A Japanese case series of 12 patients with esophageal eosinophilia.

Background: Eosinophilic esophagitis (EoE) has been a rarely recognized condition in Asian populations, and its clinical manifestation is rarely documented. Our aim was to describe clinically, endoscopically, and pathologically the features of patients with esophageal eosinophilia, including EoE.
Methods: Twelve patients histologically proven to have esophageal eosinophilia were investigated. The histological diagnostic cutoff value was defined as a peak of ≥15 eosinophils/high-power field (HPF) in esophageal biopsies. Symptoms, endoscopic and pathological findings, and treatment outcome were evaluated.
Results: Nine of the 12 patients were male and the 12 patients had a mean age of 47.7 years. Allergic conditions were concurrent in a total of 3 patients. Mild peripheral eosinophilia was observed in only 2 patients. The predominant symptom was solid-food dysphagia, but some patients complained of heartburn, or chest, epigastric, or back pain. Three asymptomatic subjects were also incidentally diagnosed during endoscopic screening. Linear furrows, concentric rings, and white exudates in the esophagus were frequently observed. In 4 of 5 patients who were administered a proton pump inhibitor (PPI), esophageal eosinophilia was histologically decreased or disappeared with symptom relief and endoscopic improvement. In 2 patients unresponsive to PPI, topical steroid therapy, administered by the swallowing of fluticasone propionate, led to symptomatic and histological remission.
Conclusions: The endoscopic recognition of linear furrows, concentric rings, and white exudates is important in the diagnosis of eosinophilic esophageal inflammation. In a subset of patients this condition improves clinicopathologically with PPI treatment, and typical EoE, as strictly defined by unresponsiveness to PPI, appears to be a rather rare condition.