Airway inflammation in atopic patients: a comparison of the upper and lower airways.

OBJECTIVE: The purpose of this study was to understand and assess the inflammatory response within the upper and lower airways in patients suffering from both asthma and allergic rhinitis. Study Design. Cross-sectional study. Setting. A laboratory-based study of patients with allergic rhinitis and asthma.

SUBJECTS AND METHODS: Glycol methacrylate resin-embedded specimens from 10 patients with allergic rhinitis and asthma taken from the nose and bronchi were assessed by immunohistochemistry. Monoclonal antibodies directed against specific cell markers for mast cells (AA1), eosinophils (EG2), neutrophils (NOE), and lymphocytes (CD3(+), CD4(+), CD8(+)) were studied. Cells were counted blind (as cells/mm(2)) in the submucosal matrix. Mann-Whitney U test was used for analyses. P values of .05 or lower were considered statistically significant.

RESULTS: There was a significant increase in CD4(+) (P = .05) and CD8(+) cell counts (P = .001) in the lower airway compared to the upper airway. There were no differences between the 2 groups in the number of neutrophils, mast cells, eosinophils, and the CD3(+) cell counts.

CONCLUSION: The upper and lower airways have parallel inflammation with possible bidirectional extension of inflammation in patients suffering from asthma and allergic rhinitis. There is increased lymphocytic infiltration in the lower airway, suggesting a possible preponderance for development and maintenance of allergic disease in the lower airway.