Eosinophilic esophagitis (EoE), a chronic inflammatory disease of the esophagus, is a clinical and financial burden to patients if left untreated. Often the natural history of the disease includes development of fibrosis and stricturing of the esophagus, acute food impactions, unplanned emergency room visits, and invasive procedures such as endoscopy. Currently there are no Food and Drug Administration (FDA) approved medications for the treatment of EoE. As such, pharmacologic options approved for use in asthma are used for treatment of EoE and include proton pump inhibitors and swallowed topical steroids. These medications are prescribed chronically as EoE is considered a lifelong disease. Chronic administration of exogenous steroids, when given in inhaled or systemic preparations, can lead to adrenal insufficiency (AI). AI is seen in 7.8% of patients receiving chronic inhaled steroids and 48.7% of patients receiving chronic systemic steroids. The administration of steroids in EoE is unique, as patients typically swallow topical preparations of the drug. The risk of secondary AI from taking swallowed topical steroids is currently unknown, as there has been no study in an adult population assessing this risk as a primary endpoint. Pediatric studies of patients with EoE have shown the risk of AI from swallowed topical steroids to be 5-10%. Based on the risk of AI with inhaled steroids (7.8% prevalence) and the prevalence of AI from swallowed topical steroids in pediatric populations (5-10%), we hypothesize that the risk with swallowed topical steroids is >5%. This could warrant consideration of screening given the potentially serious consequences of undiagnosed AI. To address this hypothesis, this project aims to define the prevalence of developing AI in adults with EoE taking swallowed topical steroids and compare that prevalence to a similar control population of adults with EoE who are taking proton pump inhibitors.

Inclusion Criteria:

• 300 adult male or female patients between 18 and 85 years of age with a diagnosis of eosinophilic esophagitis who have been on swallowed topical steroids or proton pump inhibitor therapy (any dosing) for at least 3 months.

Exclusion Criteria:

• We will exclude control patients on proton pump inhibitor therapy if they have used any form of exogenous steroids within the past one year.

Participants will be enrolled during visits at the University of Colorado Anschutz Medical Campus gastroenterology clinic and endoscopy center.