Department of Clinical Pathophysiology, University of Turin, Turin, Italy.
J Allergy Clin Immunol. 2011 Feb;127(2):412-9. doi: 10.1016/j.jaci.2010.10.038. Epub 2010 Dec 16.
Perennial rhinitis (PR), chronic rhinosinusitis (CRS), or both, asthma, and gastroesophageal reflux disease (GERD) are the most frequent triggers of chronic cough (CC). Extrathoracic airway receptors might be involved in all 3 conditions because asthma is often associated with PR/CRS and gastroesophageal refluxate might reach the upper airway. We previously found that most patients with rhinosinusitis, postnasal drip, and pharyngolaryngitis show laryngeal hyperresponsiveness (LHR; ie, vocal cord adduction on histamine challenge) that is consistent with an irritable larynx.
We sought to evaluate the role of LHR in patients with CC.
LHR and bronchial hyperresponsiveness (BHR) to histamine were assessed in 372 patients with CC and in 52 asthmatic control subjects without cough (asthma/CC-). In 172 patients the challenge was repeated after treatment for the underlying cause of cough.
The primary trigger of CC was PR/CRS in 208 (56%) patients, asthma in 41 (11%) patients (asthma/CC+), GERD in 62 (17%) patients, and unexplained chronic cough (UNEX) in 61 (16%) patients. LHR prevalence was 76% in patients with PR/CRS, 77% in patients with GERD, 66% in patients with UNEX, 93% in asthma/CC+ patients, and 11% in asthma/CC- patients. Upper airway disease was found in most (95%) asthma/CC+ patients and in 6% of asthma/CC- patients. BHR discriminated asthmatic patients and atopy discriminated patients with PR/CRS from patients with GERD and UNEX. Absence of LHR discriminated asthmatic patients without cough. After treatment, LHR resolved in 63% of the patients and improved in 11%, and BHR resolved in 57% and improved in 18%.
An irritable larynx is common in patients with CC and indicates upper airway involvement, whether from rhinitis/sinusitis, gastric reflux, or idiopathic sensory neuropathy.
常年性鼻炎（PR）、慢性鼻-鼻窦炎（CRS）或两者兼有、哮喘和胃食管反流病（GERD）是慢性咳嗽（CC）最常见的诱因。胸外气道感受器可能与这 3 种疾病都有关，因为哮喘常与 PR/CRS 相关，而胃食管反流物可能到达上呼吸道。我们之前发现，大多数患有鼻-鼻窦炎、后鼻滴注和咽-喉炎的患者表现出喉高反应性（LHR；即组胺激发时声带内收），这与易激惹的声带一致。
我们旨在评估 LHR 在 CC 患者中的作用。
我们评估了 372 例 CC 患者和 52 例无咳嗽的哮喘对照患者（哮喘/CC-）的 LHR 和支气管高反应性（BHR）对组胺的反应。在 172 例患者中，在针对咳嗽潜在病因进行治疗后重复了该试验。
CC 的主要诱因在 208 例（56%）患者中为 PR/CRS，在 41 例（11%）患者中为哮喘（哮喘/CC+），在 62 例（17%）患者中为 GERD，在 61 例（16%）患者中为不明原因的慢性咳嗽（UNEX）。PR/CRS 患者中 LHR 的发生率为 76%，GERD 患者中为 77%，UNEX 患者中为 66%，哮喘/CC+患者中为 93%，哮喘/CC-患者中为 11%。上气道疾病在大多数（95%）哮喘/CC+患者和 6%的哮喘/CC-患者中被发现。BHR 可区分哮喘患者，特应性可区分 PR/CRS 患者与 GERD 和 UNEX 患者。无 LHR 可区分无咳嗽的哮喘患者。治疗后，63%的患者 LHR 缓解，11%的患者 LHR 改善，57%的患者 BHR 缓解，18%的患者 BHR 改善。
在 CC 患者中，易激惹的声带很常见，表明上气道受累，无论是由鼻炎/鼻窦炎、胃反流还是特发性感觉神经病引起的。
