Objectives: Increased gastroesophageal reflux (GER) is common in children with cystic fibrosis (CF). We studied the occurrence of acid, weakly acidic (WA), and weakly alkaline (WALK) reflux in children with CF and evaluated a possible surrogate marker for risk of gastric content aspiration.
Patients and methods: Twenty-four children with CF underwent impedance-pH monitoring for detection of acid (pH < 4), WA (pH 4-7), and WALK-GER (pH > or = 7). In 11 children, cough was objectively recorded with esophageal manometry and the symptom association probability was calculated to determine the reflux-cough relation. Presence of bile acids (BA) was measured in the saliva of 65 patients with CF and 23 healthy children, respectively.
Results: Sixteen of the 24 children had increased GER (esophageal acid exposure). The majority of reflux events were acidic in nature. WA reflux was less common and WALK reflux was rare. The sequence reflux-cough was found in 8 of the 11 children and 1 of 11 children had a positive symptom association probability for reflux-cough. The sequence cough-reflux was found in only 3 of the 11 children. Only a small fraction of the total esophageal acid and volume exposure was secondary to cough. Twenty-three of the 65 children with CF had BA in saliva compared with none of the healthy controls.
Conclusions: Although WA-GER is uncommon, acid GER is prevalent in children with CF. It is a primary phenomenon and is not secondary to cough. One third of the children with CF have BA in saliva, which may indicate an increased risk for aspiration. However, the impact of salivary BA and potential aspiration on CF pulmonary disease needs further investigation.