An update on the immunopathogenesis of eosinophilic esophagitis

Abstract

Eosinophilic esophagitis (EoE) is a chronic clinicopathological entity characterized by large numbers of intraepithelial eosinophils infiltrating the esophageal mucosa, which is not caused by gastroesophageal reflux. This disease has become widely recognized over the past few years and new methods have been developed to reveal its underlying pathophysiological mechanisms. Owing to the high prevalence of food and/or airborne allergen sensitization in EoE patients, the allergic nature of the disease had to be defined, which has certain factors in common with other IgE-dependent entities, such as bronchial asthma or allergic rhinitis. Of these, some cytokines and chemokines previously studied in asthma have also been implicated in molecular mechanisms causing eosinophil-rich esophageal inflammation. However, the role played by IgE in relation to the esophageal eosinophilic infiltrate must be clarified, together with the possible function of mast cells in the inflammatory infiltrate and its activation stimuli. A putative role has also been recently suggested for gastroesophageal reflux in the origin of EoE that should be profoundly analyzed, together with the role of specific genes implicated in other digestive inflammatory disorders. This article reviews recent advances in the immunopathogenesis of EoE, which should also consider other pathways to activate the esophageal mucosal immune system.

Treatment of Adult Eosinophilic Esophagitis with Diet

“…Possible explanations for the wide variability in efficacy rates of skin allergy testing-directed food elimination include increasing evidence of a cell-mediated delayed hypersensitivity reaction rather than a predominantly IgE-mediated response as the main pathophysiological mechanism leading to EoE [37]. In fact, food-specific IgE serum measurements and SPTs have proven to be neither sensitive nor specific methods for retrospectively predicting EoE triggers in adult patients [12,13].…”

Adult versus pediatric eosinophilic esophagitis: important differences and similarities for the clinician to understand

“…Fibrous remodeling has been demonstrated in both pediatric [71] and adult EoE patients [56,72]; while it constitutes a reversible phenomenon in the former [59], it tends to persist in the latter [56,72]. In addition to digestive motor disturbances [73], fibrous remodeling also explains the strictures commonly associated with EoE and the obstructive symptoms found in many reported cases.…”

“…The low sensitivity of allergy tests in predicting the causal food agent in the majority of patients who later undergo food reintroduction treatment [78,80] leads us to conclude that IgE-mediated allergies may not be the main pathophysiological mechanism in EoE; instead, a delayed hypersensitivity reaction against common, regularly consumed foods appears to be more likely [73]. Studies based on challenge through sequential reintroduction of single foods with repeated endoscopies and biopsies to identify the offending foods are impractical and have important drawbacks; therefore, the development of non-or minimally invasive markers to replace the need for multiple endoscopies is a top priority.…”

Montelukast Was Inefficient in Maintaining Steroid-Induced Remission in Adult Eosinophilic Esophagitis

“…In fact, it is recognized today as the most common eosinophilic gastrointestinal disease [2]. Eosinophilic esophagitis is considered to be an atopy-associated inflammatory disorder, whose epidemiology has risen in recent years parallel to other immunoallergic diseases [3][4][5].…”