呼出气一氧化氮和诱导痰诊断哮喘更迅速准确

用呼出气一氧化氮（FENO）和诱导痰来诊断哮喘，比传统方法如测量最大呼气流、呼吸量测定、气道对吸入性支气管扩张剂或口服激素的反应等远为优越。以上每种传统检测的敏感性都远低于FENO和诱导痰的。

这是第一个比较国际指导方针中推荐常规诊断检查和“最新”方法用于诊断哮喘的研究，发表于2004年第4期《美国呼吸与急救医学杂志》（American Journal of Respiratory and Critical Care Medicine）。作者、新西兰达尼丁市Otago大学的泰勒（Robin Taylor）和同事要求47名有疑似哮喘症状的病人接受了一系列上述检查。结果传统检查的敏感性在0～47%之间，而FENO为88%，诱导痰为86%。本研究证实，常规检测对哮喘的诊断价值“有限”，它们的“敏感性差，而且预测值远低于FENO和诱导痰的”。

泰勒说，他们对这一结论并不感到吃惊，“因为我们使用一氧化氮的日常经验已让我们相信：它是一种极好的检查。只是这种经验还需要确切的验证——因此我们进行了这个研究”。

FENO还与诱导痰分析不一样，后者有技术上的要求，通常不能进行，而FENO测量“很快，容易操作，加入到现行肺功能试验检测中应很容易”，作者指出。

Am J Respir Crit Care Med. 2004 Feb 15;169(4):473-8.

Diagnosing asthma: comparisons between exhaled nitric oxide measurements and conventional tests.

Smith AD, Cowan JO, Filsell S, McLachlan C, Monti-Sheehan G, Jackson P, Taylor DR.

Dunedin School of Medicine, University of Otago Medical School, Dunedin, New Zealand.

International guidelines recommend a range of clinical tests to confirm the diagnosis of asthma. These focus largely on identifying variable airflow obstruction and responses to bronchodilator or corticosteroid. More recently, exhaled nitric oxide (FE(NO)) measurements and induced sputum analysis to assess airway inflammation have been highlighted. However, to date, no systematic comparisons to confirm the diagnostic utility of each of these methods have been performed. To do so, we investigated 47 consecutive patients with symptoms suggestive of asthma, using a comprehensive fixed-sequence series of diagnostic tests. Sensitivities and specificities were obtained for peak flow measurements, spirometry, and changes in these parameters after a trial of steroid. Comparisons were made against FE(NO) and sputum cell counts. Sensitivities for each of the conventional tests (0-47%) were lower than for FE(NO) (88%) and sputum eosinophils (86%). Overall, the diagnostic accuracy when using FE(NO) and sputum eosinophils was significantly greater. Results for conventional tests were not improved, using a trial of steroid. We conclude that FE(NO) measurements and induced sputum analysis are superior to conventional approaches, with exhaled nitric oxide being most advantageous because the test is quick and easy to perform.

欢迎医学空间注册用户来信索取原文