de Groot Jantina C, Ten Brinke Anneke, Bel Elisabeth H D
Department of Respiratory Medicine, Medical Centre Leeuwarden, Leeuwarden, The Netherlands.
Department of Respiratory Medicine, Amsterdam Medical Centre, Amsterdam, The Netherlands.
ERJ Open Res. 2015 Sep 23;1(1). doi: 10.1183/23120541.00024-2015. eCollection 2015 May.
Now that it is generally accepted that asthma is a heterogeneous condition, phenotyping of asthma patients has become a mandatory part of the diagnostic workup of all patients who do not respond satisfactorily to standard therapy with inhaled corticosteroids. Late-onset eosinophilic asthma is currently one of the most well-defined asthma phenotypes and seems to have a different underlying pathobiology to classical childhood-onset, allergic asthma. Patients with this phenotype can be identified in the clinic by typical symptoms (few allergies and dyspnoea on exertion), typical lung function abnormalities ("fixed" airflow obstruction, reduced forced vital capacity and increased residual volume), typical comorbidities (nasal polyposis) and a good response to systemic corticosteroids. The definitive diagnosis is based on evidence of eosinophilia in bronchial biopsies or induced sputum, which can be estimated with reasonable accuracy by eosinophilia in peripheral blood. Until recently, patients with eosinophilic asthma had a very poor quality of life and many suffered from frequent severe exacerbations or were dependent on oral corticosteroids. Now, for the first time, novel biologicals targeting the eosinophil have become available that have been shown to be able to provide full control of this type of refractory asthma, and to become a safe and efficacious substitute for oral corticosteroids.
既然哮喘是一种异质性疾病这一观点已被广泛接受，那么对于所有对吸入性糖皮质激素标准治疗反应不佳的患者，哮喘患者的表型分析已成为诊断检查的必要组成部分。迟发性嗜酸性粒细胞性哮喘是目前定义最明确的哮喘表型之一，其潜在病理生物学似乎与典型的儿童期起病的过敏性哮喘不同。具有这种表型的患者在临床上可通过典型症状（很少有过敏反应和运动时呼吸困难）、典型的肺功能异常（“固定性”气流受限、用力肺活量降低和残气量增加）、典型的合并症（鼻息肉）以及对全身用糖皮质激素的良好反应来识别。确诊基于支气管活检或诱导痰中嗜酸性粒细胞增多的证据，外周血嗜酸性粒细胞增多可较为准确地评估这一情况。直到最近，嗜酸性粒细胞性哮喘患者的生活质量一直很差，许多患者频繁遭受严重发作或依赖口服糖皮质激素。现在，首次有了针对嗜酸性粒细胞的新型生物制剂，已证明这些生物制剂能够完全控制这类难治性哮喘，并成为口服糖皮质激素安全有效的替代品。
