Subjects with allergic rhinitis show signs of more severely impaired paranasal sinus functioning during viral colds than nonallergic subjects.

Background: Viral cold is thought to be the major contributing factor in the pathogenesis of sinusitis, as it causes ostiomeatal obstruction. The aim was to evaluate whether paranasal sinus functioning during viral colds is similar in subjects with and without allergic rhinitis.
Methods: Forty-eight volunteers were examined during an early (2-4 days) natural cold and again 3 weeks later. The examinations included computed tomography (CT) scans, nasal mucosal biopsies, and viral and bacterial specimens. Subjects with positive skin prick tests and persistent or intermittent rhinitis were considered to have allergic immunoglobulin E (IgE)-mediated rhinitis. In addition, specific IgE antibodies to staphylococcal enterotoxin B (SEB) were measured.
Results: Nine subjects (19%) had allergic rhinitis. The allergic subjects were significantly more often IgE sensitized to SEB than the nonallergic subjects (33%vs 3%, P = 0.02). Viral etiology of the cold was identified in 32 (67%) subjects. The subjects with allergic rhinitis had significantly higher CT scores compared with nonallergic subjects during the colds (median (range) scores 16 (6-22) vs 6 (0-17), P = 0.004). In both groups, the median scores declined markedly during convalescence, but the difference remained significant (P = 0.009). Among the allergic subjects, those who were IgE sensitized to SEB tended to have the highest CT scores [median (range) 16 (16-22)]. Total serum IgE and the nasal subepithelial eosinophil counts correlated with the CT scores during the cold (rs = 0.38, P = 0.008 and rs = 0.46, P = 0.001, respectively).
Conclusions: Subjects with allergic IgE-mediated rhinitis had more severe paranasal sinus changes in CT scans than nonallergic subjects during viral colds. These changes indicate impaired sinus functioning and may increase the risk of bacterial sinusitis.