Department of Allergology and Internal Medicine, Medical University of Bialystok, Bialystok, Poland.
Int Arch Allergy Immunol. 2012;159(2):121-9. doi: 10.1159/000335674. Epub 2012 May 30.
Nitrosative and acid stress play an important role in the pathogenesis of asthma. The aim of this study was to evaluate whether, in asthmatics, a link exists between the concentrations of nitrite/nitrate, ammonia and pH values in exhaled breath condensate (EBC) and asthma severity, lung function, exhaled nitric oxide (F(ENO)), total IgE, eosinophil cationic protein (ECP) and blood eosinophilia.
The above-mentioned parameters were measured in 19 healthy volunteers and 91 allergic asthmatics divided into three groups, i.e. 22 subjects with steroid-naïve stable asthma, 35 with inhaled corticosteroid (ICS)-treated stable asthma and 34 with ICS-treated unstable asthma.
Compared with healthy subjects, EBC from asthmatics had significantly lower pH values and ammonia concentrations and significantly higher levels of nitrite/nitrate. The extent of these changes was higher in patients with unstable than in patients with steroid-naïve and stable ICS-treated asthma. The EBC pH was positively correlated with ammonia and negatively correlated with nitrite/nitrate, F(ENO) or blood eosinophilia in all three groups of asthmatics. Significant positive correlations between EBC nitrite/nitrate and blood eosinophilia, ECP levels or F(ENO) were observed in all groups of asthmatics. Significant negative correlations between EBC ammonia and nitrite/nitrate, F(ENO), ECP concentrations or blood eosinophilia were demonstrated in the groups of ICS-naïve and ICS-treated stable asthmatics.
In asthmatic patients there is a relationship between EBC pH, ammonia and nitrite/nitrate concentrations and other recognized markers of airway inflammation. EBC pH values, ammonia and nitrite/nitrate levels measured together may help to assess airway inflammatory status and asthma severity.
硝化和酸应激在哮喘发病机制中起重要作用。本研究旨在评估哮喘患者呼出气冷凝液（EBC）中硝酸盐/亚硝酸盐、氨和 pH 值的浓度与哮喘严重程度、肺功能、呼出气一氧化氮（FENO）、总 IgE、嗜酸性粒细胞阳离子蛋白（ECP）和血嗜酸性粒细胞之间是否存在关联。
在 19 名健康志愿者和 91 名过敏性哮喘患者中测量了上述参数，这些患者分为三组：22 名未接受激素治疗的稳定型哮喘患者、35 名接受吸入性皮质类固醇（ICS）治疗的稳定型哮喘患者和 34 名接受 ICS 治疗的不稳定型哮喘患者。
与健康受试者相比，哮喘患者的 EBC pH 值、氨浓度和硝酸盐/亚硝酸盐水平显著降低。不稳定型哮喘患者的变化程度高于未接受激素治疗和接受 ICS 治疗的稳定型哮喘患者。EBC pH 值与氨呈正相关，与硝酸盐/亚硝酸盐、FENO 或血嗜酸性粒细胞呈负相关，在三组哮喘患者中均如此。在所有三组哮喘患者中，EBC 硝酸盐/亚硝酸盐与血嗜酸性粒细胞、ECP 水平或 FENO 呈显著正相关。在未接受 ICS 治疗和接受 ICS 治疗的稳定型哮喘患者中，EBC 氨与硝酸盐/亚硝酸盐、FENO、ECP 浓度或血嗜酸性粒细胞呈显著负相关。
在哮喘患者中，EBC pH 值、氨和硝酸盐/亚硝酸盐浓度与其他公认的气道炎症标志物之间存在关联。一起测量 EBC pH 值、氨和硝酸盐/亚硝酸盐水平可能有助于评估气道炎症状态和哮喘严重程度。
