Centre for Infection and Inflammation Research, and Prince of Wales Clinical School, University of New South Wales, Sydney, Australia.
J Breath Res. 2012 Mar;6(1):016003. doi: 10.1088/1752-7155/6/1/016003. Epub 2012 Jan 10.
Gastro-oesophageal reflux disease (GORD) has been implicated in the worsening of several respiratory disorders. Current methods of diagnosis lack accuracy, are invasive and can be costly. Recently, novel methods of analysing lung pathophysiology have been developed including the use of an electronic nose and analysis of components of exhaled breath condensate (EBC). We hypothesised that these methods would distinguish patients with GORD from those without GORD in the common obstructive lung diseases and healthy controls. In a cross-sectional study, exhaled breath was analysed using the Cyranose 320 electronic nose, using principal components and canonical discriminant analyses. EBC pH and pepsin were quantified using a pH meter and an enzyme-linked immunosorbent assay, respectively. A standardized reflux disease questionnaire (RDQ) was used to assess reflux symptoms. The Cyranose 320 distinguished exhaled breath profiles of obstructive lung disease patients without GORD from obstructive lung disease patients with GORD (p = 0.023, accuracy 67.6%), asthmatic patients with reflux from asthmatics without GORD (85%, p = < 0.015, interclass M distance > 2.8), but did not produce as robust a profile for patients with COPD and COPD with GORD (p = 0.047, accuracy 64%). Patients with obstructive lung disease and GORD had significantly higher levels of EBC pepsin (9.81 ± interquartile range (IQR) 4.38 ng ml(-1)) than those without GORD (4.6 ± IQR 6.95 ng ml(-1)), as well as healthy controls (3.44 ± IQR 7.87 ng ml(-1); p = < 0.013). EBC pH was not significantly related to the presence of GORD in any group. The RDQ results correlated significantly with the presence of EBC pepsin. This pilot study has shown that exhaled breath profiling can be used for detecting GORD in obstructive lung diseases. While the electronic nose was useful in asthma, EBC pepsin was more helpful in COPD. In this study, several different confounders could potentially have affected results and larger prospective interventional studies are needed.
胃食管反流病（GORD）与多种呼吸系统疾病的恶化有关。目前的诊断方法准确性差、有创且昂贵。最近，已经开发出了分析肺病理生理学的新方法，包括使用电子鼻和分析呼出气冷凝物（EBC）的成分。我们假设这些方法将能够区分患有 GORD 的患者与患有阻塞性肺部疾病和健康对照组的患者。在一项横断面研究中，使用 Cyranose 320 电子鼻分析呼出气，使用主成分和典型判别分析。使用 pH 计和酶联免疫吸附测定法分别定量 EBC pH 和胃蛋白酶。使用标准化的反流疾病问卷（RDQ）评估反流症状。Cyranose 320 区分了无 GORD 的阻塞性肺部疾病患者与有 GORD 的阻塞性肺部疾病患者（p = 0.023，准确性 67.6%）、有反流的哮喘患者与无 GORD 的哮喘患者（85%，p < 0.015，类内 M 距离 > 2.8），但对于 COPD 和 COPD 伴 GORD 患者的特征不明显（p = 0.047，准确性 64%）。患有阻塞性肺部疾病和 GORD 的患者的 EBC 胃蛋白酶水平显著高于无 GORD 的患者（9.81 ± IQR 4.38 ng ml(-1))（p < 0.013）。EBC pH 与任何组的 GORD 存在均无显著相关性。RDQ 结果与 EBC 胃蛋白酶的存在显著相关。这项初步研究表明，呼出气分析可用于检测阻塞性肺部疾病中的 GORD。电子鼻在哮喘中有用，而 EBC 胃蛋白酶在 COPD 中更有帮助。在这项研究中，一些不同的混杂因素可能会影响结果，需要更大的前瞻性干预性研究。
