Electron microscopic study of intercellular space: Correlation analysis of bronchial asthma and gastroesophageal reflux disease

Background and Aims: Bronchial asthma (BA) is considered an extra-esophageal syndrome of gastroesophageal reflux disease (GERD) with poor pathophysiological background. We analyzed the correlation between GERD and BA, examining esophageal epithelium with transmission electron microscopy (TEM), along with clinical findings.Methods: BA patients of controlled and partly-controlled levels were enrolled in the study. A pulmonary and gastrointestinal (GI) questionnaire was given. Patients with no symptoms joined the control group. Esophageal mucosal tissue was taken by esophagogastroduodenoscopy from both groups and processed for TEM. Intercellular space (IS) was measured with an image analyzing program, 100 times for each patient.Results: The control (n = 20) and BA (n = 20) groups revealed no significant differences in baseline characteristics. All BA patients were using corticosteroid inhalers, with seven patients having a recent history of acute exacerbation. Patients with at least one GI symptom made up 70% (14/20) of the BA group, and heartburn and/or regurgitation were detected in 40% of patients. Endoscopic findings of GERD were mucosal breaks (n = 3). The IS of the control group was 0.389 ± 0.297 um, while the BA group was 0.806 ± 0.556 um (P = 0.001). The presence of GERD symptoms (P = 0.306) and a history of recent asthma attacks (P = 0.710) did not show significant differences.Conclusions: The BA group showed a significant difference in the dilatation of IS compared to the control group, suggesting a higher prevalence of GERD in BA patients and a close pathophysiological correlation.