One-Hour Esophageal String Test: A Nonendoscopic Minimally Invasive Test That Accurately Detects Disease Activity in Eosinophilic Esophagitis

Steven J. Ackerman, Amir F. Kagalwalla, Ikuo Hirano, Nirmala Gonsalves, Paul Menard Katcher, Sandeep Gupta, Joshua B. Wechsler, Milica Grozdanovic, Zhaoxing Pan, Joanne C. Masterson, Jian Du, Robert J. Fantus, Preeth Alumkal, James J. Lee, Sergei Ochkur, Faria Ahmed, Kelley Capocelli, Hector Melin-Aldana, Kathryn Biette, Allison DubnerKatie Amsden, Kaitlin Keeley, Maureen Sulkowski, Angelika Zalewski, Dan Atkins, Glenn T. Furuta

Research output: Contribution to journalArticle

4 Scopus citations


OBJECTIVES: Eosinophilic esophagitis (EoE), a chronic food allergic disease, lacks sensitive and specific peripheral biomarkers. We hypothesized that levels of EoE-related biomarkers captured using a 1-hour minimally invasive Esophageal String Test (EST) would correlate with mucosal eosinophil counts and tissue concentrations of these same biomarkers. We aimed to determine whether a 1-hour EST accurately distinguishes active from inactive EoE or a normal esophagus. METHODS: In a prospective, multisite study, children and adults (ages 7-55 years) undergoing a clinically indicated esophagogastroduodenoscopy performed an EST with an esophageal dwell time of 1 hour. Subjects were divided into 3 groups: active EoE, inactive EoE, and normal esophageal mucosa. Eosinophil-associated protein levels were compared between EST effluents and esophageal biopsy extracts. Statistical modeling was performed to select biomarkers that best correlated with and predicted eosinophilic inflammation. RESULTS: One hundred thirty-four subjects (74 children, 60 adults) with active EoE (n = 62), inactive EoE (n = 37), and patient controls with a normal esophagus (n = 35) completed the study. EST-captured eosinophil-associated biomarkers correlated significantly with peak eosinophils/high-power field, endoscopic visual scoring, and the same proteins extracted from mucosal biopsies. Statistical modeling, using combined eotaxin-3 and major basic protein-1 concentrations, led to the development of EoE scores that distinguished subjects with active EoE from inactive EoE or normal esophagi. Eighty-seven percent of children, 95% of parents, and 92% of adults preferred the EST over endoscopy if it provided similar information. DISCUSSION: The 1-hour EST accurately distinguishes active from inactive EoE in children and adults and may facilitate monitoring of disease activity in a safe and minimally invasive fashion.

Original languageEnglish (US)
Pages (from-to)1614-1625
Number of pages12
JournalThe American journal of gastroenterology
Issue number10
StatePublished - Oct 1 2019


ASJC Scopus subject areas

  • Hepatology
  • Gastroenterology

Cite this

Ackerman, S. J., Kagalwalla, A. F., Hirano, I., Gonsalves, N., Katcher, P. M., Gupta, S., Wechsler, J. B., Grozdanovic, M., Pan, Z., Masterson, J. C., Du, J., Fantus, R. J., Alumkal, P., Lee, J. J., Ochkur, S., Ahmed, F., Capocelli, K., Melin-Aldana, H., Biette, K., ... Furuta, G. T. (2019). One-Hour Esophageal String Test: A Nonendoscopic Minimally Invasive Test That Accurately Detects Disease Activity in Eosinophilic Esophagitis. The American journal of gastroenterology, 114(10), 1614-1625.