Figure 4. Molecular and histological diagnosis of EE.
Patients with PPI refractory upper gastrointestinal symptoms undergo endoscopic biopsy. Tissue is analyzed microscopically and a minimal level of 15 peak eosinophils per hpf is required for diagnosis. In addition, molecular profiling reveals dysregulated expression of 1% of the human genome including eotaxin-3 overexpression that readily distinguishes biopsies from EE, reflux esophagitis (RE) and normal individuals (NL). Following treatment (Rx) with dietary modification and/or glucocorticoids, endoscopic analysis reveals complete resolution of esophageal eosinophilia and large normalization of the EE transcriptome. Residual abnormal gene expression (*) differentiates treated EE from NL and esophagitis RE patients.