The diagnosis of gastroesophageal reflux disease.

Gastroesophageal reflux disease (GERD) is known to cause erosive esophagitis, Barrett esophagus and has been linked to the development of adenocarcinoma of the esophagus. Currently, endoscopy is the main clinical tool for visualizing esophageal lesions, but the majority of GERD patients do not have endoscopic visible lesions and other methods are required. Ambulatory esophageal pH monitoring is the gold standard in diagnosing GERD, since it measures distal esophageal acid exposure and demonstrates the relationship between symptoms and acid reflux. The effectiveness of selective gastric acid suppressive therapy led to the introduction of short trials of proton pump inhibitors (PPIs) to diagnose GERD and they are often used as a first line diagnostic tool in clinical practice and, in particular, in the primary care setting, the current trend being that gastroenterologists are asked to evaluate mainly patients with persistent GERD symptoms while on PPI therapy. In these patients the question is whether the persistent symptoms are or not associated with reflux (acid or nonacid). Recently, either combined multichannel intraluminal impedance and pH monitoring or bilimetry allow to study the mechanisms underlying the persistent symptoms on acid suppressive therapy. Manometry is mandatory prior to any surgical approach and to verify motility disorders that could be associated to GERD.