Diagnostic assessment of gastroesophageal reflux disease: what is possible vs. what is practical?

The diagnosis of gastroesophageal reflux disease (GERD) entails the identification of patients with esophagitis and its complications as well as patients who have symptoms but no mucosal disease. Endoscopy is mandatory to establish a diagnosis of reflux esophagitis, to exclude other esophageal disease and to permit directed biopsy if columnar metaplasia, dysplasia or carcinoma is suspected. The lesions of reflux esophagitis--erosions, ulceration, stricturing and metaplasia--should be identified and graded independently, using a classification system such as the recently described "MUSE" (Metaplasia, Ulcer, Stricture, Erosions) system. Fluoroscopy can identify associated structural changes such as stricturing or esophageal shortening. Measures of esophageal acid exposure time may be used to quantify reflux before and after treatment; however, if the patient has typical symptoms but no esophagitis, a temporal association between symptoms and episodes of esophageal acidification should be sought. Ambulatory 24-hour esophageal pH-monitoring with accurate event-marking provides recordings suitable for an objective statistical analysis, which was evaluated prospectively in 14 patients. Computerized analysis of 24-hour esophageal pH recordings diagnosed 5 patients as having acid-related symptoms although only 3 of 5 patients fulfilling the criteria for pathological reflux had pH-related chest pain. This finding was confirmed by 5 experts who analyzed all recordings visually, unaware of the result of the computer analysis. The Bernstein test should be reserved for patients whose symptoms are too infrequent to permit an objective assessment of symptom occurrence during pH monitoring. In conclusion, i) endoscopy is the test of choice for the diagnosis of esophagitis but it should be supplemented by a standardized and reliable scoring system for disease severity; ii) ambulatory esophageal pH recording with accurate event-marking is the test of choice for the diagnosis of GER-related symptoms, but it should be supplemented by an objective assessment of the temporal relationship between symptoms and esophageal pH; and iii) esophageal manometry is the test of choice for evaluating esophageal peristalsis and LES (lower esophageal sphincter) function but, in the context of GERD, its main indication is the assessment of GERD patients who are being considered for surgery. The widespread use of other tests for clinical purposes must await a better understanding of the pathophysiological mechanisms which can lead to the development of GERD.