Definition
Primary eosinophilic esophagitis (EoE) is a clinicopathologic entity that is characterized clinically by symptoms related to esophageal dysfunction and histologically by an eosinophil-rich inflammation that is limited to the esophagus. This disease involves both the proximal and distal esophagus.
In 2007, a multidisciplinary group proposed a consensus definition for the diagnosis of EoE based on the typical clinical presentation and pathologic findings in the absence of other known causes of tissue eosinophilia.
This group defined primary EoE as a clinicopathological disease characterized by the following:
Symptoms including, but not restricted to, food impaction and dysphagia in adults and feeding intolerance and gastroesophageal reflux disease (GERD) symptoms in children
Presence of 15 or more eosinophils per high power field (hpf) on esophageal biopsy
Exclusion of other disorders associated with similar clinical, histological, or endoscopic features, especially GERD (use of high-dose proton pump inhibitor [PPI] treatment or normal pH monitoring)
Subsequently, as the understanding of EoE evolved, a phenotypic heterogeneity in disease presentation was observed, such as PPI-responsive esophageal eosinophilia. Furthermore, the practical usefulness of the histological criteria was observed to be limited, as the presence of 15 or more eosinophils/hpf on esophageal biopsy samples could not be validated to successfully discriminate among various causes of esophageal eosinophilia, such as GERD, infections, Crohn disease, and hypersensitivity, among others. All of these factors led to a need to review the 2007 recommendations.
Therefore, in 2011, the multidisciplinary group proposed a new conceptual definition for EoE, according to which “Eosinophilic esophagitis represents a chronic immune/antigen mediated esophageal disease characterized clinically by symptoms related to esophageal dysfunction and histologically by eosinophil-predominant inflammation.”
2013 Guidelines from the American College of Gastroenterology (ACG) define eosinophilic esophagitis as the following
:
The presence of symptoms related to esophageal dysfunction such as dysphagia, food impaction, chest pain, etc
Esophageal mucosa with eosinophil-predominant inflammation, up to 15 eosinophils per high power field
Mucosal eosinophils limited to the esophagus and persist after a trial of PPIs
Exclusion of secondary causes of esophageal eosinophilia