Histopathologic Variability in Post Proton Pump Inhibitor (PPI) Trial Biopsies of 31 Patients with Initial Clinicopathological Features Diagnostic of Eosinophilic Esophagitis (EoE)
MC Wang, B Zhu, E Toto, I Hirano, ZE Chen. Northwestern University Feinberg School of Medicine, Chicago, IL
Background: Distinguishing EoE from gastroesophageal reflux disease (GERD) can be challenging due to significant overlap in clinical, endoscopic, and histopathologic features between the two entities. To facilitate the distinction, a clinical trial of PPI therapy has been recommended. However, analysis of the histopathologic features and their clinical correlates in post-trial biopsies has not been well documented.
Design: 31 patients (24 male and 7 female, mean age of 36) with clinicopathologic features of EoE who had received a PPI clinical trial (double dose, 2 months) were identified. The average interval between pre- and post-trial endoscopic biopsies was 3 months. Clinical presentation and endoscopic findings were reviewed. The histopathologic features of all specimens were analyzed according to the recommended criteria. The data were compared and statistically analyzed via student t-test and Fisher's exact test.
Results: All pre-trial biopsies showed histologic features compatible with EoE (average maximum eosinophil count (MEC) = 36+8.5). Post-trial biopsies showed variable results (average MEC = 5.5+0.7, p<0.05). Eight (25%) patients showed normal histology and reported symptomatic improvement. Ten (32%) patients continued to show histologic features of EoE. Seven (70%) of these patients reported symptomatic improvement, with 2 (20%) also showing endoscopic improvement, despite no difference between the pre- and post-trial MECs (52.5 vs. 60, p>0.05). The remaining 13 patients showed abnormal histologic features but failed to meet the diagnostic criteria for EoE. The pre- and post-trial MECs (36 vs. 5.5; p<0.05) were statistically different in this group, and at least 9 (60%) patients reported symptomatic improvement, with 6 (46%) also showing endoscopic improvement.
Conclusions: Our data reveal marked histopathologic variability in the post-trial biopsies of patients with initial clinicopathologic features diagnostic of EoE. The results stress the extremely complex relationship between EoE and GERD and further suggest that even PPI trials may be inadequate in distinguishing between them. The current lack of a standardized approach for interpreting these complex post-trial results can cause potential confusion among patients and clinicians.
Monday, March 22, 2010 8:00 AM
Platform Session: Section E, Monday Morning