Is it GER? Different diagnostic approaches for detection of gastroesophageal reflux in patients with chronic cough

Background: Gastroesophageal reflux (GER) is a common cause of chronic cough. Different methods can be used to detect it. The limited accessibility of some devices or difficulties in assessment of relationship between GER and cough may influence their practical usefulness. Objectives: To assess the utility of different methods in the diagnosis of GER in patients with chronic cough. Methods: We included 60 consequent, nonsmoking, adult patients, with history of cough longer than 8 weeks, with normal chest radiograph. We used the Carlsson questionnaire (CQ), assessment of abnormalities in larynx mucosa (Belafsky reflux finding score, RFS), upper gastrointestinal tract radiography, 24-hour-pH monitoring and multichannel impedance (MI) of esophagus. Results: Sixty patients were included (M/F =1:1.86), mean age 48.8 yrs, mean cough duration 260 weeks (range 16-1440). Sixteen subjects were excluded from further studies due to consent withdrawal or technical problems with pH probe insertion. Positive results of CQ and RFS were observed in 13 and 50/54 cases respectively. Mean calculated RFS was 11.7 points. Esophageal hernia or reflux during radiography was shown in 6 and 7/54 pts, respectively. Increased esophagus exposure to acid reflux was diagnosed in 43/58 pts using pH monitoring alone, and in 37/44 on the basis of MI. Time-relationship between GER and cough was found in 23 and 21 cases, respectively. MI probe was slightly worse tolerated. Conclusions: Diagnosis of GER was most frequent on the basis of RFS and MI. Combination of few methods allows to recognize GER more precisely. The time relationship between GER and cough, can be assessed not by all devices used.