The value of 24 h ambulatory impedance-pH in diagnosis of gastroesophageal reflux disease

Objective To investigate the value of 24h ambulatory impedance-pH in diagnosis of gastroesophageal reflux disease(GERD).Methods One hundred and forty two patients with typical reflux symptoms or suggestive of gastroesophageal reflux were included.All patients underwent endoscopy and 24 h ambulatory impedance-pH monitoring.Among them,those with reflux esophagitis or DeMeester score ≥14.72 and SI ≥50% were defined as GERD+ group;others were defined as GERD-group.The parameters of 24h ambulatory impedance-pH were compared between two groups.Results Among all parameters of 24h esophageal pH monitoring,DeMeester score,the total time of pH 4 and time of reflux with pH 4 for 5min had better sensitivity and specificity for diagnosis of GERD.The single parameter of multichannel intraluminal impedance had a low sensitivity( 45%) in diagnosis of GERD.Compared to 24h esophageal pH monitoring,24h ambulatory impedance-pH detected more abnormal reflux episodes(χ2=14.65,P0.000).Conclusion The results suggest that endoscopy combined with 24h ambulatory impedance-pH may be a better choice for diagnosis of gastroesophageal reflux disease.