The Role of Environmental Exposures in the Etiology of Eosinophilic Esophagitis: A Systematic Review.

Eosinophilic esophagitis (EoE) is an emerging clinicopathologic entity defined by abnormal esophageal eosinophilic infiltration. Management of this disease is hampered by limited understanding of etiologic and controllable risk factors. The aim of this systematic review was to determine the environmental risk factors for EoE. We searched the PubMed, Web of Science, and EMBASE databases from January 1, 1950, through June 30, 2015. To identify additional relevant studies, we hand searched bibliographies of included articles. We limited the review to articles using human subjects and consisting of case reports, case series, cross-sectional and cohort studies, and clinical trials. Nineteen articles discuss the risk of environmental exposures on EoE and indicate that environment plays a large role in the etiology of EoE. Seasonal, geographic, and climate-based differences in disease prevalence have been reported, but the exact mediators of this process, possibly aeroallergens that vary over time and from place to place, remain elusive.