Barium study associated with water siphon test in gastroesophageal reflux disease and its complications

The aim of this study was to evaluate the role of digital cineradiography associated with the water siphon test (WST) in the diagnosis of gastroesophageal reflux and to compare the results with oesophageal motility study, pH monitoring and endoscopy associated with biopsy and histology.

One hundred and sixty consecutive patients underwent digital cineradiography with WST, motility study, pH monitoring and endoscopy with biopsy. The presence of gastroesophageal reflux, oesophagitis, Barrett's oesophagus and intestinal metaplasia was evaluated.

WST vs. pH monitoring showed sensitivity of 71%, specificity of 31%, positive predictive value (PPV) of 53% and negative predictive value (NPV) of 50%; when middle-proximal refluxes only were considered, sensitivity decreased to 45% and specificity increased to 55%. Furthermore, the association between reflux and oesophagitis demonstrated by the chi-square (chi(2)) test proved to be statistically significant both for WST and pH monitoring, whereas the association between reflux and Barrett's oesophagus was not significant for either WST or for pH monitoring. With regard to intestinal metaplasia, WST (middle-proximal refluxes) showed higher sensitivity (64% vs. 58%) and specificity (63% vs. 51%) than pH monitoring, whereas the statistical association between reflux and metaplasia proved to be significant for WST but not for pH monitoring.

WST is a simple, inexpensive and reliable test that might be useful in the diagnosis of gastroesophageal reflux disease (GERD). A positive WST might be an additional indication for endoscopy with biopsy.