Chapter 14. Eosinophilic Esophagitis

• In adults, a major symptom is recurrent dysphagia, often with food impaction; mean duration of symptoms before treatment is 4–6 years.
• Esophageal biopsy shows dense eosinophilic infiltration (≥20 eosinophils per high power field [HPF]).
• Full diagnostic criteria are (1) clinical symptoms of esophageal dysfunction; (2) increased eosinophils in esophageal mucosal biopsies; (3) lack of sustained response to high-dose proton pump inhibition treatment or normal pH monitoring of the distal esophagus.

Eosinophilic esophagitis is a chronic and increasingly recognized inflammatory disorder of the esophagitis characterized by abnormal infiltration of eosinophils of the esophageal mucosa, often resulting in dysphagia and food impaction. The disorder is being diagnosed with much greater frequency, and increased recognition, by virtue of increased endoscopic volume, alone may not be responsible for this trend. Studies have indicated that the incidence has increased more than fourfold in the last 5–10 years. More than 80% of patients diagnosed with eosinophilic esophagitis complain of dysphagia, and between 5% and 16% of patients undergoing endoscopic evaluation for dysphagia are found to have eosinophilic esophagitis. Further, more than 50% of patients presenting with frank food impaction are diagnosed with eosinophilic esophagitis. By contrast, in children and adolescents, gastroesophageal reflux disease (GERD) and esophageal reflux symptoms are as common as food impaction and dysphagia.

The pathogenesis of eosinophilic esophagitis is incompletely defined. However, considerable evidence suggests that eosinophilic esophagitis is an allergic disorder induced by antigen sensitization either through foods and/or aeroallergens.

A majority of patients have evidence of food allergies and a concurrent history of respiratory allergies. A seasonal variation has been documented in the diagnosis of eosinophilic esophagitis that correlated with pollen counts. By contrast, food anaphylaxis is uncommon, occurring in less than 15% of pediatric patients with eosinophilic esophagitis.

The recruitment of eosinophils occurs in several inflammatory or infectious conditions and after exposure to inhaled or ingested allergens. Eosinophils also release chemoattractants, such as interleukins, which can perpetuate an inflammatory response. The latter phenomenon has led to trials of leukotriene inhibitors in the treatment of eosinophilic esophagitis.

Symptoms and Signs

The leading symptom in adults is recurrent attacks of dysphagia. Mean duration of symptoms before diagnosis and initiation of treatment in one large series was 4.6 years. Recurrent dysphagia is present in the majority of patients, as is the history of food impaction. A personal history of allergic diseases (ie, airway allergies, food allergies, or skin allergies) is frequently present. Serum immunoglobulin E (IgE) elevations have been documented in one series in two thirds of the patients. However, it should be emphasized that there is no difference in symptoms, endoscopic findings, or histology in patients with increased serum IgE levels versus those with normal IgE levels. Symptoms appear to be more pronounced in patients with peripheral blood eosinophilia. Another clinical ...