Zietkowski Z, Bodzenta-Lukaszyk A, Tomasiak M M, Skiepko R, Szmitkowski M
Department of Allergology and Internal Diseases, Medical University of Bialystok, Bialystok, Poland.
J Investig Allergol Clin Immunol. 2006;16(4):239-46.
Nitric oxide (NO) is a molecule with potent biological activity that plays an important role in the physiology of the respiratory system. Increased expression of inducible nitric oxide synthase (iNOS) and elevated fractional concentration of exhaled nitric oxide (F(ENO)) are seen in asthmatic patients. Measurement of F(ENO) has become increasingly recognized for use in the evaluation of bronchial inflammation during monitoring of antiinflammatory treatment.
The aim of this study was to evaluate F(ENO) in a group of steroid-naive asthmatics and assess the relationship of this parameter with the results of other tests used in the diagnosis of asthma and monitoring of antiinflammatory treatment in asthmatic patients.
The study was conducted in a group of 101 steroid-naive asthmatics (56 allergic and 45 nonallergic) and 39 healthy volunteers. All patients underwent measurement of F(ENO), skin prick tests with common inhaled allergens, analysis of serum eosinophil cationic protein (ECP) and blood eosinophilia, and flow-volume spirometry. When the forced expiratory volume in the first second (FEV1) was less than 80% of predicted, reversibility of airway obstruction with a beta2-agonist was assessed. A nonspecific bronchial provocation test with histamine was carried out in asthmatic patients with a baseline FEV1 of more than 70% of predicted.
Compared to the healthy volunteers, F(ENO) was elevated in both groups of asthmatics. F(ENO) in the allergic asthma group was higher than in the group of nonallergic asthmatics. In allergic and nonallergic asthmatics, F(ENO) was significantly correlated with bronchial hyperresponsiveness to histamine, reversibility of airway obstruction, serum ECP levels, and blood eosinophilia. F(ENO) did not correlate with baseline FEV, in either group of asthmatics. In 31% of nonallergic and 9% of allergic patients, F(ENO) was less than 20 parts per billion.
We suggest that measurement of F(ENO) could be clinically useful in steroid-naive asthmatics and should be more widely used in clinical practice. Measurement of F(ENO) is a noninvasive, simple, and reproducible procedure, the results of which correlate with other routinely used methods in the diagnosis of asthma. However, it is worth noting that some patients, especially those with nonallergic asthma, do not display elevated F(ENO).
一氧化氮（NO）是一种具有强大生物活性的分子，在呼吸系统生理过程中发挥重要作用。哮喘患者中可诱导型一氧化氮合酶（iNOS）表达增加，呼出一氧化氮分数浓度（F(ENO)）升高。在抗炎治疗监测期间，F(ENO)的测量在评估支气管炎症方面的应用越来越受到认可。
本研究旨在评估一组未使用过类固醇的哮喘患者的F(ENO)，并评估该参数与哮喘诊断及哮喘患者抗炎治疗监测中使用的其他检查结果之间的关系。
研究纳入了101名未使用过类固醇的哮喘患者（56名变应性哮喘患者和45名非变应性哮喘患者）以及39名健康志愿者。所有患者均接受F(ENO)测量、常见吸入性变应原皮肤点刺试验、血清嗜酸性粒细胞阳离子蛋白（ECP）分析、血液嗜酸性粒细胞增多情况检查以及流速-容量肺活量测定。当第一秒用力呼气容积（FEV1）低于预测值的80%时，评估β2受体激动剂对气道阻塞的可逆性。对基线FEV1超过预测值70%的哮喘患者进行组胺非特异性支气管激发试验。
与健康志愿者相比，两组哮喘患者的F(ENO)均升高。变应性哮喘组的F(ENO)高于非变应性哮喘组。在变应性和非变应性哮喘患者中，F(ENO)与组胺诱导的支气管高反应性、气道阻塞可逆性、血清ECP水平以及血液嗜酸性粒细胞增多情况显著相关。在两组哮喘患者中，F(ENO)与基线FEV1均无相关性。在31%的非变应性患者和9%的变应性患者中，F(ENO)低于十亿分之20。
我们认为，F(ENO)的测量对未使用过类固醇的哮喘患者可能具有临床应用价值，应在临床实践中更广泛地应用。F(ENO)的测量是一种无创、简单且可重复的检查方法，其结果与哮喘诊断中其他常用方法相关。然而，值得注意的是，一些患者，尤其是非变应性哮喘患者，F(ENO)并未升高。
