Eosinophilic Esophagitis
| What is allergic esophagus and eosinophilic esophagitis? |
| Allergic esophagus is the lay term for a condition known as eosinophilic esophagitis, abbreviated EE or EoE. It is characterized by inflammation of the esophagus or feeding tube resulting from a type of white blood cell called the eosinophil. This reddish appearing cell is typically found in tissues of the body affected by allergic reactions and parasite infections. The cell was named by Paul Erlich in 1879 after Eos, the Greek goddess of dawn. When activated eosinophils release chemicals like histamine that can cause intense swelling, itching, and damage tissues. |
| What are the symptoms of eosinophilic esophagitis in adults? |
| In adults eosinophilic esophagitis usually causes intermittent episodes of food sticking. Food sticking or hanging up after swallowing is called dysphagia. In classic eosinophilic esophagitis a young man or teenage boy presents with episodes of food being lodged or stuck in the esophagus or feeding tube. Food that won’t go down and can’t be regurgitated up in the background of a history of difficulty swallowing foods such as bread or dry meats like chicken and beef is a common history. When associated with a personal and/or family history of allergic conditions eosinophilic esophagitis is highly likely. |
| How does eosinophilic esophagitis present in children? |
| Young children with eosinophilic esophagitis may present with complaints of chest pain, abdominal pain, poor appetite, regurgitation or reflux, vomiting, or failure to grow (failure to thrive) normally. Some may have unexplained low blood counts or iron deficiency from bleeding from the esophagus. |
| How is eosinophilic or allergic esophagitis diagnosed? |
| It is suspected by the classic history and the appearance of the esophagus on endoscopy. Eosinophilic esophagitis typically results in the esophagus having multiple rings or constrictions that result in the appearance of a cat’s esophagus. This is called felinization of the esophagus or ringed esophagus. Other visual signs may be whitish spots, long furrows or a lining that looks like crepe paper and is very easily torn. |
| What are the diagnostic microscopic criteria for eosinophilic esophagitis? |
| The definitive diagnosis is made by the finding of abnormal numbers of eosinophils in esophageal biopsy tissue. The esophagus normally contains no eosinophils. The number of eosinophils considered abnormal is debated. However, between >15-25 eosinophils per high power field (400x) is considered abnormal with most authorities agreeing that >20 eosinophils is diagnostic. It has been long accepted that chronic acid reflux is commonly associated with 5-10 eosinophils per high power field. However, these eosinophils should be found only in the lower esophagus. Finding eosinophils higher in the esophagus greatly increases the likelihood that eosinophilic esophagitis is present. |
| Why is it important to distinguish eosinophilic esophagitis from acid reflux esophagitis? |
| Acid reflux esophagitis usually responds to acid blocker medications like histamine 2 blockers ranitidine (Zantac), cimetidine (Tagamet), famotidine (Pepcid) and proton pump inhibitors like omeprazole (Prilosec) or esomeprazole (Nexium). However, though symptoms like heartburn associated with eosinophilic esophagitis may improve with these medications, the swallowing difficulties and chest pain do not. |
| How are the swallowing difficulties different in reflux and eosinophilic esophagitis? |
| Acid reflux injury to the esophagus often results in narrowing or constriction of the lower esophagus that causes a food- sticking sensation. Esophageal strictures due to acid reflux are treated by a procedure known as esophageal dilation to stretch the constriction to allow normal swallowing. In the setting of acid reflux, esophageal dilation is usually safe and highly effective. Eosinophilic esophagitis usually results in swallowing difficulties. However, the constrictions of the esophagus that occur in eosinophilic esophagitis are usually multiple rings located higher in the esophagus. Because they are due to injury to the esophagus from the release of allergic chemicals these rings carry a high risk of tearing the esophagus if dilation is attempted before treatment with steroids. |
| Is eosinophilic esophagitis associated with an increase risk of esophageal cancer? |
| There does not seem to be an association of cancer of the esophagus with eosinophilic esophagitis like there is with chronic acid reflux. However, eosinophilic esophagitis can be chronic and difficult to treat. |
| How is eosinophilic esophagitis treated? |
| Identification and elimination of problem allergy foods is the mainstay of treatment. Foods that are associated with positive allergy blood tests or skin tests are eliminated. In some people a strict elimination diet is required. Rarely, a diet of only basic amino acid proteins in a liquid (elemental diet) is required. Temporary relief can be achieved with steroids. Systemic (oral prednisone) works but has the potential side effects of steroids on the rest of the body. Topical steroids, steroid applied directly to the surface that has little or no absorption into the blood stream is preferable. The nasal steroid, fluticasone propionate, has been used successfully. It is sprayed in the mouth and swallowed twice daily. The mouth should be rinsed out followed by spitting out rather than swallowing the water. No eating or drinking for 30 minutes is recommended. A few studies have reported response to mast cell stabilizer disodium cromoglycate (Cromolyn), leukotriene inhibitor montelukast (Singulair), immunomodulators such as aziothioprine (Imuran), or monoclonal antibody against IL-5 mepolizumab. |
| What role do food allergies play in the treatment of eosinophilic esophagitis? |
| Food allergy plays a major role in the cause and treatment of eosinophilic esophagitis, hence the alternative term used, allergic esophagitis. Most patients with eosinophilic esophagitis will be found to have one more food allergies when adequate testing is done. Skin prick allergy testing or blood tests (RAST, IgE food antibodies) can be negative but patch skin testing or intradermal testing may be positive. Sometimes, a strict elimination diet with re-challenge is the only way to implicate a problem food. In most patients a personal and family history of allergic disorders (atopy) such as allergic rhinitis (hayfever), asthma, eczema, atopic dermatitis, or food allergies is present. |
| What are the most problem common foods associated with eosinophilic esophagitis? |
| In descending order, the most common foods reported in the largest series are milk, egg, soy, corn, wheat, beef, chicken, potato, oats, peanuts, turkey, barley, pork, rice, green beans, apples, and pineapple. |
| What is the role of elimination diet in eosinophilic esophagitis? |
| Elimination diet is the most effective treatment in eosinophilic esophagitis. However, elimination diets are difficult to follow for both adults and children and strict elimination diets are very difficult if not impossible to follow long term. Recently, Kagalwalla et al. published their success with a six-food elimination diet (SFED). The SFED restricts foods from six of the most common food allergen categories. The SFED eliminates cow’s milk protein (casein), soy, wheat, egg, peanut/tree nuts, and seafood. When compared with an elemental diet (ELED) the SFED is not quite as effective (74% versus 88% achieving significant improvement) but has better acceptance, cost and likelihood of compliance. Processed foods containing any known or suspected foods must also be eliminated during an elimination diet. |
