Correlation Between the Radiological Observation of Gastroesophageal Reflux on an Esophagram and Findings of 24-Hour Ambulatory Combined pH Impedance Testing

Abstract

Introduction: 24-hour ambulatory pH-impedance studies are the gold standard for diagnosing gastroesophageal reflux disease (GERD). Many patients with upper gastrointestinal complaints also undergo barium esophagrams (UGI) and reflux of barium from the stomach into the esophagus is commonly reported. Prior studies have shown conflicting results with regards to the correlation between reflux on barium studies and GERD. However, it has been suggested that high level reflux on an esophagram is diagnostic of GERD. Methods: We aimed to assess the correlation between the observation of any gastroesophageal reflux or high level gastroesophageal reflux on UGI and findings on non-synchronous 24 hour ambulatory combined pH-impedance study. Adult patients in whom both an UGI and non-synchronous ambulatory combined 24-hour pH impedance study were obtained at Mayo Clinic between January 2012 and November 2013 were included. Data from non-synchronous pH-impedance studies were correlated with the findings on UGI as reported by a radiologist. High level gastroesophageal reflux (GER) was defined as reflux to or above the thoracic outlet. The pH impedance test was considered positive if either the total esophageal acid exposure or total number of impedance episodes were elevated among patients on or off acid suppressive therapy. Results: A total of 240 patients were identified, 36% were male and the median age was 56 (range: 19 - 83). Sixteen pH studies (6%) were incomplete, uncertain or failed and were excluded. 51% patients were on a PPI during the pH impedance test. The median DeMeester score was 10.6 (range 0.8 - 164). The sensitivity and specificity of reflux on a barium study for GERD was 29% (95% CI 20 - 39) and 86% (95% CI 80 - 92), respectively. 46 patients (20%) had high level GERD noted on UGI, and the pH-impedance study was positive in 92 (76%) (Table 1).Table 1Conclusion: The sensitivity and specificity of the radiological observation of gastroesophageal reflux by UGI for predicting an abnormal 24 hour pH impedance study is suboptimal. Whilst prior studies have previously reported that high level reflux on a UGI has 100% sensitivity for GERD, we found that up to a quarter of such patients do not have GERD based on pH-impedance criteria.