Lai Kefang, Lin Ling, Liu Baojuan, Chen Ruchong, Tang Yan, Luo Wei, Chen Qiaoli
State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Diseases, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.
Respirology. 2016 May;21(4):683-8. doi: 10.1111/resp.12748. Epub 2016 Mar 10.
Patients presenting with refractory postinfectious cough may respond to glucocorticosteroids but it is unclear whether airway eosinophilic inflammation exists in those patients. We aimed to determine the airway inflammation and causes of subacute cough following acute upper respiratory tract infection (AURTI).
One hundred and sixteen patients with persistent cough lasting 3-8 weeks after upper respiratory tract infection were evaluated with differential cell count in induced sputum, spirometry and methacholine bronchial challenge testing.
In patients with subacute cough, sputum eosinophilia (median 8.5%,3.0-73.0%) was identified in 35 (33.6%) patients, 22 (18.5%) without bronchial hyperresponsiveness (BHR) were diagnosed as non-asthmatic eosinophilic bronchitis (NAEB), 13 (14.3%) of whom with BHR were diagnosed as cough variant asthma (CVA). Cough in patients with sputum eosinophilia improved after treatment with corticosteroids. Compared with postinfectious cough (PIC) and NAEB, CVA had significantly higher median eosinophil count in induced sputum (0.5% vs 7.5% vs 20.0%, P < 0.01). MMEF in CVA was significantly lower than PIC and NAEB (P < 0.05). The common causes of subacute cough following acute upper respiratory tract infection (AURTI) were PIC (37.8%), NAEB (18.5%), CVA (14.3%) and upper airway cough syndrome (UACS) (10.1%). Atopic cough (AC) (5.2%) and gastroesophageal reflux-related cough (GERC) (3.4%) were less common in subacute cough following AURTI, while 9 (7.8%) patients had unexplained cough.
Subacute cough following AURTI can be attributed to different entities, eosinophilic airway inflammation is common. Induced sputum should be considered when evaluating patients with subacute cough following acute upper respiratory tract infection.
难治性感染后咳嗽患者可能对糖皮质激素有反应，但尚不清楚这些患者是否存在气道嗜酸性粒细胞炎症。我们旨在确定急性上呼吸道感染（AURTI）后亚急性咳嗽的气道炎症及病因。
对116例上呼吸道感染后持续咳嗽3 - 8周的患者进行诱导痰细胞分类计数、肺功能测定和乙酰甲胆碱支气管激发试验评估。
在亚急性咳嗽患者中，35例（33.6%）患者痰嗜酸性粒细胞增多（中位数8.5%，3.0 - 73.0%），22例（18.5%）无支气管高反应性（BHR）的患者被诊断为非哮喘性嗜酸性粒细胞支气管炎（NAEB），其中13例（14.3%）有BHR的患者被诊断为咳嗽变异性哮喘（CVA）。痰嗜酸性粒细胞增多患者经糖皮质激素治疗后咳嗽改善。与感染后咳嗽（PIC）和NAEB相比，CVA诱导痰中的嗜酸性粒细胞中位数显著更高（0.5%对7.5%对20.0%，P < 0.01）。CVA的最大呼气中期流速显著低于PIC和NAEB（P < 0.05）。急性上呼吸道感染（AURTI）后亚急性咳嗽的常见病因是PIC（37.8%）、NAEB（18.5%）、CVA（14.3%）和上气道咳嗽综合征（UACS）（10.1%）。特应性咳嗽（AC）（5.2%）和胃食管反流相关性咳嗽（GERC）（3.4%）在AURTI后的亚急性咳嗽中较少见，而9例（7.8%）患者有不明原因咳嗽。
AURTI后的亚急性咳嗽可归因于不同病因，嗜酸性粒细胞气道炎症常见。评估急性上呼吸道感染后亚急性咳嗽患者时应考虑诱导痰检查。
