[Pathomorphological criteria and features of immune response in eosinophilic esophagitis and reflux esophagitis]

Eosinophilic esophagitis (EoE) is an immune-mediated disease, manifested by dysphagia and characterized by intraepithelial infiltration: more than 15 eosinophils per field of view at x400 magnification, and requiring differential diagnosis with reflux esophagitis (RE).

To access the implication of EoE histologic scoring system (EoEHSS) for differential diagnosis of EoE and RE and to characterize features of immune response in these diseases.

38 patients with EoE and 38 patients with RE were enrolled in the study. All the patients had esophagogastroduodenoscopy with biopsy. Biopsy specimens were stained with H&E and combined PAS/Alcian blue staining. Immunohistochemical evaluation was conducted with antibodies to CD3, CD4, CD8, CD20, CD56 and CD68.

Grade score of EoEHSS in EoE was 2.4 times more than in RE (p<0.05). Stage score in EoE was 2.75 more than in RE (p<0.05). Intraepithelial count of CD3+ T-lymphocytes comprised 87 (76-95.5) in high-power view in EoE and 45 (38.5-48.5) in high-power view in RE. Intraepithelial count of CD4+ T-lymphocytes was 35 (28-41.5) in high-power view in EoE and 19 (16.5- 22.5) in high-power view in RE. Intraepithelial count of CD8+ T-lymphocytes comprised 59 (50.5-67.5) in high-power field in EoE and 27 (24-28.5) in high-power field in RE.

The use of the EoEHSS histological rating scale for eosinophilic esophagitis is effective in the differential diagnosis of EoE and EC. Predominant cells in intraepithelial infiltrate are CD3+ T-lymphocytes both in EoE and RE, CD8+ cells prevail over CD4+ cells. In EoE intraepithelial count of CD3+ T-lymphocytes is 1.93 times more, count of intraepithelial CD4+ lymphocytes is 1.84 times more and count of CD8+ lymphocytes is 2.19 times more than in RE.