Impedance-pH analysis in diagnosis of gastroesophageal reflux in children and youth with asthma – preliminary report

Aim: The aim of the study was to assess pH-impedance usefulness in diagnostics of gastroesophageal reflux (GER) in children and teenagers with asthma.
Material and methods: In 26 children and teenagers, aged from 4 to 18 years (average age 13 years), 15 female, 11 male, 15 with controlled asthma, 4 with partly controlled and 7 with uncontrolled asthma 24-h pH-impedance monitoring was performed (Sandhill Scientific Inc., USA). Four children had no gastrointestinal symptoms, while twenty-two children complained about typical gastroesophageal symptoms. In seven of fifteen patients in whom endoscopy was performed, grade A oesophagitis according to the Los Angeles classification was confirmed.
Results: Acid GER was found in 11 (42.3%) patients, non-acid GER in 2 (7.7%) patients, and mixed GER in 5 (19.2%) patients. 8 (30.8%) patients were assessed as not suffering from GER. Concerning the group of patients with uncontrolled and partly controlled asthma, acid GER was found in 5 patients, non-acid GER in 1 patient, mixed GER in 2 patients, and 3 were assessed as not suffering from GER. In 4 patients, including 3 with controlled asthma, proximal GER events occurred. Endoscopic oesophagitis was recognized in 1/2 patients with non-acid GER, 2/5 with acid GER, 2/4 with mixed GER and 2/4 without GER. The total number concerning all GER events was 1728 (on average 66.46), 1161 acid events (67.2%), and 567 (32.8%) non-acid events. The most frequent symptoms presented during recording were: abdominal pain, heartburn and belching. Symptoms presented by the patients during the recording were mostly associated with GER events. Considering the group with acid GER the result of classical pH-metry was abnormal in nine of them and with mixed GER in five of them. In patients with non-acid GER or without GER the result of pH-metry was normal in all but one patient with endoscopic oesophagitis. Conclusions: The majority of children and youth with asthma do have GER. In children and youth with asthma pH-impedance monitoring could identify non-acid GER, acid GER and mixed GER, which will not always be recognized by classical pH-metry. Some children and youth with asthma and GER (some with endoscopic oesophagitis) do not have gastrointestinal symptoms. Some patients with asthma and typical gastroesophageal symptoms do not have GER. It seems that the severity of asthma has no influence on the prevalence of GER. The majority of GER events identified by pH-impedance monitoring in children and youth with asthma do not reach the high oesophageal zone. Based on that observation, direct aspiration into the airways seems not to be the main pathway of respiratory symptoms in asthma.