Evaluation of laryngopharyngeal reflux in patients with interstitial lung disease (ILD) by a pharyngeal pH-probe

Background: Gastrooesophageal reflux (GER) may play a role in the pathogenesis and disease progression of ILDs by recurrent episodes of microaspiration initiating an inflammatory response with subsequent fibrosis. Yet, the prevalence of laryngopharyngeal reflux (LPR) reflecting GER is unknown in ILD patients. Aim: To assess the occurrence and severity of LPR in ILD patients Methods: 11 patients were enrolled (non-specific interstitial pneumonia (n=2), chronic hypersensitivity pneumonitis (n=3), idiopathic pulmonary fibrosis (n=3), desquamative interstitial pneumonia (n=1), connective tissue ILD (n=1), non classifiable ILD (n=1)) PH was measured over 24 hours in the posterior nasopharynx by a Restech Dx pH probe. Reflux symptoms, position and meals were documented on a portable device by the patients. Reflux symptoms were also assessed by a reflux symptom questionnaire (RSI). LPR was defined as pH Results: LPR was diagnosed in 10 out of 11 patients (46 % non-smoker, means: 68 years, forced vital capacity 74%, diffusing capacity of the lung 49 %). Mean pH was 6.2 (min 3.0, max 7.6). 18 % had an exclusively reflux during night, 82 % patients had a combined reflux in upright and lying position. 46 % had a LPR-positive RSI over 13 points. The RYAN-Score was significantly pathologic in 64 % of the cases. Conclusion: LPR seems to be an underestimated phenomenon in asymptomatic ILD patients. Lager numbers and longer observation periods are required to evaluate the impact on disease progression.