Results of ambulatory pH monitoring do not reliably predict response to therapy in patients with eosinophilic oesophagitis

Abstract

Aliment Pharmacol Ther 2012; 35: #–# Summary Background The consensus statements for eosinophilic oesophagitis recommend that ambulatory pH monitoring is one means of determining if gastro‐oesophageal reflux is the cause of oesophageal eosinophilia and should guide pharmacological therapy. Aim To evaluate prospectively the accuracy of pH monitoring as a predictor of endoscopic, histological and symptomatic response in patients with oesophageal eosinophilia. Methods We conducted a prospective trial in which patients with oesophageal eosinophilic infiltration with ≥15 eos/hpf underwent a 24‐h pH study and were placed in one of two treatment arms for 6 weeks based on positive or negative results. Patients with abnormal acid exposure were treated with esomeprazole 40 mg twice daily and others were treated with oral viscous budesonide 1 g twice daily. Response to treatment was assessed by oesophageal histology (<5 eos/hpf) and symptoms. Results A total of 51 patients were enrolled in the study. The average patient age was 39 years and 31 patients (61%) were male. The average number of eosinophils per hpf, prior to study enrolment was 41.2 (range 15–140, s.d. 27.7). Nineteen (37%) had positive pH studies and 32 (63%) had negative pH studies. Eighteen patients completed treatment with esomeprazole. Only eleven (61%) had histological response and, of these eleven, five (46%) had symptomatic improvement. A total of 28 patients with normal acid exposure completed treatment with budesonide. Only 16 (57%) had histological and 11 (69%) had symptomatic improvement. Conclusion In this prospective trial of pH‐guided treatment, neither positive nor negative results of initial pH monitoring accurately predicted response to therapy.