Airway response to acid instillation in esophagus in bronchial asthma.

ABSTRACT

OBJECTIVE: An increased incidence of gastroesophageal reflux has been reported in patients with bronchial asthma. We studied the pulmonary effects of acid instillation in the esophagus. METHODS: Fifteen patients with bronchial asthma and 15 healthy adults in the age group 15-50 years were studied. The control subjects were first screened for bronchial hyperreactivity by a methacholine challenge test. Patients and controls were both subjected to modified Bernstein test. Spirometry was done at baseline and after each instillation of either acid or saline. Respiratory and reflux symptoms were noted after each infusion and antacid administration. RESULTS: Five patients and one control subject had history of reflux symptoms (p < 0.05) and six patients had nocturnal asthma. There was a significant fall in FEV1/FVC after acid infusion patients; this improved significantly after antacid administration. All six patients with nocturnal asthma had respiratory signs or symptoms and had more than 20% fall in FEV1 on acid instillation in the esophagus, while none in the control group developed the same. CONCLUSIONS: Gastroesophageal reflux occurs more frequently in patients with bronchial asthma and acid instillation in the esophagus triggers bronchoconstriction.