Atopy patch testing has been used in some cases for the potential identification of delayed, non-IgE (cell-mediated) reactions. Diagnostic criteria
The diagnosis of eosinophilic esophagitis requires all of the following:

Symptoms related to esophageal dysfunction. Eosinophil-predominant inflammation on esophageal biopsy, characteristically consisting of a peak value of ≥15 eosinophils per high power field (HPF). Exclusion of other causes that may be responsible for symptoms and esophageal eosinophilia. Treatment
The goal of EoE treatment is to control the symptoms by decreasing the number of eosinophils in the esophagus and, subsequently, reducing the esophageal inflammation. Management consists of dietary, pharmacological, and endoscopic treatment. Dietary management
Dietary treatment can be effective, as there does appear to be a role of allergy in the development of EOE. Allergy testing is not particularly effective in predicting which foods are driving the disease process. If no specific allergenic food or agent is present, a trial of the six food elimination diet (SFED) can be pursued. Various approaches have been tried, where either six food groups (cows milk, wheat, egg, soy, nuts and fish/seafood), four groups (animal milk, gluten-containing cereals, egg, legumes) or two groups (animal milk and gluten-containing cereals) are excluded for a period of time, usually six weeks. A "top down" (starting with six foods, then reintroducing) approach may be very restrictive. Four- or even two-group exclusion diets may be less difficult to follow and reduce the need for many endoscopies if the response to the limited restriction is good.Alternative options to SFED includes the elemental diet, which is an amino acid based diet.
The eosinophils are recruited into the tissue in response to local production of eotaxin-3 by IL-13 stimulated esophageal epithelial cells. Diagnosis
The diagnosis of EoE is typically made on the combination of symptoms and findings on diagnostic testing. To properly diagnose EoE, various diseases such as GERD, esophageal cancer, achalasia, hypereosinophilic syndrome, infection, Crohns disease, and drug allergies need to be ruled out. Prior to the development of the EE Diagnostic Panel, EoE could only be diagnosed if gastroesophageal reflux did not respond to a six-week trial of twice-a-day high-dose proton-pump inhibitors (PPIs) or if a negative ambulatory pH study ruled out gastroesophageal reflux disease (GERD).Radiologically, the term "ringed esophagus" has been used for the appearance of eosinophilic esophagitis on barium swallow studies to contrast with the appearance of transient transverse folds sometimes seen with esophageal reflux (termed "feline esophagus"). Endoscopy
Endoscopically, ridges, furrows, or rings may be seen in the esophageal wall. Sometimes, multiple rings may occur in the esophagus, leading to the term "corrugated esophagus" or "feline esophagus" due to similarity of the rings to the cat esophagus. Presence of white exudates in esophagus is also suggestive of the diagnosis. On biopsy taken at the time of endoscopy, numerous eosinophils can be seen in the superficial epithelium. A minimum of 15 eosinophils per high-power field are required to make the diagnosis. Eosinophilic inflammation is not limited to the esophagus alone, and does extend through the whole gastrointestinal tract.