Ulrik C S
Department of Medicine B, National University Hospital, Copenhagen, Denmark.
Clin Exp Allergy. 1995 Sep;25(9):820-7. doi: 10.1111/j.1365-2222.1995.tb00024.x.
Recently it has been suggested that the bronchospasm and hyperresponsiveness phenomena observed in asthma are secondary to the actions of the eosinophils; the purpose of this study was to evaluate the relationship between the peripheral number of eosinophils and various markers of disease activity in a group of asthmatics examined in childhood (mean age 10 years) and early adulthood (mean age 21 years).
The relationship between eosinophil count and pulmonary function (FEV1), respiratory symptoms, bronchial responsiveness to histamine and diurnal variation in peak expiratory flow rate (PEF) was studied in 70 subjects with bronchial asthma, of whom 24 had intrinsic and 46 extrinsic asthma. Self-reported symptoms of asthma were graded on a scale from 0 to 5, where 0 = no symptoms within the preceding 12 months and 5 = daily including nocturnal symptoms, and histamine responsiveness was analysed by means of the dose-response slope (DRS).
In both childhood and adulthood, a direct correlation was found between blood eosinophil count and symptom score (r = 0.69, P < 0.001 and r = 0.58, P < 0.001, respectively), whereas inverse correlations were observed between number of eosinophils and FEV1 % predicted (r = -0.75, P < 0.001 and r = -0.80, P < 0.001, respectively). Furthermore, in adulthood, eosinophil count was found to be significantly correlated to histamine responsiveness (logDRS) (r = 0.65, P < 0.001) and diurnal PEF variation (r = 0.81, P < 0.001); these correlations were also noted after dividing the subjects into intrinsic and extrinic asthmatics. In both groups of subjects a significant inverse correlation was also found between histamine responsiveness and prechallenge FEV1 % predicted. The eosinophil count in childhood was weakly correlated to the symptom score in adulthood (r = 0.29, P < 0.02).
This study showed a relationship between eosinophil count and severity of asthmatic symptoms, level of pulmonary function, histamine responsiveness and diurnal variation in PEF in both intrinsic and extrinsic asthma; suggesting that the peripheral eosinophil count reflects asthmatic activity, and possibly the degree of inflammation in the airways, in both children and adults. Furthermore, a low number of eosinophils in childhood might be related to a relatively favourable prognosis with regard to symptoms of asthma in early adulthood.
最近有人提出，哮喘中观察到的支气管痉挛和高反应性现象是嗜酸性粒细胞作用的继发结果；本研究的目的是评估一组在儿童期（平均年龄10岁）和成年早期（平均年龄21岁）接受检查的哮喘患者外周嗜酸性粒细胞数量与疾病活动的各种标志物之间的关系。
研究了70例支气管哮喘患者的嗜酸性粒细胞计数与肺功能（FEV1）、呼吸道症状、支气管对组胺的反应性以及呼气峰值流速（PEF）的日变化之间的关系，其中24例为内源性哮喘，46例为外源性哮喘。自我报告的哮喘症状按0至5级评分，其中0 = 前12个月内无症状，5 = 每日有症状，包括夜间症状，并通过剂量反应斜率（DRS）分析组胺反应性。
在儿童期和成年期，血液嗜酸性粒细胞计数与症状评分之间均发现直接相关性（分别为r = 0.69，P < 0.001和r = 0.58，P < 0.001），而嗜酸性粒细胞数量与预测的FEV1 %之间观察到负相关性（分别为r = -0.75，P < 0.001和r = -0.80，P < 0.001）。此外，在成年期，发现嗜酸性粒细胞计数与组胺反应性（logDRS）显著相关（r = 0.65，P < 0.001）和PEF日变化（r = 0.81，P < 0.001）；将受试者分为内源性和外源性哮喘患者后也观察到这些相关性。在两组受试者中，组胺反应性与激发前预测的FEV1 %之间也发现显著负相关性。儿童期的嗜酸性粒细胞计数与成年期的症状评分弱相关（r = 0.29，P < 0.02）。
本研究表明，内源性和外源性哮喘患者的嗜酸性粒细胞计数与哮喘症状严重程度、肺功能水平、组胺反应性和PEF日变化之间存在关系；提示外周嗜酸性粒细胞计数反映了儿童和成人的哮喘活动，可能还有气道炎症程度。此外，儿童期嗜酸性粒细胞数量低可能与成年早期哮喘症状的相对良好预后有关。
