Immunological role of nasal staphylococcus aureus carriage in patients with persistent allergic rhinitis.

Nasal carriage of staphylococcus aureus (S.aureus) exerts immunomodulatory effect in patients with atopic dermatitis and it may contribute to airway inflammation and allergic response in patients with allergic rhinitis. We Aim to investigate the frequency of nasal S.aureus carriage in patients with persistent allergic rhinitis and its possible influence on their symptoms and immune markers. We chosed 20 non smoker patients with house dust mite (HDM) allergy causing allergic rhinitis and 20 non smoker healthy subjects matched for age and sex. For all subjects rhinoscopy was done, skin prick test, nasal culture for S.aureus, nasal interleukin 4,nasal total IgE, serum total IgE and serum specific IgE(SSIgE) for HDM. Nasal S.aureus was detected in 16/20 patients (80%) and 5/20 (25%) in healthy subjects with highly significant statistical difference p<0.01. Correlation of nasal staph.aureus count and different systemic and local immune markers revealed highly significant positive correlation between nasal S.aureus count and serum total IgE (r = 0.78, p<0.01) and significant positive correlation with SSIgE (HDM) (r = 0.53, p<0.05), nasal total IgE (r = 0.39, p<0.05) and nasal IL-4 (r = 0.55, p<0.05). Nasal staph.aureus actively modulated the immune reaction in persistent allergic rhinitis patients by promoting local IgE production, so we recommend early detection and treatment of S.aureus carriage in patients.