The impact of reflux burden on Pseudomonas positivity in children with Cystic Fibrosis

OBJECTIVES: Nonacid gastroesophageal reflux (GER), particularly in patients taking acid suppression, has been implicated as a cause of respiratory infections. We hypothesize that children with cystic fibrosis (CF) and a higher nonacid reflux burden have greater rates of Pseudomonas aeruginosa (Pa) infection than patients with a lower reflux burden. STUDY DESIGN: We reviewed the multichannel intraluminal impedance (pH-MII) tracings of 35 patients with CF between 2003 and 2010. We compared the reflux profiles between those patients who were Pa positive and Pa negative. RESULTS: The mean age was 13.5 ± 5.8 years. Twenty-seven patients (76%) were Pa positive. Ninety seven percent of patients were taking proton pump inhibitors during pH-MII testing. The mean percentage of time pH was <4 was 8.5 ± 12%. Pa patients had a significantly higher total, acid and proximal nonacid reflux burden (P < 0.009). There was a negative correlation between nonacid reflux burden and FEV1 (r = -0.397, P = 0.03) and between total number of reflux events and FEV1 (r = -0.474, P = 0.009). After adjusting for age and FEV1, total reflux burden remains significantly associated with Pa positivity (P = 0.055). CONCLUSIONS: Increased reflux burden may predispose patients to Pa infection and worse lung function.