The omeprazole test is as sensitive as 24-h oesophageal pH monitoring in diagnosing gastro-oesophageal reflux disease in symptomatic patients with erosive oesophagitis

Background: Ambulatory 24-h oesophageal pH monitoring and a short course of high dose omeprazole can be used as diagnostic modalities for GERD. However, comparative studies of the diagnostic accuracy and reliability of both strategies have not been performed. Aim: To compare the omeprazole test to ambulatory 24-h oesophageal pH monitoring in diagnosing GERD in symptomatic patients using endoscopically proven erosive oesophagitis as a gold standard. Methods: Patients with heartburn underwent an upper endoscopy. Only those with erosive oesophagitis were included in the study. Subsequently, patients underwent ambulatory 24-h oesophageal pH monitoring and an 'omeprazole test.' Daily symptoms were recorded during the first week (baseline) and repeated during the second week on therapy (omeprazole 40 mg in the morning and 20 mg in the evening). Results: Thirty-five patients were included in the study. The omeprazole test was significantly more sensitive in diagnosing GERD than total acid contact time on 24-h oesophageal pH monitoring (83% vs. 60%; P < 0.03). However, the sensitivity of the pH test increased to 80% after adding patients with a positive symptom index, and patients with abnormal acid exposure in the supine or erect positions despite normal total acid contact time. Patients with a normal pH test were significantly younger (49 ± 2.6 years) than those with abnormal test (59 ± 1.8; P = 0.002). Conclusions: In this study an omeprazole test was at least as sensitive as ambulatory 24-h oesophageal pH monitoring in diagnosing GERD in patients with erosive oesophagitis.