Proton-pump inhibitor-responsive esophageal eosinophilia (PPI-REE) is a rare, gastroenterologic disease characterized by typical clinical, endoscopic and histological features of eosinophilic oesophagitis (i.e. symptomatic oesophageal dysfunction associated with eosinophil-predominant mucose infiltrate) which completely remits upon proton pump inhibitor therapy.