Silvestri M, Spallarossa D, Frangova Yourukova V, Battistini E, Fregonese B, Rossi G A
Divisione di Pneumologia, Istituto G. Gaslini, Genoa, Italy.
Eur Respir J. 1999 Feb;13(2):321-6. doi: 10.1034/j.1399-3003.1999.13b17.x.
Increased levels of nitric oxide have been found in expired air of patients with asthma, and these are thought to be related to the airway inflammatory events that characterize this disorder. Since, in adults, bronchial inflammatory changes are present even in mild disease, the present study was designed to evaluate whether a significant proportion of children with mild-intermittent asthma could have increased exhaled air NO concentrations. Twenty-two atopic children (aged 11.1+/-0.8 yrs) with mild-intermittent asthma, treated only with inhaled beta2-adrenoreceptor agonists on demand and 22 age-matched controls were studied. NO concentrations in orally exhaled air, measured by chemiluminescence, were significantly higher in asthmatics, as compared to controls (19.4+/-3.3 parts per billion (ppb) and 4.0+/-0.5 ppb, respectively; p<0.01). Interestingly, 14 out of 22 asthmatic children had NO levels >8.8 ppb (i.e. >2 standard deviations of the mean in controls). In asthmatic patients, but not in control subjects, statistically significant correlations were found between exhaled NO levels and absolute number or percentage of blood eosinophils (r=0.63 and 0.56, respectively; p<0.01, each comparison). In contrast, exhaled NO levels were not correlated with forced expiratory volume in one second (FEV1) or forced expiratory flows at 25-75% of vital capacity (FEF25-75%) or forced vital capacity (FVC), either in control subjects, or in asthmatic patients (p>0.1, each correlation). These results suggest that a significant proportion of children with mild-intermittent asthma may have airway inflammation, as shown by the presence of elevated levels of nitric oxide in the exhaled air. The clinical relevance of this observation remains to be established.
在哮喘患者的呼出气体中发现一氧化氮水平升高，这些被认为与表征该疾病的气道炎症事件有关。由于在成年人中，即使是轻度疾病也存在支气管炎症变化，因此本研究旨在评估是否有相当比例的轻度间歇性哮喘儿童呼出气体中的一氧化氮浓度会升高。研究了22名患有轻度间歇性哮喘的特应性儿童（年龄11.1±0.8岁），他们仅按需使用吸入型β2肾上腺素能激动剂进行治疗，并与22名年龄匹配的对照者进行了比较。通过化学发光法测量的口腔呼出气体中的一氧化氮浓度，哮喘患者显著高于对照者（分别为19.4±3.3十亿分之一（ppb）和4.0±0.5 ppb；p<0.01）。有趣的是，22名哮喘儿童中有14名的一氧化氮水平>8.8 ppb（即高于对照者平均值的2个标准差）。在哮喘患者中，而非对照受试者中，呼出一氧化氮水平与血液嗜酸性粒细胞的绝对数量或百分比之间存在统计学显著相关性（分别为r = 0.63和0.56；每次比较p<0.01）。相比之下，无论是在对照受试者还是哮喘患者中，呼出一氧化氮水平与一秒用力呼气量（FEV1）、肺活量25%-75%时的用力呼气流量（FEF25-75%）或用力肺活量（FVC）均无相关性（每次相关性p>0.1）。这些结果表明，相当比例的轻度间歇性哮喘儿童可能存在气道炎症，呼出气体中一氧化氮水平升高即表明了这一点。这一观察结果的临床相关性仍有待确定。
