Brightling C E, Symon F A, Birring S S, Bradding P, Wardlaw A J, Pavord I D
Institute for Lung Health, University of Leicester, Division of Respiratory Medicine, Leicester UK.
Thorax. 2003 Jun;58(6):528-32. doi: 10.1136/thorax.58.6.528.
Eosinophilic bronchitis is a condition characterised by a corticosteroid responsive cough, sputum eosinophilia, and normal tests of variable airflow obstruction and airway responsiveness. We performed a detailed comparative immunopathological study to test the hypothesis that the different airway function in patients with eosinophilic bronchitis and asthma reflects differences in the nature of the lower airway inflammatory response.
Exhaled nitric oxide was measured and induced sputum, bronchoscopy, bronchial wash (BW), bronchoalveolar lavage (BAL), and bronchial biopsy were performed in 16 subjects with eosinophilic bronchitis, 15 with asthma, and 14 normal controls.
Both eosinophilic bronchitis and asthma were characterised by an induced sputum, BW and BAL eosinophilia, an increased number of epithelial and subepithelial eosinophils, and increased reticular basement membrane thickness. The median concentration of exhaled nitric oxide was higher in those with eosinophilic bronchitis (12 ppb) or asthma (8.5 ppb) than normal controls (2 ppb) (95% CI of the difference 5 to 16, p<0.0001 and 2 to 11.3, p=0.004, respectively). There were no group differences in epithelial integrity or the number of subepithelial T lymphocytes, mast cells or macrophages.
With the exception of our previously reported association of smooth muscle mast cell infiltration with asthma, the immunopathology of eosinophilic bronchitis and asthma are similar which suggests that eosinophilic airway inflammation, increased exhaled nitric oxide, and increased basement membrane thickening are regulated independently of airway hyperresponsiveness.
嗜酸性粒细胞性支气管炎是一种以糖皮质激素反应性咳嗽、痰液嗜酸性粒细胞增多，以及可变气流受限和气道反应性检查正常为特征的疾病。我们进行了一项详细的比较免疫病理学研究，以检验嗜酸性粒细胞性支气管炎和哮喘患者气道功能不同反映下呼吸道炎症反应性质差异的假说。
对16例嗜酸性粒细胞性支气管炎患者、15例哮喘患者和14例正常对照者进行呼出一氧化氮测量，并进行诱导痰、支气管镜检查、支气管冲洗（BW）、支气管肺泡灌洗（BAL）和支气管活检。
嗜酸性粒细胞性支气管炎和哮喘均以诱导痰、BW和BAL嗜酸性粒细胞增多、上皮和上皮下嗜酸性粒细胞数量增加以及网状基底膜厚度增加为特征。嗜酸性粒细胞性支气管炎患者（12 ppb）或哮喘患者（8.5 ppb）呼出一氧化氮的中位浓度高于正常对照者（2 ppb）（差异的95%可信区间分别为5至16，p<0.0001；2至11.3，p=0.004）。上皮完整性或上皮下T淋巴细胞、肥大细胞或巨噬细胞数量在各组之间无差异。
除了我们之前报道的平滑肌肥大细胞浸润与哮喘的关联外，嗜酸性粒细胞性支气管炎和哮喘的免疫病理学相似，这表明嗜酸性气道炎症、呼出一氧化氮增加和基底膜增厚增加是独立于气道高反应性而调节的。
