A minimally invasive diagnostic test that used a capsule attached to a string accurately distinguished active from inactive eosinophilic esophagitis in just 1 hour, according to results of a prospective study.
“Quantification of mucosal eosinophilia provides a meaningful metric to assess inflammation, but endoscopic procurement of mucosal samples has been hampered by the need for anesthesia/sedation, potential complications, high costs, time away from work and school and limited assessment of the full esophageal mucosal surface,” Steven J. Ackerman, PhD, of the departments of biochemistry and molecular genetics, and medicine at the University of Illinois at Chicago, and colleagues wrote. “To address these concerns, a number of studies have sought to identify laboratory, functional, or radiographic biomarkers to replace mucosal eosinophilia as a diagnostic and monitoring metric.”
Researchers performed a study comprising children and adults who were undergoing clinically indicated esophagogastroduodenoscopy (n = 134) and Esophageal String Test (EST) with a dwell time of 1 hour. They placed patients into three groups — active EoE (n = 62), inactive EoE (n = 37) and normal mucosa (n = 35) — and compared eosinophil-associated protein levels in the samples collected through EST and endoscopic biopsy. Lastly, they used statistical modelling to find biomarkers that were correlated with and predicted eosinophilic inflammation.
Ackerman and colleagues found that EST-captured biomarkers correlated with peak eosinophils per high-power field and with endoscopic visual scoring, and had the same proteins as endoscopically collected samples.
Researchers developed an “EoEScore” based on combined eotaxin-3 and major basic protein-1 concentrations. This score was able to distinguish patients with active EoE from those with inactive EoE, as well as from individuals with normal esophageal mucosa.
Most of the patients also reported that they would prefer the test over endoscopy if it provided the same information (87% of children, 95% of parents and 92% of adults).
“Use of this minimally invasive tool can improve the quality of patients’ lives, reduce costs in clinical practice and accelerate progress of therapeutic trials,” Ackerman and colleagues wrote. – by Alex Young
Disclosure s: Ackerman is a coinventor of the Esophageal String test and a cofounder and member of the board of managers of EnteroTrack. Please see the full study for all other authors’ relevant financial disclosures.