The Lyon Consensus: Does It Differ From the Previous Ones?

Abstract

Gastroesophageal reflux disease (GERD) is a complex disorder with heterogeneous symptoms and a multifaceted pathogenetic basis, which prevent a simple diagnostic algorithm or any categorical classification. Clinical history, questionnaires and response to proton pump inhibitor (PPI) therapy are insufficient tools to make a conclusive diagnosis of GERD and further investigations are frequently required. The Lyon Consensus goes beyond the previous classifications and defines endoscopic and functional parameters able to establish the presence of GERD. Evidences for reflux include high-grade erosive esophagitis, Barrett's esophagus, and peptic strictures at endoscopy as well as esophageal acid exposure time > 6% on pH-metry or combined pH-impedance monitoring. Even if a normal endoscopy does not exclude GERD, its combination with distal acid exposure time < 4% on off-PPI pH-impedance monitoring provides sufficient evidence refuting this diagnosis. Reflux-symptom association on pH-monitoring provides supportive evidence for reflux-triggered symptoms and may predict a better treatment outcome, when present. Also recommendations to perform pH-impedance "on" or "off" PPI are well depicted. When endoscopy and pH-metry or combined pH-impedance monitoring are inconclusive, adjunctive evidence from biopsy findings (eg, microscopic esophagitis), high-resolution manometry (ie, ineffective esophagogastric barrier and esophageal body hypomotility), and novel impedance metrics, such as mean nocturnal baseline impedance and post-reflux swallow-induced peristaltic wave index, can contribute to better identify patients with GERD. Definition of individual patient phenotype, based on the level of refluxate exposure, mechanism of reflux, efficacy of clearance, underlying anatomy of the esophagogastric junction, and clinical presentation, will lead to manage GERD patients with a tailored approach chosen among different types of therapy.

Keywords: Endoscopy; Esophagitis; Gastroesophageal reflux; Manometry; Proton pump inhibitors.

Figure 1

Time-line with the landmarks in the gastroesophageal reflux disease (GERD) assessment that have led to the Lyon Consensus. HRM, high-resolution manometry; LA, Los Angeles; RDQ, reflux disease questionnaire; GERDQ, gastroesophageal reflux disease questionnaire; PSPW-I, post-swallow reflux-induced peristaltic wave index; MNBI, mean nocturnal baseline impedance; EGJ-CI, esophagogastric junction contractile integral.

Figure 2

Indications for questionnaire and proton pump inhibitor-trial use. GERD, gastroesophageal reflux disease.

Figure 3

Interpretation of macroscopic and microscopic findings on endoscopy and role of Bilitec. GERD, gastroesophageal reflux disease; LA, Los Angeles classification; EoE, eosinophilic esophagitis.

Figure 4

Indications and interpretation of ambulatory reflux monitoring. GERD, gastroesophageal reflux disease; AET, acid exposure time; NRE, number reflux episodes; PPI, proton pump inhibitor; MII-pH, combined pH and intraluminal impedance monitoring; LA, Los Angeles classification; EE, extra-esophageal; ARS, anti-reflux surgery; SI, symptoms index; SAP, symptom association probability; MNBI, mean nocturnal baseline impedance; PSPW, post-swallow reflux-induced peristaltic wave.

Figure 5

Characterization and interpretation of motor findings in gastroesophageal reflux disease (GERD) patients. EGJ, esophagogastric junction; CI, contractile integral.

Figure 6

Esophageal test results in gastroesophageal reflux disease (GERD) assessment. PPI, proton pump inhibitor; HRM, high-resolution manometry; NERD, nonerosive reflux disease; LA, Los Angeles classification; AET, acid exposure time; SI, symptom index; SAP, symptom association probability; MNBI, mean nocturnal baseline impedance; PSPW, post-swallow reflux-induced peristaltic wave; EGJ, esophagogastric junction; CI, contractile integral.