Acid and non-acid reflux in patients with persistent symptoms despite acid suppressive therapy: a multicentre study using combined ambulatory impedance-pH monitoring

Pepsin, Mucosal Injury, and Pathophysiology of Non-acid Reflux

The gastric enzyme pepsin is a critically under-addressed aggressor during reflux disease and is regarded by many as the most damaging element of laryngopharyngeal reflux. Research over the last 2 decades has elucidated mechanisms by which pepsin causes damage during weakly and nonacid reflux yielding information to exploit its diagnostic and therapeutic potential. These findings have driven advances that, while still in their infancy, harbor important clinical implications.

Update on laryngopharyngeal reflux disease

PURPOSE OF REVIEW

Chronic laryngopharyngeal symptoms (LPS) are increasingly prevalent presentations to gastroenterologists' offices, and clinicians often make a presumptive diagnosis of laryngopharyngeal reflux disease (LPRD) based on LPS symptoms or laryngoscopic findings alone. Such presumptive diagnoses of LPRD often are incorrect, and establishing the correct diagnosis poses significant challenges for clinicians. This review addresses the timely need for advances in evaluating and managing LPS/LPRD, given their diagnostic complexity and the healthcare burden of ineffective empiric treatments.

RECENT FINDINGS

Recent evidence emphasizes the diverse etiologies of LPS including LPRD, oropharyngeal or other airway pathologies, allergic conditions, and cognitive-affective processes or altered brain-larynx interaction. The diagnostic approach should be individualized and multimodal, including upfront reflux testing over empiric acid suppression trials for possible LPRD, given the poor correlation between LPS and objective evidence of reflux. Predictive models and risk stratification tools such as the COuGH RefluX score show promise to help guide testing and therapeutic strategies. Reflux testing modalities include wireless pH monitoring and impedance-based testing (traditional impedance-pH or combined hypopharyngeal-esophageal reflux monitoring). Biochemical testing for salivary pepsin may also offer adjunctive value. Management should include antireflux strategies for those with objectively-proven LPRD, alongside treatments targeting nonreflux mechanisms of LPS, such as voice therapy, neuromodulation, and behavioral therapy.

SUMMARY

An individualized, multidisciplinary approach is essential in managing LPS/LPRD. Objective reflux testing improves diagnostic accuracy, avoids unnecessary therapies, and enables tailored treatment. Future research should further refine diagnostic thresholds, validate risk stratification tools, and explore novel therapeutic targets to optimize outcomes.

The Lactulose Breath Test Can Predict Refractory Gastroesophageal Reflux Disease by Measuring Bacterial Overgrowth in the Small Intestine

OBJECTIVE

The diagnosis of RGERD in patients typically involves 24-hour esophageal pH monitoring, but due to its invasiveness and low patient compliance, new screening methods are needed. In this study, a lactulose breath test (LBT) was conducted to detect the growth of small intestine bacteria (SIBO) and explore the potential relationship between LBT and RGERD to identify a new treatment method for RGERD.

METHODS

A total of 178 patients with gastroesophageal reflux were enrolled from June 2020 to December 2022 in the Gastroenterology Department, Building 3, the First Affiliated Hospital of Kunming Medical University; these patients included 96 patients with nonrefractory GERD (NRGERD) and 82 patients with RGERD. The Gerd Q score, reflux symptom index (RSI) score, gastroscopy results, clinical symptoms, and other related indicators were collected. Statistical methods were used to analyze the gathered data.

RESULTS

The incidence of acid reflux and heartburn in patients with RGERD was significantly greater than that in patients with NRGERD (67.10% vs. 42.70%, P <0.01 and 65.00% vs. 34.40%, P <0.01). The CH 4 values of patients with RGERD were significantly greater than those of patients with NRGERD at each time point, and there was a correlation between the CH 4 values at 60 min and RGERD ( P <0.05). For patients with RGERD, the incidence of abdominal pain, acid regurgitation, and heartburn was greater in the CH 4 -positive group than in the CH 4 -negative group (61.90% vs. 57.50%, 69.05% vs. 65.00%, 69.05% vs. 57.50%, P >0.05). The incidence of nausea was also greater in the CH 4 -positive group than in the CH 4 -negative group (61.90% vs. 35.00%, P <0.05).

CONCLUSION

Increased CH 4 levels are correlated with RGERD. In addition, patients with RGERD may develop SIBO after long-term use of PPIs, and interventions involving SIBO could provide new ideas for the treatment of RGERD.

Extraesophageal reflux: Clinical manifestations and tools for diagnosis and treatment

Extraesophageal reflux is a complex clinical entity, classically presenting with laryngopharyngeal symptoms including chronic cough and vocal changes, but it is also implicated in conditions such as subglottic stenosis and lung injury. Diagnosis is challenging, in large part due to the oftentimes vague presenting symptoms with multiple possible etiologies, as well as limited consistency of currently available diagnostic tests. Furthermore, effective medical treatment is limited, and acid suppression therapy such as proton pump inhibitors has shown low to mixed efficacy in relieving signs and symptoms of reflux outside the esophagus. In this review, we will address laryngopharyngeal reflux and its diagnosis based on symptoms and exam findings, and diagnostic tools such as impedance monitoring and salivary pepsin testing. A summary of the use and limitations of acid-suppressing therapies for extraesophageal reflux and the rationale for targeting pepsin as a nonacid component of reflux will be presented. Finally, the current literature on the potential role of reflux in subglottic stenosis and lessons learned regarding reflux in the lung transplant surgery field in higher risk patient populations will be discussed.

Update Motility Disorders: Gastro-Oesophageal Reflux Disease - Diagnostic and Conservative Approach

Background

Gastro-oesophageal reflux disease (GORD) is extremely common, with at least 1 in 10 people in the general population reporting heartburn and acid regurgitation on a weekly basis. GORD can also be associated with a variety of atypical symptoms, including chest pain, chronic cough, and laryngopharyngeal symptoms. The causes of GORD are multifactorial, and the severity of symptoms is influenced by peripheral and central factors, including psychosocial stress and anxiety. Therefore, for a variety of reasons, no single investigation provides a definitive diagnosis, and standard treatment with acid suppressants is not always effective.

Summary

This review introduces the Lyon Consensus, now in its second iteration, a classification system that provides a "conclusive" positive or negative diagnosis of GORD by integrating the results of endoscopy, ambulatory reflux monitoring, and high-resolution manometry. Different algorithms are applied to patients with high and low pre-test probability of a causal relationship between reflux episodes and patient symptoms. The results of these studies identify patients with "actionable" results that require escalation, revision, or discontinuation of GORD treatment. Guidance is provided on the range of conservative treatments available for GORD, including dietary and lifestyle advice, antacids and alginates, and drugs that suppress acid secretion.

Key Messages

GORD is a common disorder; however, the causes of reflux and symptoms can be complex. As a result, the diagnosis can be missed, and management is sometimes challenging, especially for patients with atypical symptoms. The Lyon classification establishes a conclusive diagnosis of GORD, based on results of endoscopic and physiological investigation. Typical symptoms usually respond to empiric use of alginate-antacid preparations and acid suppression; however, the management of treatment refractory symptoms is tailored to the individual.

Advances in laryngopharyngeal reflux: Etiology, diagnosis, and management

Laryngopharyngeal reflux (LPR) manifests as a variety of nonspecific upper aerodigestive tract symptoms. Rather than a single disorder, LPR may be conceived of as a spectrum of subtypes with varying clinical presentations. LPR signs and symptoms arise from the direct and/or indirect effects of refluxate, physical and molecular injury of the mucosa, and neurologic responses to esophageal events. Specific constituents of refluxate exert distinct mucosal responses and immediate or delayed effects resulting in transient or persistent symptoms and/or laryngeal hypersensitivity. While the complex etiology of LPR presents challenges to its diagnosis and management, tools that aid the identification of LPR subtypes can provide insight into treatment decision-making. Hypopharyngeal-esophageal multichannel intraluminal impedance-pH monitoring provides detailed analysis of reflux events, enabling the development of individualized treatment plans, yet cost and availability limit its widespread use. Alginates offer temporary symptom relief and antireflux surgery may provide benefit when symptoms are recalcitrant to other approaches. Pepsin inhibitors hold promise as a medical therapy when surgery is not an option. Laryngeal hypersensitivity should be considered as part of a comprehensive therapeutic approach. Promising medical and scientific research continues to yield new insights into the complex etiology of LPR and novel strategies for its diagnosis and management.

Significant and distinct impacts of sleeve gastrectomy and Roux-en-Y gastric bypass on esophageal acid exposure, esophageal motility, and endoscopic findings: a systematic review and meta-analysis

BACKGROUND

The lack of standardized objective assessment of esophageal physiology and anatomy contributes to controversies regarding the effects of sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) on gastroesophageal reflux disease. This study aimed to investigate esophageal acid exposure, esophageal motility, and endoscopic findings before and after SG and RYGB.

METHODS

This was a systematic review and meta-analysis of studies reporting at least 1 objective measure of esophageal physiology and/or esophagogastroduodenoscopy (EGD) at baseline and after SG or RYGB. The changes in pH test, manometry, and EGD parameters were summarized.

RESULTS

Acid exposure time (AET) and DeMeester score (DMS) significantly increased after SG (mean difference [MD]: 2.1 [95% CI, 0.3-3.9] and 8.6 [95% CI, 2.0-15.2], respectively). After RYGB, both AET and DMS significantly decreased (MD: -4.2 [95% CI, -6.1 to -2.3] and -16.6 [95% CI, -25.4 to -7.8], respectively). Lower esophageal sphincter resting pressure and length significantly decreased after SG (MD: -2.8 [95% CI, -4.6 to -1.1] and -0.1 [95% CI, -0.2 to -0.02], respectively). There were no significant changes in esophageal manometry after RYGB. The relative risks of erosive esophagitis were 2.3 (95% CI, 1.5-3.5) after SG and 0.4 (95% CI, 0.2-0.8) after RYGB. The prevalence rates of Barrett esophagus changed from 0% to 3.6% after SG and from 2.7% to 1.4% after RYGB.

CONCLUSION

SG resulted in the worsening of all objective parameters, whereas RYGB resulted in the improvement in AET, DMS, and EGD findings. Determining the risk factors associated with these outcomes can help in surgical choice.

A scientometrics analysis and visualization of refractory gastroesophageal reflux disease

Background

Refractory gastroesophageal reflux disease (refractory GERD) is a heterogeneous disease characterized by unresponsiveness or poor efficacy to proton-pump inhibitors (PPIs). This chronic disorder substantially weakens patients' mental wellbeing and quality of life, increasing the financial burden on society. Multiple articles have been reported in this area. However, literature involving scientometric analysis of refractory GERD is absent. Therefore, it is necessary to understand the evolution of research themes and the main hotspots of refractory GERD through bibliometric methods.

Methods

All documents related to refractory GERD based on the WOS Core Collection from January 2000 to November 2023 were selected for analysis. Citespace V 6.1 R6, VOSviewer V 1.6.20, and Scimago Graphica V 1.0.38 were used to perform bibliometric analysis.

Results

We collected a total of 241 research articles from 36 countries and 322 institutions, contributed by over 1,000 authors. Over the last 20 years, the number of articles in this field has increased year by year, and since 2011, the number of publications has increased dramatically, with 85.89% of the papers. These countries are led by the United States and Japan. GUT had the highest number of citations and DIGESTION had the highest number of publications. Research on standardized diagnosis and management, mechanisms, novel monitoring methods, and innovative drugs and procedures for refractory GERD are the main topics and hotspots in this field. This study also found that neuroimmune interaction is closely related to refractory GERD, which may be a new direction for future mechanism research.

Conclusion

Our study is the first bibliometric analysis of the global literature on refractory GERD. This research provides valuable insights for researchers, enabling them to quickly understand the research frontier and hot topics of this field.

Update on extraesophageal manifestations of gastroesophageal reflux

PURPOSE OF REVIEW

Symptoms/complications related to extraesophageal reflux (EER) are increasingly prevalent presentations and pose significant challenges for clinicians. We summarize and discuss clinical advances and developments in pathophysiology, testing and treatment algorithms of upper/lower airway manifestations of EER.

RECENT FINDINGS

Growing evidence supports likely multifactorial causes of laryngeal symptoms, including EER, oropharyngeal pathologies, allergic conditions, and cognitive-affective processes (brain-larynx interaction). Diagnostic paradigm for laryngopharyngeal reflux (LPR) is shifting towards a personalized approach with noninvasive strategies/prediction tools to risk-stratify patients for upfront reflux testing over empiric acid suppression trials. Management should be multipronged to include antireflux therapies and treatments targeting other causes. Lower airway complications of EER may result in lung dysfunction and poor transplant outcomes. Esophageal symptoms are often absent and routine esophageal/reflux testing to guide timely antireflux therapies may lead to improved outcomes. Modalities that leverage impedance technology may be important, given the potential role of nonacidic reflux. Novel impedance-based metrics such as mean nocturnal baseline impedance and postreflux swallow-induced peristaltic wave index may provide adjunctive diagnostic values.

SUMMARY

Standardized approach to diagnosis/management of EER should include multidisciplinary care teams and consider different phenotypes, nonreflux contributors, and the complex gut-airway relationships. Prompt antireflux therapies after careful candidate selection may improve outcomes of these airway complications.

How to diagnose GERC more effectively: reflections on post-reflux swallow-induced peristaltic wave index and mean nocturnal baseline impedance

INTRODUCTION

Post-reflux swallow-induced peristaltic wave index (PSPWI) and mean nocturnal baseline impedance (MNBI) are novel parameters reflect esophageal clearance capacity and mucosal integrity. They hold potential in aiding the recognition of gastroesophageal reflux-induced chronic cough (GERC). Our study aims to investigate their diagnostic value in GERC.

METHODS

This study included patients suspected GERC. General information and relevant laboratory examinations were collected, and final diagnosis were determined following guidelines for chronic cough. The parameters of multichannel intraluminal impedance-pH monitoring (MII-pH) in patients were analyzed and compared to explore their diagnostic value in GERC.

RESULTS

A total of 186 patients were enrolled in this study. The diagnostic value of PSPWI for GERC was significant, with the area under the working curve (AUC) of 0.757 and a cutoff value of 39.4%, which was not statistically different from that of acid exposure time (AET) (p > 0.05). The combined diagnostic value of AET > 4.4% and PSPWI < 39.4% was superior to using AET > 4.4% alone (p < 0.05). Additionally, MNBI and distal MNBI also contributed to the diagnosis of GERC, with AUC values of 0.639 and 0.624, respectively. AET > 4.4% or PSPWI < 39.4% is associated with a 44% reduction in missed diagnoses of non-acid GERC compared to AET > 6.0% or symptom association probability (SAP) ≥ 95%, and may be more favorable for identifying GERC.

CONCLUSION

The diagnostic value of PSPWI for GERC is comparable to that of AET. Combining PSPWI < 39.4% or AET > 4.4% can improve the diagnostic efficiency by reducing the risk of missed diagnoses in cases where non-acid reflux is predominant. Distal MNBI and MNBI can serve as secondary reference indices in the diagnosis of GERC.

Chronic Cough and Obstructive Sleep Apnea

Chronic cough, defined as a cough lasting more than 8 weeks, is a common medical condition occurring in 5% to 10% of the population. Its overlap with another highly prevalent disorder, obstructive sleep apnea (OSA), is therefore not surprising. The relationship between chronic cough and OSA extends beyond this overlap with higher prevalence of OSA in patients with chronic cough than in the general population. The use of continuous positive airway pressure can result in improvement in chronic cough although further studies are needed to understand which patients will experience benefit in their cough from the treatment of comorbid OSA.

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.

Multichannel intraesophageal impedance with pH metry in Saudi children

BACKGROUND

Multichannel Intraesophageal Impedance with pH (MII-pH) provides complete characterization of gastroesophageal reflux (GER). The aim of this study was to report our experience in this relatively new technique, emphasizing the challenges in the performance and interpretation of the results.

METHODS

The study was conducted at King Khalid University Hospital at King Saud University in Riyadh. A retrospective review of the medical records of children who underwent MII-pH was performed. The procedure was performed and interpreted according to the recommended methodology. The impedance catheter was introduced nasally. The use of event markers and diary were explained to the accompanying person. At the end of the recording, the data were downloaded to the software analysis system.

RESULTS

MII-pH was performed on 98 children, and 16 studies were excluded from analysis for technical reasons. The median age was 32 (range 2-168) months and 44 (54%) were male. The prevalence of nonacid gastroesophageal reflux (NAGER), proximal extent of GER, and postprandial NAGER were 55%, 50%, and 70%, respectively. One hundred and fifty-three symptoms were reported during the study, but only two were significant.

CONCLUSION

The MII-pH was well-tolerated but the performance and interpretation were technically demanding. The main advantage was the detection of NAGER. However, the lack of normal values and the reliance on symptom association make the interpretation of the results challenging.

Investigation of the Relationship Between Laparoscopic Sleeve Gastrectomy and Gastroesophageal Reflux Disease Using 24-hour Multichannel Intraluminal Impedance With pH Testing According to Current Consensus

BACKGROUND

Laparoscopic sleeve gastrectomy (LSG) is a popular weight loss procedure with potential effects on gastroesophageal reflux disease (GERD). However, research on the association between LSG and GERD using objective evaluation criteria, such as multichannel intraluminal impedance combined with pH testing (MII-pH), is limited. This study aimed to investigate the impact of LSG on GERD using MII-pH and current consensus guidelines.

MATERIALS AND METHODS

It was conducted as a prospective clinical study on 33 patients who underwent LSG between January 2022 and August 2022. MII-pH and high-resolution manometry were performed preoperatively and 3 to 6 months postoperatively. GERD diagnosis was based on MII-pH results using the Lyon and Update Porto consensus guidelines.

RESULTS

Postoperative MII-pH analysis revealed a significant increase in acid reflux time, acid exposure time, reflux index, esophageal clearance, total reflux time, and longest reflux period. Weak acid reflux episodes decreased, while Demeester score and alkaline reflux showed nonsignificant increases. Pathologic reflux significantly increased postoperatively based on MII-pH diagnosis. High-resolution manometry showed a significant increase in unsuccessful motility.

CONCLUSION

Although the Demeester score calculation consists of 6 metrics, including acid exposure time, the acid exposure time is more specific in detecting pathologic reflux. Pathologic GERD increases significantly with LSG in the early period. Therefore, preoperative and postoperative endoscopy and MII-pH can provide valuable information regarding the need for closer follow-up after LSG.

Inhaled fosamprenavir for laryngopharyngeal reflux: Toxicology and fluid dynamics modeling

Objectives

Approximately 25% of Americans suffer from laryngopharyngeal reflux (LPR), a disease for which no effective medical therapy exists. Pepsin is a predominant source of damage during LPR and a key therapeutic target. Fosamprenavir (FOS) inhibits pepsin and prevents damage in an LPR mouse model. Inhaled FOS protects at a lower dose than oral; however, the safety of inhaled FOS is unknown and there are no inhalers for laryngopharyngeal delivery. A pre-Good Lab Practice (GLP) study of inhaled FOS was performed to assess safety and computational fluid dynamics (CFD) modeling used to predict the optimal particle size for a laryngopharyngeal dry powder inhaler (DPI).

Methods

Aerosolized FOS, amprenavir (APR), or air (control) were provided 5 days/week for 4 weeks (n = 6) in an LPR mouse model. Organs (nasal cavity, larynx, esophagus, trachea, lung, liver, heart, and kidney) were assessed by a pathologist and bronchoalveolar lavage cytokines and plasma cardiotoxicity markers were assessed by Luminex assay. CFD simulations were conducted in a model of a healthy 49-year-old female.

Results

No significant increase was observed in histologic lesions, cytokines, or cardiotoxicity markers in FOS or APR groups relative to the control. CFD predicted that laryngopharyngeal deposition was maximized with aerodynamic diameters of 8.1-11.5 μm for inhalation rates of 30-60 L/min.

Conclusions

A 4-week pre-GLP study supports the safety of inhaled FOS. A formal GLP assessment is underway to support a phase I clinical trial of an FOS DPI for LPR.

Level of Evidence

NA.

Post-reflux swallow-induced peristaltic wave index: a new parameter for the identification of non-acid gastroesophageal reflux-related chronic cough

BACKGROUND

The current available diagnostic criteria for gastroesophageal reflux-related chronic cough (GERC) dominated by non-acid reflux is imperfect. The post-reflux swallow-induced peristaltic wave index (PSPWI) is a parameter reflecting esophageal clearance function.

OBJECTIVES

This study aims to investigate its diagnostic value for non-acid GERC.

DESIGN

This study sought to compare the diagnostic value of PSPWI in different types of GERC, particularly non-acid GERC, and explore the clinical significance of PSPWI in the diagnosis of non-acid GERC through diagnostic experiments.

METHODS

A retrospective analysis was performed based on 223 patients with suspected GERC who underwent multichannel intraluminal impedance-pH monitoring (MII-pH) in the outpatient clinic of our department from August 2016 to June 2021. Their clinical information, laboratory test results, and treatment responses were assessed and the underlying etiologies of chronic cough were categorized. The predictive value of the PSPWI in diagnosing different types of GERC, especially non-acid GERC, was analyzed and compared.

RESULTS

A total of 195 patients with chronic cough who met the inclusion criteria underwent MII-pH monitoring. 143 patients had a definitive diagnosis of GERC, including 98 with acid GERC and 45 with non-acid GERC. The diagnostic value of PSPWI alone was moderate for GERC with an area under the working curve (AUC) 0.760, but poor for non-acid GERC with an AUC of 0.569. However, PSPWI < 39.8% combining with acid exposure time (AET) ⩽ 6.2% demonstrated a moderate diagnostic value for non-acid GERC, with an AUC of 0.722. When PSPWI < 39.8% combined with a non-acid reflux ratio >68.75%, the diagnostic value for non-acid GERC was improved (AUCROC = 0.80 versus AUCROC = 0.722, p < 0.05), which was significantly superior to non-acid symptom index (AUCROC = 0.804 versus AUCROC = 0.550, p < 0.05) and non-acid symptom association probability (AUCROC = 0.804 versus AUCROC = 0.571, p < 0.05).

CONCLUSION

PSPWI < 39.8% and AET ⩽ 6.2% have demonstrated good diagnostic value for non-acid GERC. The diagnostic value was further improved when combined with non-acid reflux ratio >68.75%.

Optimizing ambulatory reflux monitoring: current findings and future directions

INTRODUCTION

Gastroesophageal reflux disease (GERD) is the most common diagnosis seen in outpatient gastroenterology clinics. The diagnosis is made by a variable combination of symptoms, response to acid suppressive therapy, endoscopic evaluation, and pH testing. In this review, we evaluate how to utilize various reflux testing in clinical practice based on current evidence.

AREAS COVERED

Ambulatory reflux monitoring is a recognized diagnostic tool for clinical decision making in patients with/without established GERD, persistent reflux symptoms, and lack of response to proton pump inhibitor (PPI) therapy. Standard evaluation approaches include 24-hour pH or impedance monitoring via transnasal catheter, prolonged (48 to 96 hour) wireless pH monitoring, and the recently developed mucosal integrity testing. Testing using one of these methods allows for measurement of acid exposure, frequency of reflux, and to phenotype patients to personalize treatment recommendations.

EXPERT OPINION

The primary goal of future studies should be to simplify ambulatory reflux monitoring, reduce diagnostic latency, improve patient tolerance, and to obtain clinical outcomes-based studies. The current paradigm of reflux testing is vastly complex with multiple modalities and shifting cutoffs of pH abnormality that lead to high economic burden on the society.

A perspective on the clinical relevance of weak or nonacid reflux

BACKGROUND

Advances in ambulatory esophageal reflux monitoring that incorporated impedance electrodes to pH catheters have resulted in better characterization of retrograde bolus flow in the esophagus. With pH-impedance monitoring, in addition to acid reflux episodes identified by pH drops below 4.0, weakly acid reflux (WAR, pH 4-7) and nonacid reflux (NAR, pH >7.0) are also recognized, although both may be included under the umbrella term NAR. However, despite identification of ambulatory pH-impedance monitoring, data on clinical relevance and prognostic value of NAR are limited. The Lyon Consensus, an international expert review that defines conclusive metrics for gastroesophageal reflux disease (GERD), identifies NAR as "supportive" but not conclusive for GERD.

PURPOSE

This review provides perspectives on whether NAR fulfills three criteria for clinical relevance: whether NAR sufficiently explains pathogenesis of symptoms, whether it is associated with meaningful manifestations of GERD, and whether it can predict treatment efficacy.

The Real Relevance of Nonacid Reflux in Pediatric Patients

Gastroesophageal reflux (GER) is one of the most common presenting complaints to pediatric gastroenterologists, and a wide variety of symptoms in children are potentially attributable to typical or atypical GER. While reflux diagnosis and treatment paradigms classically have focused on targeting acid, there is a growing recognition of the prevalence and significance of nonacid GER in both children and adults. This review explores the role of nonacid reflux in pediatric patients, including definitions, associations with symptoms, pathophysiologic mechanisms, and treatment implications.

Amprenavir inhibits pepsin-mediated laryngeal epithelial disruption and E-cadherin cleavage in vitro

Background

Laryngopharyngeal reflux (LPR) causes chronic cough, throat clearing, hoarseness, and dysphagia and can promote laryngeal carcinogenesis. More than 20% of the US population suffers from LPR and there is no effective medical therapy. Pepsin is a predominant source of damage during LPR which disrupts laryngeal barrier function potentially via E-cadherin cleavage proteolysis and downstream matrix metalloproteinase (MMP) dysregulation. Fosamprenavir (FDA-approved HIV therapeutic and prodrug of amprenavir) is a pepsin-inhibiting LPR therapeutic candidate shown to rescue damage in an LPR mouse model. This study aimed to examine amprenavir protection against laryngeal monolayer disruption and related E-cadherin proteolysis and MMP dysregulation in vitro.

Methods

Laryngeal (TVC HPV) cells were exposed to buffered saline, pH 7.4 or pH 4 ± 1 mg/mL pepsin ± amprenavir (10-60 min). Analysis was performed by microscopy, Western blot, and real time polymerase chain reaction (qPCR).

Results

Amprenavir (1 μM) rescued pepsin acid-mediated cell dissociation (p < .05). Pepsin acid caused E-cadherin cleavage indicative of regulated intramembrane proteolysis (RIP) and increased MMP-1,3,7,9,14 24-h postexposure (p < .05). Acid alone did not cause cell dissociation or E-cadherin cleavage. Amprenavir (10 μM) protected against E-cadherin cleavage and MMP-1,9,14 induction (p < .05).

Conclusions

Amprenavir, at serum concentrations achievable provided the manufacturer's recommended dose of fosamprenavir for HIV, protects against pepsin-mediated cell dissociation, E-cadherin cleavage, and MMP dysregulation thought to contribute to barrier dysfunction and related symptoms during LPR. Fosamprenavir to amprenavir conversion by laryngeal epithelia, serum and saliva, and relative drug efficacies in an LPR mouse model are under investigation to inform development of inhaled formulations for LPR.

Paradoxical association between dyspepsia and autoimmune chronic atrophic gastritis: Insights into mechanisms, pathophysiology, and treatment options

BACKGROUND

Autoimmune gastritis (AIG) is a progressive, chronic, immune-mediated inflammatory disease characterized by the destruction of gastric parietal cells leading to hypo/anacidity and loss of intrinsic factor. Gastrointestinal symptoms such as dyspepsia and early satiety are very common, being second in terms of frequency only to anemia, which is the most typical feature of AIG.

AIM

To address both well-established and more innovative information and knowledge about this challenging disorder.

METHODS

An extensive bibliographical search was performed in PubMed to identify guidelines and primary literature (retrospective and prospective studies, systematic reviews, case series) published in the last 10 years.

RESULTS

A total of 125 records were reviewed and 80 were defined as fulfilling the criteria.

CONCLUSION

AIG can cause a range of clinical manifestations, including dyspepsia. The pathophysiology of dyspepsia in AIG is complex and involves changes in acid secretion, gastric motility, hormone signaling, and gut microbiota, among other factors. Managing dyspeptic symptoms of AIG is challenging and there are no specific therapies targeting dyspepsia in AIG. While proton pump inhibitors are commonly used to treat dyspepsia and gastroesophageal reflux disease, they may not be appropriate for AIG. Prokinetic agents, antidepressant drugs, and non-pharmacological treatments may be of help, even if not adequately evidence-based supported. A multidisciplinary approach for the management of dyspepsia in AIG is recommended, and further research is needed to develop and validate more effective therapies for dyspepsia.

Turnkey algorithmic approach for the evaluation of gastroesophageal reflux disease after bariatric surgery

Bariatric surgeries are often complicated by de-novo gastroesophageal reflux disease (GERD) or worsening of pre-existing GERD. The growing rates of obesity and bariatric surgeries worldwide are paralleled by an increase in the number of patients requiring post-surgical GERD evaluation. However, there is currently no standardized approach for the assessment of GERD in these patients. In this review, we delineate the relationship between GERD and the most common bariatric surgeries: sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB), with a focus on pathophysiology, objective assessment, and underlying anatomical and motility disturbances. We suggest a stepwise algorithm to help diagnose GERD after SG and RYGB, determine the underlying cause, and guide the management and treatment.

Potential therapeutic benefit of ursodeoxycholic acid in the management of non hepato-biliary upper gastrointestinal disorders

OBJECTIVES

To examine the potential therapeutic effects of ursodeoxycholic acid (UDCA) on diseases of the esophagus, stomach, and duodenum.

METHODS

A search was conducted using EBSCO, Medline, PubMed, Google Scholar and Web of Science as well as international guidelines using MESH terms for treatment of UDCA for diseases of the upper gastrointestinal disorders in adult humans without regard to publication language or date restrictions.

RESULTS

A total of 256 articles and 22 guidelines were initially identified, and 221 were excluded. Final revision of 13 articles and 22 guidelines confirmed that UDCA is found to have a cytoprotective role in Barret's esophagus within esophageal disorders, improves abdominal pain in functional dyspepsia, and does not alter Helicobacter pylori colonization or inflammation. Conflicting results are noted regarding the role of UDCA in the duodenum as chemopreventive treatment for familial adenomatous polyposis, with polyps regressing and their growth characteristics improving with low doses (10-25 mg/kg/day). On the contrary, no positive effect was noted upon the combination with Celecoxib and with doses of 1000-2000 mg or 20-30 mg/kg/d. Gastrointestinal side effects were predominantly reported. No side effects necessitated hospitalization or ICU admission.

CONCLUSION

Ursodeoxycholic acid has a limited therapeutic role in functional dyspepsia. There is promising evidence that it may serve as a chemopreventive for Familial adenomatous polyposis and Barret's esophagus, although further research is needed to confirm these findings.PROSPERO No.: CRD 42021267689.

Topical Alginate Protection against Pepsin-Mediated Esophageal Damage: E-Cadherin Proteolysis and Matrix Metalloproteinase Induction

Epithelial barrier dysfunction is a hallmark of gastroesophageal reflux disease (GERD) related to symptom origination, inflammatory remodeling and carcinogenesis. Alginate-based antireflux medications were previously shown to topically protect against peptic barrier disruption, yet the molecular mechanisms of injury and protection were unclear. Herein, Barrett's esophageal (BAR-T) cells were pretreated with buffered saline (HBSS; control), dilute alginate medications (Gaviscon Advance or Gaviscon Double Action, Reckitt Benckiser), a viscosity-matched placebo, or ADAM10 and matrix metalloproteinase (MMP) inhibitors before exposure to HBSS pH7.4 or pH4 ± 1 mg/mL pepsin for 10-60 min. Cell viability was assessed by ATP assay; mediators of epithelial integrity, E-cadherin, ADAM10, and MMPs were examined by Western blot and qPCR. Alginate rescued peptic reduction of cell viability (p < 0.0001). Pepsin-pH4 yielded E-cadherin fragments indicative of regulated intramembrane proteolysis (RIP) which was not rescued by inhibitors of known E-cadherin sheddases. Transcriptional targets of E-cadherin RIP fragments were elevated at 24 h (MMP-1,2,9,14; p < 0.01). Alginate rescued E-cadherin cleavage, ADAM10 maturation, and MMP induction (p < 0.01). Results support RIP as a novel mechanism of peptic injury during GERD. Alginate residue after wash-out to mimic physiologic esophageal clearance conferred lasting protection against pepsin-induced molecular mechanisms that may exacerbate GERD severity and promote carcinogenesis in the context of weakly acidic reflux.

The Protease Inhibitor Amprenavir Protects against Pepsin-Induced Esophageal Epithelial Barrier Disruption and Cancer-Associated Changes

Gastroesophageal reflux disease (GERD) significantly impacts patient quality of life and is a major risk factor for the development of Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC). Proton pump inhibitors (PPIs) are the standard-of-care for GERD and are among the most prescribed drugs in the world, but do not protect against nonacid components of reflux such as pepsin, or prevent reflux-associated carcinogenesis. We recently identified an HIV protease inhibitor amprenavir that inhibits pepsin and demonstrated the antireflux therapeutic potential of its prodrug fosamprenavir in a mouse model of laryngopharyngeal reflux. In this study, we assessed the capacity of amprenavir to protect against esophageal epithelial barrier disruption in vitro and related molecular events, E-cadherin cleavage, and matrix metalloproteinase induction, which are associated with GERD severity and esophageal cancer. Herein, weakly acidified pepsin (though not acid alone) caused cell dissociation accompanied by regulated intramembrane proteolysis of E-cadherin. Soluble E-cadherin responsive matrix metalloproteinases (MMPs) were transcriptionally upregulated 24 h post-treatment. Amprenavir, at serum concentrations achievable given the manufacturer-recommended dose of fosamprenavir, protected against pepsin-induced cell dissociation, E-cadherin cleavage, and MMP induction. These results support a potential therapeutic role for amprenavir in GERD recalcitrant to PPI therapy and for preventing GERD-associated neoplastic changes.

Mean Nocturnal Baseline Impedance (MNBI) Provides Evidence for Standardized Management Algorithms of Nonacid Gastroesophageal Reflux-Induced Chronic Cough

BACKGROUND

The clinical management of nonacid gastroesophageal reflux-induced chronic cough (GERC) is challenging, and patient response to standard antireflux therapy (omeprazole 20 mg twice daily plus mosapride 10 mg thrice daily) is suboptimal. This study aimed to identify predictors of standard antireflux therapy efficacy and provide evidence for standardized management algorithms of nonacid GERC.

METHODS

A total of 115 nonacid GERC patients who underwent multichannel intraluminal impedance-pH monitoring (MII-pH) were enrolled between March 2017 and March 2021. Retrospective analysis of general information and MII-pH indications were used to establish a regression analysis model for multiple factors affecting standard antireflux therapy efficacy.

RESULTS

90 patients met the inclusion criteria, and the overall response rate to standard antireflux therapy was 55.5% (50/90). The mean nocturnal baseline impedance (MNBI) (1817.75 ± 259.26 vs. 2369.93 ± 326.35, P = 0.030) and proximal MNBI (1833.39 ± 92.16 vs. 2742.57 ± 204.64, P ≤ 0.001) of responders were lower than those of nonresponders. Weakly acid reflux (56.00 (31.70, 86.00) vs. 14.00 (14.00, 44.20), P = 0.022), nonacid reflux (61.35 (15.90.86.50) vs. 21.60 (0.00, 52.50), P = 0.008), and proximal extent (19.00 (5.04, 24.00) vs. 5.50 (2.56, 11.13), P = 0.011) were markedly higher in responders than nonresponders. Proximal MNBI (OR = 0.997, P = 0.042, and optimal cutoff = 2140 Ω) and weakly acid reflux (OR = 1.051, P = 0.029, and optimal cutoff = 45) were independent predictors of standard antireflux therapy efficacy. The combination predictive value did not show better results than either individual predictor.

CONCLUSIONS

Proximal MNBI < 2140 Ω may be used to screen patients with nonacid GERC suitable for standard antireflux therapy and in standardized management algorithms for nonacid GERC. In the absence of MNBI, weakly acid reflux > 45 can be used as an auxiliary indicator.

Oral and Inhaled Fosamprenavir Reverses Pepsin-Induced Damage in a Laryngopharyngeal Reflux Mouse Model

OBJECTIVE

More than 20% of the US population suffers from laryngopharyngeal reflux. Although dietary/lifestyle modifications and alginates provide benefit to some, there is no gold standard medical therapy. Increasing evidence suggests that pepsin is partly, if not wholly, responsible for damage and inflammation caused by laryngopharyngeal reflux. A treatment specifically targeting pepsin would be amenable to local, inhaled delivery, and could prove effective for endoscopic signs and symptoms associated with nonacid reflux. The aim herein was to identify small molecule inhibitors of pepsin and test their efficacy to prevent pepsin-mediated laryngeal damage in vivo.

METHODS

Drug and pepsin binding and inhibition were screened by high-throughput assays and crystallography. A mouse model of laryngopharyngeal reflux (mechanical laryngeal injury once weekly for 2 weeks and pH 7 solvent/pepsin instillation 3 days/week for 4 weeks) was provided inhibitor by gavage or aerosol (fosamprenavir or darunavir; 5 days/week for 4 weeks; n = 3). Larynges were collected for histopathologic analysis.

RESULTS

HIV protease inhibitors amprenavir, ritonavir, saquinavir, and darunavir bound and inhibited pepsin with IC50 in the low micromolar range. Gavage and aerosol fosamprenavir prevented pepsin-mediated laryngeal damage (i.e., reactive epithelia, increased intraepithelial inflammatory cells, and cell apoptosis). Darunavir gavage elicited mild reactivity and no discernable protection; aerosol protected against apoptosis.

CONCLUSIONS

Fosamprenavir and darunavir, FDA-approved therapies for HIV/AIDS, bind and inhibit pepsin, abrogating pepsin-mediated laryngeal damage in a laryngopharyngeal reflux mouse model. These drugs target a foreign virus, making them ideal to repurpose. Reformulation for local inhaled delivery could further improve outcomes and limit side effects.

LEVEL OF EVIDENCE

NA. Laryngoscope, 133:S1-S11, 2023.

Alginates for Protection Against Pepsin-Acid Induced Aerodigestive Epithelial Barrier Disruption

OBJECTIVE

Gastroesophageal reflux disease (GERD) and laryngopharyngeal reflux (LPR) are chronic conditions caused by backflow of gastric and duodenal contents into the esophagus and proximal aerodigestive tract, respectively. Mucosal barrier dysfunction resultant from the synergistic actions of chemical injury and the mucosal inflammatory response during reflux contributes to symptom perception. Alginates effectively treat symptoms of mild to moderate GERD and have recently shown benefit for LPR. In addition to forming a "raft" over gastric contents to reduce acidic reflux episodes, alginates have been found to bind the esophageal mucosa thereby preserving functional barrier integrity measured by transepithelial electrical resistance. The aim of this study was to further examine the topical protective capacity of alginate-based Gaviscon Advance (GA) and Double Action (GDA) against pepsin-acid mediated aerodigestive epithelial barrier dysfunction in vitro.

STUDY DESIGN

Translational.

METHODS

Immortalized human esophageal and vocal cord epithelial cells cultured in transwells were pretreated with liquid formula GA, GDA, matched viscous placebo solution, or saline (control), then treated for 1 h with saline, acid (pH 3-6) or pepsin (0.1-1 mg/ml) at pH 3-6. Endpoint measure was taken of horseradish peroxidase (HRP) allowed to diffuse across monolayers for 2 h.

RESULTS

Pepsin (0.1-1 mg/ml) at pH 3-6 increased HRP flux through cultures pretreated with saline or placebo (p < 0.05); acid alone did not. GA and GDA prevented barrier dysfunction.

CONCLUSIONS

GA and GDA preserved epithelial barrier function during pepsin-acid insult better than placebo suggesting that protection was due to alginate. These data support topical protection as a therapeutic approach to GERD and LPR. Laryngoscope, 132:2327-2334, 2022.

Diagnostics of Gastrointestinal Motility and Function: Update for Clinicians

Disorders of gastrointestinal (GI) tract motility and function are prevalent in the general population and negatively affect quality of life [...].

Kyoto international consensus report on anatomy, pathophysiology and clinical significance of the gastro-oesophageal junction

OBJECTIVE

An international meeting was organised to develop consensus on (1) the landmarks to define the gastro-oesophageal junction (GOJ), (2) the occurrence and pathophysiological significance of the cardiac gland, (3) the definition of the gastro-oesophageal junctional zone (GOJZ) and (4) the causes of inflammation, metaplasia and neoplasia occurring in the GOJZ.

DESIGN

Clinical questions relevant to the afore-mentioned major issues were drafted for which expert panels formulated relevant statements and textural explanations.A Delphi method using an anonymous system was employed to develop the consensus, the level of which was predefined as ≥80% of agreement. Two rounds of voting and amendments were completed before the meeting at which clinical questions and consensus were finalised.

RESULTS

Twenty eight clinical questions and statements were finalised after extensive amendments. Critical consensus was achieved: (1) definition for the GOJ, (2) definition of the GOJZ spanning 1 cm proximal and distal to the GOJ as defined by the end of palisade vessels was accepted based on the anatomical distribution of cardiac type gland, (3) chemical and bacterial (Helicobacter pylori) factors as the primary causes of inflammation, metaplasia and neoplasia occurring in the GOJZ, (4) a new definition of Barrett's oesophagus (BO).

CONCLUSIONS

This international consensus on the new definitions of BO, GOJ and the GOJZ will be instrumental in future studies aiming to resolve many issues on this important anatomic area and hopefully will lead to better classification and management of the diseases surrounding the GOJ.

Current advances in the diagnosis and management of gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) is very common and defined as troublesome symptoms owing to excessive acid reflux. The spectrum of GERD is broad, including not only erosive esophagitis and Barrett's esophagus but also nonerosive reflux disease (NERD), reflux hypersensitivity, and functional heartburn. Patients with reflux symptoms despite normal endoscopy remain common clinical presentation, can be heterogeneous overlapping with functional gastrointestinal disorders. Ambulatory esophageal pH monitoring with and without impedance helps the diagnosis of NERD. Metrics such as baseline impedance and postreflux swallow induced peristaltic wave enhance diagnostic accuracy in patients with inconclusive diagnoses. The major treatment of all manifestations of GERD is acid suppression with proton pump inhibitors, while other therapies, such as reflux-reducing agents and adjunctive medications, can be individualized where the response to traditional management is incomplete. GERD patients often need long-term treatment due to frequent relapses. Anti-reflux surgery can be effective too. Endoscopic therapies have some promising results, but long-term outcomes remain to be determined.

Complex Gastroesophageal Reflux Disease

Gastroesophageal reflux disease (GERD) is the most prevalent gastrointestinal disorder posing diagnostic and therapeutic challenges. Diagnosis should be objectively defined with endoscopy and pH testing, while novel metrics may augment diagnosis for inconclusive GERD cases, including the postreflux swallow-induced peristaltic wave index and esophageal mucosal impedance. Conditions that overlap with or mimic GERD should be considered such as achalasia, rumination, and eosinophilic esophagitis. Genetic testing for proton pump inhibitor metabolism is an option for precision therapy in complex persistent GERD. Proton pump inhibitor refractory GERD may require medical, surgical, or endoscopic therapies. The presence of GERD should be objectively evaluated in achalasia patients treated with peroral endoscopic myotomy, and further studies are needed to determine timing of this evaluation. Patients with scleroderma are at a high risk for GERD owing to abnormal esophageal motility and should be managed with aggressive medical therapy and lifestyle changes given the high prevalence of esophagitis and Barrett's esophagus in this population. Further studies are needed to understand the complex mechanisms of GERD in idiopathic pulmonary fibrosis and lung transplantation.

Devices for esophageal function testing

Background and Aims

Esophageal function testing is an integral component of the evaluation of refractory GERD and esophageal motility disorders. This review summarizes the current technologies available for esophageal function testing, including the functional luminal imaging probe (FLIP), high-resolution esophageal manometry (HRM), and multichannel intraluminal impedance (MII) and pH monitoring.

Methods

We performed a MEDLINE, PubMed, and MAUDE database literature search to identify pertinent clinical studies through March 2021 using the following key words: esophageal manometry, HRM, esophageal impedance, FLIP, MII, and esophageal pH testing. Technical data were gathered from traditional and web-based publications, proprietary publications, and informal communications with pertinent vendors. The report was drafted, reviewed, and edited by the American Society for Gastrointestinal Endoscopy Technology Committee and approved by the Governing Board of the American Society for Gastrointestinal Endoscopy.

Results

FLIP is a high-resolution impedance planimetry system used for pressure and dimension measurement in the esophagus, pylorus, and anal sphincter. FLIP provides complementary information to HRM for esophageal motility disorders, especially achalasia. The Chicago classification, based on HRM data, is a widely adopted algorithmic scheme used to diagnose esophageal motility disorders. MII detects intraluminal bolus movement and, combined with pH measurement or manometry, provides information on acid and non-acid gastroesophageal reflux and bolus transit in patients with refractory GERD and for preoperative evaluation for anti-reflux procedures.

Conclusions

Esophageal function testing techniques (FLIP, HRM, and MII-pH) have diagnostic and prognostic value in the evaluation of esophageal motility disorders and refractory GERD. Newer technologies and classification systems have enabled an increased understanding of these diseases.

Expanded Indication for Magnetic Sphincter Augmentation: Outcomes in Weakly Acidic Reflux Compared to Standard GERD Patients

BACKGROUND

Magnetic sphincter augmentation (MSA) is a modern surgical anti-reflux technique with proven efficacy and low postoperative morbidity in patients with acidic reflux. The aim of this retrospective review study was to evaluate the symptomatic outcome of MSA in patients with weakly acidic reflux.

METHODS

From a prospectively collected clinical database, comprising all 327 patients that underwent MSA at our institution, a total of 67 patients with preoperative weakly acidic reflux measured in the 24-h impedance-pH-metry were identified. Postoperative gastrointestinal symptoms, proton pump inhibitor intake (PPI), GERD Health-Related Quality-of-Life (GERD-HRQL), alimentary satisfaction (AS), and patients' overall satisfaction were evaluated within highly standardized follow-up appointments. Furthermore, outcome of these patients was compared to the postoperative outcome of a comparable group of patients with a preoperative acidic reflux.

RESULTS

At a median follow-up of 24 months, none of the patients with weakly acidic reflux presented with persistent dysphagia, or underwent endoscopic dilatation or reoperation. The postoperative GERD-HRQL score was significantly reduced (2 vs. 20; p = 0.001) and the median AS was 9/10. Preoperative daily heartburn, regurgitations, and respiratory complaints were improved in 95%, 95%, and 96% of patients, respectively. A total of 10% of the patients continued to use PPIs postoperatively. No significant difference was observed in terms of postoperative outcome or quality of life when comparing weakly acidic reflux patients with those diagnosed with preoperative acidic reflux.

CONCLUSION

Magnetic sphincter augmentation significantly improves GERD-related symptoms and quality of life in patients with weakly acidic reflux with very low postoperative morbidity.

An update on current treatment strategies for laryngopharyngeal reflux symptoms

Laryngopharyngeal reflux (LPR) is a syndrome caused by reflux of gastric contents into the pharynx or larynx, which leads to symptoms of throat clearing, hoarseness, pain, globus sensation, cough, excess mucus production in the throat, and dysphonia. LPR is a challenging condition, as there is currently no gold standard for diagnosis or treatment, and thus this presents a burden to the healthcare system. Strategies for treatment of LPR are numerous. Medical therapies include proton pump inhibitors, which are first line, H2 receptor antagonists, alginates, and baclofen. Other noninvasive treatment options include lifestyle therapy and the external upper esophageal sphincter compression device. Endoscopic and surgical options include antireflux surgery, magnetic sphincter augmentation, and transoral incisionless fundoplication. Functional laryngeal disorders and laryngeal hypersensitivity can present as LPR symptoms with or without gastroesophageal reflux disease. Though there are minimal studies in this area, neuromodulators and behavioral interventions are potential treatment options. Given the complexity of these patients and numerous available treatment options, we propose a treatment algorithm to help clinicians diagnose and triage patients into an appropriate therapy.

Degree of concordance on the management of patients with gastroesophageal reflux disease. A study among specialists that are members of the Sociedad Latinoamericana de Neurogastroenterología (SLNG)

INTRODUCTION AND AIMS

Due to its different clinical manifestations, gastroesophageal reflux disease (GERD) requires diverse diagnostic and therapeutic interventions. The aim of the study was to evaluate the degree of agreement among Latin American specialists, with respect to the management of GERD.

MATERIALS AND METHODS

A cross-sectional study was conducted through a survey with 42 statements (22 related to diagnosis and 20 to treatment) applied to 56 specialists from Latin America. There were 4 possible statement responses: in complete agreement, in partial agreement, in partial disagreement, and in complete disagreement. Reproducibility, level of agreement, and concordance were measured through the Kappa statistic.

RESULTS

The response rate was 81% (47/56). General concordance was low, given that there was complete concordance in only 12 statements (28.6%). There was partial concordance in 22 statements (52.4%) and no concordance in 8 (19%). The following themes had the most disagreement: the performance of endoscopy before beginning treatment, the use of proton pump inhibitors (PPIs) in patients with extraesophageal symptoms and with no typical symptoms, and the combined use of PPIs and prokinetics.

CONCLUSIONS

In the present study, we found that there was agreement among the Latin American specialists for the diagnosis and management of GERD in less than one-third of the recommendations considered standard. The low concordance could be related to the fact that the availability of diagnostic tools and medications, as well as the prevalence of GERD phenotypes, are different in each country.

2020 Seoul Consensus on the Diagnosis and Management of Gastroesophageal Reflux Disease

Gastroesophageal reflux disease (GERD) is a condition in which gastric contents regurgitate into the esophagus or beyond, resulting in either troublesome symptoms or complications. GERD is heterogeneous in terms of varied manifestations, test findings, and treatment responsiveness. GERD diagnosis can be established with symptomatology, pathology, or physiology. Recently the Lyon consensus defined the "proven GERD" with concrete evidence for reflux, including advanced grade erosive esophagitis (Los Angeles classification grades C and or D esophagitis), long-segment Barrett's mucosa or peptic strictures on endoscopy or distal esophageal acid exposure time > 6% on 24-hour ambulatory pH-impedance monitoring. However, some Asian researchers have different opinions on whether the same standards should be applied to the Asian population. The prevalence of GERD is increasing in Asia. The present evidence-based guidelines were developed using a systematic review and meta-analysis approach. In GERD with typical symptoms, a proton pump inhibitor test can be recommended as a sensitive, cost-effective, and practical test for GERD diagnosis. Based on a meta-analysis of 19 estimated acid-exposure time values in Asians, the reference range upper limit for esophageal acid exposure time was 3.2% (95% confidence interval, 2.7-3.9%) in the Asian countries. Esophageal manometry and novel impedance measurements, including mucosal impedance and a post-reflux swallow-induced peristaltic wave, are promising in discrimination of GERD among different reflux phenotypes, thus increasing its diagnostic yield. We also propose a long-term strategy of evidence-based GERD treatment with proton pump inhibitors and other drugs.

Clinical Characteristics of Esophageal Motility Disorders in Patients With Heartburn

BACKGROUND/AIMS

Esophageal motility disorders (EMDs) contribute to the pathophysiology of gastroesophageal reflux disease. However, the causes of EMDs and their impact on gastroesophageal reflux disease-associated symptoms remain unknown. This study aims to elucidate clinical features associated with various types of EMDs in patients with heartburn symptoms.

METHODS

Of the 511 patients who underwent high-resolution manometry, 394 who were evaluated for heartburn symptoms were examined. Patients subjected to high-resolution manometry were classified into 4 groups: outflow obstruction group, hypermotility group, hypomotility group, and normal motility group. Symptoms were evaluated using 3 questionnaires. Patient characteristics and symptoms for each EMD type were compared with those of the normal motility group.

RESULTS

Of the 394 patients, 193 (48.9%) were diagnosed with EMDs, including 71 with outflow obstruction, 15 with hypermotility, and 107 with hypomotility. The mean dysphagia score was significantly higher in each of the 3 EMD groups compared with those with normal motility. The mean acid reflux and dyspepsia scores were significantly lower in the outflow obstruction group (P < 0.05). The mean body mass index and median Brinkman index were significantly higher in the hypermotility group (P = 0.001 and P = 0.018, respectively), whereas the mean diarrhea and constipation scores were significantly lower in the hypomotility group (P < 0.05).

CONCLUSIONS

The results of our study indicate that different EMDs have distinct characteristics. Cigarette smoking and high body mass index were associated with esophageal hypermotility. Assessment of the dysphagia symptom scores may help identify patients with EMDs.

Laryngopharyngeal reflux: is laparoscopic fundoplication an effective treatment?

INTRODUCTION

Laryngopharyngeal reflux (LPR) is difficult to diagnose and treat owing to uncertainty relating to the underlying pathology. The initial management of LPR includes lifestyle modifications and oral medications. In patients who have failed to respond to proton pump inhibitor (PPI) therapy, anti-reflux surgery is considered; laparoscopic fundoplication is the surgery of choice. The primary aim of this review is to identify whether fundoplication is effective in improving signs and symptoms of LPR. The secondary aim is to identify whether patients who have had a poor response to PPIs are likely to have symptom improvement with surgery. The objective of the study is to establish the effect of laparoscopic fundoplication on the reflux symptom index score (RSI).

METHODS

PubMed, Embase, Medline and Cochrane databases were used to search according to the PRISMA guidelines. Original articles assessing the efficacy of fundoplication in relieving symptoms of LPR were included. For each study, the efficacy endpoints and safety outcomes were recorded.

FINDINGS

Nine studies from 844 initial records met the inclusion criteria: one prospective case control study, one retrospective case-control study, four prospective case series and three retrospective case series involving 287 fundoplications. All nine studies found fundoplication to be effective in improving symptoms of LPR (p < 0.05).

CONCLUSION

Current evidence suggests laparoscopic fundoplication is an effective treatment for LPR and should be considered if medical management is unsuccessful.

Degree of concordance on the management of patients with gastroesophageal reflux disease. A study among specialists that are members of the Sociedad Latinoamericana de Neurogastroenterología (SLNG)

INTRODUCTION AND AIMS

Due to its different clinical manifestations, gastroesophageal reflux disease (GERD) requires diverse diagnostic and therapeutic interventions. The aim of the study was to evaluate the degree of concordance among Latin American specialists, with respect to the management of GERD.

MATERIALS AND METHODS

A cross-sectional study was conducted through a survey with 42 statements (22 related to diagnosis and 20 to treatment) applied to 56 specialists from Latin America. There were 4 possible statement responses: in complete agreement, in partial agreement, in partial disagreement, and in complete disagreement. Reproducibility, level of agreement, and concordance were measured through the Kappa statistic.

RESULTS

The response rate was 81% (47/56). General concordance was low, given that there was complete concordance in only 12 statements (28.6%). There was partial concordance in 22 statements (52.4%) and no concordance in 8 (19%). The following themes had the most disagreement: the performance of endoscopy before beginning treatment, the use of proton pump inhibitors (PPIs) in patients with extraesophageal symptoms and with no typical symptoms, and the combined use of PPIs and prokinetics.

CONCLUSIONS

In the present study, we found that there was agreement among the Latin American specialists for the diagnosis and management of GERD in less than one-third of the recommendations considered standard. The low concordance could be related to the fact that the availability of diagnostic tools and medications, as well as the prevalence of GERD phenotypes, are different in each country.

Laparoscopic Toupet Fundoplication for the Treatment of Laryngopharyngeal Reflux: Results at Medium-Term follow-Up

BACKGROUND

The effect of laparoscopic Toupet fundoplication (LTF) for the treatment of laryngopharyngeal reflux (LPR) is unclear. The purpose of this study is to investigate the feasibility and effectiveness of LTF for the treatment of LPR-related symptoms and disease-specific quality of life (QoL) up to 3-year follow-up.

MATERIALS AND METHODS

Observational cohort study (2015-2019). Patients suffering from LPR were included. Preoperative evaluation included esophagogastroduodenoscopy, esophageal manometry and 24-h pH/impedance study. Symptoms and QoL were measured with the reflux symptom index (RSI) and the laryngopharyngeal reflux-health-related quality of life (LPR-HRQL) validate questionnaires at baseline and during follow-up.

RESULTS

Eighty-six patients were included. Twenty-three (27%) patients had pure LPR while 63 (73%) presented with combined LPR/GERD. Cough (89.7%), dyspnea/choking (39.6%) and asthma (25.6%) were the most commonly reported extraesophageal symptoms. The median (interquartile range, IQR) total RSI score before operation and at 3-month, 6-month, 1-year, 2-year and 3-year follow-up was 36.1 (10.3), 9.58 (12.3), 11.8 (10.2), 12.4 (9.6), 12.0 (13.1) and 10.1 (12.0), respectively. The median (IQR) total LPR-HRQL score before operation and at 3-month, 6-month, 1-year, 2-year and 3-year follow-up was 57.4 (22.2), 13.4 (14.9), 15.2 (12.8), 11.4 (10.9) and 11.9 (13.5), respectively. The subscores "voice," "cough," "throat" and "swallow" showed a significant improvement after intervention. Compared to baseline, each per-year follow-up pairwise comparison was significantly improved (p < 0.001).

CONCLUSIONS

LTF seems feasible, effective and promising for the treatment of LPR with improved symptoms and disease-specific patients' quality of life perception up to 3-year follow-up.

Sex-Based Differences in pH Parameters and Esophageal Impedance of Patients With Gastroesophageal Reflux Disease

Background/Aims: The incidence of reflux esophagitis (RE) has a striking predominance in males. Conversely, non-erosive reflux disease (NERD) is more common in females. This imbalance of gastroesophageal reflux disease (GERD) implies sex-related differences in its pathogenesis. However, limited studies have analyzed the sex-based differences in pH parameters and esophageal impedance of GERD patients.

Methods: This study evaluated sex-based pathogenesis differences by comparing reflux episodes, mean nocturnal baseline impedance (MNBI) values, and post-reflux swallow-induced peristaltic wave (PSPW) index values of males with GERD and females with GERD using 24-h multichannel intraluminal impedance and pH monitoring.

Results: We analyzed 181 patients (102 males and 79 females) with GERD. Reflux symptom index (RSI) scores were higher in females than that in males (P < 0.05). Males had significantly longer acid exposure times, higher DeMeester scores, and more acid reflux episodes than females (P < 0.05). Females had more instances of weakly acidic reflux than males (P < 0.01). The PSPW index values of males and females were similar (P > 0.05). Compared with females, males had lower MNBI values for the mid and distal esophagus (P < 0.05). However, with increasing age, the MNBI values of females decreased more rapidly than those of males. MNBI values of elderly patients of both sexes older than 60 years were similar.

Conclusions: Acid reflux is more likely to occur in males; however, females tend to have more instances of weakly acid reflux. The integrity of the esophageal mucosa is more fragile in males than in females; however, the esophageal mucosal barrier attenuates more rapidly with increasing age in females than in males.

Heartburn sensation in nonerosive reflux disease: pattern of superficial sensory nerves expressing TRPV1 and epithelial cells expressing ASIC3 receptors

The underlying causes of heartburn, characteristic symptom of gastroesophageal reflux disease (GERD), remain incompletely understood. Superficial afferent innervation of the esophageal mucosa in nonerosive reflux disease (NERD) may drive nociceptive reflux perception, but its acid-sensing role has not yet been established. Transient receptor potential vanilloid subfamily member-1 (TRPV1), transient receptor potential melastatin 8 (TRPM8), and acid-sensing ion channel 3 (ASIC3) are regulators of sensory nerve activity and could be important reflux-sensing receptors within the esophageal mucosa. We characterized TRPV1, TRPM8, and ASIC3 expression in esophageal mucosa of patients with GERD. We studied 10 patients with NERD, 10 with erosive reflux disease (ERD), 7 with functional heartburn (FH), and 8 with Barrett's esophagus (BE). Biopsies obtained from the distal esophageal mucosa were costained with TRPV1, TRPM8, or ASIC3, and CGRP, CD45, or E-cadherin. RNA expression of TRPV1, TRPM8, and ASIC3 was assessed using qPCR. Patients with NERD had significantly increased expression of TRPV1 on superficial sensory nerves compared with ERD (P = 0.028) or BE (P = 0.017). Deep intrapapillary nerve endings did not express TRPV1 in all phenotypes studied. ASIC3 was exclusively expressed on epithelial cells most significantly in patients with NERD and ERD (P ≤0.0001). TRPM8 was expressed on submucosal CD45+ leukocytes. Superficial localization of TRPV1-immunoreactive nerves in NERD, and increased ASIC3 coexpression on epithelial cells in NERD and ERD, suggests a mechanism for heartburn sensation. Esophageal epithelial cells may play a sensory role in acid reflux perception and act interdependently with TRPV1-expressing mucosal nerves to augment hypersensitivity in patients with NERD, raising the enticing possibility of topical antagonists for these ion channels as a therapeutic option.NEW & NOTEWORTHY We demonstrate for the first time that increased pain perception in patients with nonerosive reflux disease likely results from expression of acid-sensitive channels on superficial mucosal afferents and esophageal epithelial cells, raising the potential for topical therapy.

Pepsin Promotes Activation of Epidermal Growth Factor Receptor and Downstream Oncogenic Pathways, at Slightly Acidic and Neutral pH, in Exposed Hypopharyngeal Cells

Pepsin refluxate is considered a risk factor for laryngopharyngeal carcinogenesis. Non-acidic pepsin was previously linked to an inflammatory and tumorigenic effect on laryngopharyngeal cells in vitro. Yet there is no clear evidence of the pepsin-effect on a specific oncogenic pathway and the importance of pH in this process. We hypothesized that less acidic pepsin triggers the activation of a specific oncogenic factor and related-signalling pathway. To explore the pepsin-effect in vitro, we performed intermittent exposure of 15 min, once per day, for a 5-day period, of human hypopharyngeal primary cells (HCs) to pepsin (1 mg/mL), at a weakly acidic pH of 5.0, a slightly acidic pH of 6.0, and a neutral pH of 7.0. We have documented that the extracellular environment at pH 6.0, and particularly pH 7.0, vs. pH 5.0, promotes the pepsin-effect on HCs, causing increased internalized pepsin and cell viability, a pronounced activation of EGFR accompanied by NF-κB and STAT3 activation, and a significant upregulation of EGFR, AKT1, mTOR, IL1β, TNF-α, RELA(p65), BCL-2, IL6 and STAT3. We herein provide new evidence of the pepsin-effect on oncogenic EGFR activation and its related-signaling pathway at neutral and slightly acidic pH in HCs, opening a window to further explore the prevention and therapeutic approach of laryngopharyngeal reflux disease.

Erosive Esophagitis and Symptoms of Gastroesophageal Reflux Disease in Patients with Morbid Obesity with and without Type 2 Diabetes: a Cross-sectional Study

BACKGROUND

Type 2 diabetes (T2DM) is associated with gastroesophageal reflux disease (GERD) in the general population, but the relationship between these conditions in candidates for bariatric surgery is uncertain. We compared the prevalence of GERD and the association between GERD symptoms and esophagitis among bariatric candidates with and without T2DM.

METHODS

Cross-sectional study of baseline data from the Oseberg study in Norway. Both groups underwent gastroduodenoscopy and completed validated questionnaires: Gastrointestinal Symptom Rating Scale and Gastroesophageal Reflux Disease Questionnaire. Participants with T2DM underwent 24-h pH-metry.

RESULTS

A total of 124 patients with T2DM, 81 women, mean (SD) age 48.6 (9.4) years and BMI 42.3 (5.5) kg/m², and 64 patients without T2DM, 46 women, age 43.0 (11.0) years and BMI 43.0 (5.0) kg/m², were included. The proportions of patients reporting GERD-symptoms were low (< 29%) and did not differ significantly between groups, while the proportions of patients with esophagitis were high both in the T2DM and non-T2DM group, 58% versus 47%, p = 0.16. The majority of patients with esophagitis did not have GERD-symptoms (68-80%). Further, 55% of the patients with T2DM had pathologic acid reflux. Among these, 71% also had erosive esophagitis, whereof 67% were asymptomatic.

CONCLUSIONS

The prevalence of GERD was similar in bariatric patients with or without T2DM, and the proportion of patients with asymptomatic GERD was high independent of the presence or absence of T2DM. Accordingly, GERD may be underdiagnosed in patients not undergoing a preoperative endoscopy or acid reflux assessment.

TRIAL REGISTRATION

Clinical Trials.gov number NCT01778738.