Assessing Intestinal Inflammation Using a New Rapid In Vitro Assay That Detects Lactoferrin

Abstract

Purpose: The clinical differentiation of inflammatory bowel disease (IBD) from irritable bowel syndrome (IBS) is a difficult process due to the overlapping variety of symptoms. A rapid diagnosis is essential for determining specific medical therapy and for optimizing patient care. Lactoferrin, a marker of activated neutrophils, is a validated indicator of intestinal inflammation, which offers a noninvasive aid for ruling out IBS and for monitoring disease activity in IBD. The aim of our study was to evaluate a rapid membrane test for detecting elevated fecal lactoferrin (IBD EZ VUE™) in the differentiation of active IBD from IBS and as an indicator of disease activity. Methods: Fecal specimens were collected from 116 patients (94 IBD/22 IBS) and from 27 healthy controls. The male: female ratio was 1:1.9 with 73 pediatric and 70 adult specimens. Uncoded samples were tested for elevated lactoferrin using the rapid membrane assay and results were confirmed by enzyme-linked immunosorbent assay (IBD-CHEK™). Disease diagnosis was based on clinical histories and disease activity was assessed using the Harvey Bradshaw Activity Index (HBAI). Results: Compared with disease diagnosis and activity, the rapid membrane assay differentiated active IBD from IBS and healthy controls with 100% sensitivity, specificity, and correlation for adult patients. Active IBD was separated from inactive IBD in adults with 100% sensitivity, specificity, and correlation. In the pediatric group (0–20 years old), active IBD was differentiated from IBS and healthy controls with 100% sensitivity, 91.7% specificity, and 98.1% correlation. The assay was 100% sensitive and 89.5% specific, with 96.7% correlation for discriminating active IBD from inactive IBD in pediatric patients. Lactoferrin levels in active IBD patients were significantly elevated compared to inactive IBD, IBS, and healthy controls (p < 0.002). Conclusions: The IBD EZ VUE™ rapid membrane assay was sensitive and specific for determining IBD activity in pediatric and adult patients. The test was comparable to the HBAI and lactoferrin ELISA, and rapidly detected elevated lactoferrin to help differentiate IBD from IBS. Periodic testing for lactoferrin in IBD patients can aid the determination of disease state and management of patient care.