Abstract: Objective To investigate the clinical value of nasal nitric oxide(nNO)in the diagnosis of chronic sinusitis(CRS). Methods The clinical characteristics of 135 CRS patients with or without nasal polyps(wNP and sNP, respectively), and 40 non-CRS patients were analyzed. The retrospective analyses included the differences of nNO levels, correlation between nNO and age, body mass index(BMI), peripheral blood eosinophils count and percentage, computed tomography Lund–Mackay score, and the ethmoid sinus/maxillary sinus(E/M)CT ratio. The diagnostic value of nNO in CRS was determined by receiving operating curve(ROC)curve and logistic regression model analyses. Results The level of nNO in CRSsNP and CRSwNP patients was significantly lower than in non-CRS patients(P<0.001). The level of nNO in CRSwNP patients was significantly lower than in CRSsNP patients(P<0.001). The level of nNO in patients with eosinophilic CRSwNP was lower than that in the non-eosinophilic CRSwNP patients(P<0.001). The nNO levels in the CRS and CRSwNP groups were significantly negatively correlated with E/M ratio and Lund-Mackay score(r=-0.423, P<0.001; r=-0.650, P<0.001; r=-0.434, P<0.001; and r=-0.608, P<0.001, respectively). Logistic regression analysis revealed the significant correlation between nNO level and CRS typing(P<0.01). nNO had moderate predictive value in distinguishing non-CRS from CRSsNP and CRSwNP(area under the ROC curve(AUC=0.849,P<0.001; AUC=0.771,P<0.001; AUC=0.894,P<0.001, respectively). nNO also had moderate predictive value in distinguishing CRSsNP from CRSwNP,(AUC=0.776, P<0.01). nNO had moderate predictive value in distinguishing non-CRS from non-eCRSwNP,(AUC=0.861, P<0.001)and high predictive value in distinguishing non-CRS from eCRSwNP(AUC=0.910,P<0.001). Conclusion nNO has clinical value in the preliminary diagnosis of CRS, distinguishing CRSsNP from CRSwNP, predicting eCRSwNP and non-eCRSwNP, and predicting lesions of nasal polyps.

Key words: Sinusitis, Nasal polyps, Nitric oxide, Eosinophils, Allergic