Gastro-esophageal reflux induced cough with airway hyperresponsiveness.

To investigate the characteristics of gastroesophageal reflux induced cough (GERC) with airway hyperresponsiveness (AHR). Compared to patients with GERC alone and healthy subjects, cough sensitivity, multi-channel intraluminal impedance combined with pH monitoring and airway inflammation were evaluated in patients with GERC and AHR. 23 patients were definitely diagnosed as acid reflux induced GERC, 9 patients developed AHR concomitantly. When compared with GERC patients, patients with AHR had significantly increased number of proximal extent episodes (21.5 (28.6) vs. 7.5 (1.8), Z = -2.038, P = 0.042) and increased proportion of proximal extent episodes to total refluxes episodes (24.5 (13.5)% vs. 4.2 (7.3)%, Z = -2.138, P = 0.032), and the level of IL-8 in the airway of these patients was significantly higher than that in healthy subjects (71.1 (64.0) vs. 24.3 (35.2) pg/ml, Z = -2.013, P = 0.044). Gastroesophageal reflux may cause neutrophilic airway inflammation due to the acid reflux into the airway, which results in AHR. However, AHR is not definitely able to cause chronic cough. Thus differential diagnosis is required in clinical practice.