The outcome of patients with oesophageal eosinophilic infiltration after an eight-week trial of a proton pump inhibitor

Background Current diagnostic guidelines recommend that eosinophilic oesophagitis (EoE) should be diagnosed only after GERD is excluded by a lack of response to a trial of acid suppression. There is limited information available providing outcome data about the effectiveness of this approach. Aim To examine the impact of double-dose proton pump inhibitor (PPI) therapy on symptoms, endoscopic and histological features in patients with documented oesophageal eosinophilia consistent with EoE (≥15 eosinophils/high-power field). Methods Sixty consecutive symptomatic patients with documented oesophageal eosinophilia received open-label omeprazole 20 mg orally twice daily before meals for 8 weeks. Clinical, endoscopic and histological (resolution: 0-5 eosinophils/HPF, partial improvement: 5-14 eosinophils/HPF), or no improvement: (≥15 eosinophils/HPF) evaluation was repeated at the end of this period. An expert GI pathologist, unaware of the study aims, reviewed all slides. Results Clinical improvement occurred in 43 (71.6%), endoscopic signs were reduced in 34 (61.8%) and normalised in 12 (21.8%), and histologically, 34 (56.6%) improved, while 15 (25%) obtained complete resolution. Overall, 22 patients (36.7%) obtained both complete clinical and histological remission. Conclusions More than 50% of patients with documented oesophageal eosinophilic infiltration in the EoE range improved when treated with a double-dose PPI trial for 8 weeks. These findings support the published guidelines recommending a PPI trial prior to diagnosing EoE, and confirm the existence of an eosinophilic oesophageal infiltrationPPI-responsive population.