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The current prevalence is estimated at 1/2,300-1/1,750 worldwide and appears to be on the increase. It is a predominantly male disorder.

Most cases present in children and young adults, but EoE can occur at any age. Infants and toddlers manifest with food refusal, vomiting, choking with meals and in rare cases, failure to thrive. School-aged children most commonly present with dysphagia, choking/gagging with meals, food impactions and, less commonly, regurgitation, vomiting, and chest/abdominal pain. Adults manifest mainly with dysphagia as well as food avoidance, food impactions and intractable heartburn. Symptoms may be chronic or intermittent, with some patients being completely asymptomatic during long periods. Overall, symptoms may persist up to 4 -5 years before a diagnosis is reached. In 75% of cases, there is a personal or family history of other atopic diseases (i.e. dermatitis, rhinitis, asthma).

Exact etiology is unknown but several theories have been proposed. In approximately 7% of EoE patients, a positive family history is reported (usually in affected siblings) therefore it seems clear that certain inherited genes could increase susceptibility to EoE. However, the environmental and epigenetic factors determining disease onset have yet to be clearly defined. EoE is thought to be associated with T helper cell (Th)-2 type immune responses, as elevated levels of Th 2 cytokines and mast cells have been found in the esophagus of patients.

Diagnosis is based on clinical and endoscopic examination of the esophagus revealing linear furrowing, white speckled exudates, concentric rings, Schatzki ring and linear mucosal tears after introduction of endoscope (but in up to 30% of cases the esophagus appears normal). An esophageal mucosal biopsy is essential in the diagnosis of EoE and is based on the presence of at least 15 eosinophils/high power field (HPF), irrespective of the results of pH-monitoring. A diagnosis of EoE can be established after documenting the persistence of a pathological eosinophilic infiltration following an 8-week double dose trial of PPIs.

Differential diagnoses include gastroesophageal reflux disease (GERD), severe small-calibre esophagus and esophageal candidiasis. PPI responsive esophageal eosinophilia, currently indistinguishable from EoE before a PPI trial, should be also excluded.

Treatments include dietary management, pharmacologic therapy and mechanical dilation of the esophagus. The empiric 6-food elimination diet, targeted dietary restrictions and sometimes the elemental diet can help identify any possible food allergies. Continuous avoidance of food allergens triggering EoE maintains disease remission for years, often with no need of medication. Topical corticosteroids are the most common choice of medication. Thiopurinic immunosuppressants may be useful in those with dependence or refractoriness to steroids. Leukotriene receptor antagonist and mast cell stabilizers are not recommended. Maintenance therapy should be considered to avoid recurrence. Endoscopic dilation is reserved for those with persistent symptomatic strictures, and provides symptom improvement in the majority of cases, at least in the short term.

EoE is a chronic disorder with persistence of symptoms and inflammation over years. Both steroids and dietary modification can provide temporary relief but the impact of continuous food avoidance or drug use on sustained remission and on quality of life has not yet been evaluated.