痰液炎性细胞与儿童发作期哮喘关系的研究

The relationship between sputum inflammatory cells and asthma state in children

目的 探讨反映气道炎症状况的痰液炎性细胞测定在哮喘临床中的应用价值。方法 应用Pin等的诱导痰技术 ,对 10 5例哮喘发作期儿童 (上呼吸道感染诱因组 3 0例 ,非感染诱因组 75例 )的新鲜痰涂片进行迈 格氏加姬姆萨 (May Gr櫣ｎｗａｌｄ′ｓ+Gimsa)复染法和巴氏 (Papanicolaou)染色法染色 ,做细胞学分类计数 ,测定痰液炎性细胞百分比 ,同步检测变应原皮试和肺通气功能。结果 上呼吸道感染诱因组中痰液嗜酸细胞和中性粒细胞中位数分别为 4 %、74 %与非感染诱因组 (分别为13 %、3 0 % )比较 ,两种细胞各组间差异均有显著性 (P均 <0 0 1)。非吸入激素组和不正规吸入激素组中的嗜酸细胞中位数分别为 7%、15 % ,与正规吸入激素组 ( 1% )比较差异均有显著性 (P均 <0 0 5 )。伴有中性粒细胞增高的嗜酸细胞型 18例中 12例为中、重度哮喘发作者 ( 67% ) ,气道阻塞明显 ,第 1秒用力呼出量占用力肺活量的百分比的均值 ( 66 0 9% )与嗜酸细胞型和非嗜酸细胞型 (分别为 84 16%、84 90 % )比较差异均有显著性 (P均 <0 0 5 )。结论 痰液炎性细胞可能成为反映哮喘患儿气道炎症程度 ,评价药物疗效的指标。

Objective Airway inflammation is considered to be the cause of asthma. The inflammatory component of asthma is usually assessed indirectly by symptoms and spirometry, which may often be inaccurate. The introduction of induced sputum noninvasively makes it possible to examine the inflammatory components. The examination of sputum cell counts can now be a direct and reliable method to measure indices of airway inflammation. The aim of this study was to evaluate the clinical application of the detection of sputum inflammatory cells reflecting the state of airway inflammation in asthmatic children. Methods Sputum was collected from 105 children with asthma attending the respiratory clinic and in the ward at Beijing Children′s Hospital. The children aged 4 to 14 years, the average age was 8.8 years; 70 of them were male and 35 were female. The causes of asthma attack were divided into 2 group: respiratory infection (n=30, 28.6%) and non-respiratory infection (n=75, 71.4%). The application of inhaled corticosteroids therapy was divided into 3 group: non-preventing therapy (n=73, 69.5%), background asthma therapy (n=12, 11.4%) or irregular inhaled preventing (n=20, 19.1%). The asthma attacks had 3 inflammatory cell patterns: eosinophilic (n=48, 45.7%), combined eosinophilic/neutrophilic (E/N; n=18, 17.1%) or noneosinophilic (n=39, 37.1%). Sputum samples were obtained by spontaneous expectoration or by hypertonic saline aerosol induction. Sputum smear was stained with May-Grünwald′s plus Gimsa and Papanicolaou′s methods. Differential inflammatory cells counts were performed by counting 500 cells under the light microscope, while patients were tested for allergy by skin print test and pulmonary function. Results The percentage of eosinophils in sputum of asthmatic children with respiratory infection was significantly lower than that without respiratory infection (median 4% vs 13%, P=0.001). Contrarily, the percentage of neutrophils in sputum of children with cause of respiratory tract infection was significantly higher compared with asthmatic children of non-infection cause (median 74% vs 30%, P=0.001). Sputum eosinophils in patients with inhaled corticosteroids as background asthma therapy (median 1%) was significantly different from sputum eosinophils in patients with irregular inhaled preventer (median 15%, P=0.009) or non-preventing therapy (median 7%, P=0.03). Twelve of 18 (67%) patients in the mixed E/N group had moderate and severe asthma attacks, and had a lower forced expiratory volume in one second (FEV 1)% predicted than that in eosinophilic group or noneosinophilic group (mean 66.09% vs 84.16% or 84.90%, P<0.05). Conclusion Sputum inflammatory cells may be a useful marker reflecting the state of airway inflammation in assessment of the therapeutic efficacy.