[Modern Diagnostic Strategies for Gastroesophageal Reflux Disease: Focus on Lyon Consensus 2.0]

The diagnosis of gastroesophageal reflux disease (GERD) has evolved from a symptom-based approach to an objective test-based strategy. Lyon consensus 2.0 provides updated criteria for classifying GERD as conclusive or inconclusive and proposes differential diagnostic strategies based on prior GERD evidence and symptom presentation. Recent evidence incorporated into Lyon consensus 2.0 was reviewed with emphasis on actionable GERD, unproven versus proven GERD, updated endoscopic criteria, prolonged wireless pH monitoring, ambulatory pH-impedance monitoring, and adjunctive reflux metrics. Lyon consensus 2.0 defines actionable GERD as a condition in which objective esophageal testing supports revising, escalating, or personalizing management in symptomatic patients. Major updates include recognizing Los Angeles grade B esophagitis as conclusive evidence of GERD, preferring prolonged wireless pH monitoring for unproven GERD with typical symptoms, and use of on-therapy pH-impedance monitoring in proven GERD with persistent symptoms. The acid exposure time remains the primary reflux metric, while the number of reflux episodes and mean nocturnal baseline impedance serve as adjunctive parameters. In contrast, the postreflux swallow-induced peristaltic wave index has been retired from the core diagnostic framework. Lyon consensus 2.0 refines modern GERD diagnosis by integrating symptom phenotype, prior objective evidence, and context-specific reflux testing. Its main clinical value lies in personalizing diagnostic strategies and improving confidence in treatment-related decision-making.