Assessment of disease activity in ulcerative colitis by faecal calprotectin, a novel granulocyte marker protein

Fecal level of calprotectin identifies histologic inflammation in patients with ulcerative colitis in clinical and endoscopic remission

BACKGROUND & AIMS

Histologic recovery of patients with ulcerative colitis (UC) often is incomplete, even among those in clinical and endoscopic remission. Persistent active microscopic inflammation is associated with an increased risk of relapse and colorectal neoplasia. A high level of fecal calprotectin (FC) is a reliable marker of endoscopic lesions in patients with UC. We evaluated the accuracy of FC in identifying patients with UC in clinical and endoscopic remission who still have histologic features of inflammation.

METHODS

We performed a prospective observational study of 59 patients with UC in clinical and endoscopic remission undergoing colonoscopy. Several biopsy specimens were collected from each colonic segment. Endoscopic remission was defined as a Mayo endoscopic subscore with a grade of 0 or 1. Active histologic inflammation was defined by the presence of neutrophils infiltrating crypt epithelial cells. FC was determined by enzyme-linked immunosorbent assay analysis.

RESULTS

Eighteen patients (30.5%) showed evidence of active histologic inflammation. Patients with active histologic inflammation had a significantly higher median level of FC (278 μg/g; interquartile range, 136-696 μg/g) than those without active histologic inflammation (68 μg/g; interquartile range, 30-172 μg/g) (P = .002). In multivariate analysis, the FC and Mayo endoscopic subscore (0 or 1) were each independent predictors of histologic inflammation. The level of FC identified active histologic inflammation in patients in clinical and endoscopic remission, with an area under the receiver operator characteristic curve value of 0.754.

CONCLUSIONS

Histologic inflammation is common among patients with UC in clinical and endoscopic remission. Patients with histologic features of inflammation can be identified reliably based on their fecal level of calprotectin.

A prospective evaluation of the predictive value of faecal calprotectin in quiescent Crohn's disease

BACKGROUND

Faecal calprotectin (FC) is a non-invasive marker of gastrointestinal inflammation.

AIM

To determine whether higher FC levels in individuals with quiescent Crohn's disease are associated with clinical relapse over the ensuing 12 months.

METHODS

A single centre prospective study was undertaken in Crohn's disease patients in clinical remission. The receiver operating characteristic (ROC) curve for the primary endpoint of clinical relapse by 12 months, based on FC at baseline, was calculated. Kaplan-Meier curves of time to relapse were based on the resulting optimal FC cutoff for predicting relapse.

RESULTS

Of 97 patients recruited, 92 were either followed up for 12 months without relapsing, or reached the primary endpoint within that period. Of these, 10 (11%) relapsed by 12 months. Median FC was lower for non-relapsers, 96 μg/g (IQR 39-237), than for relapsers, 414 μg/g (IQR 259-590), (p=0.005). The area under the ROC curve to predict relapse using FC was 77.4%. An optimal cutoff FC value of 240 μg/g to predict relapse had sensitivity of 80.0% and specificity of 74.4%. Negative predictive value was 96.8% and positive predictive value was 27.6%, FC ≥240 μg/g was associated with likelihood of relapse by 12-months 12.18 (95% CI 2.55-58.2) times higher than lower values (p=0.002).

CONCLUSIONS

In this prospective dataset, FC is a useful tool to help identify quiescent Crohn's disease patients at a low risk of relapse over the ensuing 12 months. FC of 240 μg/g was the optimal cutoff in this cohort.

Fecal calprotectin concentration in neonatal necrotizing enterocolitis

PURPOSE

Among the many factors associated with acute intestinal mucosal infection, numerous studies have proposed the usefulness of fecal calprotectin. The aim of this study was to evaluate the usefulness of fecal calprotectin in the diagnosis of necrotizing enterocolitis (NEC).

METHODS

We collected 154 stool samples from 16 very low birth weight and premature newborns at the Konyang University Hospital neonatal intensive care unit or neonatal nursery. The stool samples were collected using the Calprest device, and the fecal calprotectin level was measured with the BÜHLMANN Calprotectin enzyme-linked immunosorbent assay kit.

RESULTS

Fecal calprotectin levels were significantly higher in the NEC group than in the non-NEC group (P=0.02). There was a significant positive linear relationship between the fecal calprotectin level and number of days after birth (P=0.00) in the gestational age <26 weeks group. There was a significant negative linear relationship between the calprotectin level and number of days after birth (P=0.03) in the gestational age ≥26 weeks and <30 weeks group. There was no difference in the calprotectin levels according to the type and method of feeding between the NEC and non-NEC groups.

CONCLUSION

Fecal calprotectin levels were significantly increased in premature infants with NEC. The fecal calprotectin test is a noninvasive, easy, and useful tool for the diagnosis of NEC.

Fecal calprotectin one year after ileocaecal resection for Crohn's disease--a comparison with findings at ileocolonoscopy

BACKGROUND AND AIMS

Ileocaecal resection for Crohn's disease is commonly performed. The severity of endoscopic lesions in the anastomotic area one year postoperatively is considered to reflect the subsequent clinical course. Fecal calprotectin (FC) has been shown to correlate with the findings at ileocolonoscopy in Crohn's disease. The objectives of this study were to assess whether the concentration of FC reflects the endoscopic findings one year after ileocaecal resection and to evaluate the variation of FC in individual patients during 6months prior to the ileocolonoscopy.

METHODS

Thirty patients with Crohn's disease and ileocaecal resection performed within one year were included. Stool samples were delivered monthly until an ileocolonoscopy was performed one year postoperatively.

RESULTS

One year after surgery the median values of FC were not significantly different between the patients in endoscopic remission (n=17) and the patients with an endoscopic recurrence (189 (75-364) vs 227 (120-1066)μg/g; p=0.25). However, most patients with low values were in remission and all patients with high (>600μg/g) calprotectin values had recurrent disease. The variability of the FC concentration was most pronounced in patients with diarrhea.

CONCLUSIONS

We found no statistical difference in the concentrations of calprotectin between patients in endoscopic remission and patients with a recurrent disease one year after ileocaecal resection for Crohn's disease. However, among the minority of patients with low or high values, FC indicated remission and recurrence, respectively. There was significant variation of the fecal calprotectin concentrations over time, which affects the utility of calprotectin in clinical practice.

Usefulness of a novel and rapid assay system for fecal calprotectin in pediatric patients with inflammatory bowel diseases

BACKGROUND AND AIM

Fecal calprotectin (FC) has become a reliable biomarker for intestinal inflammation in inflammatory bowel diseases (IBDs). However, a simple and rapid assay to replace conventional ELISA is necessary for wider use in clinical practice. In this study, we investigated the usefulness of a novel method for measuring FC using a colloidal gold aggregation (CGA) assay for assessing mucosal inflammation in pediatric IBDs.

METHODS

FC levels were determined by ELISA and CGA assay in 309 fecal samples (ulcerative colitis [UC]: 131; Crohn's disease [CD]: 121; healthy controls: 57). For endoscopic evaluation, the modified Matts' grading system for UC and the simple endoscopic score for CD were used.

RESULTS

A strong correlation was found between the FC values determined by the two methods (r = 0.98, P < 0.01). FC levels, determined by CGA assay, strongly correlated with the endoscopic score for UC (r = 0.70, P < 0.01) and CD (r = 0.58, P < 0.01). In the UC patients with endoscopic remission, the FC levels determined by CGA assay (median: 31.5 μg/g, n = 14) were as low as in healthy controls. For patients in clinical remission but showing an active status endoscopically, FC was more likely to be abnormal than commonly used laboratory markers.

CONCLUSIONS

Our simple and rapid assay system has excellent performance for assessing mucosal inflammation of IBDs and can be replaced for ELISA. Practical application of this assay system enables us to use FC measurement more widely in clinical practice.

Mapping of Crohn's disease outcomes to faecal calprotectin levels in patients maintained on biologic therapy

BACKGROUND

Faecal calprotectin (FC) is a sensitive marker of intestinal mucosal inflammation. The gold standard in Crohn's disease management is mucosal healing. The role of FC to support clinical practice in Crohn's disease is not yet defined.

AIMS

To determine, in patients with Crohn's disease established on biologic therapy: (1) the correlation between disease activity and FC levels, (2) whether FC can predict for relapse and (3) the sensitivity and specificity of the C-reactive protein (CRP) when compared with FC.

METHODS

In this retrospective, single-site study, Crohn's disease activity, clinical outcomes, FC and CRP of 76 patients established on biologic therapy were reviewed and mapped over time.

RESULTS

Patients were mapped for a median of 34 months (IQR 21-57.5). FC levels were determined every 7 (4-13) months on average. Mean FC in quiescent disease was 105 μg/g (SEM 19); in mild disease, 282 (SEM 71); in moderate disease, 611 (SEM 80) and in severe disease, 1314 (SEM 224) (p<0.001). In asymptomatic patients who relapsed at 6 months, the optimal FC, with an area under the curve of 0.886 (p<0.001), was 357.5. In discriminating quiescent from active disease (FC>100 μg/g) the sensitivity and specificity of CRP were 0.48 (0.36-0.61) and 0.73 (0.6-0.85), and in mild from moderate or active disease (FC>250 μg/g), 0.60 (0.43-0.74) and (0.72 (0.60-0.82).

CONCLUSIONS

FC is an accurate marker of Crohn's disease activity and predicts for relapse, thus providing the clinician time to optimise therapy. FC is a more sensitive marker of Crohn's disease activity than CRP.

Clinical and histopathological correlations of fecal calprotectin release in colorectal carcinoma

AIM: To determine calprotectin release before and after colorectal cancer operation and compare it to tumor and histopathological parameters.

METHODS: The study was performed on patients with diagnosed colorectal cancer admitted for operation. Calprotectin was measured in a single stool sample before and three months after the operation using an enzyme-linked immunosorbent assay (ELISA). Calprotectin levels greater than or equal to 50 μg/g were considered positive. The compliance for collecting stool samples was assessed and the value of calprotectin was correlated to tumor and histopathological parameters of intra- and peri-tumoral inflammation. Surgical specimens were fixed in neutral buffered formalin and stained with hematoxylin and eosin. Staging was performed according to the Dukes classification system and the 7^th edition tumor node metastasis classification system. Intra- and peri-tumoral inflammation was graded according to the Klintrup criteria. Immunohistochemical quantification was performed for MPO, CD45R0, TIA-1, CD3, CD4, CD8, CD57, and granzyme B. Statistical significance was measured using Wilcoxon signed rank test, Kruskal Wallis test and Spearman’s rank correlation coefficient as appropriate.

RESULTS: Between March 2009 and May 2011, 80 patients with colorectal cancer (46 men and 34 women, with mean age of 71 ± 11.7 years old) were enrolled in the study. Twenty-six patients had rectal carcinoma, 29 had left-side tumors, 23 had right-side tumors, and 2 had bilateral carcinoma. In total, 71.2% of the patients had increased levels of calprotectin before the operation (median 205 μg/g, range 50-2405 μg/g) and experienced a significant decrease three months after the operation (46 μg/g, range 10-384 μg/g, P < 0001). The compliance for collecting stool samples was 89.5%. Patients with T3 and T4 tumors had significantly higher values than those with T1 and T2 cancers (P = 0.022). For all other tumor parameters (N, M, G, L, V, Pn) and location, no significant difference in calprotectin concentration was found. Furthermore, the calprotectin levels and histological grading of both peri- and intra-tumoral inflammation was not correlated. Additional testing with specific markers for lymphocytes and neutrophils also revealed no statistically significant correlation.

CONCLUSION: Fecal calprotectin decreases significantly after colorectal cancer operation. Its value depends exclusively on the individual T-stage, but not on other tumor or histopathological parameters.

Comparison of three tests for faecal calprotectin in children and young adults: a retrospective monocentric study

OBJECTIVE

Faecal calprotectin is used as a sensitive marker for gastrointestinal mucosal inflammation. We compared the performance of three different assays in a large cohort of symptomatic paediatric patients.

DESIGN

Retrospective monocentric study.

SETTING

Inpatients and outpatients of a tertiary referral centre for paediatric gastroenterology.

PARTICIPANTS

304 symptomatic patients (163 males, aged 2-20 years) with active inflammatory bowel disease (IBD/A, n=130), IBD in clinical remission (IBD/R, n=62), other intestinal diseases (n=45) and controls without identified intestinal disease (n=67).

INTERVENTIONS

Calprotectin was measured in homogenised faecal samples with three tests (A: EliA Calprotectin, Phadia AB, Sweden; B: PhiCal, Calpro AS, Norway; C: EK-Cal, Bühlmann Laboratories, Switzerland).

OUTCOMES

Concordance between tests was calculated using Kendall's τ coefficient.

RESULTS

IBD/A and controls were correctly classified as 97.7%/82.1% (A), 97.7%/85.1% (B) and 98.4%/62.7% (C; not significant). Test C tended to have higher calprotectin values with a lower specificity compared to tests A and B. The concordance between two tests was 0.835 for tests A and B, 0.782 for tests A and C and 0.765 for tests B and C.

CONCLUSIONS

All three tests are very sensitive for detecting mucosal inflammation, but major differences exist between specificity and absolute values. It is highly advisable to use the test of the same manufacturer for follow-up and to monitor for disease activity.

Stool calprotectin in necrotizing enterocolitis

Background:

Calprotectin is a 36 kDa protein present in the cytoplasm of the neutrophil has antimicrobial and apoptosis inducing activities. In vitro studies have shown that calprotectin inhibits the growth of various microorganisms. Necrotizing enterocolitis (NEC) remains one of the leading causes of morbidity and mortality in neonatal intensive care units (NICU), affecting up to 5% of premature infants. Fecal calprotectin is resistant to degradation and has been proposed as a useful marker of gastrointestinal inflammation.

Objective:

The objective of the present study is to evaluate fecal calprotectin concentrations in NEC.

Study Design:

Fifteen neonates with a clinical diagnosis of NEC were studied; they admitted at NICU of Zagazig University Hospital. In addition, 20 age sex matched neonates fed all caloric requirement served as the control group. All neonates were subjected to history taking, clinical examination, laboratory investigations (complete blood count, C-reactive protein) and determination of stool calprotectin.

Results:

There was a highly significant increase in fecal calprotectin in patients than control and there was a highly significant increase in its fecal level in died patients than living one. Also significant increase in fecal calprotectin level with increasing severity of NEC.

Conclusion:

Fecal calprotectin measurements could be a valuable tool for the investigation of preterm and full term infants suspected of having NEC.

Fecal calprotectin in healthy children

Calprotectin is a protein found in the cytosol of inflammatory cells and is a marker of the presence and the degree of inflammation in the bowel system. Calprotectin in feces has great diagnostic value in the matter of inflammatory bowel disease (IBD). In feces, the protein is stable up to seven days, and since the protein can easily be measured with an ELISA, the use of fecal calprotectin (FC) means no invasive measures. For adults and children over 4 years, a cut-off level of 50 mg/kg has been well established for diagnostic purposes. Because previous studies have proven that children under the age of four in general have higher FC values than older children and adults, there is a need for a cut-off level for this age group. In order to establish that, the normal values for FC in children from 0-4 years were investigated. Some 75 stool samples from healthy children were collected and the levels of FC were analyzed. The results were compared to 157 pediatric cases where FC analysis had been performed for diagnostic purposes. As a result, three cut-off levels were established based on the 97.5% percentiles of FC in different age groups: 538 mg/kg (1 < 6 months), 214 mg/kg (6 months < 3 years) and 75 mg/kg (3 < 4 years).

Upregulation of circulating components of the alternative renin-angiotensin system in inflammatory bowel disease: A pilot study

INTRODUCTION

The relationship between intestinal inflammation and circulating components of the renin-angiotensin system (RAS) is poorly understood.

MATERIALS AND METHODS

Demographic and clinical data were obtained from healthy controls and patients with inflammatory bowel disease (IBD). Plasma concentrations of the classical RAS components (angiotensin-converting enzyme (ACE) and angiotensin II (Ang II)) and alternative RAS components (ACE2 and angiotensin (1-7) (Ang (1-7))) were analysed by radioimmuno- and enzymatic assays. Systemic inflammation was assessed using serum C-reactive protein (CRP), white cell count, platelet count and albumin, and intestinal inflammation by faecal calprotectin.

RESULTS

Nineteen healthy controls (11 female; mean age 38 years, range 23-68), 19 patients with Crohn's disease (11 female; aged 45 years, range 23-76) and 15 patients with ulcerative colitis (6 female; aged 42 years, 26-64) were studied. Circulating classical RAS component levels were similar across the three groups, whereas ACE2 activity and Ang (1-7) concentrations were higher in patients with IBD compared to controls (ACE2: 21.5 vs 13.3 pmol/ml/min, p<0.05; Ang (1-7): 22.8 vs 14.1 pg/ml, p<0.001). Ang (1-7) correlated weakly with platelet and white cell counts, but not calprotectin or CRP, in patients with IBD.

CONCLUSIONS

Circulating components of the alternative RAS are increased in patients with IBD.

Fecal biomarkers of intestinal health and disease in children

The identification of various fecal biomarkers has provided insight into the intestinal milieu. Most of these markers are associated with the innate immune system of the gut, apart from the more novel M2-pyruvate kinase. The innate immunity of the gut plays a role in maintaining a fine balance between tolerance to commensal bacteria and immune response to potential pathogens. It is a complex system, which comprises of multiple elements, including antimicrobial peptides (e.g., defensins, cathelicidins, lactoferrin, and osteoprotegerin), inflammatory proteins (e.g., calprotectin and S100A12), and microbial products (e.g., short-chain fatty acids). Dysfunction of any component can lead to the development of intestinal disease, and different diseases have been associated with different fecal levels of these biomarkers. Each fecal biomarker provides information on specific biological and disease processes. Therefore, stool quantification of these biomarkers provides a non-invasive method to define potential pathways behind the pathogenesis of diseases and can assist in the assessment and diagnosis of various gastrointestinal conditions. The abovementioned fecal biomarkers and their role in intestinal health and disease will be reviewed in this paper with a pediatric focus.

Mucosal healing in inflammatory bowel disease: treatment efficacy and predictive factors

In recent years mucosal healing has emerged as an important therapeutic goal for patients with inflammatory bowel disease. Growing evidence suggests that achieving mucosal healing can improve patient outcomes and, potentially, alter the course of the disease. Drugs currently used in the management of inflammatory bowel disease are potentially able of inducing and maintaining mucosal healing, but the effect size is difficult to assess because of different definitions of mucosal healing, differences in study designs, and timing of endoscopic evaluation. Mucosal healing has been studied extensively in the biologic era. Data available from different sources, such as controlled trials and observational studies, show that anti-TNFα therapies can induce rapid and sustained mucosal healing in a variable percentage of patients with Crohn's disease and ulcerative colits. No controlled study has been designed to identify possible predictors of mucosal healing. Some clinical characteristics such as extensive disease, young age at diagnosis, and smoking status may be predictive of a more aggressive clinical course and, presumably, of a reduced clinical and endoscopic response to therapy. Changes and normalization of C-reactive protein and faecal calprotectin may be useful tools to predict outcomes, guide the timing for endoscopic evaluation and, possibly, reduce the need of endoscopic evaluation in assessing mucosal healing.

Diagnostics and prognostics of inflammatory bowel disease with fecal neutrophil-derived biomarkers calprotectin and lactoferrin

Crohn's disease (CD), ulcerative colitis (UC), and colitis unclassified, collectively defined as inflammatory bowel disease (IBD), are the consequence of chronic inflammatory reactions in the gastrointestinal tissue. Endoscopy with biopsies is the mainstay in the diagnosis of this inflammation and is also important in the assessment of disease activity and monitoring of treatment. Furthermore, mucosal healing is increasingly becoming a therapeutic target for treatment of IBD and the golden standard of assessing it is endoscopy. However, due to the costs, invasiveness, and to limited endoscopic capacity, the need is strong for reliable surrogate markers of intestinal inflammation. Bowel contents, being in close contact with intestinal mucosa, can take up molecules that are measurable from stool samples and thus can serve as markers of inflammation. The fecal neutrophil-derived biomarkers, especially calprotectin and lactoferrin, have several features of an ideal test for detecting intestinal inflammation: they are noninvasive, simple, and low in cost. The utility of these biomarkers in distinguishing IBD from noninflammatory conditions such as irritable bowel syndrome is well documented. They correlate closely with endoscopic activity both in CD and UC. They allow serial monitoring of disease activity and of treatment success, and can even serve in predicting clinical relapse in unsymptomatic patients or sustained remission after induction with TNF-α-blocking agents. In this review an overview will be given to the role of fecal neutrophil-derived biomarkers calprotectin and lactoferrin in diagnostics and prognostics of IBD.

Biomarkers in management of inflammatory bowel disease

In recent years the use of faecal and serologic biomarkers has been evaluated in the diagnosis and management of inflammatory bowel disease (IBD). Faecal calprotectin (FC) has been proposed as a surrogate marker for intestinal inflammation; elevated concentrations in IBD patients have been confirmed in numerous studies. Already available rapid calprotectin tests help to differentiate between IBD and irritable bowel syndrome. Faecal calprotectin greatly correlates with endoscopic activity scales and reflects the mucosal healing; thus in patients in clinical remission high levels of it correlate with increased risk of disease relapse in the following 12 months. Adapting the calprotectin assay as a screening test before colonoscopy enables a significant reduction in endoscopic procedures. ANCA/ASCA antibodies have been used in IBD diagnosis and to distinguish CD from ulcerative colitis (UC). Lactoferrin and S100A12 protein were also used to assess the disease activity. This review aims to present the actual potential of biomarker assays for faster diagnosis of IBD and their ability to monitor the disease course, predict exacerbations and improve the way IBD is managed.

Symptoms of irritable bowel syndrome in patients with inflammatory bowel disease: examining the role of sub-clinical inflammation and the impact on clinical assessment of disease activity

BACKGROUND

Symptoms compatible with irritable bowel syndrome (IBS) are frequently present in patients with inflammatory bowel disease (IBD); however, the cause of this phenomenon is unclear.

AIM

To determine the different contributions of 'true IBS' and sub-clinical inflammation in producing IBS-type symptoms in IBD patients, and to ascertain the impact these symptoms have on the clinical assessment of IBD activity.

METHODS

In this cross-sectional study, 169 IBD patients completed questionnaires to assess disease activity, presence of IBS-type symptoms, and levels of anxiety and depression. Stool samples were collected for analysis of faecal calprotectin (FC).

RESULTS

IBS-type symptoms were significantly more common in female patients (OR = 4.64, 1.55-13.88) and were associated with higher levels of anxiety (OR = 1.11, 1.01-1.21). There was no statistical difference between the FC levels of patients in clinical remission with IBS-type symptoms compared with those without (median values = 111 μg/g vs. 45.5 μg/g respectively, P = 0.171). The prevalence of IBS-type symptoms in patients with a normal FC level was 31%.

CONCLUSIONS

A substantial number of IBD patients with normal faecal calprotectin level experience IBS-type symptoms. These patients exhibit similar features to people diagnosed with IBS in the general community, suggesting that the conditions are not mutually exclusive and may coexist in a considerable number of IBD patients. A systematic diagnostic approach is required to assess IBD patients with IBS-type symptoms as sub-clinical inflammation may play a role in a proportion of cases.

Serum calprotectin concentrations in dogs with idiopathic inflammatory bowel disease

OBJECTIVE

To measure serum calprotectin concentration in dogs with inflammatory bowel disease (IBD) before and after initiation of treatment and evaluate its correlation with a clinical scoring system (canine IBD activity index), serum canine C-reactive protein concentration, and severity of histopathologic changes.

ANIMALS

34 dogs with idiopathic IBD and 139 healthy control dogs.

PROCEDURES

From dogs with IBD, blood samples were collected immediately before (baseline) and 3 weeks after initiation of 1 of 2 treatments: prednisone (1 mg/kg, PO, q 12 h; n = 21) or a combination of prednisone and metronidazole (10 mg/kg, PO, q 12 h; 13). Blood samples were collected once from each of the control dogs. For all samples, serum calprotectin concentration was determined via radioimmunoassay.

RESULTS

Mean serum calprotectin concentrations for dogs with IBD at baseline (431.1 μg/L) and 3 weeks after initiation of treatment (676.9 μg/L) were significantly higher, compared with that (219.4 μg/L) for control dogs, and were not significantly correlated with the canine IBD activity index, serum C-reactive protein concentration, or severity of histopathologic changes. The use of a serum calprotectin concentration of ≥ 296.0 μg/L as a cutoff had a sensitivity of 82.4% (95% confidence interval, 65.5% to 93.2%) and specificity of 68.4% (95% confidence interval, 59.9% to 76.0%) for distinguishing dogs with idiopathic IBD from healthy dogs.

CONCLUSIONS AND CLINICAL RELEVANCE

Serum calprotectin concentration may be a useful biomarker for the detection of inflammation in dogs, but the use of certain drugs (eg, glucocorticoids) appears to limit its clinical usefulness.

A new rapid quantitative test for fecal calprotectin predicts endoscopic activity in ulcerative colitis

BACKGROUND

Fecal calprotectin (FC) determined by the enzyme-linked immunosorbent assay (ELISA) test has been proposed as a promising biomarker of endoscopic activity in ulcerative colitis (UC). However, data on its accuracy in predicting endoscopic activity is scarce. Besides, FC determined by the quantitative-point-of-care test (FC-QPOCT) that provides rapid and individual results could optimize its use in clinical practice. The aims of our study were to evaluate the ability of FC to predict endoscopic activity according to the Mayo score in patients with UC when determined by FC-QPOCT and to compare it with the ELISA test (FC-ELISA).

METHODS

FC was determined simultaneously by FC-ELISA and FC-QPOCT in patients with UC undergoing colonoscopy. Clinical disease activity and endoscopy were assessed according to the Mayo score. Blood tests were taken to analyze serological biomarkers.

RESULTS

A total of 146 colonoscopies were performed on 123 patients with UC. FC-QPOCT correlated more closely with the Mayo endoscopic subscore (Spearman's correlation coefficient rank r = 0.727, P < 0.001) than clinical activity (r = 0.636, P < 0.001), platelets (r = 0.381, P < 0.001), leucocytes (r = 0.300, P < 0.001), and C-reactive protein (r = 0.291, P = 0.002). The prediction of "endoscopic remission" (Mayo endoscopic subscore ≤1) with FC-QPOCT (280 µg/g) and FC-ELISA (250 µg/g) presented an area under the curve of 0.906 and 0.924, respectively. The interclass correlation index between both tests was 0.904 (95% confidence interval, 0.864-0.932; P < 0.001).

CONCLUSIONS

FC determined by QPOCT was an accurate surrogate marker of "endoscopic remission" in UC and presented a good correlation with the FC-ELISA test.

Neopterin is a novel reliable fecal marker as accurate as calprotectin for predicting endoscopic disease activity in patients with inflammatory bowel diseases

BACKGROUND

Fecal biomarkers have emerged as an important tool for assessing and monitoring disease activity in patients with inflammatory bowel diseases (IBDs). We performed a prospective head-to-head comparison of the diagnostic accuracy of both fecal calprotectin (fCal) and neopterin (fNeo), and serum C-reactive protein in predicting endoscopic disease severity in patients with IBD.

METHODS

A total of 133 consecutive patients with IBD (78 Crohn's disease [CD] and 55 ulcerative colitis [UC]) undergoing a colonoscopy provided fecal samples for the measurement of fCal and fNeo concentrations and a blood sample for the serum C-reactive protein measurement. Endoscopic disease activities were scored independently according to the Simple Endoscopic Score for CD in patients with CD and to the Rachmilewitz Index in patients with UC. The respective performances of the fecal markers with respect to endoscopic disease severity were assessed by computing correlations, sensitivities, specificities, and overall accuracies at adjusted cutoffs and also test operating characteristics.

RESULTS

The fCal and fNeo concentrations differed significantly in clinically and endoscopically active IBD when compared with those in patients with inactive disease. Both fCal and fNeo concentrations correlated closer with endoscopic scores in UC (r = 0.75 and r = 0.72, respectively; P < 0.0001 for both) than in CD (r = 0.53 and r = 0.47, respectively; P < 0.0001 for both). Using cutoffs of 250 μg/g for fCal and 200 pmol/g for fNeo, both fecal markers had similar overall accuracies to predict endoscopic activity in patients with CD (74%) and also a higher and similar accuracies (88% and 90%, respectively) in patients with UC, whereas accuracies of C-reactive protein were slightly lower in patients with CD and UC.

CONCLUSIONS

The fNeo is a novel reliable surrogate biomarker with the potential to identify patients with IBD with active mucosal lesions and represents an alternative marker as accurate as fCal to predict and monitor the severity of mucosal damages in patients with IBD.

Fecal MMP-9: a new noninvasive differential diagnostic and activity marker in ulcerative colitis

BACKGROUND

Ulcerative colitis (UC) is characterized by frequent relapses, with the presence of colorectal inflammation and mucosal lesions. Matrix-metalloprotease 9 (MMP-9) is elevated in colonic biopsies, urine, and blood plasma of UC patients. MMP-9 has been suggested as a predictor of UC in the urine of children; however, 20% of the controls tested positive. So far, fecal MMP-9 levels have never been measured. Our aims were: 1) to compare fecal MMP-9 levels in UC patients to control subjects and a functional gastrointestinal disorder characterized by diarrhea (IBS-D); 2) to test the correlation between UC disease activity and fecal levels of MMP-9; and 3) to correlate fecal MMP-9 levels with a known fecal marker of UC activity, calprotectin.

METHODS

UC (n = 47), IBS-D (n = 23) patients, and control subjects (n = 24) provided fecal samples for MMP-9 analysis. In UC patients, disease severity was evaluated by the Mayo score. Fecal MMP-9 and calprotectin levels were measured by enzyme-linked immunosorbent assay and lateral flow assay, respectively.

RESULTS

MMP-9 was undetectable or ≤0.22 ng/mL in the feces of all controls and IBS-D patients. In UC patients, fecal MMP-9 levels significantly correlated with the overall Mayo score (P < 0.001), the endoscopic score (P < 0.001), and the serum C-reactive protein levels (P = 0.002). Additionally, in UC patients fecal MMP-9 levels showed a significant correlation with a known disease activity marker, fecal calprotectin (P = 0.014).

CONCLUSIONS

These results highlight fecal MMP-9 as a useful tool in the differential diagnosis of diarrheic disorders and in the noninvasive evaluation of disease activity and mucosal healing in UC.

Fecal calprotectin more accurately reflects endoscopic activity of ulcerative colitis than the Lichtiger Index, C-reactive protein, platelets, hemoglobin, and blood leukocytes

BACKGROUND

The correlation between noninvasive markers with endoscopic activity according to the modified Baron Index in patients with ulcerative colitis (UC) is unknown. We aimed to evaluate the correlation between endoscopic activity and fecal calprotectin (FC), C-reactive protein (CRP), hemoglobin, platelets, blood leukocytes, and the Lichtiger Index (clinical score).

METHODS

UC patients undergoing complete colonoscopy were prospectively enrolled and scored clinically and endoscopically. Samples from feces and blood were analyzed in UC patients and controls.

RESULTS

We enrolled 228 UC patients and 52 healthy controls. Endoscopic disease activity correlated best with FC (Spearman's rank correlation coefficient r = 0.821), followed by the Lichtiger Index (r = 0.682), CRP (r = 0.556), platelets (r = 0.488), blood leukocytes (r = 0.401), and hemoglobin (r = -0.388). FC was the only marker that could discriminate between different grades of endoscopic activity (grade 0, 16 [10-30] μg/g; grade 1, 35 [25-48] μg/g; grade 2, 102 [44-159] μg/g; grade 3, 235 [176-319] μg/g; grade 4, 611 [406-868] μg/g; P < 0.001 for discriminating the different grades). FC with a cutoff of 57 μg/g had a sensitivity of 91% and a specificity of 90% to detect endoscopically active disease (modified Baron Index ≥ 2).

CONCLUSIONS

FC correlated better with endoscopic disease activity than clinical activity, CRP, platelets, hemoglobin, and blood leukocytes. The strong correlation with endoscopic disease activity suggests that FC represents a useful biomarker for noninvasive monitoring of disease activity in UC patients.

Utility of faecal calprotectin analysis in adult inflammatory bowel disease

The inflammatory bowel diseases (IBD), Crohn’s disease and ulcerative colitis, are chronic relapsing, remitting disorders. Diagnosis, along with assessment of disease activity and prognosis present challenges to managing clinicians. Faecal biomarkers, such as faecal calprotectin, are a non-invasive method which can be used to aid these decisions. Calprotectin is a calcium and zinc binding protein found in the cytosol of human neutrophils and macrophages. It is released extracellularly in times of cell stress or damage and can be detected within faeces and thus can be used as a sensitive marker of intestinal inflammation. Faecal calprotectin has been shown to be useful in the diagnosis of IBD, correlates with mucosal disease activity and can help to predict response to treatment or relapse. With growing evidence supporting its use, over the last decade this faecal biomarker has significantly changed the way IBD is managed.

Effect of bowel cleansing for colonoscopy on fecal calprotectin levels in pediatric patients

The recent development of easily applicable fecal surrogate markers of intestinal inflammation, such as fecal calprotectin (FC), has provided a new means for objectively assessing disease activity in patients with chronic inflammatory bowel disease. Because the use of these markers is about to emerge, it is important to be aware of the possible limitations of measurements. We assessed levels of FC during bowel cleansing. In patients with high FC levels at baseline, the values measured during bowel cleansing varied considerably, remaining high or even returning to normal. Thus, stool sampling for FC assessment is not recommended during bowel preparation for colonoscopy.

Improved outcomes with quality improvement interventions in pediatric inflammatory bowel disease

OBJECTIVES

Variations in chronic illness care are common in our health care system and may lead to suboptimal outcomes. Specifically, inconsistent use and suboptimal medication dosing have been demonstrated in the care of patients with inflammatory bowel disease (IBD). Quality improvement (QI) efforts have improved outcomes in conditions such as asthma and diabetes mellitus, but have not been well studied in IBD. We hypothesized that QI efforts would lead to improved outcomes in our pediatric IBD population.

METHODS

A QI team was formed within our IBD center in 2005. By 2007, we began prospectively capturing physician global assessment (PGA) and patient-reported global assessment. Significant QI interventions included creating evidence-based medication guidelines, joining a national QI collaborative, initiation of preclinic planning, and monitoring serum 25-hydroxyvitamin D.

RESULTS

From 2007 to 2010, 505 patients have been followed at our IBD center. During this time, the frequency of patients in clinical remission increased from 59% to 76% (P < 0.05), the frequency of patients who report that their global assessment is >7 increased from 69% to 80% (P < 0.05), and the frequency of patients with a Short Pediatric Crohn's Disease Activity Index (sPCDAI) <15 increased from 60% to 77% (P < 0.05). The frequency of repeat steroid use decreased from 17% to 10% (P < 0.05). We observed an association between the use of a vitamin D supplement (P = 0.02), serum 25-hydroxyvitamin D (P < 0.05), and quiescent disease activity.

CONCLUSIONS

Our results show that significant improvements in patient outcomes are associated with QI efforts that do not rely on new medication or therapies.

Fecal calprotectin as a correlative marker in clinical severity of infectious diarrhea and usefulness in evaluating bacterial or viral pathogens in children

BACKGROUND

Calprotectin is a marker associated with intestinal inflammation. The aim of this study is to explore the diagnostic value of fecal calprotectin in predicting bacterial/viral diarrhea and the application of fecal calprotectin in the clinical course of infectious diarrhea.

METHODS

Patients ages from 3 months to 10 years with infectious diarrhea were enrolled, and from each patient, 2 to 3 stool samples were collected. Fecal calprotectin levels were determined by enzyme-linked immunosorbent assay and compared by pathogen and disease activity. A univariate linear regression was used to determine the correlation between fecal calprotectin and the clinical parameters, and generalized estimating equations (GEEs) were used for the time course analyses.

RESULTS

The data include 451 evaluations for 153 individuals across 3 different time points. The fecal calprotectin level was higher in patients with Salmonella infection (median with range 765 [252-1246] μg/g) or Campylobacter infection (689 [307-1046] μg/g) compared with patients with rotavirus infection (89 [11-426] μg/g), norovirus infection (93 [25-405] μg/g), or adenovirus infection (95 [65-224] μg/g). Fecal calprotectin concentrations were elevated in patients with severe (843 [284-1246] μg/g) or moderate (402 [71-995] μg/g) disease activity compared with those with mild (87 [11-438] μg/g) disease activity (P < 0.05). GEE analysis suggests that fecal calprotectin is correlated with clinical severity (e.g., Vesikari score) and may provide information for disease management.

CONCLUSIONS

Fecal calprotectin levels increased during bacterial infection and as disease severity increased, and its levels on the initial evaluation and follow-up visit are correlated with clinical severity. Fecal calprotectin may be a useful marker for application in children during infectious diarrhea.

Increased small intestinal permeability in ulcerative colitis: rather genetic than environmental and a risk factor for extensive disease?

BACKGROUND

A disturbed epithelial barrier could play a pivotal role in ulcerative colitis (UC). We performed a family-based study analyzing in vivo gastrointestinal permeability in patients with UC, their healthy relatives, spouses, and controls.

METHODS

In total, 89 patients with UC in remission, 35 first-degree relatives (UC-R), 24 nonrelated spouses (UC-NR), and 99 healthy controls (HC) were studied. Permeability was assessed by a sugar-drink test using sucrose (gastroduodenal permeability), lactulose/mannitol (intestinal permeability), and sucralose (colonic permeability). Data were correlated with clinical characteristics including medical treatment.

RESULTS

Increased intestinal permeability was detected significantly more often in UC patients in remission (25/89, 28.1%) compared with HC (6/99, 6.1%; P < 0.001). Similar results were obtained in UC-R (7/35, 20.0%; P = 0.01 compared with HC) regardless of sharing the same household with the patients or not. No difference was found between UC-NR (3/24, 12.5%) and HC. Notably, in UC patients increased intestinal permeability was found in 12/28 patients (42.9%) with pancolitis, 7/30 (23.3%) patients with left-sided colitis, and in 2/19 (10.5%) patients with proctitis (P = 0.04). Gastroduodenal and colonic permeability were similar in all groups. Among patients on azathioprine, increased intestinal permeability was only seen in 1/18 (5.6%) patients. In contrast, in 24/70 (34.3%) patients without azathioprine, an increased intestinal permeability was found (P = 0.005).

CONCLUSIONS

An increased intestinal but not colonic permeability was found in UC patients in clinical remission that could mark a new risk factor for extensive disease location. Similar findings in healthy relatives but not spouses suggest that this barrier defect is genetically determined.

Fecal calprotectin in predicting relapse of inflammatory bowel diseases: a meta-analysis of prospective studies

BACKGROUND

Fecal calprotectin (FC) is a relatively new marker of intestinal inflammation. Recently, many studies have extended its role in predicting relapse of quiescent inflammatory bowel disease (IBD), but the reported results have been inconsistent. We aimed to perform a meta-analysis of the predictive capacity of FC in IBD relapse.

METHODS

We systematically searched the Medline, Web of Science, Cochrane Library, and EMBASE databases for prospective studies that used FC concentrations at remission in predicting relapse of Crohn's disease (CD) and ulcerative colitis (UC). Pooled sensitivity, specificity, and other diagnostic indices were evaluated.

RESULTS

A total of 672 IBD patients (318 UC and 354 CD) from six different studies were analyzed. The pooled sensitivity and specificity of FC to predict relapse of quiescent IBD was 78% (95% confidence interval [CI]: 72-83) and 73% (95% CI: 68-77), respectively. The area under the summary receiver-operating characteristic (sROC) curve was 0.83 and the diagnostic odds ratio was 10.31 (95% CI: 5.05-21.06). The capacity of FC to predict relapse was comparable between UC and CD. In CD patients the predictive value of FC in isolated small bowel CD was not assessed due to insufficiency of available data. Compared with all enrolled CD patients, FC appeared to be more accurate in ileocolonic and colonic CD.

CONCLUSIONS

As a simple and noninvasive marker, FC is useful to predict relapse in quiescent IBD patients.

Rapid test for fecal calprotectin levels in children with Crohn disease

Assessment of fecal calprotectin, a surrogate marker of mucosal inflammation, is a promising means to monitor therapeutic response in pediatric inflammatory bowel disease, especially if the result is readily available. We tested the performance of a novel calprotectin rapid test, Quantum Blue, versus the conventional enzyme-linked immunosorbent assay in 134 stool samples from 56 pediatric patients with Crohn disease. The intraclass correlation coefficient analysis reflected good agreement (intraclass correlation coefficient 0.97 [95% confidence interval 0.95-0.98]) but agreement was better in lower values, where dilutions were not required. Using a cutoff of 100 μg/g for normal values, the percentage agreement between the 2 tests was 87%. The optimal cutoff values to guide clinical decisions in the therapy of inflammatory bowel disease have yet to be determined.

Management of pediatric ulcerative colitis: joint ECCO and ESPGHAN evidence-based consensus guidelines

BACKGROUND AND AIMS

Pediatric ulcerative colitis (UC) shares many features with adult-onset disease but there are some unique considerations; therefore, therapeutic approaches have to be adapted to these particular needs. We aimed to formulate guidelines for managing UC in children based on a systematic review (SR) of the literature and a robust consensus process. The present article is a product of a joint effort of the European Crohn's and Colitis Organization (ECCO) and the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN).

METHODS

A group of 27 experts in pediatric IBD participated in an iterative consensus process including 2 face-to-face meetings, following an open call to ESPGHAN and ECCO members. A list of 23 predefined questions were addressed by working subgroups based on a SR of the literature.

RESULTS

A total of 40 formal recommendations and 68 practice points were endorsed with a consensus rate of at least 89% regarding initial evaluation, how to monitor disease activity, the role of endoscopic evaluation, medical and surgical therapy, timing and choice of each medication, the role of combined therapy, and when to stop medications. A management flowchart, based on the Pediatric Ulcerative Colitis Activity Index (PUCAI), is presented.

CONCLUSIONS

These guidelines provide clinically useful points to guide the management of UC in children. Taken together, the recommendations offer a standardized protocol that allows effective, timely management and monitoring of the disease course, while acknowledging that each patient is unique.

Fecal calprotectin levels are higher in rural than in urban Chinese infants and negatively associated with growth

BACKGROUND

Fecal calprotectin (FC) is an established simple biomarker of gut inflammation. To examine a possible relationship between linear growth and gut inflammation, we compared fecal calprotectin levels in 6 month old infants from poor rural vs affluent urban families.

METHODS

The project was a cross-sectional comparison of FC from rural and urban populations in China. The relationship between length-for-age Z-score (LAZ) and FC concentrations were also compared. Single fecal samples were assayed for FC using EK-CAL ELISA kits.

RESULTS

The age of subjects for both locations was 6.1 ± 0.2 mo; all were apparently healthy. The mean ± SD of the LAZ for the rural and urban infants were -0.6 ± 0.9 and 0.4 ± 0.9, respectively. FC had a non-normal distribution. The median FC of 420.9 and 140.1 μg/g for rural and urban infants, respectively, were significantly different (P < 0.0001). For the rural group, linear regression analysis showed that an increase in FC of 100 μg/g was associated with a decrease of 0.06 in LAZ.

CONCLUSION

FC levels were significantly elevated in the rural infants and high concentrations accounted for approximately one-third of the low LAZ scores of these infants.

Vedolizumab for the treatment of active ulcerative colitis: a randomized controlled phase 2 dose-ranging study

BACKGROUND

Vedolizumab is a gut-selective biologic that has shown efficacy in ulcerative colitis (UC) and Crohn's disease (CD). We studied the pharmacokinetics, pharmacodynamics, safety, tolerability, and efficacy of a new formulation of vedolizumab produced by an improved manufacturing process.

METHODS

UC patients were randomized to receive vedolizumab (2, 6, or 10 mg/kg) or placebo on days 1, 15, 29, and 85. Safety, pharmacokinetics, pharmacodynamics, and immunogenicity evaluations were performed at multiple timepoints through day 253. Partial Mayo Scores and fecal calprotectin levels were used to assess efficacy.

RESULTS

In all, 46 patients (9 placebo, 37 vedolizumab) received at least one dose of study medication. The vedolizumab serum concentration declined monoexponentially until concentrations reached 1-10 μg/mL, and then fell nonlinearly. Vedolizumab maximum serum concentration (C(max) ) and area under the curve (AUC) increased approximately proportionally as a function of dose. Vedolizumab maximally saturated α(4) β(7) receptors on peripheral serum lymphocytes at all measurable serum concentrations. Vedolizumab was well tolerated, with no deaths and no adverse events leading to discontinuation. At every assessment from day 29 through day 253, over 50% of vedolizumab-treated patients were in clinical response, while placebo response rates generally ranged between 22% and 33%. Vedolizumab treatment reduced fecal calprotectin levels compared with placebo.

CONCLUSIONS

Vedolizumab demonstrated dose-proportional pharmacokinetics and maximally saturated α(4) β(7) receptors over the tested dose range. Multiple dosing up to 10 mg/kg was well tolerated. Over the course of follow-up a greater proportion of patients treated with vedolizumab were in clinical response than those who were assigned to placebo.

Limitations of fecal calprotectin at diagnosis in untreated pediatric Crohn's disease

BACKGROUND

Fecal Calprotectin (FC) is a validated screening test for intestinal inflammation in Crohn's disease (CD). The objective of the study was to prospectively evaluate the limitations of FC for identifying CD in newly diagnosed untreated pediatric patients and to assess the association of FC levels with disease location and serum inflammatory markers.

METHODS

Consecutive children with new onset untreated CD participating in the ongoing ESPGHAN GROWTH CD study were evaluated at diagnosis for disease activity, extent, C-reactive protein (CRP), and FC.

RESULTS

In all, 60 children met the inclusion criteria (mean age 12.6 ± 4.6 years,), 25 (42%) with mild disease, 17 (28%) moderate disease, and 18 (30%) severe disease. Twenty-seven (45%) had small bowel disease only. Median FC levels did not differ between children with small bowel only (2198 μg/g interquartile range [IQR] 696-2400) and those with colonic involvement (with or without small bowel disease; 2400 μg/g (IQR 475-2400) (P = 0.76). FC was elevated in 95% of patients, in comparison to CRP (86%) and erythrocyte sedimentation rate (ESR) (83%). Three children (5%) who had normal calprotectin levels also had low or normal CRP and/or ESR. There was no correlation between calprotectin levels and either the pediatric CD activity index (r = -0.11; P = 0.94) or physicians global assessment.

CONCLUSIONS

FC levels in active disease confined to the small bowel were elevated in the vast majority of children and site of disease was not a confounding factor in this setting. Patients with low FC had a trend toward low levels of inflammatory markers as well. We did not find a significant correlation between FC and clinical indices of activity.

Fecal calprotectin and S100A12 have low utility in prediction of small bowel Crohn's disease detected by wireless capsule endoscopy

OBJECTIVE

Data on fecal calprotectin and S100A12 in predicting wireless capsule endoscopy (WCE) findings in suspicion of Crohn's disease (CD) are scarce. Our aim was to study the role of calprotectin and S100A12 in predicting inflammatory lesions of small bowel in patients undergoing WCE.

MATERIAL AND METHODS

84 patients undergoing WCE (77 for suspicion of CD and 7 CD patients for evaluation of disease extent) were prospectively recruited. WCE findings were scored. Patients provided a stool sample for measurements of biomarkers. Patients underwent an esophagogastroduodenoscopy and ileocolonoscopy before WCE.

RESULTS

WCE was abnormal in 35 (42%) of 84 patients: 14 patients with CD, 8 with NSAID enteropathies, 8 with angioectasias, 4 with polyps or tumors, and 1 with ischemic stricture. Median calprotectin concentration in the study population was 22 μg/g (range 2-342) and S100A12 concentration 0.048 μg/g (range 0.003-1.215). Fecal calprotectin was significantly higher in CD patients (median 91, range 2-312) compared with those with normal WCE or other abnormalities (p = 0.008), whereas fecal S100A12 (0.087 μg/g, range 0.008-0.896) did not differ between the groups (p = 0.166). In detecting inflammatory small bowel lesions, sensitivity, specificity, positive predictive value, and negative predictive value for fecal calprotectin (cutoff 50 μg/g) were 59%, 71%, 42%, and 83%, and for S100A12 (cutoff 0.06 μg/g) these were 59%, 66%, 38%, and 82%.

CONCLUSIONS

In predicting small bowel inflammatory changes, fecal biomarkers calprotectin and S100A12 have moderate specificity, but low sensitivity. Neither fecal calprotectin nor S100A12 can be used for screening or excluding small bowel CD.

Faecal calprotectin in HIV-infected, HAART-naïve Ugandan children

OBJECTIVES

Calprotectin is a calcium- and zinc-binding protein and a marker in faeces of gastrointestinal inflammation. Reference values have been established in children older than 4 years. The aim of the present study was to determine the concentration of faecal calprotectin (FC) in human immunodeficiency virus (HIV)-infected, highly active antiretroviral therapy-naïve Ugandan children and compare it with the reference value.

METHODS

We tested 193 HIV-infected children ages 0 to 12 years in a hospital-based survey for FC. A standardised interview with sociodemographic information and medical history was used to assess risk factors. A cluster of differentiation 4 (CD4) cell percentage was prevalent in all of the children.

RESULTS

The median FC concentrations decreased with increasing age, as in healthy children. The median concentration was 208 mg/kg in infants 0 to 1 year, 171 mg/kg among toddlers 1 to 4 years, and 62 mg/kg for children 4 to 12 years. Children with advanced disease and a low CD4 cell percentage had significantly higher FC concentrations than those with a high CD4 cell percentage. Children older than 4 years with diarrhoea had significantly higher FC concentrations compared with those without diarrhoea.

CONCLUSIONS

HIV-infected children older than 4 years had a median FC concentration above the reference value, and gut inflammation in the children with elevated values is likely. Children with more advanced disease had increased FC concentrations regardless of age.

Fast and sharp decrease in calprotectin predicts remission by infliximab in anti-TNF naïve patients with ulcerative colitis

AIM

To evaluate the effect of infliximab induction therapy on calprotectin levels in patients with ulcerative colitis (UC).

PATIENTS AND METHODS

In this prospective study 53 patients with active UC from 17 centers were treated with infliximab therapy (5 mg/kg) at baseline, week 2, and week 6. Faecal calprotectin was measured every week. Sigmoidoscopies were performed at baseline, week 6 and week 10.

RESULTS

Median calprotectin levels decreased from 1260 (IQR 278.5- 3418) at baseline to 72.5 (IQR 18.5 - 463) at week 10 (p<0.001). After 10 weeks, infliximab therapy induced endoscopic remission and a decrease in calprotectin to<50 mg/kg or at least a 80% decrease from baseline level in 58% of patients. A significant and steep decrease of calprotectin levels was seen at week 2 for patients with an endoscopic remission at week 10 as compared to patients who did not show a remission. (p<0.001). At week 10 an excellent correlation was found between endoscopic remission and clinical Mayo score reflected by an AUC of ROC analyses of 0.94 (0.87-1) and with calprotectin measurements (AUC 0.91 (0.81-1)) : all patients with calprotectin levels <50 mg/kg, and a normal clinical Mayo score (=0) were in endoscopic remission.

CONCLUSIONS

Infliximab induces a fast and significant decrease of faecal calprotectin levels in anti-TNF naïve patients with ulcerative colitis predictive for remission of disease.

Usefulness of faecal calprotectin measurement in children with various types of inflammatory bowel disease

Introduction. The aim of the study was to assess the usefulness of the FC measurement in children with various types of IBD and relation to the disease activity. Patients and Methods. 91 patients (49 boys: 53.85% and 42 girls: 46.15%, mean age: 13.38 years, range 6–18 years) were included in the analysis. Patients were divided into the groups: B1—24 children with CD, B2—16 patients with UC, and a group comprising 31 children with other types of colitis; the control group (K) comprised 20 healthy children. FC was assayed by ELISA method, using Phical test (Calpro). Results. The mean faecal calprotectin concentrations were higher in children with CD and UC as compared to healthy controls, patients with eosinophilic, lymphocytic, and nonspecific colitis. A positive correlation was observed between FC concentrations and the disease activity (the PCDAI scale, the Truelove-Witts Scale, and the endoscopic Rachmilewitz Index). Conclusion. It seems that the FC concentrations can be a useful, safe, and noninvasive test in children suspected for IBD, since FC concentration is higher in children with CD and UC than in patients with other inflammatory diseases.

Biomarkers in inflammatory bowel disease: current practices and recent advances

Crohn's disease and ulcerative colitis represent the two main forms of the idiopathic chronic inflammatory bowel diseases (IBD). Currently available blood and stool based biomarkers provide reproducible, quantitative tools that can complement clinical assessment to aid clinicians in IBD diagnosis and management. C-reactive protein and fecal based leukocyte markers can help the clinician distinguish IBD from noninflammatory diarrhea and assess disease activity. The ability to differentiate between forms of IBD and predict risk for disease complications is specific to serologic tests including antibodies against Saccharomyces cerevisiae and perinuclear antineutrophil cytoplasmic proteins. Advances in genomic, proteomic, and metabolomic array based technologies are facilitating the development of new biomarkers for IBD. The discovery of novel biomarkers, which can correlate with mucosal healing or predict long-term disease course has the potential to significantly improve patient care. This article reviews the uses and limitations of currently available biomarkers and highlights recent advances in IBD biomarker discovery.

Validation of a point-of-care desk top device to quantitate fecal calprotectin and distinguish inflammatory bowel disease from irritable bowel syndrome

BACKGROUND AND AIMS

The neutrophil protein calprotectin has been investigated as a surrogate marker for intestinal inflammation. This study was designed to contrast fecal calprotectin levels in patients with inflammatory and non-inflammatory intestinal diseases and to compare the results obtained from the standard ELISA-based method with those obtained from a novel desk-top device.

METHODS

Soluble proteins were extracted from stool samples of 50 participating patients, including those diagnosed with Ulcerative Colitis, Crohn's Disease or IBS, and volunteers with no known intestinal problems. Calprotectin was assessed in the extracted material using the "desk top" Bühlmann Quantum Blue Reader® or by standard ELISA techniques.

RESULTS

The mean concentration of calprotectin in the IBD patients group was significantly higher than the mean concentration found in IBS patients and healthy controls (p=0.01). Calprotectin concentrations in IBS patients and controls were indistinguishable. IBD patients that had undergone recent surgery displayed scores similar to controls and IBS patients. Excluding these patients yielded a specificity of 100% for results from both CD and UC patients and an accuracy rate of 1 for CD and 0.89 for UC patients in ROC analysis. Quantum Blue Reader® calprotectin levels were available within 30 min and correlated well with results derived from standard ELISA assays, which took over 8h to complete.

CONCLUSION

Our results confirm the effective use of fecal calprotectin levels in differentiating non-inflammatory from active inflammatory intestinal diseases. The desk top Bühlmann Quantum Blue Reader® exhibits a fast, non-invasive, and reliable way of identifying an inflammatory intestinal disease.

Crohn's disease patients have more IgG-binding fecal bacteria than controls

In Crohn's disease (CD), chronic gut inflammation leads to loss of mucosal barrier integrity. Subsequent leakage of IgG to the gut could produce an increase of IgG coating of intestinal bacteria. We investigated if there is more IgG coating in patients than in volunteers and whether this is dependent on the host IgG response or on the gut bacteria. Fecal and serum samples were obtained from 23 CD patients and 11 healthy volunteers. Both the in vivo IgG-coated fecal bacteria and in vitro IgG coating after serum addition were measured by flow cytometry and related to disease activity. The bacterial composition in feces was determined using fluorescence in situ hybridization. The IgG-binding capacities of Escherichia coli strains isolated from feces of patients and volunteers were assessed. The results showed that the in vivo IgG-coated fraction of fecal bacteria of patients was slightly larger than that of volunteers but significantly larger after incubation with either autologous or heterologous serum. This was dependent on the bacteria and independent of disease activity or the serum used. The presence of more Enterobacteriaceae and fewer faecalibacteria in patient feces was confirmed. E. coli isolates from patients bound more IgG than isolates from volunteers (P < 0.05) after the addition of autologous serum. Together, these results indicate that CD patients have more IgG-binding gut bacteria than healthy volunteers. We showed that the level of IgG coating depends on the bacteria and not on the serum used. Furthermore, CD patients have a strong specific immune response to their own E. coli bacteria.

Infliximab in pediatric inflammatory bowel disease rapidly decreases fecal calprotectin levels

AIM: To study the response to infliximab in pediatric inflammatory bowel disease (IBD), as reflected in fecal calprotectin levels.

METHODS: Thirty-six pediatric patients with IBD [23 Crohn’s disease (CD), 13 ulcerative colitis (UC); median age 14 years] were treated with infliximab. Fecal calprotectin was measured at baseline, and 2 and 6 wk after therapy, and compared to blood inflammatory markers. Maintenance medication was unaltered until the third infusion but glucocorticoids were tapered off if the patient was doing well.

RESULTS: At introduction of infliximab, median fecal calprotectin level was 1150 μg/g (range 54-6032 μg/g). By week 2, the fecal calprotectin level had declined to a median 261 μg/g (P < 0.001). In 37% of the patients, fecal calprotectin was normal (< 100 μg/g) at 2 wk. By week 6, there was no additional improvement in the fecal calprotectin level (median 345 μg/g). In 22% of the patients, fecal calprotectin levels increased by week 6 to pretreatment levels or above, suggesting no response (or a loss of early response). Thus, in CD, the proportion of non-responsive patients by week 6 seemed lower, because only 9% showed no improvement in their fecal calprotectin level when compared to the respective figure of 46% of the UC patients (P < 0.05).

CONCLUSION: When treated with infliximab, fecal calprotectin levels reflecting intestinal inflammation normalized rapidly in one third of pediatric patients suggesting complete mucosal healing.

Ruling out IBD: estimation of the possible economic effects of pre-endoscopic screening with F-calprotectin

OBJECTIVES

To estimate the possible economic effects of a sequential testing strategy with F-calprotectin to minimize colonoscopies.

DESIGN AND METHODS

Retrospective study in a third party payer perspective. The costs were calculated from initial F-calprotectin test results of 3639 patients. Two cut-off levels were used: 50 μg/g feces and 100 μg/g feces, respectively. The cost-effectiveness of the testing strategy was estimated through the short-term cost avoidance and reduction in demand for colonoscopies.

RESULTS

The estimated demand for colonoscopies was reduced by 50% with the 50 μg/g cut-off and 67% with the 100 μg/g cut-off. This corresponded to a cost avoidance of approximately €1.57 million and €2.13 million, respectively.

CONCLUSIONS

The use of F-calprotectin as a screening test substantially could reduce the number of invasive measurements necessary in the diagnostic work-up of patients with suspected IBD, as well as the associated costs.

First phase 1 double-blind, placebo-controlled, randomized rectal microbicide trial using UC781 gel with a novel index of ex vivo efficacy

OBJECTIVES

Successful control of the HIV/AIDS pandemic requires reduction of HIV-1 transmission at sexually-exposed mucosae. No prevention studies of the higher-risk rectal compartment exist. We report the first-in-field Phase 1 trial of a rectally-applied, vaginally-formulated microbicide gel with the RT-inhibitor UC781 measuring clinical and mucosal safety, acceptability and plasma drug levels. A first-in-Phase 1 assessment of preliminary pharmacodynamics was included by measuring changes in ex vivo HIV-1 suppression in rectal biopsy tissue after exposure to product in vivo.

METHODS

HIV-1 seronegative, sexually-abstinent men and women (N = 36) were randomized in a double-blind, placebo-controlled trial comparing UC781 gel at two concentrations (0.1%, 0.25%) with placebo gel (1∶1∶1). Baseline, single-dose exposure and a separate, 7-day at-home dosing were assessed. Safety and acceptability were primary endpoints. Changes in colorectal mucosal markers and UC781 plasma drug levels were secondary endpoints; ex vivo biopsy infectibility was an ancillary endpoint.

RESULTS

All 36 subjects enrolled completed the 7-14 week trial (100% retention) including 3 flexible sigmoidoscopies, each with 28 biopsies (14 at 10 cm; 14 at 30 cm). There were 81 Grade 1 adverse events (AEs) and 8 Grade 2; no Grade 3, 4 or procedure-related AEs were reported. Acceptability was high, including likelihood of future use. No changes in mucosal immunoinflammatory markers were identified. Plasma levels of UC781 were not detected. Ex vivo infection of biopsies using two titers of HIV-1(BaL) showed marked suppression of p24 in tissues exposed in vivo to 0.25% UC781; strong trends of suppression were seen with the lower 0.1% UC781 concentration.

CONCLUSIONS

Single and 7-day topical rectal exposure to both concentrations of UC781 were safe with no significant AEs, high acceptability, no detected plasma drug levels and no significant mucosal changes. Ex vivo biopsy infections demonstrated marked suppression of HIV infectibility, identifying a potential early biomarker of efficacy. (Registered at ClinicalTrials.gov; #NCT00408538).

Fecal eosinophil cationic protein as a marker of active disease and treatment outcome in collagenous colitis: a pilot study

BACKGROUND AND AIMS

Fecal calprotectin (FC) is used as a marker for intestinal inflammation in inflammatory bowel disease (IBD) but there is no reliable marker for collagenous colitis (CC). We have previously demonstrated that the mucosal inflammation in CC is characterized by eosinophil activation, which is restored during budesonide treatment, but there is no enhanced neutrophil activity. The aim of this study was to evaluate the use of fecal eosinophil cationic protein (F-ECP) and eosinophil protein X (F-EPX) compared with the neutrophil-derived myeloperoxidase (F-MPO) and FC in patients treated for active CC.

METHODS

Patients with active CC (n = 12) were studied before and after 3, 7, 28 and 56 days of budesonide treatment. Clinical symptoms and stool frequency were recorded, fecal samples were collected, and F-ECP, F-EPX, F-MPO and FC were measured at each occasion.

RESULTS

All but one patient achieved remission. On inclusion 92%, 67%, 67% and 75% of the patients had elevated F-ECP, F-EPX, F-MPO and FC levels, respectively. All markers decreased during the treatment, particularly F-ECP and F-EPX, which decreased after only 3 days. At the end of the study 100%, 92%, 83% and 75% of the patients had normal F-ECP, F-EPX, F-MPO and FC values, respectively.

CONCLUSION

F-ECP demonstrated the best discriminating capacity in detecting active CC. A normalized F-ECP and F-EPX may further be studied as a marker for successful treatment. During budesonide treatment there is a rapid fall in F-ECP and F-EPX, accompanied by clinical improvement, indicating an essential role for the eosinophil participating in the pathophysiology of CC.

The utility of biomarkers in the diagnosis and therapy of inflammatory bowel disease

Fecal and serologic biomarkers can be used in the diagnosis and management of inflammatory bowel disease (IBD). Fecal markers such as calprotectin and lactoferrin have been studied for their ability to identify patients with IBD, assess disease activity, and predict relapse. Antibodies against Saccharomyces cerevisiae and perinuclear antineutrophil cytoplasmic proteins have been used in diagnosis of IBD, to distinguish Crohn's disease (CD) from ulcerative colitis, and to predict the risk of complications of CD. Tests for C-reactive protein and erythrocyte sedimentation rate have been used to assess inflammatory processes and predict the course of IBD progression. Levels of drug metabolites and antibodies against therapeutic agents might be measured to determine why patients do not respond to therapy and to select alternative treatments. This review addresses the potential for biomarker assays to improve treatment strategies and challenges to their use and development.

Laboratory tests for the diagnosis and management of chronic canine and feline enteropathies

Chronic enteropathies are commonly encountered in both cats and dogs. Although definitive diagnosis often requires collection of gastrointestinal biopsies for histopathologic evaluation, less invasive laboratory tests can be highly informative and should be performed prior to biopsy collection. Tests for determination of infectious causes comprise those for helminthic, protozoal, bacterial, or fungal organisms. Intestinal function and disease may be assessed by measuring serum concentrations of cobalamin, folate, and C-reactive protein, and fecal concentrations of α(1)-proteinase inhibitor. Ongoing research has led to development of tests for serum perinuclear antineutrophilic cytoplasmic antibodies, and fecal inflammatory markers, including S100-proteins and N-methylhistamine.

Faecal calprotectin concentrations in apparently healthy children aged 0-12 years in urban Kampala, Uganda: a community-based survey

Background

Calprotectin is a calcium and zinc binding protein, abundant in neutrophils and is extremely stable in faeces. Faecal calprotectin is used as a non-specific marker for gastrointestinal inflammation. It has a good diagnostic precision to distinguish between irritable bowel syndrome and inflammatory bowel disease. Studies have established normal concentrations in healthy children; all these studies have been performed in high-income countries. The objective of this study was to determine the concentration of faecal calprotectin in apparently healthy children aged 0-12 years in urban Kampala, Uganda.

Method

We tested 302 apparently healthy children aged, age 0-12 years (162 female, 140 male) in urban Kampala, Uganda. The children were recruited consecutively by door-to-door visits. Faecal calprotectin was analyzed using a quantitative enzyme-linked immunosorbent assay. Faeces were also tested for Helicobacter pylori (H. pylori) antigen, for growth of enteropathogens and microscopy was performed to assess protozoa and helminths. A short standardized interview with socio-demographic information and medical history was obtained to assess health status of the children.

Results

In the different age groups the median faecal calprotectin concentrations were 249 mg/kg in 0 < 1 year (n = 54), 75 mg/kg in 1 < 4 years (n = 89) and 28 mg/kg in 4 < 12 years (n = 159). There was no significant difference in faecal calprotectin concentrations and education of female caretaker, wealth index, gender, habits of using mosquito nets, being colonized with H. pylori or having other pathogens in the stool.

Conclusion

Concentrations of faecal calprotectin among healthy children, living in urban Ugandan, a low-income country, are comparable to those in healthy children living in high-income countries. In children older than 4 years, the faecal calprotectin concentration is low. In healthy infants faecal calprotectin is high. The suggested cut-off concentrations in the literature can be used in apparently healthy Ugandan children. This finding also shows that healthy children living under poor circumstances do not have a constant inflammation in the gut. We see an opportunity to use this relatively inexpensive test for further understanding and investigations of gut inflammation in children living in low-income countries.