Periostin is highly expressed in the oesophageal epithelium of patients with Eosinophilic Oesophagitis (EoE). We hypothesized that serum periostin levels could be serve to differentiate between EoE and subjects with proton pump inhibitor-responsive oesophageal eosinophilia (PPI-REE).
A cohort study was conducted. Subjects were stratified into two groups: EoE and PIP-REE accorded to recent consensus guidelines. Response to proton pump inhibitors (PIP) was define as achieving less than 15 eosinophils/high-power field from baseline following at least a 8 weeks of PIP treatment (20-40mg twice a day of any of the available agents, prescribed at the discretion of the clinician). Serum periostin were measured by ELISA.
A total of 22 patients were included,12 PIP-REE (mean age 13.5 years, 67% male and 58% have an atopic disorder) and 10 EoE ( mean age 10.9 years, 90% male and 100% have an atopic disorder). Food impaction and abdominal pain were common symptoms in both groups but most common in PIP-REE (67% and 33% vs 20% and 20%). PIP-REE group had a slightly higher median serum periostin level than EoE group (mean 34.93 ng/dl, CI 95% 25.32-43.29, SD 13.69) vs (mean 29.22 ng/dl, CI 95% 26.60-32.82, SD 6.48), but there was no significant difference.
Serum periostin was similar in EoE and PIP-responsive oesophageal eosinophilia in our study. Clinical features are indistinguishable too. More studies are necessary to clarify the differences in both entities and more experience are needed to determinate the role of periostin levels as biomarker for either diagnosis or monitoring of this entities.