Compliance With Fecal Calprotectin Testing in Pediatric Patients With Inflammatory Bowel Disease

Diagnostic Value of Quantitative Contrast-Enhanced Ultrasound in Comparison to Endoscopy in Children With Crohn's Disease

OBJECTIVE

Quantitative contrast-enhanced US (CEUS) provides objective evaluation of bowel wall perfusion and has been reported as a useful method for evaluating Crohn's disease (CD) activity in children. We tested its' diagnostic accuracy in comparison to endoscopy and evaluated its' usefulness in comparison to Pediatric Crohn's Disease Activity Index (PCDAI) and fecal Calprotectin (FC).

MATERIALS AND METHODS

Children with CD and thickened bowel wall on abdominal US were prospectively enrolled. Disease activity was evaluated with quantitative CEUS, PCDAI and FC and compared to a simple endoscopic score for Crohn's disease (SES-CD). Spearman's correlation and Cohen's kappa statistic between the SES-CD and other disease activity measures were performed and diagnostic accuracies calculated.

RESULTS

36 children 3.5-18 years old (mean age 14 years) were included. The quantitative CEUS had 78.57% sensitivity (95%CI 0.59-0.92), 100% specificity (95%CI 0.63-1.0) and 83.33% diagnostic accuracy (95% CI 0.67-0.94). The concordance remission agreement with endoscopy was substantial for quantitative CEUS and PCDAI (quantitative CEUS: κ = 0.62; 95% CI 0.363-0.877; PCDAI: κ = 0.615; 95% CI 0.311-0.920), but only fair for FC (κ = 0.389; 95% CI 0.006-0.783). Correlation between all measures and endoscopy was moderate and statistically significant (quantitative CEUS: r_s  = 0.535, PCDAI: r_s  = 0.543, FC: r_s  = 0.497).

CONCLUSIONS

Quantitative CEUS has a potential of becoming a complementary method for evaluation of CD activity in children due to its' high specificity in comparison to endoscopy. Lower sensitivity makes it deficient as a single measure and further management should be guided by PCDAI and FC results as well.

Validation of the newly FDA-approved Buhlmann fCal Turbo assay for measurement of fecal calprotectin in a pediatric population

Objectives

Inflammatory bowel disease (IBD) is an increasingly prevalent disorder marked by chronic intestinal inflammation. Fecal calprotectin has emerged as a useful biomarker for differential diagnostics and monitoring IBD activity. We validated the newly FDA-approved fCal Turbo fecal calprotectin assay in our pediatric hospital.

Design and methods

The performance of the fCal Turbo assay was assessed on the Vitros 5600 analyzer (Ortho Clinical Diagnostics, USA), including limit of quantitation, linearity, precision, and interference studies. Method comparison was performed with 20 fecal samples with the Buhlmann fCal ELISA, and reference range verification was performed with 33 fecal samples.

Results

The fCal Turbo assay on the Vitros 5600 was linear between 33.1 and 14,182.5 ​μg/g, with dilution studies extending the range to 33.1–22,000 ​μg/g, Reproducibility of the assay met acceptability criteria, with intra-assay CV of 0.3–3.2% and inter-assay CV of 5.2–8.9%. Interference studies identified acceptable thresholds for protein, bilirubin, and lipids. We verified a reference range of 33.1–60 ​μg/g in our patient population. Deming regression identified acceptable correlation with minor positive bias (2.7%) between the fCal Turbo and fCal ELISA methods.

Conclusions

The fCal Turbo assay performs well on the Vitros 5600 analyzer in our patient population, with the assay being easy to use in our routine chemistry workflow. We anticipate that the fCal Turbo assay will be useful as a rapid screening method for differential diagnostics and disease monitoring of IBD in our patient population.

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We validated the fCal Turbo fecal calprotectin assay for pediatric population use.

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This assay meets performance criteria, but cannot be used with turbid specimens.

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This automated assay compares favorably to standard ELISA for turnaround time.

Cutaneous manifestations of metastatic Crohn's disease

Metastatic Crohn's disease is a rare cutaneous complication of primary Crohn's disease. It is a granulomatous inflammatory process, similar to the pathogenic mechanism of Crohn's disease, that occurs in sites discontiguous from the gastrointestinal tract. Metastatic Crohn's disease can precede the development of Crohn's disease by months to years, and children are more likely to present with metastatic Crohn's disease in the absence of gastrointestinal symptoms. Given that approximately 30% of individuals with Crohn's disease present in childhood, early recognition of extraintestinal manifestations of Crohn's disease such as metastatic Crohn's disease can aid in timely diagnosis and management of bowel disease. We present data from two pediatric cases of metastatic Crohn's disease recently seen at our institution in addition to the 61 reported cases of pediatric metastatic Crohn's disease in the literature. This review article will focus on the epidemiology, pathogenesis, clinical features, and histology of and treatment options for pediatric metastatic Crohn's disease.