Eosinophilic esophagitis (EoE) is a chronic immune-mediated disorder of the esophagus characterized by eosinophilic inflammation. It typically presents with symptoms of dysphagia, food impaction, and gastroesophageal reflux disease (GERD) that are unresponsive to proton pump inhibitors (PPIs). The condition was first described in the early 1990s, and since then, there has been a growing recognition of its prevalence and clinical significance.
EoE primarily affects children and young adults, although cases in older adults are increasingly being recognized. The exact cause of EoE remains unclear, but it is believed to involve a complex interplay between genetic predisposition, environmental factors, and immune dysregulation. There is evidence to suggest that EoE has a strong familial association, with a higher prevalence observed in individuals with a family history of atopic diseases such as asthma, allergic rhinitis, and eczema.
One of the hallmark features of EoE is the presence of eosinophilic inflammation in the esophageal mucosa. Eosinophils are a type of white blood cell that plays a crucial role in the immune response against parasitic infections and allergic reactions. In EoE, eosinophils infiltrate the esophageal epithelium, leading to tissue damage, fibrosis, and remodeling over time. This chronic inflammation can result in narrowing of the esophageal lumen, leading to symptoms of dysphagia and food impaction.
The clinical presentation of EoE can vary depending on the age of the patient and the severity of the disease. In children, symptoms may include feeding difficulties, failure to thrive, vomiting, abdominal pain, and reflux-like symptoms. In adults, dysphagia, food impaction, and chest pain are more commonly reported. Some patients may also experience symptoms of GERD, such as heartburn and regurgitation, although these symptoms may not respond to standard PPI therapy.
Diagnosis of EoE requires a combination of clinical, endoscopic, and histologic findings. Endoscopy typically reveals characteristic features such as esophageal rings, furrows, and white plaques, although these findings may be absent in some cases. Histologic examination of esophageal biopsies is essential for confirming the diagnosis, with the presence of greater than 15 eosinophils per high-power field (eos/hpf) considered diagnostic of EoE. Other histologic features may include basal zone hyperplasia, eosinophilic microabscesses, and lamina propria fibrosis.
Treatment of EoE aims to alleviate symptoms, reduce eosinophilic inflammation, and prevent complications such as esophageal strictures and food impaction. Dietary management plays a central role in the management of EoE, with the identification and elimination of trigger foods being the cornerstone of therapy. The most common dietary approach involves the use of elimination diets, where potentially allergenic foods such as milk, wheat, soy, egg, and nuts are removed from the diet and then systematically reintroduced to identify trigger foods.
In addition to dietary therapy, pharmacologic interventions may also be used to treat EoE. Topical corticosteroids, such as fluticasone and budesonide, are the most widely studied and effective medications for inducing remission in EoE. These medications are typically administered via a swallowed aerosolized formulation, which is then swallowed to deliver the drug directly to the esophageal mucosa. Systemic corticosteroids may be used in severe cases or when topical therapy is ineffective, although long-term use is generally avoided due to the risk of adverse effects.
In recent years, there has been growing interest in the development of targeted biologic therapies for EoE. These medications, which include monoclonal antibodies targeting specific inflammatory pathways, have shown promise in clinical trials for their ability to reduce eosinophilic inflammation and improve symptoms in patients with EoE. However, further research is needed to determine their long-term efficacy and safety.
The management of EoE requires a multidisciplinary approach involving gastroenterologists, allergists, dietitians, and other healthcare professionals. Long-term monitoring is essential to assess treatment response, monitor for disease progression, and address any complications such as esophageal strictures or Barrett’s esophagus. Despite advances in our understanding and management of EoE, many unanswered questions remain regarding its pathogenesis, natural history, and optimal treatment strategies. Further research is needed to address these knowledge gaps and improve outcomes for patients with this challenging condition.
