[Clinical application of a novel quantum dot immunofluorescence method for rapid detection of IgE in nasal secretions in the diagnosis of allergic rhinitis].

Objective:This study aims to evaluate the clinical utility of total IgE （tIgE） and specific IgE （sIgE） levels in nasal secretions for diagnosing allergic rhinitis. The investigation is enhanced through an improved method of nasal secretion collection and advanced quantum dot immunofluorescence detection technology. Methods:A total of 88 subjects were enrolled in this study, and demographic data and clinical characteristics were collected through standardized questionnaires. Anterior rhinoscope was used to check the local condition of the nasal cavity. Each participant underwent skin prick test（SPT）. The total IgE（tIgE） and sIgE in nasal secretions were quantitatively analyzed by improved nasal secretion collection strategy and quantum dot immunofluorescence method, and the correlation between them and clinical symptoms and signs was discussed. The receiver operating characteristic curve（ROC） was used to calculate the optimum threshold and detection efficiency of total IgE and sIgE in nasal secretions. Results:The improved method successfully collected nasal secretions from all subjects. Based on SPT results, participants were categorized into three groups: normal control （20 cases）, non-allergic rhinitis （22 cases）, and allergic rhinitis （46 cases）. Analysis showed that both tIgE and sIgE levels in nasal secretions correlated with nasal symptoms and signs. A tIgE level of ≥9.42 IU/mL was identified as a cut-off for allergic rhinitis diagnosis, demonstrating an 85.37% agreement with SPT results. Furthermore, cut-off values for house dust mite sIgE （≥0.34 IU/mL） and dermatophagoides Farinae sIgE （≥0.41 IU/mL） yielded a diagnostic agreement of 97.56% with SPT. Notably, two patients in the non-allergic rhinitis group tested negative for SPT but positive for dust mite sIgE in nasal secretions and exhibited positive results in the nasal provocation test, indicating potential local allergic rhinitis. Conclusion:The assessment of tIgE and mite-specific IgE levels in nasal secretions presents a rapid, reliable, and non-invasive approach for diagnosing allergic rhinitis, particularly in cases of local allergic rhinitis.