Combined use of noninvasive tests is useful in the initial diagnostic approach to a child with suspected inflammatory bowel disease

Role of Intestinal Ultrasound for IBD Care: A Practical Approach

Intestinal ultrasound (IUS) has recently become the imaging technique of choice for patients with different types of intestinal inflammation. IUS has a high sensitivity, specificity, positive predictive value, and negative predictive value when diagnosing Crohn's disease or ulcerative colitis. Further, it is now the preferred imaging modality for routine IBD reevaluations because of its non-invasiveness, cost-effectiveness, availability (at least in Europe), and reproducibility in all age groups. However, the clinical success of IUS requires IUS training for doctors and technicians who perform IUS with a standardised description of ultrasound findings of the terminal ileum and entire colon. Complications such as abscess formation, fistulae, and stenosis can be detected by either conventional IUS or contrast-enhanced ultrasound (CEUS). Lately, several disease activity scores have been proposed for Crohn's disease, postoperative Crohn's disease, and ulcerative colitis both in adults (including elderly) and in children. IUS was successfully used in randomised clinical trials in order to measure the treatment response. Therefore, IUS now plays a central role in clinical decision making.

Ultrasound in Pediatric Inflammatory Bowel Disease-A Review of the State of the Art and Future Perspectives

Inflammatory bowel disease (IBD) comprises a group of relapsing, chronic diseases of the gastrointestinal tract that, in addition to adults, can affect children and adolescents. To detect relapses of inflammation, these patients require close observation, frequent follow-up, and therapeutic adjustments. While reference standard diagnostics include anamnestic factors, laboratory and stool sample assessment, performing specific imaging in children and adolescents is much more challenging than in adults. Endoscopic and classic cross-sectional imaging modalities may be invasive and often require sedation for younger patients. For this reason, intestinal ultrasound (IUS) is becoming increasingly important for the non-invasive assessment of the intestine and its inflammatory affection. In this review, we would like to shed light on the current state of the art and provide an outlook on developments in this field that could potentially spare these patients more invasive follow-up procedures.

Relevance of sonographic parameters for inflammatory bowel disease in children

PURPOSE

Intestinal ultrasound (IUS) is widely used as the first exam in patients with suspected inflammatory bowel disease (IBD). This study investigated the accuracy of several IUS parameters, including increased bowel wall thickening (BWT), in detecting IBD in a paediatric population.

METHODS

The study included an unselected series of 113 patients aged 2-18 years (mean age 10.8 years, 65 male), referred for recurrent abdominal pain or altered bowel habits, without known organic diseases, to perform an IUS as first investigation of a diagnostic workup. Patients with full systematic IUS examination, clinical and biochemical exams, and ileocolonoscopy or an uneventful follow-up at least one year follow up were eligible.

RESULTS

23 IBD patients (20.4%; 8 ulcerative colitis, 12 Crohn's disease and 3 indeterminate colitis) were diagnosed. We found that increased BWT > 3 mm (OR 5.4), altered IUS bowel pattern (IUS-BP, OR 9.8) and mesenteric hypertrophy (MH, OR 5.2) accurately identified IBD at the multivariate analysis. IUS-BP, MH and BWT > 3 mm had a sensitivity of 78.3%, 65.2% and 69.6% and a specificity of 93.3%, 92.2% and 96.7%, respectively. The combination of these three alterations increased the specificity up to 100%, whilst decreased sensitivity to 56.5%.

CONCLUSION

Among several US parameters suggestive of IBD, the increased BWT, MH and altered echopattern are independent predictors of IBD. The ultrasonographic diagnosis of IBD could be more accurate if relied on combination of different sonographic parameters, than on the sole BWT evaluation.

The Role of Ultrasound in Chronic Intestinal Diseases in Pediatric Patients

Chronic inflammatory bowel diseases (IBD) are chronic disorders of the gastrointestinal tract, with an increasing incidence in pediatric populations. Ultrasound of the intestinal wall represents the first-line imaging technique in children since it is a noninvasive method, is free of ionizing radiation, and is inexpensive. Furthermore, the absence of intestinal wall thickening has a good negative predictive value for IBD, which is greater for Crohn's disease than for ulcerative colitis. Ultrasound is used for the diagnosis of disease, for the differential diagnosis in IBD, in the follow-up of known IBD, in the definition of the site and extent of the disease, for the diagnosis of intestinal complications, for the evaluation of disease activity, in the definition of prognostic parameters, and in the post-operative follow-up.

Non-IgE- or Mixed IgE/Non-IgE-Mediated Gastrointestinal Food Allergies in the First Years of Life: Old and New Tools for Diagnosis

non-IgE and mixed gastrointestinal food allergies present various specific, well-characterized clinical pictures such as food protein-induced allergic proctocolitis, food protein-induced enterocolitis and food protein-induced enteropathy syndrome as well as eosinophilic gastrointestinal disorders such as eosinophilic esophagitis, allergic eosinophilic gastroenteritis and eosinophilic colitis. The aim of this article is to provide an updated review of their different clinical presentations, to suggest a correct approach to their diagnosis and to discuss the usefulness of both old and new diagnostic tools, including fecal biomarkers, atopy patch tests, endoscopy, specific IgG and IgG4 testing, allergen-specific lymphocyte stimulation test (ALST) and clinical score (CoMiss).

Fecal calprotectin in children with familial Mediterranean fever in the attack-free period

BACKGROUND

Familial Mediterranean fever (FMF) is an autosomal recessive disease characterized by recurrent episodes of fever and serosal inflammation. The aim of this study was to evaluate fecal calprotectin (FC) in children with FMF during the non-attack period.

METHODS

A retrospective evaluation was made of the data of a total 66 patients diagnosed with FMF in an attack-free period and without amyloidosis or inflammatory bowel disease (IBD). FC level in the FMF patients was compared with that in the patients with IBD and healthy control subjects.

RESULTS

The FMF patients consisted of 37 boys (56.1%) with a mean age of 10.1 ± 3.9 years. Mean FC was 192.5 μg/g (range, 19.5-800 μg/g) in the FMF group, 597.9 μg/g (range, 180-800 μg/g) in the IBD group, and 43.8 μg/g (range, 19.5-144 μg/g) in the control group. The FC level in the children with FMF was higher than in the control group (P < 0.001), and the FC level of the IBD patients was higher than both the FMF and the control groups (P = 0.020, P < 0.001, respectively).

CONCLUSIONS

FC was higher in FMF patients compared with healthy children even in the absence of IBD/amyloidosis. Even though colonoscopy is the gold standard in identifying intestinal inflammation in FMF patients, FC, a non-invasive and inexpensive method, can be used for screening. The presence of subclinical intestinal inflammation was also quantitatively identified in children with FMF.

Noninvasive testing in the management of children with suspected inflammatory bowel disease

Objective: To assess the accuracy of noninvasive parameters, fecal calprotectin (FC), increased bowel wall thickening (BWT) at intestinal ultrasound (IUS) and blood inflammatory indexes (BII), alone or in combination, as diagnostic tools for inflammatory bowel disease (IBD) in pediatric patients. Methods: Retrospective data were collected on consecutive children (age 2-18 years) referred to our pediatric gastroenterology clinic, for recurrent abdominal pain and/or altered bowel habit from 2007 to 2013. Subjects who had diagnostic workup: laboratory tests (FC, BII, white blood cell (WBC), C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR)) and IUS as initial assessment were eligible. Subjects with known gastrointestinal (GI) diseases, or signs or symptoms highly suggestive for organic diseases necessitating prompt endoscopy (e.g., perianal disease or rectal bleeding), or who had recently performed endoscopy were excluded. The accuracy of noninvasive tests for detecting IBD was assessed using endoscopic and/or radiological investigations, performed in subsequent clinical follow up, as reference gold standard. Results: Seventy-seven patients (mean age 11.3, 44 males) were included, 23 (29.9%) with a final diagnosis of IBD. As single tests, FC gave the highest sensitivity (96%) but lower specificity (72%) and IUS highest specificity (96%) with lower sensitivity (70%). The combination of FC + IUS showed excellent accuracy for detecting children with IBD with positive predictive value: 100%; negative predictive value: 88.5%. The probability of IBD in children with normal FC, BII and IUS was 0.09%. Conclusions: FC and increased BWT at IUS are accurate to guide reassurance or proceeding with further invasive procedures for detecting IBD in children with mild GI symptoms.

Ultrasonographic study of intestinal Doppler blood flow in infantile non-IgE-mediated gastrointestinal food allergy

BACKGROUND

Although non-IgE-mediated gastrointestinal food allergy has increased rapidly in Japan, a small number of reports has evaluated B-mode and Doppler ultrasonographic findings in the acute phase of infantile gastrointestinal milk allergy. The aim of the present study was to compare the diagnostic utility of ultrasonographic findings and laboratory allergic data in non-IgE-mediated infantile gastrointestinal milk allergy.

METHODS

Sixteen cases of active non-IgE-mediated infantile gastrointestinal milk allergy, diagnosed by food elimination tests and oral food challenge tests (OFCTs) (group A), 15 cases of acute viral gastroenteritis (AGE) (group B), and 15 controls (group C) were enrolled. 1) B-mode abdominal ultrasound findings, 2) laboratory allergic data including eosinophil counts (Eos), serum IgE, and the antigen-specific lymphocyte proliferation test (ALPT) against milk protein, and 3) vessel density (VD) indirectly quantified by gastrointestinal Doppler flow at jejunum, ileum, and sigmoid colonic mucosae were evaluated and compared among the groups.

RESULTS

In the small intestine, wall thickening, dilation, mesenteric thickening, and poor peristalsis were found in 100%, 62.5%, 93.7%, and 100%, respectively, in group A. Eos, IgE, ALPT, and VD were positive in 25.0%, 0%, 87.5%, and 100%, respectively, in group A. Small intestinal VD was significantly greater in group A than in groups B (jejunum p < .001; ileum p < .001) and C (jejunum p < .001; ileum p < .001), with no significant differences between groups B and C (jejunum: p = .74; ileum: p = .73).

CONCLUSIONS

Abdominal Doppler ultrasonography and small intestinal VD at symptomatic state can support the diagnosis and evaluation of non-IgE-mediated infantile gastrointestinal milk allergy with symptoms of vomiting, diarrhea, and failure to thrive.

Fecal Calprotectin to Detect Inflammatory Bowel Disease in Juvenile Idiopathic Arthritis

Objective.

This study aimed to test fecal calprotectin (FC) as a screening tool to identify inflammatory bowel disease (IBD) among patients with juvenile idiopathic arthritis (JIA).

Methods.

FC level < 100 g/kg was considered normal. Patients with 2 consecutive FC dosage ≥ 100 g/kg underwent endoscopic evaluation.

Results.

There were 113 patients with JIA enrolled. FC was raised in 7 patients out of 113. All patients had IBD. In 3/7 patients, high FC levels were the only sign consistent with IBD.

Conclusion.

FC is a useful, economical, and noninvasive diagnostic tool to identify JIA patients with underlying IBD.

Use of Laboratory Markers in Addition to Symptoms for Diagnosis of Inflammatory Bowel Disease in Children: A Meta-analysis of Individual Patient Data

Importance

Blood markers and fecal calprotectin are used in the diagnostic workup for inflammatory bowel disease (IBD) in pediatric patients. Any added diagnostic value of these laboratory markers remains unclear.

Objective

To determine whether adding laboratory markers to evaluation of signs and symptoms improves accuracy when diagnosing pediatric IBD.

Data Sources

A literature search of MEDLINE and EMBASE from inception through September 26, 2016. Studies were identified using indexing terms and free-text words related to child, target condition IBD, and diagnostic accuracy.

Study Selection

Two reviewers independently selected studies evaluating the diagnostic accuracy of more than 1 blood marker or fecal calprotectin for IBD, confirmed by endoscopy and histopathology or clinical follow-up, in pediatric patients with chronic gastrointestinal symptoms. Studies that included healthy controls and/or patients with known IBD were excluded.

Data Extraction and Synthesis

Individual patient data from each eligible study were requested from the authors. In addition, 2 reviewers independently assessed quality with Quality Assessment of Diagnostic Accuracy Studies-2.

Mean Outcomes and Measures

Laboratory markers were added as a single test to a basic prediction model based on symptoms. Outcome measures were improvement of discrimination by adding markers as a single test and improvement of risk classification of pediatric patients by adding the best marker.

Results

Of the 16 eligible studies, authors of 8 studies (n = 1120 patients) provided their data sets. All blood markers and fecal calprotectin individually significantly improved the discrimination between pediatric patients with and those without IBD, when added to evaluation of symptoms. The best marker-fecal calprotectin-improved the area under the curve of symptoms by 0.26 (95% CI, 0.21-0.31). The second best marker-erythrocyte sedimentation rate-improved the area under the curve of symptoms by 0.16 (95% CI, 0.11-0.21). When fecal calprotectin was added to the model, the proportion of patients without IBD correctly classified as low risk of IBD increased from 33% to 91%. The proportion of patients with IBD incorrectly classified as low risk of IBD decreased from 16% to 9%. The proportion of the total number of patients assigned to the intermediate-risk category decreased from 55% to 6%.

Conclusions and Relevance

In a hospital setting, fecal calprotectin added the most diagnostic value to symptoms compared with blood markers. Adding fecal calprotectin to the diagnostic workup of pediatric patients with symptoms suggestive of IBD considerably decreased the number of patients in the group in whom challenges in clinical decision making are most prevalent.

Can ultrasound be used as the primary imaging in children with suspected Crohn disease?

BACKGROUND

There is growing literature on the use of ultrasound (US) for evaluation of Crohn disease in adults, but few studies have been conducted on children. Several studies demonstrated high accuracy of US in the diagnosis of Crohn disease. Using US as the primary screening imaging modality for Crohn disease can reduce health care costs, the need for sedation and ionizing radiation exposure.

OBJECTIVE

The aim of our study is to determine if US can be used for screening evaluation of pediatric Crohn disease.

MATERIALS AND METHODS

A prospective cohort study of pediatric patients undergoing MR enterography (MRE) for suspected or known history of Crohn disease was performed, with gray-scale and Doppler US of the terminal ileum done immediately before or after MRE. US images were interpreted by two radiologists (Reader 1 and Reader 2) not involved in image acquisition, in blinded and randomized fashion. US findings of Crohn disease including bowel wall thickening, wall stratification, increased vascularity on Doppler, lymphadenopathy, fat infiltration and extraintestinal complications were evaluated. MRE findings of terminal ileitis were considered the reference standard. Demographic data, body mass index (BMI), symptoms, and laboratory, endoscopic and histopathological data were obtained from electronic medical records.

RESULTS

Forty-one patients (mean age: 13.7 years: 4.6-18.9 years) were evaluated. Mean BMI was 21.2 (range: 13-40.2); 10 patients (24.3%) were either overweight or obese. Final diagnoses were Crohn disease (n=24), ulcerative colitis (n=4) and normal/non-inflammatory bowel disease-related diagnoses (n=13). US demonstrated sensitivity of 67% and 78% and specificity of 78% and 83%, by Reader 1 and Reader 2, respectively. MRE sensitivity and specificity were 75% and 100%, respectively, compared to final clinicopathological diagnosis. Interobserver agreement between Reader 1 and Reader 2 was good (0.6< kappa <0.8).

CONCLUSION

In screening for Crohn disease in children, US has limited sensitivity for detecting terminal ileitis.

Correlation of rapid point-of-care vs send-out fecal calprotectin monitoring in pediatric inflammatory bowel disease

AIM

To assess the correlation between the send-out enzyme-linked immuno sorbent assay (ELISA) and the point-of-care (POC) calprotectin test in pediatric inflammatory bowel disease (IBD) patients.

METHODS

We prospectively collected stool samples in pediatric IBD patients for concomitant send-out ELISA analysis and POC calprotectin testing using the Quantum Blue^® (QB) Extended immunoassay. Continuous results between 17 to 1000 μg/g were considered for comparison. Agreement between the two tests was measured by a Bland-Altman plot and statistical significance was determined using Pitman’s test.

RESULTS

Forty-nine stool samples were collected from 31 pediatric IBD patients. The overall means for the rapid and ELISA tests were 580.5 and 522.87 μg/g respectively. Among the 49 samples, 18 (37.5%) had POC calprotectin levels of ≤ 250 μg/g and 31 (62.5%) had levels > 250 μg/g. Calprotectin levels ≤ 250 μg/g show good correlation between the two assays. Less correlation was observed at quantitatively higher calprotectin levels.

CONCLUSION

In pediatric IBD patients, there is better correlation of between ELISA and POC calprotectin measurements at clinically meaningful, low-range levels. Future adoption of POC calprotectin testing in the United States may have utility for guiding clinical decision making in real time.

Comparison of Fecal Calprotectin Methods for Predicting Relapse of Pediatric Inflammatory Bowel Disease

Background. Pediatric inflammatory bowel disease (IBD) is on the rise worldwide. Endoscopies are necessary for IBD assessment but are invasive, expensive, and inconvenient. Recently, fecal calprotectin (FCal) was proposed as a noninvasive and specific marker of gut inflammation. We evaluated the analytical performance of three FCal assays and their clinical performance in predicting relapse in pediatric IBD. Methods. This study used 40 pediatric IBD and 40 random non-IBD patients' fecal samples. Two automated ELISAs (Bühlmann and PhiCal® Calprotectin-EIA) and an EliA (Phadia 250 EliA-Calprotectin) were used to evaluate the analytical performance. The clinical performance was assessed by PhiCal Calprotectin-EIA, EliA-Calprotectin, and Bühlmann immunochromatographic point-of-care test (POCT). Results. All assays displayed acceptable analytical performance below and above the medical decision cut-off [imprecision (CV < 10% intra-assay; <15% interassay); linearity (overall mean % deviation < 16.5%)]. The agreement with PhiCal Calprotectin-EIA was 100% and 78.6% for Bühlmann (95% CI, 87.5-100; Kappa: 1) and EliA-Calprotectin (95% CI, 60.5-89.8; Kappa: 0.32), respectively, and 63.6% between Bühlmann and EliA-Calprotectin (95% CI, 46.6-77.8; Kappa: 0.16). All assays evaluated had similar clinical performance [AUC: 0.84 (EliA-Calprotectin); 0.83 (POCT and PhiCal Calprotectin-EIA)]. Conclusion. FCal levels determined using the same method and assay together with clinical history would be a noninvasive and useful tool in monitoring pediatric IBD.

Diagnostic Accuracy of Fecal Calprotectin for Pediatric Inflammatory Bowel Disease in Primary Care: A Prospective Cohort Study

PURPOSE

In specialist care, fecal calprotectin (FCal) is a commonly used noninvasive diagnostic test for ruling out inflammatory bowel disease (IBD) in children with chronic gastrointestinal symptoms. The aim of this study was to evaluate the diagnostic accuracy of FCal for IBD in symptomatic children in primary care.

METHODS

We studied 2 prospective cohorts of children with chronic diarrhea, recurrent abdominal pain, or both: children initially seen in primary care (primary care cohort) and children referred to specialist care (referred cohort). FCal (index test) was measured at baseline and compared with 1 of the 2 reference standards for IBD: endoscopic assessment or 1-year follow-up. Physicians were blinded to FCal results, and values greater than 50 μg/g feces were considered positive. We determined specificity in the primary care cohort and sensitivity in the referred cohort.

RESULTS

None of the 114 children in the primary care cohort ultimately received a diagnosis of IBD. The specificity of FCal in the primary care cohort was 0.87 (95% CI, 0.80-0.92). Among the 90 children in the referred cohort, 17 (19%) ultimately received a diagnosis of IBD. The sensitivity of FCal in the referred cohort was 0.99 (95% CI, 0.81-1.00).

CONCLUSIONS

The findings of this study suggest that a positive FCal result in children with chronic gastrointestinal symptoms seen in primary care is not likely to be indicative of IBD. A negative FCal result is likely to be a true negative, which safely rules out IBD in children in whom a primary care physician considers referral to specialist care.

ACR Appropriateness Criteria Crohn Disease

Crohn disease is a chronic inflammatory disorder involving the gastrointestinal tract, characterized by episodic flares and times of remission. Underlying structural damage occurs progressively, with recurrent bouts of inflammation. The diagnosis and management of this disease process is dependent on several clinical, laboratory, imaging, endoscopic, and histologic factors. In recent years, with the maturation of CT enterography, and MR enterography, imaging has played an increasingly important role in relation to Crohn Disease. In addition to these specialized examination modalities, ultrasound and routine CT have potential uses. Fluoroscopy, radiography, and nuclear medicine may be less beneficial depending on the clinical scenario. The imaging modality best suited to evaluating this disease may change, depending on the target population, severity of presentation, and specific clinical situation. This document presents seven clinical scenarios (variants) in both the adult and pediatric populations and rates the appropriateness of the available imaging options. They are summarized in a consolidated table, and the underlying rationale and supporting literature are presented in the accompanying narrative. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every three years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Particularities of Crohn's disease in pediatric patients: current status and perspectives regarding imaging modalities

A consensus on the best imaging modality evaluating inflammatory bowel disease in the pediatric population is lacking and it is often unclear which modality to choose in specific clinical circumstances. Children with inflammatory bowel disease are exposed to ionizing radiation from multiple imaging studies performed at initial diagnosis, throughout treatment and during the follow-up period. This paper discusses the value of different imaging techniques in pediatric patients with inflammatory bowel disease and gives a review of the literature. In addition, particular features of inflammatory bowel disease in children including the predilection of affected segments in the gastrointestinal tract are highlighted. Based on current literature knowledge, we encourage an integrative approach to the interpretation of clinical and imaging data for diagnosis and follow-up in daily clinical settings.

Fecal Calprotectin in Healthy Children Aged 1-4 Years

Objective

Calprotectin has been well emulated recently in adults as well as in children. The aim of this study was to assess fecal calprotectin concentrations in healthy children aged from 1 to 4 years.

Methods

Volunteers were enlisted from 3 nurseries. A brief questionnaire was used to ensure these children meet the inclusion criteria, and some clinical and sociodemographic factors were collected. Anthro software (version 3.1) was used to calculated Length-for-age Z-scores (LAZ), weight-for-age Z-scores (WAZ), and weight-for-length Z-scores (WLZ) respectively. Fecal calprotectin was detected by a commercially available ELISA.

Results

In total 274 children were recruited, with age ranging from 1 to 4 years old. The median FC concentration was 83.19 μg/g [range 4.58 to 702.50 μg/g, interquartile range (IQR) 14.69–419.45 μg/g] or 1.92 log10 μg/g (range 0.66 log10 to 2.85 log10 μg/g, IQR 1.17 log10-2.62 log10 μg/g). All of the children were divided into three groups, 1–2 years (12–24 months), 2–3 years (24–36 months), 3–4 years (36–48 months), with median FC concentrations 96.14 μg/g (1.98 log10 μg/g), 81.48 μg/g (1.91 log10 μg/g), 65.36 μg/g (1.82 log10 μg/g), respectively. There was similar FC level between boys and girls. FC concentrations showed a downward trend by the growing age groups. A statistic difference was found in FC concentrations among groups 1–2 years, 2–3 years and 3–4 years (P = 0.016). In inter-groups comparison, a significant difference was found between children aged 1–2 years and children aged 3–4 years (P = 0.007). A negative correlation trend was found between age and FC concentration (Spearman's rho = -0.167, P = 0.005) in all the participants. A simple correlation was performed among WLZ, WAZ, birth weight, or birth length with FC, and there was no correlation being observed.

Conclusion

Children aged from 1 to 4 years old have lower FC concentrations compared with healthy infants (<1years), and higher FC concentrations when comparing with children older than 4 years and adults.

Management of children with prolonged diarrhea

Prolonged diarrhea is usually defined as acute-onset diarrhea lasting 7 days or more, but less than 14 days. Its trend has been declining in recent years because of improvement in the management of acute diarrhea, which represents the ideal strategy to prevent prolonged diarrhea. The pathogenesis of prolonged diarrhea is multifactorial and essentially based on persistent mucosal damage due to specific infections or sequential infections with different pathogens, host-related factors including micronutrient and/or vitamin deficiency, undernutrition and immunodeficiency, high mucosal permeability due to previous infectious processes and nutrient deficiency with consequential malabsorption, and microbiota disruption. Infections seem to play a major role in causing prolonged diarrhea in both developing and developed areas. However, single etiologic pathogens have not been identified, and the pattern of agents varies according to settings, host risk factors, and previous use of antibiotics and other drugs. The management of prolonged diarrhea is complex. Because of the wide etiologic spectrum, diagnostic algorithms should take into consideration the age of the patient, clinical and epidemiological factors, and the nutritional status and should always include a search for enteric pathogens. Often, expensive laboratory evaluations are of little benefit in guiding therapy, and an empirical approach may be effective in the majority of cases. The presence or absence of weight loss is crucial for driving the initial management of prolonged diarrhea. If there is no weight loss, generally there is no need for further evaluation. If weight loss is present, empiric anti-infectious therapy or elimination diet may be considered once specific etiologies have been excluded.

Noninvasive Tests for Inflammatory Bowel Disease: A Meta-analysis

BACKGROUND

The clinical presentation of pediatric inflammatory bowel disease (IBD) is often nonspecific and overlaps with functional gastrointestinal disorders.

OBJECTIVE

To determine the diagnostic accuracy of symptoms, signs, noninvasive tests, and test combinations that can assist the clinician with the diagnosis of IBD in symptomatic children.

METHODS

A literature search was conducted of Medline and Embase. Two reviewers independently selected studies reporting on the diagnostic accuracy of tests for IBD, with confirmation by endoscopy and histopathology or clinical follow-up, in children with chronic gastrointestinal symptoms. Two reviewers independently extracted data and assessed study quality with the QUADAS-2, an evidence-based quality assessment tool for diagnostic accuracy studies.

RESULTS

Nineteen studies were included (N = 2806). Symptoms (abdominal pain, diarrhea, rectal bleeding, and weight loss) had pooled sensitivities ranging from 0.48 to 0.82 and specificities ranging from 0.17 to 0.78. Of all the blood markers, C-reactive protein (CRP) (9 studies) and albumin (6 studies) had the best performance, with pooled sensitivities of 0.63 (0.51-0.73) and 0.48 (0.31-0.66), respectively, and specificities of 0.88 (0.80-0.93) and 0.94 (0.86-0.98). Assessment of fecal calprotectin (FCal) (10 studies) had a pooled sensitivity of 0.99 (0.92-1.00) and a specificity of 0.65 (0.54-0.74). One limitation was that none of the studies was conducted in nonreferred children.

CONCLUSIONS

In children whose pediatrician is considering an endoscopy, symptoms are not accurate enough to identify low-risk patients in whom an endoscopy can be avoided. FCal, CRP, and albumin findings are potentially of clinical value, given their ability to select children at low risk (negative FCal test result) or high risk (positive CRP or albumin test result) for IBD.

Fecal calprotectin and its correlation with inflammatory markers and endoscopy in patients from India with inflammatory bowel disease

INTRODUCTION

In clinical practice, endoscopic findings are often used for assessing disease activity in inflammatory bowel disease (IBD). In recent years, blood and stool markers are being increasingly used for this purpose. Among them, the fecal calprotectin (FC) level is probably the most favored. Data on the reliability of FC are lacking from countries like India, where gut infections are common.

OBJECTIVE

The aims of this study were to compare the FC level with the erythrocyte sedimentation rate (ESR) and the C-reactive protein (CRP) as non-invasive markers of IBD and, in patients with ulcerative colitis (UC), and to study its correlation with disease extent, clinical activity, and endoscopic severity.

METHODS

Records of patients with IBD who had tests for FC, ESR and CRP and colonoscopy done within a 2-week period, between 2012 and 2014, were retrieved. Sixty-three patients (UC 32, Crohn's disease [CD] 31) were included for analysis. ESR, CRP and FC were compared to endoscopy to assess inflammation.

RESULTS

Patients with UC had higher levels of FC than those with ileocolonic CD (median FC 800 mcg/g vs. 619 mcg/g, respectively; p = 0.04). FC levels correlated with CRP (r = 0.4, p < 0.001) but not with ESR (r = 0.21, p = 0.09). In patients with UC with endoscopic evidence of inflammation, more (86.9 %) had FC > 200 mcg/g (cut-off for disease activity in our laboratory) than had ESR >20 mm in the first hour (60.6 %) or positive CRP (65.6 %) (< 0.01); FC levels increased with increasing endoscopic Mayo score (p = 0.001) and Truelove-Witt's clinical severity score (p = 0.006), but did not correlate with disease extent (p = 0.7). The best FC cut-off level to identify 'active UC' (Mayo grade 2 or more) was 800 mcg/g.

CONCLUSION

Fecal calprotectin level correlates with CRP but not with ESR. In patients with UC with inflammation, FC > 200 mcg/g is more often positive than raised ESR or CRP; it also correlates with clinical and endoscopic activity but not with disease extent. FC level > 800 mcg/g can be used to differentiate active from inactive UC.

Ultrasound features of pediatric Crohn disease: a guide for case interpretation

With the emerging use of ultrasound in the evaluation of children with Crohn disease presenting with acute abdominal symptoms, there is a need to become familiar with the sonographic features of this disease. Our aim is to provide a primer of the characteristic intramural and extramural US findings in children with Crohn disease to serve as a practical and systematic guide to interpretation.

Use of Imaging Techniques in Inflammatory Bowel Diseases That Minimize Radiation Exposure

The use of imaging in the management of inflammatory bowel disease (IBD) has grown exponentially in the last few years. This has raised concerns about the risk of high cumulative level of radiation exposure from medical imaging in IBD patients during their lifetime, especially when the disease begins in pediatric age. Physicians caring for IBD children should be aware of the malignant potential of ionizing radiation and of the availability of alternative radiation-free techniques such as magnetic resonance imaging (MRI) and ultrasonography (US), in order to use them whenever possible. This review will focus on the value of US and MRI in pediatric IBD.

Pediatric Small Bowel Crohn Disease: Correlation of US and MR Enterography

Small bowel Crohn disease is commonly diagnosed during the pediatric period, and recent investigations show that its incidence is increasing in this age group. Diagnosis and follow-up of this condition are commonly based on a combination of patient history and physical examination, disease activity surveys, laboratory assessment, and endoscopy with biopsy, but imaging also plays a central role. Ultrasonography (US) is an underutilized well-tolerated imaging modality for screening and follow-up of small bowel Crohn disease in children and adolescents. US has numerous advantages over computed tomographic (CT) enterography and magnetic resonance (MR) enterography, including low cost and no required use of oral or intravenous contrast material. US also has the potential to provide images with higher spatial resolution than those obtained at CT enterography and MR enterography, allows faster examination than does MR enterography, does not involve ionizing radiation, and does not require sedation or general anesthesia. US accurately depicts small bowel and mesenteric changes related to pediatric Crohn disease, and US findings show a high correlation with MR imaging findings in this patient population.

Faecal calprotectin in suspected paediatric inflammatory bowel disease

OBJECTIVES

The diagnostic accuracy of faecal calprotectin (FC) concentration for paediatric inflammatory bowel disease (IBD) is well described at the population level, but not at the individual level. We reassessed the diagnostic accuracy of FC in children with suspected IBD and developed an individual risk prediction rule using individual patient data.

METHODS

MEDLINE, EMBASE, DARE, and MEDION databases were searched to identify cohort studies evaluating the diagnostic performance of FC in paediatric patients suspected of having IBD. A standard study-level meta-analysis was performed. In an individual patient data meta-analysis, we reanalysed the diagnostic accuracy on a merged patient dataset. Using logistic regression analysis we investigated whether and how the FC value and patient characteristics influence the diagnostic precision. A prediction rule was derived for use in clinical practice and implemented in a spreadsheet calculator.

RESULTS

According to the study-level meta-analysis (9 studies, describing 853 patients), FC has a high overall sensitivity of 0.97 (95% confidence interval [CI] 0.92-0.99) and a specificity of 0.70 (0.59-0.79) for diagnosing IBD. In the patient-level pooled analysis of 742 patients from 8 diagnostic accuracy studies, we calculated that at an FC cutoff level of 50 μg/g there would be 17% (95% CI 15-20) false-positive and 2% (1-3) false-negative results. The final logistic regression model was based on individual data of 545 patients and included both FC level and age. The area under the receiver operating characteristic curve of this derived prediction model was 0.92 (95% CI 0.89-0.94).

CONCLUSIONS

In high-prevalence circumstances, FC can be used as a noninvasive biomarker of paediatric IBD with only a small risk of missing cases. To quantify the individual patients' risk, we developed a simple prediction model based on FC concentration and age. Although the derived prediction rule cannot substitute the clinical diagnostic process, it can help in selecting patients for endoscopic evaluation.

Fecal Calprotectin is an Accurate Tool and Correlated to Seo Index in Prediction of Relapse in Iranian Patients With Ulcerative Colitis

Background:

The natural clinical course of Ulcerative Colitis (UC) is characterized by episodes of relapse and remission. Fecal Calprotectin (FC) is a relatively new marker of intestinal inflammation and is an available, non-expensive tool for predicting relapse of quiescent UC. The Seo colitis activity index is a clinical index for assessment of the severity of UC.

Objectives:

The present study aimed to evaluate the accuracy of FC and the Seo colitis activity index and their correlation in prediction of UC exacerbation.

Patients and Methods:

In this prospective cohort study, 157 patients with clinical and endoscopic diagnosis of UC selected randomly from 1273 registered patients in Fars province’s IBD registry center in Shiraz, Iran, were followed from October 2012 to October 2013 for 12 months or shorter, if they had a relapse. Two patients left the study before completion and one patient had relapse because of discontinuation of drugs. The participants' clinical and serum factors were evaluated every three months. Furthermore, stool samples were collected at the beginning of study and every three months and FC concentration (commercially available enzyme linked immunoassay) and the Seo Index were assessed. Then univariate analysis, multiple variable logistic regression, Receiver Operating Characteristics (ROC) curve analysis, and Pearson’s correlation test (r) were used for statistical analysis of data.

Results:

According to the results, 74 patients (48.1%) relapsed during the follow-up (33 men and 41 women). Mean ± SD of FC was 862.82 ± 655.97 μg/g and 163.19 ± 215.85 μg/g in relapsing and non-relapsing patients, respectively (P < 0.001). Multiple logistic regression analysis revealed that age, number of previous relapses, FC and the Seo index were significant predictors of relapse. ROC curve analysis of FC level and Seo activity index for prediction of relapse demonstrated area under the curve of 0.882 (P < 0.001) and 0.92 1(P < 0.001), respectively. Besides, FC level of 341 μg/g was identified as the cut-off point with 11.2% and 79.7% relapse rate below and above this point, respectively. Additionally, Pearson correlation coefficient (r) between FC and the Seo index was significant in prediction of relapse (r = 0.63, P < 0.001).

Conclusions:

As a simple and noninvasive marker, FC is highly accurate and significantly correlated to the Seo activity index in prediction of relapse in the course of quiescent UC in Iranian patients.

Magnetic resonance enterography, small-intestine contrast US, and capsule endoscopy to evaluate the small bowel in pediatric Crohn's disease: a prospective, blinded, comparison study

BACKGROUND

Small-bowel (SB) disease is a severe clinical entity among the phenotypes of Crohn's disease (CD).

OBJECTIVE

To assess sensitivity, specificity, and accuracy of magnetic resonance enterography (MRE), small-intestine contrast US (SICUS), and capsule endoscopy (CE) in the diagnosis of pediatric SB-CD.

DESIGN

Prospective, blinded, comparison study.

SETTING

Tertiary center for pediatric inflammatory bowel disease.

PATIENTS

Children with known or suspected CD. Diagnosis of SB obstruction at SICUS or MRE excluded patients from the study.

INTERVENTION

Patients underwent ileocolonoscopy, MRE, SICUS, and CE over a 7-day period. For the imaging evaluation, SB was divided into 3 segments: jejunum, proximal and mid ileum, and terminal ileum.

MAIN OUTCOME MEASUREMENTS

The performance of each method was compared to a consensus reference standard for upper SB and to ileocolonoscopy for the terminal ileum.

RESULTS

Twenty-five patients completed the study. In the jejunum, the sensitivity of SICUS and CE was 92%, which was not significantly higher than MRE (75%); the specificity of CE (61%) was significantly lower than that of MRE (P = .04). In the proximal and mid ileum, MRE and CE did not have significantly higher sensitivity (100%) than SICUS (80%), but CE was less specific (P > .05). At the terminal ileum, SICUS and MRE were slightly more sensitive than CE (94% vs. 81%); however, the latter was more specific.

LIMITATIONS

Use of the consensus reference standard for upper SB. Small number of patients.

CONCLUSION

SICUS, MRE, and CE are all effective options for imaging SB. An integrated use of different tools should be suggested to achieve a complete assessment of the SB in children with suspected or confirmed CD.

Accuracy and cost of diagnostic strategies for patients with suspected Crohn's disease

OBJECTIVE

To evaluate accuracy and cost of non-invasive diagnostic strategies including magnetic resonance imaging, intestinal ultrasonography, ileocolonoscopy and video-capsule endoscopy in suspected Crohn's disease.

METHODS

A decision-analytic model was used to assess the costs in low (25%), intermediate (50%) or high (75%) pre-test probability of Crohn's disease. Based on the published accuracy of diagnostic modalities and Bayes' rule, we calculated post-test probability of Crohn's disease using different strategies, starting from ileocolonoscopy, ultrasonography or magnetic resonance. Each strategy was considered successful when post-test probability was >95% or <5%.

RESULTS

With low pre-test probability, only ileocolonoscopy as the first investigation could exclude or confirm Crohn's disease while a normal ultrasonography may exclude Crohn's disease. With high pre-test probability, ileocolonoscopy or ultrasonography as the first test may confirm Crohn's disease, but at least 3 negative tests are required to exclude Crohn's disease. The cost to diagnose one patient was cheapest utilising an ultrasonography-based strategy both in low (ultrasonography €1076; ileocolonoscopy €2005; magnetic resonance €4515) and high pre-test probability of Crohn's disease (ultrasonography €321; ileocolonoscopy €712; magnetic resonance €1412).

CONCLUSION

The accuracy and cost of these strategies depend on pre-test probability of Crohn's disease and vary according to the first test used. Ileocolonoscopy plus ultrasonography is the most accurate and less expensive initial diagnostic strategy.

Imaging in the evaluation of the young patient with inflammatory bowel disease: what the gastroenterologist needs to know

Imaging plays a pivotal role in the diagnosis and management of children and young adults with inflammatory bowel disease. The clinician is presented with numerous imaging options, and it can be challenging to decide which test is the best option. In this article we review the present imaging techniques available in the evaluation of inflammatory bowel disease, with emphasis on the advantages, disadvantages, and radiation burden of each test. Finally, we highlight a few common clinical scenarios and propose an imaging algorithm to approach these diagnostic challenges.

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

The diagnosis and monitoring of Crohn's disease has traditionally relied on clinical assessment, serum markers of inflammation, and endoscopic examination. Fecal biomarkers such as calprotectin, lactoferrin, and S100A12 are predominantly derived from neutrophils, are easily detectable in the feces, and are emerging as valuable markers of intestinal inflammation. This review focuses on the role of fecal biomarkers in the diagnosis and monitoring of Crohn's disease, in particular how these biomarkers change with disease activity and remission, how they can be used to monitor the response to medical therapy, their value in predicting clinical relapse, and their role in monitoring the postoperative state.

The diagnostic accuracy of fecal calprotectin during the investigation of suspected pediatric inflammatory bowel disease: a systematic review and meta-analysis

OBJECTIVES

Fecal calprotectin (FC) is increasingly used during the diagnosis of inflammatory bowel disease (IBD), outperforming blood markers during investigation in children. Tests that reduce endoscopy rates in children with suspected gut inflammation would be beneficial. We aimed to determine the usefulness of FC in children undergoing their primary investigation for suspected IBD by systematic review and meta-analysis.

METHODS

An electronic search was performed with keywords relating to IBD and calprotectin in multiple electronic resources from 1946 to May 2012; a hand search was also performed. Inclusion criteria were studies that reported FC levels before the endoscopic investigation of IBD in patients less than 18 years old. Studies were evaluated using the Quality Assessment of Diagnostic Accuracy Studies tool, and a meta-analysis was performed using a hierarchical summary receiver operating curve model.

RESULTS

Eight papers met the inclusion criteria (six prospective and two retrospective case-control studies); methodological quality was determined in detail for each study. The 8 studies presented FC levels at presentation in 715 patients, 394 pediatric IBD patients, and 321 non-IBD controls. Pooled sensitivity and specificity for the diagnostic utility of FC during the investigation of suspected pediatric IBD were 0.978 (95% confidence interval (CI), 0.947-0.996) and 0.682 (95% CI, 0.502-0.863), respectively; the positive and negative likelihood ratios were 3.07 and 0.03, respectively.

CONCLUSIONS

FC has a high sensitivity and a modest specificity during the diagnosis of suspected pediatric IBD. Further work is required to determine the effect of FC levels on endoscopy rates and its role during the re-evaluation of those with confirmed disease.

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

Diagnosis and monitoring of inflammatory bowel diseases rely on clinical, endoscopic, and radiologic parameters. Inflammatory biomarkers have been investigated as a surrogate marker for endoscopic diagnosis of inflammatory activity. Fecal inflammatory biomarkers such as calprotectin and lactoferrin are direct products of bowel inflammation and provide an accurate and noninvasive diagnostic and monitoring modality for Crohn's disease and ulcerative colitis. This report contains an overview of the currently existing literature pertaining to clinical implications of fecal biomarkers for diagnosis, monitoring, and prediction of outcomes of inflammatory bowel disease.

Diagnostic utility of faecal biomarkers in patients with irritable bowel syndrome

Irritable bowel syndrome (IBS) is a common functional gastrointestinal (GI) disorder characterized by unspecific symptoms. In clinical practice it is crucial to distinguish between non-inflammatory functional problems and inflammatory, malignant or infectious diseases of the GI tract. Differentiation between these involves the use of clinical, radiological, endoscopic, histological and serological techniques, which are invasive, expensive, time-consuming and/or hindered by inaccuracies arising from subjective components. A range of faecal markers now appears to have the potential to greatly assist in the differentiation of inflammatory bowel disease (IBD) and IBS. Faecal markers of neutrophil influx into the mucosa are reliable indicators of intestinal inflammation and their role has been mainly studied in discriminating IBD from non-IBD conditions (including IBS) rather than organic from non-organic diseases. Phagocyte-specific proteins of the S100 family (S100A12, calprotectin) are amongst the most promising faecal biomarkers of inflammation. Faecal leukocyte degranulation markers (lactoferrin, polymorphonuclear elastase and myeloperoxidase) have also been suggested as diagnostic tools for the differentiation of IBD and IBS. More recently, additional proteins, including granins, defensins and matrix-metalloproteases, have been discussed as differential diagnostic markers in IBD and IBS. In this review, some of the most promising faecal markers, which have the potential to differentiate IBD and IBS and to advance diagnostic practices, will be discussed.

Challenges in diagnostic accuracy studies in primary care: the fecal calprotectin example

Background

Low disease prevalence and lack of uniform reference standards in primary care induce methodological challenges for investigating the diagnostic accuracy of a test. We present a study design that copes with these methodological challenges and discuss the methodological implications of our choices, using a quality assessment tool for diagnostic accuracy studies (QUADAS-2).

Design

The study investigates the diagnostic value of fecal calprotectin for detecting inflammatory bowel disease in children presenting with chronic gastrointestinal symptoms in primary care. It is a prospective cohort study including two cohorts of children: one cohort will be recruited in primary care and the other in secondary/tertiary care. Test results of fecal calprotectin will be compared to one of the two reference standards for inflammatory bowel disease: endoscopy with histopathological examination of mucosal biopsies or assessment of clinical symptoms at 1-year follow-up.

Discussion

According to QUADAS-2 the use of two reference standards and the recruitment of patients in two populations may cause differential verification bias and spectrum bias, respectively. The clinical relevance of this potential bias and methods to adjust for this are presented. This study illustrates the importance of awareness of the different kinds of bias that result from choices in the design phase of a diagnostic study in a low prevalence setting. This approach is exemplary for other diagnostic research in primary care.

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.

Can Fecal Calprotectin Level Be Used as a Markers of Inflammation in the Diagnosis and Follow-Up of Cow's Milk Protein Allergy?

Purpose

Calprotectin is a cytosolic protein with immunomodulatory, antimicrobial, and antiproliferative actions. The concentration of calprotectin increases in infection, inflammation, and malignancy. We determined if calprotectin can be used as a marker for the diagnosis and follow-up of bowel inflammation in cow's milk protein allergy (CMPA).

Methods

In total, 32 patients newly diagnosed with CMPA were included (24 IgE-mediated, 8 non-IgE-mediated). In all subjects, a complete blood count, total IgE, cow's milk-specific IgE, and fecal calprotectin (FC) were assessed before and after a cow's milk protein (CMP) elimination diet was started. The results were compared with those of 39 healthy children.

Results

The mean FC value before the CMP elimination diet was 516±311 µg/g in the 32 patients with CMPA and 296±94 µg/g in the control group (P=0.011). The mean FC value after the diet in these patients was 254±169 µg/g, which was significantly different from the mean value before the CMP elimination diet (P<0.001). When we compared FC levels before the CMP elimination diet in the IgE-mediated group with the control group, we found no significant statistical difference (P=0.142). The mean FC value before the CMP elimination diet was 886±278 µg/g in the non-IgE-mediated group and 296±94 µg/g in the control group; this difference was statistically significant (P<0.001). In the IgE-mediated and non-IgE-mediated groups, FC values after CMP elimination diet were 218±90 µg/g and 359±288 µg/g, respectively, and FC values before CMP elimination diet were 392±209 µg/g and 886±278 µg/g, respectively; these differences were statistically significant (P=0.001 and P=0.025, respectively).

Conclusions

FC levels may be a useful marker for follow-up treatment and recurrence determination in CMPA.

Investigation of chronic diarrhoea in infancy

Diarrhoea in infants and young children is defined as >200g/day of stools, and occurs when there is an imbalance between intestinal fluids absorption and secretion. This may be caused by either a decreased absorption (osmotic diarrhoea) or an increased secretion (secretory diarrhoea). Chronic diarrhoea defines intestinal loss of water and electrolytes with increased stool frequency, reduced consistency and larger volume over more than 14days. This disorder in children shows a wide range of aetiologies depending on the age. The knowledge of common and rare aetiologies is important to optimize the diagnostic approach. A stepwise approach, starting with a comprehensive history, physical examination, inspection and collection of stool samples, helps to devise appropriate diagnostic and therapeutic management. In this article we discuss the pathophysiology, aetiology and possible approach to chronic diarrhoea in infancy.

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.

The role of calprotectin in pediatric disease

Calprotectin (CP) is a calcium- and zinc-binding protein of the S100 family expressed mainly by neutrophils with important extracellular activity. The aim of the current review is to summarize the latest findings concerning the role of CP in a diverse range of inflammatory and noninflammatory conditions among children. Increasing evidence suggests the implication of CP in the diagnosis, followup, assessment of relapses, and response to treatment in pediatric pathological conditions, such as inflammatory bowel disease, necrotizing enterocolitis, celiac disease, intestinal cystic fibrosis, acute appendicitis, juvenile idiopathic arthritis, Kawasaki disease, polymyositis-dermatomyositis, glomerulonephritis, IgA nephropathy, malaria, HIV infection, hyperzincemia and hypercalprotectinemia, and cancer. Further studies are required to provide insights into the actual role of CP in these pathological processes in pediatrics.

Intestinal CCL11 and eosinophilic inflammation is regulated by myeloid cell-specific RelA/p65 in mice

In inflammatory bowel diseases (IBDs), particularly ulcerative colitis, intestinal macrophages (MΦs), eosinophils, and the eosinophil-selective chemokine CCL11, have been associated with disease pathogenesis. MΦs, a source of CCL11, have been reported to be of a mixed classical (NF-κB-mediated) and alternatively activated (STAT-6-mediated) phenotype. The importance of NF-κB and STAT-6 pathways to the intestinal MΦ/CCL11 response and eosinophilic inflammation in the histopathology of experimental colitis is not yet understood. Our gene array analyses demonstrated elevated STAT-6- and NF-κB-dependent genes in pediatric ulcerative colitis colonic biopsies. Dextran sodium sulfate (DSS) exposure induced STAT-6 and NF-κB activation in mouse intestinal F4/80(+)CD11b(+)Ly6C(hi) (inflammatory) MΦs. DSS-induced CCL11 expression, eosinophilic inflammation, and histopathology were attenuated in RelA/p65(Δmye) mice, but not in the absence of STAT-6. Deletion of p65 in myeloid cells did not affect inflammatory MΦ recruitment or alter apoptosis, but did attenuate LPS-induced cytokine production (IL-6) and Ccl11 expression in purified F4/80(+)CD11b(+)Ly6C(hi) inflammatory MΦs. Molecular and cellular analyses revealed a link between expression of calprotectin (S100a8/S100a9), Ccl11 expression, and eosinophil numbers in the DSS-treated colon. In vitro studies of bone marrow-derived MΦs showed calprotectin-induced CCL11 production via a p65-dependent mechanism. Our results indicate that myeloid cell-specific NF-κB-dependent pathways play an unexpected role in CCL11 expression and maintenance of eosinophilic inflammation in experimental colitis. These data indicate that targeting myeloid cells and NF-κB-dependent pathways may be of therapeutic benefit for the treatment of eosinophilic inflammation and histopathology in IBD.

Tolerance to a new free amino acid-based formula in children with IgE or non-IgE-mediated cow's milk allergy: a randomized controlled clinical trial

Background

Amino acid-based formulas (Aaf) are increasingly used in children with cow’s milk allergy (CMA). To be labeled hypoallergenic these formulas must demonstrate in clinical studies that they don’t provoke reactions in 90% of subjects with confirmed CMA with 95% confidence when given in prospective randomized, double-blind, placebo-controlled challenge (DBPCFC) trials. The majority of available safety data on Aaf derived from patients with IgE-mediated CMA. Considering substantial differences in the immunologic mechanism and clinical presentation of non-IgE-mediated CMA it’s important to investigate the hypoallergenicity of these formulas also in these patients. We prospectively assessed the tolerance to a new commercially available Aaf in children affected by IgE- or non-IgE-mediated CMA.

Methods

Consecutive patients affected by IgE- or non-IgE-mediated CMA, aged ≤ 4 years, were enrolled. DBPCFC was carried out with increasing doses of the new Aaf (Sineall, Humana, Milan, Italy), using validated Aaf as placebo. Faecal concentrations of calprotectin (FC) and eosinophilic cationic protein (ECP) were monitored.

Results

Sixty patients (44 male, 73.3%, median age 37, 95%CI 34.5–39.6 months, IgE-mediated CMA 29, 48.3%) were enrolled. At the diagnosis clinical symptoms were gastrointestinal (46.6%), cutaneous (36.6%), respiratory (23.3%), and systemic (10.0%). After DBPCFC with the new Aaf, no patient presented early or delayed clinical reactions. Faecal concentration of calprotectin and of ECP remained stable after the exposure to the new Aaf.

Conclusions

The new Aaf is well tolerated in children with IgE- or non-IgE-mediated CMA, and it could be used as a safe dietotherapy regimen for children with this condition.

Trial registration

The trial was registered in the ClinicalTrials.gov Protocol Registration System (ID number: NCT01622426).

Fecal calprotectin in pediatric inflammatory bowel disease: a systematic review

BACKGROUND

Inflammatory bowel disease frequently begins during childhood or adolescence. Current tests and procedures for diagnosing and monitoring inflammatory bowel disease are invasive, uncomfortable and costly. Fecal calprotectin is an inflammatory marker tested in several studies including pediatric patients with inflammatory bowel disease.

METHODS

A search for articles published up to October 2011 was conducted using MEDLINE and EMBASE databases. We included original English-written articles referred to pediatric patients with inflammatory bowel disease and measured fecal calprotectin levels. We extracted data concerning fecal calprotectin levels in patients with inflammatory bowel disease and in the controls groups, sensitivity, specificity, positive and negative likelihood ratio.

RESULTS

Thirty-four studies were included. Fecal calprotectin levels of patients with inflammatory bowel disease are much higher than those of healthy controls or patients with functional disorders or other gastrointestinal diseases. The results vary greatly when taking all studies into consideration. Nevertheless, in cases of newly diagnosed and/or active inflammatory bowel disease, the results are more homogeneous, with high sensitivity and positive likelihood ratio, low negative likelihood ratio, but moderate specificity. Moreover, 50 μg/g seems to be the most proper cut-off point for the fecal calprotectin test.

CONCLUSIONS

The fecal calprotectin test could be used for supporting diagnosis or confirming relapse of inflammatory bowel disease in pediatric patients. A positive result could confirm the suspicion of either inflammatory bowel disease diagnosis or inflammatory bowel disease relapse, due to the high sensitivity of the test, but a negative result should not exclude these conditions, due to its moderate specificity.

Chronic diarrhoea in children

Chronic diarrhoea in children shows an age related spectrum. In infants and young children a major role is related to persistent intestinal infections, intolerance to specific nutrients such as cow's milk protein, and toddler's diarrhoea. In older children and adolescents, inflammatory bowel diseases are strongly increasing and nonspecific diarrhoea is also frequent. Coeliac disease is a major cause of diarrhoea throughout childhood. In neonates, congenital diarrhoea is a rare but severe syndrome that includes several highly complex diseases. In children, diagnosis should be based on noninvasive techniques. Endoscopy should be decided based on clinical criteria, but also driven by noninvasive tests to assess the digestive absorptive functions and intestinal inflammation. A stepwise approach may reduce the need of endoscopy, also in the light of its relatively limited diagnostic yield compared to adult patients. Treatment of chronic diarrhoea in children is also substantially different from what is generally done in adults and includes a major role for nutritional interventions. Therefore chronic diarrhoea in children is a complex age-specific disorder that requires an age-specific management that is in many aspects distinct from that in adults.

Investigation of small bowel in pediatric Crohn's disease

Investigation of the small bowel has been traditionally a challenge for pediatric gastroenterologists due to its location, anatomical tortuosity, and invasiveness of the available techniques. Recently, there has been a remarkable improvement in imaging and endoscopic tools aimed at exploring successfully the small intestine in inflammatory bowel disease. The former are represented by ultrasonography (either alone or with administration of oral contrast agents) and by magnetic resonance: both have provided accurate methods to detect structural bowel changes, diminishing patient discomfort and precluding radiation hazard. The use of traditional radiologic techniques such as fluoroscopy have been markedly reduced due to radiation exposure and inability to depict transmural inflammation or extraluminal complications. Among the novel endoscopic tools, capsule endoscopy and balloon-assisted enteroscopy have tremendously opened new diagnostic and therapeutic perspectives, by allowing the direct visualization of small intestinal mucosa and, through enteroscopy, histological diagnosis as well as therapeutic interventions such as stricture dilation and bleeding treatment. These endoscopic techniques should always be preceded by imaging of the intestine in order to identify strictures. This review describes the most recent progress with the employment of novel imaging and endoscopic methodologies for investigating the small bowel in children with suspected or established Crohn's disease.

The diagnostic accuracy of fecal calprotectin during the investigation of suspected pediatric inflammatory bowel disease

OBJECTIVES

Fecal calprotectin (FC) is elevated in patients with inflammatory bowel disease (IBD). Studies evaluating FC during the initial investigation of children with suspected IBD have been limited, especially with regard to their small patient groups. We aimed to evaluate the diagnostic accuracy of FC in a large regional cohort of children undergoing full upper and lower endoscopy for suspected IBD, comparing FC with six common blood parameters.

METHODS

Using a retrospective case-control design all FC measurements carried out between 2005 and 2010 in children <18 years old were obtained. All IBD and non-IBD patients who had a FC measurement available before full endoscopic evaluation for suspected bowel inflammation were examined. FC was measured using the PhiCal Test. Multivariate analyzes and receiver operating characteristic curve generation were used to derive significance.

RESULTS

A total of 190 patients (91 IBD and 99 non-IBD controls) met the inclusion criteria. Median FC at diagnosis for the IBD group was 1,265 μg/g (interquartile range (IQR) 734-2,024 μg/g), compared with 65 μg/g (IQR 20-235 μg/g) in controls (P<0.001). FC levels did not vary significantly between patients with Crohn's disease, ulcerative colitis, and IBD unclassified and were not influenced by age or disease location. FC was found to be far superior to commonly utilized blood parameters such as C-reactive protein and white cell count (both P<0.01), with an area under the curve of 0.93 (95% confidence interval 0.89-0.97).

CONCLUSIONS

This study demonstrates that FC is an invaluable tool in determining those children who may require endoscopy for suspected IBD, and elevated values should prompt further investigation.

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.

Obesity, inflammation and metabolic syndrome in Danish adolescents

AIM

To describe biomarkers of inflammation and markers related to the metabolic syndrome (MS) in healthy obese Danish adolescent and compare to a normal-weight group.

METHODS

Fifty-one obese and 30 normal-weight adolescents (12-15 years) were included. Anthropometry and blood pressure were measured, and blood was sampled.

RESULTS

Obese adolescents had significantly higher blood pressure, insulin, homeostasis model assessment of insulin resistance, C-peptide, total cholesterol, low-density lipoprotein cholesterol (LDL), triglyceride, C-reactive protein (CRP), interleukin-6 and tumour necrosis factor alpha and lower high-density lipoprotein cholesterol values, compared with normal-weight adolescents, whereas there were no differences between the groups for glucose, free fatty acids or faecal calprotectin. Within the obese group insulin, low-density lipoprotein cholesterol, and CRP were positively associated with body mass index (BMI) Z-scores. The MS was present in 14% of obese adolescents. CRP was positively associated with most anthropometric measures within the obese group, and in multiple linear regression analysis both BMI Z-score and the sum of skin folds explained a considerable part (R(2) = 0.421) of the variation in CRP.

CONCLUSION

Otherwise healthy Danish obese adolescents had marked low-grade inflammation, elevated biomarkers of the MS and high prevalence of the MS.

New faecal tests in gastroenterology

Most abdominal disorders present with a limited number of overlapping symptoms. Blood tests are not routinely available for use in diagnosis and so investigation tends to require complex imaging procedures or endoscopy and biopsy. These are invasive for the patient, may be associated with morbidity and mortality and have considerable resource implications. Biochemical tests on a single sample of faeces are therefore a valuable alternative. Measurement of faecal calprotectin has been shown to have a role in the diagnosis of inflammatory bowel disease and in its monitoring. Lactoferrin is also of benefit used in this way. Faecal elastase has been demonstrated to be of use in the diagnosis of pancreatic insufficiency. A number of faecal markers have been explored in colorectal cancer. Faecal occult blood testing is used for population screening, but the metabolomic marker tumour, M2-pyruvate kinase, has potential for use in both diagnosis and screening. DNA testing has advantages in colorectal cancer but the exact applications of such tests require further evaluation.