What is EoE?
Eosinophilic esophagitis (EoE) is a relatively newly recognized disease that over the past decade has been increasingly diagnosed in children and adults. This increase is thought to reflect an increase in diagnosis as well as a true increase in EoE cases. Fortunately, the medical community is responding and new scientific information is emerging to guide management of this disorder, which often persists with ongoing or recurrent symptoms.
Eosinophilic esophagitis is characterized by a large number of eosinophils (an active allergy white blood cell) and inflammation in the esophagus (the tube connecting the mouth to the stomach). People with EoE commonly have other allergic diseases such as rhinitis, asthma, and/or eczema. EoE affects people of all ages and ethnic backgrounds. Males are more commonly affected than females. In certain families, there may be an inherited (genetic) tendency.
In individuals with EoE, the eosinophils cause injury to the tissue in the esophagus. EoE can be driven by food allergy or intolerance: most patients who eliminate food proteins from their diet (by drinking only an amino-acid based formula) improve.
Eosinophils are not normally present in the esophagus, although they may be found in small numbers in other areas of the gastrointestinal tract. Diseases other than EoE can cause eosinophils in the esophagus including gastroesophageal reflux diseases (GERD), drug hypersensitivity response, and inflammatory bowel disease (Crohn’s).
What are the symptoms of EoE?
Symptoms vary among individuals and age groups. Vomiting may occur more commonly in young children and difficulty swallowing in older individuals.
Common symptoms include:
- Reflux that does not respond to usual therapy (medicines which stop acid production in the stomach)
- Dysphagia (difficulty swallowing)
- Food impactions (food gets stuck in the esophagus)
- Nausea and Vomiting
- Failure to thrive (poor growth, malnutrition, or weight loss)
- Abdominal or chest pain
- Feeding refusal/intolerance or Poor appetite
- Difficulty sleeping
How is EoE diagnosed?
At present, the only way to definitively diagnose EoE is through endoscopy with biopsies. The endoscopy is often performed after treatment with reflux medications (acid suppressors) have failed to relieve the symptoms. During an upper endoscopy, the gastroenterologist looks at the esophagus, stomach, and duodenum (first part of the small bowel) through an endoscope (small tube inserted through the mouth) and takes multiple biopsies (small tissue samples) which a pathologist reviews under the microscope.
The gastroenterologist may be able to see a problem through the endoscope, but eosinophilic esophagitis may be present even if the esophagus looks normal to the doctor. That is why the biopsy samples are important to making the diagnosis of EoE. A high number of eosinophils (> 15 per high power field) suggest the diagnosis of EoE. GERD also causes eosinophils in the esophagus, but typically far fewer and only in the part of the esophagus closest to the stomach. The pathologist will also look for tissue injury, inflammation, and thickening of the esophageal layers. With EoE, the increased eosinophils are limited to the esophagus and not found in other areas of the intestinal tract. Once the diagnosis of EoE is confirmed, food allergy testing is typically recommended to guide treatment. Skin prick testing to different foods is the most common type of allergy testing.
At present, the two main treatments recommended are dietary management and topical corticosteroids. A comprehensive allergic evaluation to foods and aeroallergens is recommended in the 2007 Consensus Recommendations for Diagnosis and Treatment. In addition food allergy patch testing may be done for additional information.
Most children and adults with EE respond favorably to dietary treatments. Dietary treatment may include:
- Elimination diets, in which all ‘positive’ foods on allergy testing are removed from the diet, may be the only treatment needed for some individuals with eosinophilic esophagitis.
- Six-food elimination diet is another type of elimination diet that has shown success in some EoE patients. Instead of basing dietary elimination on skin testing, patients eliminate the top 6 most allergenic foods (diary, eggs, wheat, soy, peanuts/other nuts, fish/shellfish).
- Elemental diets, in which all sources of protein are removed from the diet, are another dietary therapy. An elemental diet includes only an amino acid formula (building blocks of protein), no whole or partial proteins. Simple sugars, salt and oils are permitted on an elemental diet. Because these formulas are not palatable, the use of a strict elemental diet may require a feeding tube. Amino-acid based formulas are very expensive and are only sometimes covered by health insurance. Elemental diets are effective in treating most children with EoE.
- Food trials involve adding back one ingredient at a time to one’s diet to determine specific foods causing a reaction. Food trials begin after symptoms resolve and eosinophils have cleared. Food trials are handled differently by different professionals, but may involve repeat endoscopies with biopsies as foods are introduced to determine which foods are ‘safe’ for an individual.
Medications for EoE most commonly include steroids to control inflammation and suppress the eosinophils. Steroids can be taken orally or topically (swallowed asthma medicine). For many patients, topical corticosteroids (fluticasone, budesonide) have led to EoE remission (improvement while on treatment), though their long-term use for maintenance treatment has not been studied. Acid suppressors may also help symptoms in some patients with reflux.
EoE requires ongoing care
Patients with EoE may require additional endoscopies to assess how the esophagus is responding to specific treatment. Physicians and scientists are working to discover other methods of monitoring and diagnosis. Novel medicines are also being tested that may help with future management of EoE.
EoE does not appear to limit life expectancy and there is currently no data suggesting EoE causes cancer of the esophagus. In some patients, EoE is complicated by the development of esophageal narrowing (strictures) which may cause food to lodge in the esophagus (impaction). It is not clear how long EoE has to exist before strictures form. However, since the natural history of EE is only emerging, careful monitoring and long-term follow-up is advised. The initial diagnosis of EoE can be overwhelming and often affects the entire family. A positive attitude and a focus on nonfood activities go a long way in learning to live with EoE. With proper treatment, individuals with EoE can lead a normal life.
American Partnership for Eosinophilic Disorders (APFED) is a non-profit organization dedicated to patients and their families coping with eosinophilic disorders. For more information on eosinophilic disorders visit www.apfed.org.