[Application of nasal nitric oxide in primary diffuse chronic rhinosinusitis]

Objective:This study aimed to investigate whether nasal nitric oxide（nNO） could be used to identify the main clinical phenotypes of primary diffuse chronic sinusitis（CRS） and reflect the severity of sinus mucosal lesions. Methods:A total of 57 patients with primary diffuse CRS were included as the case group in this study. And the patients were divided into eosinophilic CRS（EosCRS） group and non-EosCRS group according to the percentage of eosinophils in peripheral blood. At the same time, 32 healthy volunteers were selected as the control group. According to whether there is nasal polyps under nasal endoscopy, the EosCRS group was classified into EosCRS with nasal polyps（EosCRSwNP） and EosCRS without nasal polyps（EosCRSsNP）. In the same way, the non-EosCRS group was assigned to non-EosCRS with nasal polyps（non-EosCRSwNP） and non-EosCRS without nasal polyps（non-EosCRSsNP）. The levels of nNO were detected by single nostril air extraction with 10 mL/s flow rate and soft palate closure. The severity of sinus lesions were evaluated by Lund-Mackay score. The difference of nNO levels were compared by the Rank sum test. The correlation between nNO levels and Lund-Mackay score was analyzed by Pearson correlation analysis. Results:①The levels of nNO in EosCRS group [315.00（88.00, 446.50） ×10⁻⁹] and non-EosCRS group [419.00（181.00, 469.00） ×10⁻⁹] were significantly lower than those in the control group [457.00（431.00, 493.75） ×10⁻⁹]（P<0.01）. ②The levels of nNO in EosCRSwNP group [260.00（71.75, 391.50） ×10⁻⁹] were significantly lower than that in EosCRSsNP group [557.00（442.50, 619.75） ×10⁻⁹], and that in non-EosCRSwNP group [210.00（159.75, 434.25） ×10⁻⁹] were significantly lower than non-EosCRSsNP group [455.00（425.00, 481.00） ×10⁻⁹]（P<0.05）. ③There was a medially negative correlation between the levels of nNO and the total score of Lund-Mackay score in the EosCRS group（r=-0.567, P<0.01）. Conclusion:The levels of nNO can be used to determine whether primary diffuse CRS is accompanied by nasal polyps and reflect the severity of nasal sinus mucosal lesions, instead of identifying the main clinical phenotypes of primary diffuse CRS.