RESUMO
BACKGROUND/AIMS: pH monitoring of the esophagus has been considered as the gold standard for the measurement of acid reflux. However, it has several limitations related to its inability to detect nonacid reflux. We conducted this study to characterize the proportion of acid and non-acid reflux events in children using pH-multichannel intraluminal impedance (MII) monitoring and to determine the correlation of the symptom index with non-acid and acid reflux events. METHOS: Seventy-five children, aged from 9 days to 12 years, underwent 24 hour pH-MII monitoring at Asan Medical Center from March 2006 to June 2007. We investigated the underlying disease and main problems related to gastroesophageal reflux (GER) of the patients, the number of acid and nonacid reflux, symptom index, symptom sensitivity index in pH monitoring only and pH-MII monitoring. RESULTS: While 2,247 reflux events were detected by MII, and only 967 reflux events were detected by pH probe alone. The percentage of acid reflux was 43% (967) and that of non-acid was 57% (1,280). The non-acid reflux increased at postprandial time (p<0.001). The symptom index increased when measured by pH-MII (31.1%) compared with those by pH probe alone (8.2%) (p=0.003). CONCLUSIONS: This study suggests that significant number of GER include non-acid reflux which cannot be detected by pH probe alone, therefore combining pH with MII monitoring is a valuable diagnostic tool for diagnosing GER in children.