Nasal and exhaled nitric oxide in chronic rhinosinusitis with polyps

Background: The ciliary epithelial cells in the paranasal sinuses produce nasal nitric oxide (NO) continuously and plays a variety of roles in the paranasal sinuses. The purpose of this study was to assess whether we can use the levels of nasal NO (nNO) and exhaled NO (eNO) as a tool for evaluation in chronic rhinosinusitis (CRS) with nasal polyp patients. Methods: We used chemiluminescent NO analyzer to measure nNO and eNO among normal controls (32) and CRS with polyp (30) and CRS with polyp and allergic rhinitis patients (27) and compared it with various clinical symptoms, laboratory data, and computed tomography (CT) scores. Results: Levels of nNO were significantly lower in patients with CRS with polyps (88.5 +/- 54.7 ppb) compared with controls (241.0 +/- 89.5 ppb). Levels of nNO in CRS with polyps and allergic rhinitis (167.0 +/- 47.6 ppb) were significantly higher than CRS with polyps and lower than controls. A significant inverse relationship was observed between nNO and sinus CT scores, severity of nasal obstruction, and purulent rhinorrhea in CRS with polyps. Low values of nNO separated well patients with CRS with polyps, and the cutoff value of < 163 ppb was associated with the best combination of specificity (93%) and sensitivity (81%). A significant positive relationship was observed between eNO and CT scores. Conclusion: The nNO could be used for another screening of CRS with polyps for the more severe phenotypes, which may eventually have to be treated with surgery.