Eosinophilic (ee-uh-sin-uh-fil-ik) esophagitis (EoE) is an allergic swallowing disorder. EoE affects the esophagus, the part of the gastrointestinal tract (gut) that connects the back of the throat to the stomach. EoE occurs when a type of white blood cell called an eosinophil invades the esophagus. It is often triggered by food. EoE may be triggered by pollen as well. Both children and adults can have EoE.
Eosinophils are a specialized type of white blood cell. Eosinophils help us fight off certain types of infections, such as parasites or hookworms. However, eosinophils also are involved in other conditions, including allergies and other inflammation problems. The eosinophil is a cell that serves many roles. Some roles are specific and some not specific, which means that there are a number of different processes in the body that can cause eosinophils to be present. An eosinophilic disorder may be present when eosinophils are found in high numbers in the blood or part of the body for a long period of time without a known cause. Generally, this means more than 6 months.
Eosinophilic disorders can occur in different areas of the gastrointestinal (GI) tract. For instance, eosinophilic esophagitis (EoE) means abnormal numbers of eosinophils in the esophagus. Eosinophils are not normally present in the esophagus. Eosinophils are normally found in small numbers in other areas of the GI tract.
A variety of triggers may cause this abnormal production and collection of eosinophils. Foods can be one of those triggers in some people in EoE. Other disorders can cause eosinophils in the esophagus and these causes must be considered as well. Some other conditions include:
- Gastroesophageal reflux diseases (GERD)
- Other forms of esophagitis that damage the lining of the esophagus
- Inflammatory bowel disease
Usually, a combination of history and biopsy results is able to lead to the correct diagnosis.
EoE affects people of all ages, genders and ethnic backgrounds. In certain families, there may be an inherited (genetic) tendency.
It is common for people with EoE to have other allergic diseases such as asthma or eczema.
What are the symptoms of EoE?
Symptoms vary from one person to the next. The symptoms often differ depending on age. Symptoms in young children may include refusal to eat, vomiting and poor weight gain. Older children and adults may experience heartburn, chest pain and difficulty swallowing. Although one or more foods are often implicated in triggering EoE, the relationship to particular foods may be difficult to establish. The symptoms can occur days or even weeks after eating a food allergen. However, symptoms may wax and wane, meaning they are not always present. This can be confusing. Common symptoms include, in rough age order:
- Poor appetite
- Failure to thrive (poor growth or weight loss)
- Difficulty sleeping
- Nausea and vomiting
- Abdominal or chest pain
- Reflux that does not respond to usual therapy (this includes proton pump inhibitors, a medicine which stops acid production in the stomach)
- Difficulty swallowing (dysphagia)
- Food impactions (food gets stuck in the throat)
How is EoE diagnosed?
Unfortunately, at this time, EoE cannot be diagnosed by symptoms alone. Symptoms often guide your physician as to when to begin evaluation for EoE. EoE is diagnosed through a test called an upper endoscopy. During an upper endoscopy, a flexible telescope is passed into the esophagus and a small tissue sample, or biopsy, is taken and studied for eosinophils. A specialist called a gastroenterologist performs the endoscopy. The endoscopy is often performed after trying reflux medications to relieve the symptoms. Medications for reflux include proton pump inhibitors (PPI) such as Prevacid.® Another type of reflux medicine is histamine-2 (H2) blockers such as Zantac.®
During an upper endoscopy, the specialist looks at parts of the GI tract – the esophagus, stomach and duodenum. The specialist also takes biopsies from several parts of these areas. A pathologist reviews these tissue samples under the microscope.
When the specialist performs the procedure, the surface of the esophagus may appear very abnormal. It could appear very red and inflamed. It could be very narrowed. It could have multiple white bumpy patches. It might even have a Slinky or accordion-like appearance.
Sometimes, it looks quite normal. However, even if the esophagus appears normal, the biopsies may show EoE. If the number of eosinophils is greater than 15, counted per high power viewing field in the microscope, the diagnosis of EoE is supported.
GERD also causes eosinophils in the esophagus, but typically far fewer than in EoE. Currently, experts have not decided what range of eosinophils definitely indicates severe reflux or a process that may respond best to anti-acid medication, and what range clearly indicates EoE. Unfortunately, no other cell or tissue findings have been identified to help clarify this situation.
The pathologist will also look for tissue injury, swelling and thickening. With EoE, the eosinophils are only present in the esophagus and not found in other areas. Also, other causes of eosinophils must be excluded. After a diagnosis of EoE is made, food and pollen allergy testing is usually recommended. This testing helps to guide treatment as these may be triggers in some individuals
Treatment for EoE
Many children and adults with EoE respond well to changes in the diet, although the necessary changes may be difficult. Not all patients respond to elimination diets. Most experts recommend elimination of all diary products. More extensive elimination diets are helpful for some patients. Food allergy testing may help to determine which foods need to be avoided.
Two types of tests may be applied – prick skin tests (“scratch tests’) and patch tests. There are about15-20 “common” foods that have been implicated in EoE. These are the foods that are first tested. Researchers do not know for sure how likely a negative or positive test indicates that one of these particular foods is a trigger for EoE.
Sometimes, foods that people eat regularly may be triggers, even ones that were never associated with symptoms. This is the difficult part of EoE. In “regular” food allergy, there would be no cause to test someone to a food they eat without symptoms. But with EoE, the case is different. Eosinophilic inflammation can be triggered by a food that causes no apparent symptoms.
If a food is negative on both types of testing, the specialist may recommend that the food be permitted in the diet. Once symptoms are gone and the eosinophil counts have gone away for several weeks or months, foods are added back to the diet, one by one. Many gastroenterologists and allergists recommend repeat endoscopies after the addition of each food.
EoE is a chronic, potentially lifelong condition. With the right treatment plan, however, individuals with this disorder can live full and productive lives.
Adapted from: kidswithfoodallergies