Utility of inpatient 24-hour intraesophageal pH monitoring in diagnosis of gastroesophageal reflux.

The aims of the present study were to evaluate the accuracy of 24-hr intraesophageal pH monitoring in the diagnosis of gastroesophageal reflux in the hospital setting and to establish whether there were any differences in terms of reflux events between patients with and without endoscopic esophagitis. Fifteen control subjects and 47 patients with proven gastroesophageal reflux disease were studied. A composite score of reflux events (number of reflux episodes; total, upright, and supine reflux time; number of refluxes lasting more than 5 min; and duration of the longest reflux) provided the best discrimination between controls and patients (94% sensitivity and 100% specificity). Patients with esophagitis showed concurrently a longer total reflux time and supine reflux time, and more prolonged reflux episodes than those without esophagitis. On the other hand the severity of esophagitis was directly related to the duration of both total and supine reflux. The results indicate that inpatient 24-hr pH-metry is very accurate in the diagnosis of gastroesophageal reflux. They also suggest that prolonged esophageal exposure to acid, particularly at night, and slow esophageal acid clearing are factors that determine the appearance and/or perpetuation of esophagitis in patients with reflux.