diagnosing IBD and insight on the pathogenic role of APC. Moreover, the newly described IBD-associated proteins might become tools for cancer risk assessment in IBD patients.

A comparison of diagnostic performance between two quantitative rapid fecal calprotectin assays in detecting active inflammatory bowel disease

Background

Fecal calprotectin (FC) is widely used for the diagnosis and monitoring disease activity of inflammatory bowel disease (IBD). Quantitative rapid assays can be a reliable alternative to the time-consuming assay. This study aimed to evaluate and compare the diagnostic performance of two quantitative rapid FC assays (Ichroma calprotectin, and Buhlmann Quantum blue).

Methods

A total of 192 patients were included in this study; 84 patients with IBD (67 ulcerative colitis and 17 Crohn’s disease) and 108 patients with non-IBD. We compared quantitative FC levels in different disease statuses and evaluated the correlation between the FC results of the two FC kits. Diagnostic performances in predicting active IBD were evaluated in reference to different cut-off levels.

Results

The FC levels in 45 patients with active IBD as defined by endoscopic score were significantly higher compared to the inactive IBD and other diseases (P<0.05). Although the two assays’ results correlated (r = 0.642, P < 0.001), a significant deviation was observed (y (Buhlmannn) = -45.2 +8.9X (Ichroma)). The Diagnostic performances in predicting active IBD were comparable as area under the curve (AUC), 0.812, cut-off, 50, sensitivity, 64.4%, and specificity, 85.0% for iChroma assay and AUC, 0.826, cut-off, 100, sensitivity, 84.4%, and specificity 61.9% for Buhlmann Quantum Blue assay. FC levels using a cut-off of > 250 μg/g confirmed 85.7% (iChroma) and 64.1% (Buhlmann) of active IBD patients.

Conclusion

The results of the two rapid FC assays iChroma and Buhlmann showed a significant correlation, but the two test results were not interchangeable. With optimized cut-off values, rapid FC tests could be helpful in the diagnosis of IBD and differentiating active IBD from inactive or organic bowel disease.

Prostaglandin E-Major Urinary Metabolite Predicts Relapse in Patients With Ulcerative Colitis in Clinical Remission

INTRODUCTION:

Prostaglandin E-major urinary metabolite (PGE-MUM) is a novel biomarker reflecting endoscopic activity in ulcerative colitis (UC). However, there are no studies investigating the efficacy of PGE-MUM as a biomarker for predicting relapse. We investigated whether PGE-MUM can predict clinical relapse of UC.

METHODS:

The measurement of PGE-MUM and endoscopic evaluation were performed in 70 patients with UC in clinical remission. The optimal cutoff values predicting relapse and relapse-free rate were analyzed.

RESULTS:

Sixteen patients (22.9%) relapsed during the 12-month follow-up. The median PGE-MUM value of relapsed patients at entry was significantly higher than that of patients in clinical remission (P = 0.008). The cutoff value of PGE-MUM predicting future relapse was 25.2 μg/g Cr by receiver-operating characteristic (ROC) analysis, and the area under the ROC curve was 0.721 (95% confidence interval: 0.556–0.886). The relapse-free rate of patients with PGE-MUM ≥25.2 μg/g Cr was significantly lower than that in patients with PGE-MUM <25.2 μg/g Cr (log-rank test: P < 0.001). The ROC analysis of UC patients with disease duration more than 1–8 years showed that duration of more than 5 years had the largest area under the ROC curve 0.821 (95% confidence interval: 0.583–1.000) and that the optimal cutoff value was 26.3 μg/g Cr.

DISCUSSION:

PGE-MUM is a reliable biomarker for predicting future relapse, particularly in UC patients with long-disease duration.

C-reactive protein is superior to fecal biomarkers for evaluating colon-wide active inflammation in ulcerative colitis

We evaluated the association between endoscopic scores of colonic inflammation and fecal calprotectin (FC), fecal immunochemical occult blood test (FIT), and C-reactive protein (CRP) in patients with ulcerative colitis (UC). Endoscopic scores reflecting the most severe lesion [maximum Mayo Endoscopic Subscore (M-MES) and Ulcerative Colitis Endoscopic Index of Severity (UCEIS)] and those reflecting the inflammation of the entire colon [sum of MES (S-MES) and Ulcerative Colitis Colonoscopic Index of Severity (UCCIS)] were evaluated. FC, FIT, and CRP were measured, and their association with the four endoscopic scores was evaluated. Endoscopic scores of 78 complete colonoscopies (66 UC patients) were evaluated using the three biomarkers. FC and CRP tended to correlate more strongly with S-MES and UCCIS than with M-MES and UCEIS. In the M-MES 0, 1 group, compared to CRP, FC and FIT showed stronger correlations with S-MES and UCCIS. Conversely, in the M-MES 2, 3 group, only CRP was significantly correlated with each descriptor. CRP more strongly reflects colon-wide mucosal inflammation than FC and allows reliable assessment of inflammation throughout the colon in active UC.

Faecal Calprotectin in Assessment of Mucosal Healing in Adults with Inflammatory Bowel Disease: A Meta-Analysis

Achieving mucosal healing in patients with inflammatory bowel disease is related to a higher incidence of sustained clinical remission and it translates to lower rates of hospitalisation and surgery. The assessment methods of disease activity and response to therapy are limited and mainly rely on colonoscopy. This meta-analysis reviews the effectiveness of using faecal calprotectin as a marker for mucosal healing in inflammatory bowel disease. Two meta-analyses were conducted in parallel. The analysis on the use of faecal calprotectin in monitoring mucosal healing in colonic Crohn’s disease is based on 16 publications (17 studies). The data set for diagnostic values of faecal calprotectin in ulcerative colitis is composed of 35 original publications (total 49 studies). The DOR for the use of faecal calprotectin in Crohn’s disease is estimated to be 11.20 and the area under the sROCis 0.829. In cases of ulcerative colitis, the DOR is 14.48, while the AUC sROC is 0.858. Heterogeneity of the studies was moderatetosubstantial. Collected data show overall good sensitivity and specificity of the faecal calprotectin test, as well as a good DOR. Thus, monitoring of mucosal healing with a non-invasive faecal calprotectin test may represent an attractive option for physicians and patients with inflammatory bowel disease.

Clinical, Endoscopic and Histological Outcomes in Induction of Moderate-to-Severe Ulcerative Colitis: A Systematic Review with Meta-Analysis

BACKGROUND AND AIMS

Interest in histology for ulcerative colitis [UC] has increased recently. This systematic review and meta-analysis aims to assess, for the first time, whether histological outcomes are more informative than endoscopic and clinical outcomes in distinguishing the impact of intervention over placebo in induction trials.

METHODS

MEDLINE, ScienceDirect and Cochrane Central Register of Controlled Trials were searched to identify randomized placebo-controlled trials [RCTs] enrolling moderate-to-severe UC patients. Studies were assessed using the Quality Assessment Tool for Studies with Diverse Designs. We analysed the pooled proportion of patients achieving clinical, endoscopic and histological remission and response after a pharmacological intervention and compared the results with those of placebo-treated patients by using a random-effects model.

RESULTS

From 889 identified records, 13 RCTs were included. The odds ratio [OR] for remission was higher in patients receiving intervention than in those under placebo for clinical (OR 2.13, 95% confidence interval [CI] 1.33-3.43), endoscopic [OR 1.46, 95% CI 0.19-11.18] and histological remission [OR 1.85, 95% CI 1.20-2.84]. Significant differences were observed for all response outcomes [clinical: OR 2.27, 95% CI 1.84-2.85; endoscopic: OR 2.16, 95% CI 1.51-3.10; histological: OR 3.63, 95% CI, 1.41-9.36]. No significant heterogeneity existed; no subgroup effects were found for duration of the induction or histological scale [p > 0.05]. Clinical and histological remission and endoscopic response were concordant in discriminating interventions from placebo.

CONCLUSION

Histological outcomes are informative in trials of moderate-to-severe UC. Further studies analysing histology at the end of induction are needed to confirm its relevance in distinguishing the efficacy of an intervention over placebo in comparison to clinical and endoscopic outcomes and to explore its prognostic value.

Can fecal calprotectin accurately identify histological activity of ulcerative colitis? A meta-analysis

BACKGROUND AND AIMS

Elevated fecal calprotectin (FC) levels have been reported to correlate with histological activity in patients with ulcerative colitis (UC). However, the accuracy of FC for evaluating histological activity of UC remains to be determined. The aim of this study was to determine the accuracy of FC for evaluating histological activity of UC, based on updated definitions.

METHODS

Related studies were retrieved from the PubMed, Web of Science, Embase, and Cochrane databases. Adult participants diagnosed with UC were included when sufficient data could be extracted to calculate the accuracy of FC for evaluating histological activity. The primary outcome was histological response, and the secondary outcome was histological remission, defined according to a recently updated position paper of European Crohn's and Colitis Organization. Statistics were pooled using bivariate mixed-effects models. The area under the curve was estimated by summary receiver-operating characteristic curves.

RESULTS

Nine studies were included, from which 1039 patients were included for the analysis of histological response and 591 patients for histological remission. For the evaluation of histological response, the pooled sensitivity, specificity, and the area under the curve were 0.69 [95% confidence interval (CI): 0.52-0.82], 0.77 (95% CI: 0.63-0.87), and 0.80 (95% CI: 0.76-0.83), respectively. For the evaluation of histological remission, the corresponding estimates were 0.76 (95% CI: 0.71-0.81), 0.71 (95% CI: 0.62-0.78), and 0.79 (95% CI: 0.75-0.82), respectively. FC had a higher accuracy in studies using Nancy Index. For histological response, the cut-off values of FC ranged from 50 to 172 µg/g, and the sensitivity was higher in studies with FC cut-off values >100 µg/g (0.77 versus 0.65).

CONCLUSION

FC is a valuable biomarker for assessing histological activity in patients with UC. A cut-off value of 100-200 µg/g is more appropriate to spare patients from an unnecessary endoscopy and biopsy.

Fecal Calprotectin Is Elevated in HIV and Related to Systemic Inflammation

BACKGROUND

Fecal calprotectin (FC), a biomarker of gastrointestinal (GI) inflammation, is used in the diagnosis and management of inflammatory bowel disease. HIV infection severely damages gut-associated lymphoid and epithelial tissues leading to GI inflammation that drives systemic inflammation and increases subsequent risk of comorbidities. For the first time, we compared FC concentrations by HIV and antiretroviral therapy (ART) status and determined the relationship to systemic inflammation.

METHODS

People with and without HIV were enrolled and underwent a comprehensive clinical and laboratory assessment. Stool samples were collected, and FC was measured by enzyme-linked immunosorbent assay ELISA. Plasma biomarkers of inflammation were also measured.

RESULTS

One hundred one participants with HIV (83 ART-treated and 18 ART-naive) and 89 uninfected controls were enrolled. There were no significant differences between ART-naive and ART-treated participants, but both HIV groups had significantly higher FC concentrations than controls when FC was considered as a continuous variable or by cut-offs used in inflammatory bowel disease. The highest median and largest proportion of participants with FC >100 µg/g were seen in ART-naive, followed by ART-treated and then controls. Among HIV participants, FC concentrations were positively associated with high-sensitivity C-reactive protein, soluble tumor necrosis factor receptor II, and soluble vascular cellular adhesion molecule and inversely associated with CD4 counts.

CONCLUSIONS

FC concentrations are elevated in HIV regardless of ART status. ART and immune reconstitution seem to reduce FC but not to concentrations seen in uninfected controls. Our results suggest a role for FC as a noninvasive surrogate measurement of GI inflammation and associated systemic inflammation in HIV.

Fecal calprotectin concentration to assess endoscopic and histologic remission in patients with cancer with immune-mediated diarrhea and colitis

Background

Immune-mediated diarrhea and colitis (IMDC) is currently diagnosed and monitored by evaluating clinical symptoms. Deep remission is determined by endoscopic and histologic evaluation of the disease process. However, repeating these invasive procedures frequently can become cumbersome. We sought to assess the role of fecal calprotectin (FC) concentration as a non-invasive biomarker of endoscopic or histologic remission.

Methods

We performed a retrospective study of patients with IMDC who were tested for FC at IMDC onset and after IMDC treatment between June 2016 and March 2020. Patient demographics, clinical variables, and FC data were collected and analyzed to determine the optimal cut-off FC concentration to predict endoscopic and histologic remission.

Results

Our sample comprised 77 patients with a median age of 62 years; 66% were male and 94% were Caucasian. Sixty-five patients (84%) achieved clinical remission, 46 (60%) achieved endoscopic remission, and 24 (31%) achieved histologic remission after IMDC treatment. FC concentrations decreased from the time of IMDC onset to the end of treatment (p<0.001). High FC concentrations were associated with evident endoscopic inflammation (p=0.003) and acute/chronic active colitis (p=0.025) which positively correlated with the Mayo Endoscopic Subscore (r=0.615, p=0.001) at the time of IMDC onset. In patients who achieved endoscopic remission after treatment, a significantly lower FC concentration was observed at IMDC onset (p=0.006) and after treatment (p<0.001) compared with those without endoscopic remission. The cut-off FC concentration to predict endoscopic remission was ≤116 μg/g and for histologic remission ≤80 μg/g; these cut-offs had optimal specificity (94% and 85%, respectively) and positive predictive value (0.91 and 0.38, respectively).

Conclusions

FC concentration may serve as a non-invasive biomarker to predict endoscopic and histologic remission in patients receiving treatment for IMDC, minimizing the need for frequent invasive endoscopies. Future prospective studies are needed to provide further insight on the role of this marker in disease surveillance.

Correlation of Biomarkers with Endoscopic Score: Ulcerative Colitis Endoscopic Index of Severity (UCEIS) in Patients with Ulcerative Colitis in Remission

Background and Objectives: Ulcerative colitis is a disease with an unpredictable evolution, often highlighted endoscopically, that is associated with persistent inflammation affecting the patient’s quality of life. An attempt was made to discover surrogate markers to evaluate the endoscopic remission of the disease in order to increase the patient’s quality of life and also their adherence to the treatment and monitoring plan. One such marker is fecal calprotectin (FC). To confirm the correlation between biomarkers and endoscopic disease activity and to define the optimal cut off value to detect clinical and endoscopic remission in a center of Romania. Materials and Methods: This was a prospective study that included 59 patients diagnosed with ulcerative colitis at the Department of Internal Medicine III, University Emergency Hospital of Bucharest. Patients had fecal calprotectin measurements and colonoscopy/rectosigmoidoscopy performed during baseline, 6 and 12 months. For endoscopic activity the Ulcerative Colitis Endoscopic Index of Severity (UCEIS) was used. Results: During the study, relapses have occurred in 35.6% of patients, the median age was 47 years (21–77). During the study, the FC measurement was significantly increased at 3 months (median, range µg/g; 715, 14–4000) and at 6 months (median, range µg/g; 650, 4.5–3000) (p ≤ 0.05). Another inflammatory biomarker studied was CRP, which showed increased values at 3 months (median, range, mg/dL; 1.86, 0.14–58.9), at 6 months (median, range, mg/dL; 2.36, 0.12–45.8) and at 9 months (median, range, mg/dL; 2, 0.12–25.9) compared to the baseline (p = 0.01). Patients with recurrence of the disease also associated an increase in the values of clinical evaluation scores (SCCAI; p = 0.00001), but also endoscopic (UCEIS; p = 0.0006) Conclusion: A relapse is associated independently with younger age, the extension of the disease (E2-E3), increased FC level, C reactive protein, hemoglobin concentration, SCCAI index and UCEIS score.

ECCO Position Paper: Harmonization of the Approach to Ulcerative Colitis Histopathology

Currently, the main targets of drug therapy for ulcerative colitis [UC] are endoscopic and clinical remission. However, there is active discussion about the additional advantages of including histological remission as a target. Accumulating evidence indicates that microscopic activity persists in endoscopically quiescent UC, that histological changes may lag behind clinical remission after treatment, and that absence of histological activity predicts lower rates of relapse, hospitalization, surgery and subsequent neoplasia. Obtaining useful information from mucosal biopsies in this setting depends on accurate and consistent evaluation of histological features. However, there is no standardization of biopsy procedures, histological sample processing technique or histological scoring systems, and there is no agreement on the definitions of histological remission, response or activity. Accordingly, a consensus expert panel convened by the European Crohn's and Colitis Organisation [ECCO] reviewed the literature and agreed a number of position statements regarding harmonization of UC histopathology. The objective was to provide evidence-based guidance for the standardization and harmonization of procedures, definitions and scoring systems for histology in UC, and to reach expert consensus where possible. We propose the absence of intraepithelial neutrophils, erosion and ulceration as a minimum requirement for the definition of histological remission. For randomized control trials we recommend the use of the Robarts histopathology index [RHI] or the Nancy index [NI]. For observational studies or in clinical practice we recommend the use of the NI. To predict the risk of future neoplasia in UC, cumulative histological scores over time are more useful than single scores.

Calprotectin in inflammatory bowel disease

The term IBD is usually used for referring to a group of inflammatory gastro-intestinal diseases (mainly Crohn's disease and ulcerative colitis). Accordingly, IBD arises as a result of inappropriate immune response to intestinal commensal organisms among genetically susceptible individuals. Performing colonoscopy and histopathologic evaluation on an inflamed bowel biopsy specimen are currently considered as gold standards for diagnosis and management of IBD. Correspondingly, these techniques are known to be invasive and costly. In recent decades, fecal calprotectin, as a biomarker, has received much attention for the diagnosis and non-invasive management of IBD. Up to now, many studies have investigated the efficacy of fecal calprotectin in the areas of IBD differentiation from IBS, prediction of endoscopic and histologic activities of IBD and prediction of disease recurrence. Although some of these studies have reported promising results, some others have shown significant limitations. Therefore, in this paper, we reviewed the most interesting ones of these studies after a brief discussion of the laboratory measurement of fecal calprotectin. Moreover, we attempted to provide an answer for the question of whether fecal-calprotectin could be considered as a potential surrogate marker for colonoscopy.

Treat-to-target approach in the management of inflammatory Bowel disease

With the advent of biologic and small molecule therapies, there has been a substantial change in the treatment of inflammatory bowel disease. These advances have had a great impact in preventing disease progression, intestinal damage and, therefore, have contributed to a better quality of life. Discordance between symptom control and mucosal healing has been demonstrated. This has led to the search for new disease control targets. The treat to target strategy, based on expert recommendations and now a randomized controlled trial, has determined that clinical and endoscopic remission should be the goal of therapy. Biomarkers (fecal calprotectin) can be a surrogate target. Although histological healing has shown benefits, there is inadequate evidence and inadequate therapy for that to be a fixed goal at this time. This review will focus on therapeutic goals, according to the evidence currently available, and evaluate strategies to achieve them.

Biochemical Biomarkers of Mucosal Healing for Inflammatory Bowel Disease in Adults

Mucosal healing (MH) is the key therapeutic target of inflammatory bowel disease (IBD). The evaluation of MH remains challenging, with endoscopy being the golden standard. We performed a comprehensive overview of the performance of fecal-, serum-, and urine-based biochemical markers in colonic IBD to find out whether we are ready to replace endoscopy with a non-invasive but equally accurate instrument. A Pubmed, Web of Knowledge, and Scopus search of original articles as potential MH markers in adults, published between January 2009 and March 2020, was conducted. Finally, 84 eligible studies were identified. The most frequently studied fecal marker was calprotectin (44 studies), with areas under the curves (AUCs) ranging from 0.70 to 0.99 in ulcerative colitis (UC) and from 0.70 to 0.94 in Crohn`s disease (CD), followed by lactoferrin (4 studies), matrix metalloproteinase-9 (3 studies), and lipocalin-2 (3 studies). The most frequently studied serum marker was C-reactive protein (30 studies), with AUCs ranging from 0.60 to 0.96 in UC and from 0.64 to 0.93 in CD. Fecal calprotectin is an accurate MH marker in IBD in adults; however, it cannot replace endoscopy and the application of calprotectin is hampered by the lack of standardization concerning the cut-off value. Other markers are either not sufficiently accurate or have not been studied extensively enough.

Incorporating Fecal Calprotectin Into Clinical Practice for Patients With Moderate-to-Severely Active Ulcerative Colitis Treated With Biologics or Small-Molecule Inhibitors

INTRODUCTION

We applied the Grading of Recommendations, Assessment, Development, and Evaluation framework to evaluate the performance of fecal calprotectin (FC) as an alternative to endoscopy in patients with moderate-to-severe ulcerative colitis (UC) treated with a biologic agent or tofacitinib.

METHODS

Individual participant data from the trials of infliximab, golimumab, vedolizumab, and tofacitinib for UC were pooled to generate prevalence of endoscopic activity (Mayo endoscopy score) across different combinations of the rectal bleeding score (RBS) and stool frequency score (SFS). These estimates were then combined with the data from an updated systematic review of the operating properties of FC to generate clinical scenario-specific assessments of the performance of FC as a predictor of endoscopic disease activity. A prespecified threshold of acceptability for false-negative (FN) and false-positive (FP) test results was set at 5%.

RESULTS

For patients with UC achieving RBS 0 + SFS 0/1, FC ≤ 50 μg/g may avoid endoscopy in 50% patients with a FN rate <5%. Similarly, for patients with RBS 2/3 + SFS 2/3, FC ≥ 250 μg/g potentially avoids endoscopy in approximately 50% patients with an FP rate <5%. The greatest uncertainty in the diagnostic performance for FC was observed in patients with UC achieving RBS 0 but having SFS 2/3, where FN and FP rates were consistently >10%, and endoscopic evaluation may be warranted.

DISCUSSION

Two clinical scenarios were identified where FC can be used with confidence for monitoring treatment response to biologics or tofacitinib in patients with UC without the requirement for endoscopy.

Prostaglandin E-major urinary metabolite versus fecal immunochemical occult blood test as a biomarker for patient with ulcerative colitis

Background

Prostaglandin E-major urinary metabolite (PGE-MUM) may be a novel biomarker for evaluating disease activity in ulcerative colitis (UC). We compared its usefulness to that of the fecal immunochemical occult blood test (FIT).

Methods

PGE-MUM and FIT measurements were performed of 92 urinary and fecal samples obtained from 60 patients with UC. Endoscopic activity was determined by Mayo endoscopic subscore (eMayo) and Ulcerative Colitis Endoscopic Index of Severity (UCEIS) score.

Results

PGE-MUM levels and FIT results showed a significant correlation with respect to eMayo (P <  0.001 and P < 0.001, respectively), and there was a significant difference in PGE-MUM values between the groups below eMayo1 and above eMayo2 (P = 0.012). Both biomarkers were significantly correlated with the UCEIS score (P < 0.001 and P < 0.001, respectively), and the PGE-MUM values were significantly different between groups below UCEIS1 and above UCEIS2 (P = 0.012). PGE-MUM and FIT were significantly correlated with eMayo in the group with a disease duration < 5 years (P = 0.041 and P < 0.001, respectively). Although PGE-MUM and eMayo differed significantly between groups over 5 years (P = 0.012), FIT was not correlated with eMayo (P = 0.101).

Conclusions

PGE-MUM is useful as a biomarker as FIT for evaluating the endoscopic activity, particularly in long-term affected patients with UC.

Review article: faecal calprotectin and histologic remission in ulcerative colitis

BACKGROUND

Histologic healing is emerging as a new therapeutic goal in both routine practice and clinical trials in ulcerative colitis (UC). However, it requires repeated endoscopies and biopsies. Faecal calprotectin is a non-invasive marker of mucosal healing (endoscopic and histologic healing).

AIM

To conduct a systematic review to clarify the correlation between faecal calprotectin levels and histologic activity in UC patients.

METHODS

We searched PubMed/MEDLINE, EMBASE and Web of Science through September 2019 to identify studies in patients with confirmed diagnosis of UC, reporting the correlation between faecal calprotectin levels and histologic analysis.

RESULTS

Twelve studies enrolling 1168 patients were included in the final review. Histologic remission was defined according to nonvalidated scores in five articles and using partially validated scores in seven articles. Faecal calprotectin values were measured in 6 of 12 studies (50%) with the same kit, while the remaining six studies adopted individually different kits. A clear correlation between faecal calprotectin levels and histology was showed in all included studies. Eleven different faecal calprotectin cut-off points were identified to distinguish histological remission from histological activity, ranging from 40.5 to 250 μg/g.

CONCLUSIONS

Faecal calprotectin can be used to predict histologic remission in patients with UC, but the cut-off level varies across studies, according to the test used to measure this biomarker and according to the definition of histologic remission. Larger prospective studies using validated histologic indexes are needed to identify a globally accepted faecal calprotectin cut-off level to discriminate between histologic remission and histologically active disease.

Head to head comparison of two commercial fecal calprotectin kits as predictor of Mayo endoscopic sub-score and mucosal TNF expression in ulcerative colitis

BACKGROUND

Fecal calprotectin is widely used to monitor disease activity in patients with inflammatory bowel disease. Multiple commercial kits exist, however, since the analyses are not standardized, these kits cannot be used interchangeably. We aimed to perform a technical evaluation of two kits (Calpro from Calprolab, Norway and Calprest from Eurospital, Italy) and perform a tuning for detection of clinically relevant disease states in ulcerative colitis.

MATERIALS AND METHODS

For tuning against different clinical states a total of 116 patients with ulcerative colitis were recruited (67 of which were part of an earlier publication). For the technical evaluation an additional series of 80 random samples from the hospital lab were included. Technical evaluation was done by correlation and limits of agreement analysis; cut-off levels were explored by ROC analysis against clinically relevant actual states.

RESULTS

The technical evaluation revealed good correlation between assays, however a non-linear difference was found: At values below 200 mg/kg, no significant bias was found; in the interval 200-1000 mg/kg the Calprest assay measured on average 30% lower than Calpro; and at higher values Calprest measured 60% higher values than Calpro. Both assays predicted Mayo endoscopic score (MES) 0 (cutoff 28: sensitivity 0.38; specificity 0.82 for Calprest; cutoff 28: sensitivity 0.50; specificity 0.77 for Calpro), and MES 2-3 (cutoff 148: sensitivity 0.72; specificity 0.80 for Calprest; cutoff 208: sensitivity 0.64; specificity 0.80 for Calpro), but did not predict normalization of mucosal TNF transcript per se. A combination of calprotectin and MES predicted mucosal TNF transcript values reasonably well (Calpro: sensitivity 0.85, specificity 0.58; Calprest: sensitivity 0.85, specificity 0.61).

CONCLUSION

The Calpro and Calprest assays correlated well, but subtle differences were found, underlining the need for kit-specific cut-off values. Both kits were most precise in predicting active inflammation (MES 2-3), but less so for prediction of mucosal healing (MES 0) and normalization of mucosal TNF gene expression.

One-Hour Esophageal String Test: A Nonendoscopic Minimally Invasive Test That Accurately Detects Disease Activity in Eosinophilic Esophagitis

OBJECTIVES

Eosinophilic esophagitis (EoE), a chronic food allergic disease, lacks sensitive and specific peripheral biomarkers. We hypothesized that levels of EoE-related biomarkers captured using a 1-hour minimally invasive Esophageal String Test (EST) would correlate with mucosal eosinophil counts and tissue concentrations of these same biomarkers. We aimed to determine whether a 1-hour EST accurately distinguishes active from inactive EoE or a normal esophagus.

METHODS

In a prospective, multisite study, children and adults (ages 7-55 years) undergoing a clinically indicated esophagogastroduodenoscopy performed an EST with an esophageal dwell time of 1 hour. Subjects were divided into 3 groups: active EoE, inactive EoE, and normal esophageal mucosa. Eosinophil-associated protein levels were compared between EST effluents and esophageal biopsy extracts. Statistical modeling was performed to select biomarkers that best correlated with and predicted eosinophilic inflammation.

RESULTS

One hundred thirty-four subjects (74 children, 60 adults) with active EoE (n = 62), inactive EoE (n = 37), and patient controls with a normal esophagus (n = 35) completed the study. EST-captured eosinophil-associated biomarkers correlated significantly with peak eosinophils/high-power field, endoscopic visual scoring, and the same proteins extracted from mucosal biopsies. Statistical modeling, using combined eotaxin-3 and major basic protein-1 concentrations, led to the development of EoE scores that distinguished subjects with active EoE from inactive EoE or normal esophagi. Eighty-seven percent of children, 95% of parents, and 92% of adults preferred the EST over endoscopy if it provided similar information.

DISCUSSION

The 1-hour EST accurately distinguishes active from inactive EoE in children and adults and may facilitate monitoring of disease activity in a safe and minimally invasive fashion.

Can advanced endoscopic techniques for assessment of mucosal inflammation and healing approximate histology in inflammatory bowel disease?

The targets of therapy in inflammatory bowel disease have transformed in the last few years. The standard definition of mucosal healing assessed using white light standard definition endoscopy is being challenged because even when endoscopy suggests mucosal healing, the presence of histological activity can often still be observed. Of note, microscopic signs of inflammation correlate with clinical outcomes such as risk of relapse, hospitalization and colorectal cancer. Therefore, histological healing has increasingly become an important target to achieve. Advanced endoscopic technologies have been developed and many are starting to be adopted in daily clinical practice. They can provide a more detailed view of the mucosal and vascular architecture almost at the histology level, including crypt, vessel architecture and cellular infiltration. So, these can provide a more accurate definition of mucosal and histological healing. In this review we focus on new advanced endoscopic techniques, and how these have the potential to reduce the gap between histological and mucosal healing.

Galectin-3 Regulates Indoleamine-2,3-dioxygenase-Dependent Cross-Talk between Colon-Infiltrating Dendritic Cells and T Regulatory Cells and May Represent a Valuable Biomarker for Monitoring the Progression of Ulcerative Colitis

Galectin-3 regulates numerous biological processes in the gut. We investigated molecular mechanisms responsible for the Galectin-3-dependent regulation of colon inflammation and evaluated whether Galectin-3 may be used as biomarker for monitoring the progression of ulcerative colitis (UC). The differences in disease progression between dextran sodium sulphate-treated wild type and Galectin-3-deficient mice were investigated and confirmed in clinical settings, in 65 patients suffering from mild, moderate, and severe colitis. During the induction phase of colitis, Galectin-3 promoted interleukin-1β-induced polarization of colonic macrophages towards inflammatory phenotype. In the recovery phase of colitis, Galectin-3 was required for the immunosuppressive function of regulatory dendritic cells (DCs). Regulatory DCs in Galectin-3:Toll-like receptor-4:Kynurenine-dependent manner promoted the expansion of colon-infiltrated T regulatory cells (Tregs) and suppressed Th1 and Th17 cell-driven colon inflammation. Concentration of Galectin-3 in serum and stool samples of UC patients negatively correlated with clinical, endoscopic, and histological parameters of colitis. The cutoff serum values of Galectin-3 that allowed the discrimination of mild from moderate and moderate from severe colitis were 954 pg/mL and 580 pg/mL, respectively. Fecal levels of Galectin-3 higher than 553.44 pg/mL indicated attenuation of UC. In summing up, Galectin-3 regulates the cross-talk between colon-infiltrating DCs and Tregs and represents a new biomarker for monitoring the progression of UC.

Clinical value of fecal calprotectin

Inflammatory bowel disease (IBD) denotes a group of chronic incurable disorders characterized by relapsing-remitting inflammation of the gastrointestinal tract. IBD represents a growing global burden with a prevalence exceeding 0.3% in the Western world and an accelerating incidence in newly industrialized countries. The target for treating IBD has shifted in recent years from symptom control to mucosal healing (MH), which has been shown to be associated with favorable long-term outcomes. The gold standard for ascertaining MH is endoscopic assessment, but endoscopy is limited by its invasive nature, high cost, and finite availability. Surrogate biomarkers are therefore of great utility. Calprotectin, a cytosolic protein derived predominantly from neutrophils, is now widely used in this capacity. Calprotectin is found in various bodily fluids at concentrations proportional to the degree of inflammation, including in feces at levels roughly six times higher than in the blood. Fecal calprotectin (FCP) therefore reflects intestinal inflammation. Various assays, including point-of-care and home-based tests, are now available for measuring FCP. FCP is used for screening purposes, to aid in distinguishing inflammatory from non-inflammatory gastrointestinal conditions like irritable bowel syndrome (IBS), as well as in the monitoring of known IBD. The aims of this review are to provide an overview of the methods used to measure FCP and to review the evidence supporting the use of FCP in IBD, particularly as it pertains to screening, monitoring and predicting disease relapse.

Usefulness of transabdominal ultrasonography for assessing ulcerative colitis: a prospective, multicenter study

BACKGROUND

Transabdominal ultrasonography (US) has been reported to be a useful tool for evaluating ulcerative colitis (UC) although with less well-established data than for Crohn's disease. This prospective multicenter study aimed to establish the usefulness of US compared with colonoscopy (CS) for assessing disease extent and activity of UC.

METHODS

Altogether, 173 patients with UC were prospectively enrolled, among whom 156 were eligible for this study. All patients underwent US and CS within 2 days at five facilities. We divided the colon into six segments and examined each segment and the rectum using US and CS. US severity was graded 1-4 regarding bowel wall thickness, stratification, and ulceration. CS severity was also graded 1-4 according to Matts' endoscopic classification. Concordance between US and CS grades for all colonic segments was analyzed using kappa statistics. US and CS findings were also compared with the clinical disease activity index (CAI) and histological grade using Spearman's correlation coefficient.

RESULTS

There was moderate concordance between US and CS grades in all colonic segments (weighted κ = 0.55, p < 0.001). Concordance was rated moderate for each colonic segment but only slight for the rectum. The US grade was significantly correlated with the CAI score (r = 0.40, p < 0.001) and histological grade (r = 0.35, p < 0.001).

CONCLUSIONS

This prospective multicenter study showed moderate concordance between US and CS for assessing the disease activity of UC. Hence, US may be used more generally for evaluating UC in daily clinical practice.

Prediction of treatment outcome and relapse in inflammatory bowel disease

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

Clinical Parameters Correlate With Endoscopic Activity of Ulcerative Colitis: A Systematic Review

BACKGROUND & AIMS

Optimal management of patients with ulcerative colitis (UC) requires assessment of disease activity-usually by endoscopy, which is invasive, costly, and not risk free. We performed a systematic review to determine whether clinical symptoms correlate with findings from endoscopy assessments of patients with UC.

METHODS

We performed a systematic review of publication databases from January 1980 through July 2018 to identify clinical trials and observational studies reporting correlations among symptoms, disease activity index scores and/or patient reported outcomes (rectal bleeding and/or stool frequency), and endoscopic disease activity. Correlations were ascertained in patients with active vs inactive disease and by disease extent and treatment type. Risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 tool. Because of significant heterogeneity, meta-analysis was not possible. Results were synthesized qualitatively and systematically.

RESULTS

Our final analysis included 23 studies (1 randomized trial, 22 observational studies) comprising 3320 patients with UC. The studies used a variety of measures to assess clinical activity, endoscopic activity, and measures of correlation (sensitivity, specificity, correlation coefficients, area under the receiver operator curve). Overall, studies were at moderate-high risk of bias. Composite clinical measures, including rectal bleeding and stool frequency, had moderate to strong correlations with endoscopic disease activity; the absence of rectal bleeding identified patients with inactive disease with higher levels of sensitivity than normalization of stool frequency. In general, symptoms correlated more strongly with endoscopic activity in patients with left-sided colitis than extensive colitis. The effect of different medications on the correlation between clinical and endoscopic activity has not been well studied.

CONCLUSIONS

In a systematic review, we found a moderate to strong correlation between clinical activity, particularly the combination of rectal bleeding and stool frequency, and endoscopic activity in patients with UC. Although these clinical assessments could help prioritize patients for endoscopic evaluation in resource-limited settings, challenges associated with treating patients based on symptoms alone preclude adaptation of current management algorithms.

IBDoc Canadian User Performance Evaluation

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Aminosalicylates, thiopurines and methotrexate in inflammatory bowel disease: Is it possible to discontinue the treatment?

The current goals of treatment in inflammatory bowel disease, both Crohn's disease and ulcerative colitis, are to achieve clinical, endoscopic and ideally histological remission and improve the quality of life of these patients. Current therapies are effective in achieving remission in most cases, but there is a lack of clear guidelines on their optimal duration. This review aims to evaluate the current evidence on the withdrawal of therapy with 5-aminosalicylates, thiopurines and methotrexate. We also aim to identify which specific group of patients, while in remission and in the absence of risk factors, may be able to discontinue therapy without a significant risk of relapse.

Mucosal healing in inflammatory bowel disease: Expanding horizon

Management of inflammatory bowel diseases has witnessed paradigm shift from 5-aminosalicylic acid and glucocorticoids to various immunosuppressant and biological agents. Targets of therapy have also been changed drastically from symptomatic improvement to mucosal, histological healing, and recently transmural healing. Mucosal healing is associated with reduced need of steroid therapy, hospitalization, and surgery. However, whether mucosal healing alters the natural history of disease remains to be proven. Though assessment of mucosal healing is traditionally done by endoscopic examination, newer tests like fecal calprotectin, capsule endoscopy, and magnetic resonance enterography have also shown promising results. Various immunosuppressants and biologicals are the main therapy being used to achieve mucosal healing. This review focuses on the need for achieving mucosal healing, its long-term benefits, various methods and algorithm for diagnosis, and achievement of mucosal healing.

Defining Faecal Calprotectin Thresholds as a Surrogate for Endoscopic and Histological Disease Activity in Ulcerative Colitis-a Prospective Analysis

BACKGROUND

Faecal calprotectin [FCal] levels are used as a surrogate marker for mucosal inflammation, but thresholds for defining endoscopic or histological disease activity in ulcerative colitis [UC] remain unclear.

METHODS

Using validated indices, prospective measurements of FCal, symptoms [Simple Colitis Clinical Activity Index, SCCAI], endoscopic [Ulcerative Colitis Endoscopic Index of Severity, UCEIS] and histological activity [Nancy index] were made over 6 months in patients enrolled into the TrueColours UC web-based monitoring programme. Repeated measurements correlation was performed between FCal and SCCAI, UCEIS, and Nancy indices using definitions for remission and active disease [UCEIS: remission ≤1, active ≥4; Nancy: remission ≤1, active ≥2; combined criteria: remission UCEIS ≤1 and Nancy ≤1, active UCEIS ≥4 and Nancy ≥2]. Receiver operating characteristic curves investigated FCal thresholds after maximising sensitivity for active disease.

RESULTS

In 39 patients followed prospectively for 6 months, correlation coefficients between FCal and SCCAI, UCEIS, and Nancy indices were 0.271 (95% confidence interval [CI] 0.114-0.415), 0.741 [95% CI 0.289-0.922], and 0.876 [95% CI 0.605-0.965], respectively. Median FCal thresholds for remission using endoscopic, histological, or combined criteria were 71 μg/g [range 8-624], 91 μg/g [range 8-858], and 67 μg/g [range 8-479], respectively. The FCal threshold above which active disease was confirmed was 187 μg/g for UCEIS (area under the curve [AUC] 0.915), 72 μg/g for Nancy [AUC 0.824], and 187 μg/g for combined endoscopic and histological criteria [AUC 0.936].

CONCLUSIONS

Correlation between FCal and symptoms in UC is weak. In contrast, the correlation between FCal and endoscopic or histological activity is strong. An FCal ≥72 μg/g indicates histological inflammation [Nancy ≥2] and ≥187 μg/g indicates endoscopically active disease [UCEIS ≥4], whether combined with histopathology or not.

ACG Clinical Guideline: Ulcerative Colitis in Adults

Ulcerative colitis (UC) is an idiopathic inflammatory disorder. These guidelines indicate the preferred approach to the management of adults with UC and represent the official practice recommendations of the American College of Gastroenterology. The scientific evidence for these guidelines was evaluated using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) process. In instances where the evidence was not appropriate for GRADE, but there was consensus of significant clinical merit, "key concept" statements were developed using expert consensus. These guidelines are meant to be broadly applicable and should be viewed as the preferred, but not only, approach to clinical scenarios.

Practical fecal calprotectin cut-off value for Japanese patients with ulcerative colitis

AIM

To determine appropriate fecal calprotectin cut-off values for the prediction of endoscopic and histologic remission in Japanese patients with ulcerative colitis (UC).

METHODS

We performed a cross-sectional observational study of 131 Japanese patients with UC and measured fecal calprotectin levels by fluorescence enzyme immunoassay. The clinical activity of UC was assessed with the partial Mayo score (PMS). Relapse was defined as increase of PMS by 2 points or more in stool frequency or rectal bleeding subscore. The endoscopic and histologic activities of UC were evaluated in 50 patients within a 2-mo period from fecal sampling. Endoscopic activity was determined by Mayo endoscopic subscore, Rachmilewitz endoscopic index, and ulcerative colitis endoscopic index of severity. The histologic grade of inflammation was evaluated with biopsy specimens obtained from the endoscopically most severely inflamed site, according to the scheme by Matts grade and Riley’s score.

RESULTS

Fecal calprotectin levels varied from 1-20783 μg/g. There was a significant correlation between the partial Mayo score and fecal calprotectin levels (r = 0.548, P < 0.001). In 50 patients who underwent colonoscopy with biopsy, levels were significantly correlated with the Mayo endoscopic subscore (r = 0.574, P < 0.001), Rachmilewitz endoscopic index (r = 0.628, P < 0.001), ulcerative colitis endoscopic index of severity (r = 0.613, P < 0.001), Riley’s histologic score (r = 0.400, P = 0.006), and Matts grade (r = 0.586, P < 0.001). Receiver-operating characteristic analyses identified the best cut-off value for the prediction of endoscopic remission as 288 μg/g, with an area under the curve of 0.777 or 0.823, while that for histologic remission was 123 or 125 μg/g, with an AUC of 0.881 or 0918, respectively. Of the 131 study patients, 88 patients in clinical remission were followed up 6 mo. During the follow-up period, 19 patients relapsed. The best fecal calprotectin cut-off value for predicting relapse was 175 μg/g.

CONCLUSION

Fecal calprotectin is a predictive biomarker for endoscopic and histologic remission in Japanese patients with UC.

Fecal Calprotectin

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