Current applications of evolving methodologies in gastroesophageal reflux disease testing

Until recently catheter-based 24-h pH monitoring has been the primary methodology for the objective diagnosis of gastroesophageal reflux disease. Yet, this system has some drawbacks, such as patient discomfort, marginal sensitivity, and the inability to detect nonacid reflux. Hampered by these limitations, several new techniques have been recently introduced in clinical practice. In particular, wireless capsule pH monitoring and multichannel intraluminal impedance-pH testing have been forwarded as more sophisticated means of enhancing patient comfort during testing as well as our ability to diagnose gastroesophageal reflux disease, especially in those patients who complain of symptoms of gastroesophageal reflux disease despite adequate acid suppression therapy. The goal of this review is to compare the clinical applicability, advantages and drawbacks of catheter-based 24-h pH testing, wireless capsule pH monitoring, and multichannel intraluminal impedance-pH.