Nasal nitric oxide concentration in paranasal sinus inflammatory diseases

In normal upper airways, nitric oxide is generated by the paranasal sinus epithelium and then diffuses into the nasal cavities. This study examined whether or not nasal NO concentration is affected by paranasal sinus inflammatory diseases. The influence of obstruction (nasal polyposis) and/or inflammation (allergy or chronic sinusitis) of the paranasal sinuses on nasal NO concentration was evaluated in nasal allergic (n=7 patients) or nonallergic (n=20) polyposis, nonallergic chronic sinusitis (n=10) and Kartagener's syndrome (n=6) and compared with control subjects (n=42). A score of alteration of the paranasal sinus (number of altered and occluded sinuses) was determined by a computed tomography scan. The nasal NO concentration in nasal nonallergic polyposis (150+/-20 parts per billion (ppb)) was significantly decreased compared with both controls (223+/-6 ppb, p=0.01) and polyposis with allergy (272+/-28 ppb, p<0.0001). In each group, the nasal NO concentration was inversely correlated with the extent of tomodensitometric alteration of the paranasal sinuses. In Kartagener's syndrome, the nasal NO concentration (14+/-2 ppb) was drastically decreased compared with all other groups, despite the presence of open paranasal sinuses. Thus, the nasal NO concentration in patients with nasal polyposis appeared to be dependent on both the allergic status and the degree of obstruction of the paranasal sinuses.