S380 Can Fecal Calprotectin Help Diagnose Eosinophilic Colitis? A Systematic Review

Introduction: Eosinophilic gastroenteritis disorders (EGIDs) are immune-mediated conditions marked by eosinophilic infiltration in the gastrointestinal (GI) tract. EGIDs are a growing concern as incidence and prevalence have increased over time in both pediatric and adult populations. Its occurrence may be underestimated due to overlapping symptoms with other GI disorders. Diagnosis relies on determining the total number of eosinophils per high power field, specific to the affected GI region. Elevation in fecal calprotectin (FC) correlates with colonic mucosal inflammation and is commonly elevated in inflammatory bowel disease (IBD). FC has the potential to be a cost-effective, noninvasive test to help differentiate EGID, specifically eosinophilic colitis (EC), from other GI conditions. FC utility in EC is not established. The primary objective of this study is to elucidate the relationship between FC levels and EC. Methods: A systematic review was performed using PUBMED, Medline, Web of Science, ClinicalTrials.gov and Scopus from inception to April 2025. Eligible studies included randomized controlled trials, retrospective, prospective studies and case reports with data on patients with FC and EGID. Articles not in English, incomplete demographics and populations with IBD and parasitic infections were excluded. Data including but not limited to patient age, FC value, GI disorder diagnosis and presenting symptoms were collected. Results: Fifteen articles met relevant criteria for review, with a total of 5 articles included. One retrospective study, 1 cross-sectional study, 1 observational study, and 2 case reports were included. A total of 123 patients had a diagnosis of EC. Median FC level for EC patients was 70, with a range of 25-1,070. Median FC level for non-EC patients from 2 studies was 16.2, with a range of 0-50. The median optimal FC cutoff from 2 studies that was used to predict EC was 93.6. The majority of patients with EC had higher FC values than non-EC patients. Conclusion: Elevated FC levels are observed in pediatric and adult populations with EC, though its role in disease monitoring remains unclear. Study heterogeneity is a limitation of this systematic review. FC may serve as a cost-effective, noninvasive method to guide clinicians in diagnosing EC, with subsequent endoscopy needed. Current evidence is limited, relying largely on pediatric populations. More research is required to investigate FC’s role in monitoring treatment response in EC, especially in adults.