Gene expression profiling of inflammatory cytokines in esophageal biopsies of different phenotypes of gastroesophageal reflux disease: a cross-sectional study.

BACKGROUND: The clinical endoscopic phenotypes of gastroesophageal reflux disease (GERD) are classified as Barrett's esophagus (BE), erosive esophagitis (EE) and non-erosive gastroesophageal reflux disease (NERD). NERD is subclassified as abnormal acid exposure (AAE) and normal acid exposure (NAE) based on pH monitoring study results. The aim of this study was to characterize genes involved in the pathophysiology and immune response of GERD. METHODS: This is an observational and cross-sectional study. All patients with BE, EE, AAE, and NAE and a control group were subjected to superior endoscopy (with biopsies of esophageal mucosa). Relative mRNA quantification of cytokine and target genes was conducted by quantitative Polymerase Chain Reaction (RT-qPCR). Changes in the expression of genes associated with inflammation were assessed for each disease phenotype. Statistical analysis of differential gene expression was performed using the Mann-Whitney U non-parametric test. A p value < 0.05 was considered significant. RESULTS: A total of 82 patients were included and were divided into the following groups: Group BE, 16 (19.51%); Group EE, 23 (28.04%); Group AAE, 13 (15.86%); NAE 13 (15.86%); and Control Group, 17 (20.73%). Compared with the control group, patients with BE exhibited increased IL-8 expression (p < 0.05) and increased levels of IL-10, MMP-3, and MMP-9. Patients with EE exhibited increased levels of IL-1B, IL-6 and IL-10 (p < 0.05), and patients with AAE exhibited increased expression of IL-1B, IL-6, IFN-γ and TNF-α (p < 0.05). AAE exhibited increased IL-1B and TNF-α expression compared with NAE (p < 0.05). CONCLUSION: This study demonstrates the differential expression of mediators of inflammation in the esophageal mucosa of patients with different GERD endoscopic phenotypes. IL-1B and TNF-α could be useful to differentially diagnose AAE and NAE in the non-erosive phenotype using endoscopic biopsies.

Latin American consensus on diagnosis of gastroesophageal reflux disease.

BACKGROUND: Diagnosing gastroesophageal reflux disease (GERD) can be challenging given varying symptom presentations, and complex multifactorial pathophysiology. The gold standard for GERD diagnosis is esophageal acid exposure time (AET) measured by pH-metry. A variety of additional diagnostic tools are available. The goal of this consensus was to assess the individual merits of GERD diagnostic tools based on current evidence, and provide consensus recommendations following discussion and voting by experts. METHODS: This consensus was developed by 15 experts from nine countries, based on a systematic search of the literature, using GRADE (grading of recommendations, assessment, development and evaluation) methodology to assess the quality and strength of the evidence, and provide recommendations regarding the diagnostic utility of different GERD diagnosis tools, using AET as the reference standard. KEY RESULTS: A proton pump inhibitor (PPI) trial is appropriate for patients with heartburn and no alarm symptoms, but nor for patients with regurgitation, chest pain, or extraesophageal presentations. Severe erosive esophagitis and abnormal reflux monitoring off PPI are clearly indicative of GERD. Esophagram, esophageal biopsies, laryngoscopy, and pharyngeal pH monitoring are not recommended to diagnose GERD. Patients with PPI-refractory symptoms and normal endoscopy require reflux monitoring by pH or pH-impedance to confirm or exclude GERD, and identify treatment failure mechanisms. GERD confounders need to be considered in some patients, pH-impedance can identify supragrastric belching, impedance-manometry can diagnose rumination. CONCLUSIONS: Erosive esophagitis on endoscopy and abnormal pH or pH-impedance monitoring are the most appropriate methods to establish a diagnosis of GERD. Other tools may add useful complementary information.