Characteristics of reflux episodes and symptom association in patients with erosive esophagitis and nonerosive reflux disease: study using combined impedance-pH off therapy

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%.

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.

Risk factors and 26-years worldwide prevalence of endoscopic erosive esophagitis from 1997 to 2022: a meta-analysis

Erosive esophagitis (EE) is the part of gastroesophageal reflux disease (GERD) spectrum and may progress to esophageal adenocarcinoma. Due to its progressivity and unclear prevalence, we aim to identify the factors contributing in EE to decide the need for further examination. We performed a PRISMA 2020-based systematic search through PubMed and other resources up to June 2, 2022. Study quality was assessed using the Newcastle-Ottawa Scale (NOS). The odds ratio (OR) of each factor and worldwide prevalence of EE were measured. There are 114 observational studies included with a total of 759,100 participants. Out of 29 factors, the significant risk factors are age ≥ 60 y.o. (OR 2.03 [1.81-2.28]), White/Caucasian (OR 1.67 [1.40-1.99]), unmarried (OR 1.08 [1.03-1.14]), having GERD ≥ 5 years (OR 1.27 [1.14-1.42]), general obesity (OR 1.78 [1.61-1.98]), central obesity (OR 1.29 [1.18-1.42]), diabetes mellitus (DM) (OR 1.24 [1.17-1.32]), hypertension (OR 1.16 [1.09-1.23]), dyslipidemia (OR 1.15 [1.06-1.24]), hypertriglyceridemia (OR 1.42 [1.29-1.57]), hiatal hernia (HH) (OR 4.07 [3.21-5.17]), and non-alcoholic fatty liver disease (NAFLD) (OR 1.26 [1.18-1.34]). However, H. pylori infection (OR 0.56 [0.48-0.66]) and atrophic gastritis (OR 0.51 [0.31-0.86]) are protective towards EE. This study demonstrates that age, ethnicity, unmarried, long-term GERD, metabolic diseases, HH, and NAFLD act as risk factors for EE, whereas H. pylori infection and atrophic gastritis act as protective factors. These findings may enable a better understanding of EE and increase greater awareness to address its growing burden.

Effect of Body Weight and Obesity on Esophageal Function

The incidence of obesity in the population is gradually increasing. Obesity can cause a variety of complications in the digestive system such as gastroesophageal reflux disease, and impacts the integrity of the esophageal mucosal barrier and esophageal motility. However, not many studies have focused on the effect of varying degrees of obesity on the esophagus. A total of 611 participants were included in this study. We divided them into three groups according to their body mass index (BMI): the normal weight group, the overweight group, and the obesity group. We performed a retrospective comparison between groups based on indicators from high resolution esophageal manometry (HREM) and 24-hour pH impedance monitoring, and did a correlation analysis on multiple indicators such as esophageal mucosal barrier, esophageal motility, and acid reflux. The mean nocturnal baseline impedance (MNBI) in the overweight and obesity groups was lower than that in the normal group. The MNBI of the subjects in Z5-Z6 channels in the overweight group was significantly lower than that in the normal group. With respect to Z3-Z6 channels, MNBI values in the obesity group were significantly lower than those in the normal group. 'The acid exposure time (AET), the DeMeester scores (DMS) and 24-hour total reflux episodes was significantly higher in the obesity group than those in the normal and overweight groups. The upper esophageal sphincter (UES) residual pressure, and intrabolus pressure (IBP) in the overweight and obesity groups were significantly higher than those in the normal group. In addition, lower esophageal sphincter (LES) resting pressure, and esophagogastric junction contractile integral (EGJ-CI) in the obesity group were significantly higher than those in the normal group. We found that increase in body weight affected the integrity of esophageal mucosa, and different degrees of increase associated with different degrees and different aspects of changes in esophageal motility.

Proximal reflux frequency not correlated with atypical gastroesophageal reflux disease (GERD) symptoms

Though most known for heartburn and regurgitation, gastroesophageal reflux disease (GERD) is attributed to countless atypical, extra-esophageal (EE) manifestations like cough and throat clearing. While GERD has been studied extensively, the relationship between reflux character and symptom manifestation remains poorly understood. The aim of this study was to examine proximal reflux frequency and its relationship with typical or atypical symptoms. 540 (75.1% female, 24.9% male) pH-impedance monitoring studies from the last 3-years were divided by symptom indication and retrospectively reviewed for proximal reflux frequency, total acid exposure time, mean nocturnal baseline impedance, and total reflux episodes in both abnormal and normal, and borderline studies. Baseline characteristics were also collected. Both total reflux events and mean proximal reflux frequency were found to differ significantly between those with typical versus atypical symptoms. Total reflux events [median (IQR)] were 43.5 (24.0-74.0) in typical patients and 35.0 (20.0-57.0) in atypical patients (P-value 0.0369). Proximal reflux frequency [median (IQR)] was 12.0 (4.0-19.0) typical and 7.0 (3.0-17.0) atypical (P-value 0.0348). Results for exclusively abnormal studies also favored typical patients but not significantly. Baseline characteristics and use of gastric acid control did not differ significantly. Proximal reflux frequency was observed to increase among those with typical GERD symptoms. Total acid reflux events were also significantly higher on average with typical patients. Our findings that proximal reflux frequency is reduced in patients with atypical symptoms compared with patients with typical symptoms suggest that proximal reflux exposure may play a significant role in the symptom presentation of typical classic heartburn and regurgitation symptoms. The differential diagnosis for atypical EE symptoms is vast and can be multifactorial. Our results indicate proximal reflux events may contribute to atypical EE symptoms less than previously reported.

Ambulatory pH-Impedance Findings Confirm That Grade B Esophagitis Provides Objective Diagnosis of Gastroesophageal Reflux Disease

INTRODUCTION

The Lyon Consensus designates Los Angeles (LA) grade C/D esophagitis or acid exposure time (AET) >6% on impedance-pH monitoring (MII-pH) as conclusive for gastroesophageal reflux disease (GERD). We aimed to evaluate proportions with objective GERD among symptomatic patients with LA grade A, B, and C esophagitis on endoscopy.

METHODS

Demographics, clinical data, endoscopy findings, and objective proton-pump inhibitor response were collected from symptomatic prospectively enrolled patients from 2 referral centers. Off-therapy MII-pH parameters included AET, number of reflux episodes, mean nocturnal baseline impedance, and postreflux swallow-induced peristaltic wave index. Objective GERD evidence was compared between LA grades.

RESULTS

Of 155 patients (LA grade A: 74 patients, B: 61 patients, and C: 20 patients), demographics and presentation were similar across LA grades. AET >6% was seen in 1.4%, 52.5%, and 75%, respectively, in LA grades A, B, and C. Using additional MII-pH metrics, an additional 16.2% with LA grade A and 47.5% with LA grade B esophagitis had AET 4%-6% with low mean nocturnal baseline impedance and postreflux swallow-induced peristaltic wave index; there were no additional gains using the number of reflux episodes or symptom-reflux association metrics. Compared with LA grade C (100% conclusive GERD based on endoscopic findings), 100% of LA grade B esophagitis also had objective GERD but only 17.6% with LA grade A esophagitis ( P < 0.001 compared with each). Proton-pump inhibitor response was comparable between LA grades B and C (74% and 70%, respectively) but low in LA grade A (39%, P < 0.001).

DISCUSSION

Grade B esophagitis indicates an objective diagnosis of GERD.

Traditional Chinese medicine based on Tongjiang methodology combined with proton pump inhibitor (PPI) step-down in treating non-erosive reflux disease: a study protocol for a multicentered, randomized controlled clinical trial

BACKGROUND

Non-erosive reflux disease (NERD) is characterized by typical gastroesophageal reflux symptoms, such as heartburn and regurgitation but an absence of esophageal mucosal damage during upper gastrointestinal endoscopy. Although proton pump inhibitors (PPIs) are the first line therapy, almost 50% of patients with NERD fail to respond to this treatment. Traditional Chinese medicine (TCM) can better relieve the symptoms of NERD. Therefore, a randomized controlled trial (RCT) was designed to investigate the efficiency of TCM granules based on Tongjiang (TJ) methodology combined with PPI step-down therapy for NERD patients who did not respond to PPIs alone.

METHOD

This multicentered, double-blinded, RCT with two parallel groups will recruit 174 participants who will be randomized into the TCM granules combined with PPI step-down group (n = 87) and the TCM granules placebo combined with PPI step-down group (n = 87). Both groups of participants will receive 6 weeks of treatment and 4 weeks of follow-up, and all participants will be assessed for related symptoms, mental health status, and quality of life at each visit. The primary outcome measurements include visual analog scale (VAS) for heartburn and regurgitation and the major symptoms scale. The secondary outcome measurements include PPI withdrawal rate, symptom recurrence rate, minor symptoms scale, SF-36, PRO, SAS, SDS, GERD-HRQL, and TCM syndromes scales.

DISCUSSION

Previous research has shown that TCM is capable to alleviate NERD symptoms. This trial will help to provide a better understanding of the synergistic efficiency of the combination of TCM and PPIs, to explore whether the dosage of PPIs can be reduced after the supplement of TCM granules and to provide a feasible plan to reduce dependencies or withdraw NERD patients from PPIs. The outcome of this trial is expected to reduce the symptom recurrence rates, lessen patients' physical and psychological burdens, and achieve good social benefits.

TRIAL REGISTRATION

Clinicaltrials.gov NCT04340297. Registered on April 9, 2020.

Analysis of local expression of inflammatory cytokines genes in patients with gastroesophageal reflux disease and its association with types and number of gastroesophageal refluxes

The aim of the study was to evaluate gene expression of proinflammatory cytokines in esophageal mucosa in patients with erosive esophagitis (EE) and non-erosive form (NERD) of gastroesophageal reflux disease (GERD) and perform correlation analysis between the genes expression and types and number of gastroesophageal refluxes. Methods. This was a single-center prospective study. Esophageal mucosa samples were taken from lower part of the esophagus during endoscopy. Expression of IL-1b, IL-10, IL-18, TNFA, TLR4, GATA3, CD68 and beta-2 macroglobulin genes was assessed with ImmunoQuantex assays. Multichannel intraluminal esophageal pH-impedance studies were performed with Ohmega recorder and 2pH-6impedance catheters. Results. Data of 60 patients (females - 34; mean age (M±SD) 54.6 years, 20 - with erosive esophagitis) were available for the analysis. In those with EE, there was higher expression of IL-18 (5.89±0.4 vs 5.28±1.1, p=0.04), GATA3 (2.92±0.86 vs 2.23±0.96, p=0.03) genes, and inflammatory index (92.12±32.41% vs 70.1±30.8%, p=0.02) compared to NERD. Direct correlation was found between acid exposure time and expression of IL-1b (Spearman rank R = 0.29), IL-18 (R=0.31), TNFA (R=0.35), GATA3 (R=0.34), TLR4 (R=0.29), CD68 (R=0.37) genes and inflammatory index (R=0.3). Indirect correlation was revealed between mean рН and expressions of IL-18 (R= -0.28), TNFA (R= -0.33), GATA3 (R= -0.28), TLR4 (R= -0.28), CD68 (R= -0.39) genes and inflammatory index (R= -0.17). No correlation was found between the genes’ expression and number of gastroesophageal refluxes. Conclusions: Expression of proinflammatory cytokines’ genes differ in patients with EE and NERD. There is a correlation between expression of studied genes and esophageal acidity.

Local inflammatory response to gastroesophageal reflux: Association of gene expression of inflammatory cytokines with esophageal multichannel intraluminal impedance-pH data

BACKGROUND

Gene expression of inflammatory cytokines may take part in the pathophysiology of different forms of gastroesophageal reflux disease (GERD).

AIM

To explore gene expression of inflammatory cytokines in esophageal mucosa in patients with erosive esophagitis (EE) and non-erosive forms of GERD (NERD) and its association with data of esophageal multichannel intraluminal impedance-pH (MII-pH) measurements.

METHODS

This was a single-center prospective study. Esophageal mucosa samples were taken from the lower part of the esophagus during endoscopy. Expression of interleukin (IL)-1β, IL-10, IL-18, tumor necrosis factor α (TNFA), toll-like receptor 4 (TLR4), GATA binding protein 3 (GATA3), differentiation cluster 68 (CD68) and β-2 microglobulin genes in esophageal mucosa was assessed with ImmunoQuantex assays. MII-pH measurements were performed on all the participants. Diagnosis of GERD was confirmed by the results of the MII-pH data. Based on the endoscopy, patients were allocated to the groups of EE and NERD. The control group consisted of non-symptomatic subjects with normal endoscopy and MII-pH results. We used nonparametric statistics to compare the differences between the groups. Association of expression of the mentioned genes with the results of the MII-pH data was assessed with Spearman’s rank method.

RESULTS

Data from 60 patients with GERD and 10 subjects of the control group were available for the analysis. Higher expression of IL-18 (5.89 ± 0.4 vs 5.28 ± 1.1, P = 0.04) and GATA3 (2.92 ± 0.86 vs 2.23 ± 0.96, P = 0.03) was found in the EE group compared to NERD. Expression of IL-1β, IL-18, TNFA, and TLR4 was lower (P < 0.05) in the control group compared to EE and NERD. Esophageal acid exposure correlated with the expression of IL-1β (Spearman’s rank r = 0.29), IL-18 (r = 0.31), TNFA (r = 0.35), GATA3 (r = 0.34), TLR4 (r = 0.29), and CD68 (r = 0.37). Mean esophageal рН correlated inversely with the expression of IL-18, TNFA, GATA3, TLR4, and CD68. No association of gene expression with the number of gastroesophageal refluxes was found.

CONCLUSION

In patients with EE, local expression of IL-18 and GATA3 was higher compared to subjects with NERD. Esophageal acid exposure correlated directly with expression of IL-1β, IL-18, TNFA, TLR4, CD68, and β-2 microglobulin genes. Inverse correlation was revealed between expression of IL-18, TNFA, GATA3, TLR4, and CD68 and mean esophageal pH.

Mean nocturnal baseline impedance, a novel metric of multichannel intraluminal impedance-pH monitoring in diagnosing gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) is a common disease with increasing prevalence worldwide. However, the diagnosis of GERD is challenging because there are no definite gold standard criteria. Recently, a novel impedance parameter, namely mean nocturnal baseline impedance (MNBI), has been proposed, which reflects the burden of longitudinal reflux and the integrity of esophageal mucosa. MNBI has shown an immense promise for increasing the diagnostic rate of multichannel intraluminal impedance-pH (MII-pH) monitoring and predicting the response to proton pump inhibitor (PPI) or anti-reflux intervention in patients with reflux symptoms. The present paper reviews the association between baseline impedance and esophageal mucosal integrity, the acquisition of MNBI in 24-h MII-pH monitoring, the clinical utilization of MNBI in improving the diagnosis rate of GERD in patients with typical reflux symptoms, predicting the response to PPI or anti-reflux treatment in these patients, the utilization of MNBI in diagnosing patients with atypical symptoms or extra-esophageal symptoms, and the correlation between reflux burden and MNBI. MNBI should be routinely assessed using MII-pH monitoring.

Phenotypes of gastroesophageal reflux disease: classification, pathogenesis and diagnostic criteria: A review

The literature review focuses on the current understanding of visceral hypersensitivity mechanisms in the esophagus. Mechanisms of peripheral and central sensitization and their relation to heartburn symptoms are covered in detail. Diagnostic criteria and algorithms for non-erosive reflux disease, functional heartburn, and esophagus hypersensitivity based on pH-impedance testing and high-resolution esophageal manometry data are presented.

Applying Lyon Consensus criteria in the work-up of patients with proton pump inhibitory-refractory heartburn

BACKGROUND

A hierarchical approach for gastro-oesophageal reflux disease (GERD) diagnosis by impedance-pH monitoring was proposed by the Lyon Consensus, based on acid exposure time (AET) and supportive impedance metrics.

AIMS

To establish the clinical value of Lyon Consensus criteria in the work-up of patients with proton pump inhibitory (PPI)-refractory heartburn.

METHODS

Expert review of off-therapy impedance-pH tracings from unproven GERD patients with PPI-refractory heartburn prospectively evaluated at referral centers. Impedance metrics, namely total reflux episodes, postreflux swallow-induced peristaltic wave index, and mean nocturnal baseline impedance, were assessed. Expert review of on-therapy preoperative impedance-pH tracings from a separate cohort of surgically treated erosive/nonerosive GERD cases.

RESULTS

Off-therapy, normal, inconclusive, and abnormal AET was found in 59%, 17%, and 23% of 317 cases. Supportive evidence of GERD was provided by abnormal impedance metrics in up to 22% and 62% of cases in the normal and inconclusive AET groups, respectively. Adding the cases with inconclusive AET and abnormal impedance metrics to the abnormal AET group, a significant increase in GERD evidence was observed (from 23% to 37% of cases, p < 0.0002). At the on-therapy presurgical evaluation, abnormal/inconclusive AET and supraphysiological values of impedance metrics showed ongoing reflux in 21% and 90% of 96 cases, respectively (p < 0.00001); a relationship between on-therapy ongoing reflux and PPI-refractory heartburn was confirmed by the favorable surgical outcome at 3-year follow-up, 88% of cases being in persistent off-PPI heartburn remission.

CONCLUSIONS

Impedance-pH monitoring, off- and on-therapy, is of high clinical value in the work-up of patients with PPI-refractory heartburn.

Application of Lyon Consensus criteria for GORD diagnosis: evaluation of conventional and new impedance-pH parameters

OBJECTIVE

To validate Lyon Consensus criteria for diagnosing gastro-oesophageal reflux disease (GORD) by reflux monitoring.

DESIGN

Manual review of impedance-pH tracings from patients with proton pump inhibitor (PPI)-dependent heartburn, evaluated off PPI. Acid exposure time (AET) thresholds defined by the Lyon Consensus and impedance parameters were investigated, namely, total refluxes (TRs), postreflux swallow-induced peristaltic wave (PSPW) index and mean nocturnal baseline impedance (MNBI).

RESULTS

The study included 488 patients, 178 (36%) with normal (<4%) AET, 89 (18%) with inconclusive (4%-6%) AET and 221 (45%) with abnormal (>6%) AET, alongside with 70 healthy controls. At receiver operating characteristic analysis, area under curve was 0.89, 0.95 and 0.89 for TRs, PSPW index and MNBI, respectively, and threshold values were 40, 50% and 2000 Ω; the 4% physiological AET threshold defined by the Lyon Consensus showed 100% specificity but 63% sensitivity. The thresholds defined for impedance parameters were validated against AET by means of ordered logistic regression, being in concordance with the 4% AET threshold (OR 2.5 for TRs, 18.9 for PSPW index and 5.7 for MNBI). TRs positivity and concordant PSPW index/MNBI positivity were found in 80%-90% of patients in the abnormal AET group, in 73%-74% of cases in the inconclusive AET group and in 28%-40% of cases in the group with normal AET.

CONCLUSIONS

Our results show the overall validity of the Lyon Consensus approach to GORD diagnosis. Adding evaluation of impedance parameters, namely, TRs, PSPW index and MNBI to AET appraisal, substantially improves the diagnostic yield of reflux monitoring.

The Discrepancy Between Subjective and Objective Clinical Endpoints in Gastroesophageal Reflux Disease

Therapeutic outcome in gastroesophageal reflux disease (GERD) is commonly determined by both subjective and objective clinical endpoints. Clinicians frequently use symptom improvement as a key benchmark of clinical success, in conjunction with normalization of objective parameters such as esophageal acid exposure and inflammation. However, GERD therapeutic trials have demonstrated that a substantial number of patients rendered asymptomatic, whether through medical, surgical, or endoscopic intervention, continue to have persistent abnormal esophageal acid exposure and erosive esophagitis. The opposite has also been demonstrated in therapeutic trials, where patients remained symptomatic despite normalization of esophageal acid exposure and complete resolution of esophageal inflammation. Moreover, there is no substantive evidence that symptomatic response to antireflux treatment requires complete esophageal mucosal healing or normalization of esophageal acid exposure. Thus, it appears that a certain level of improvement in objective parameters is needed to translate into meaningful changes in symptoms and health-related quality of life of GERD patients. This supports the need to reconsider the commonly used "hard" clinical endpoints to evaluate therapeutic trials in GERD.

Quantitative assessment of multichannel intraluminal impedance pH and its clinical implications

We sought to quantify the characteristics of acid reflux episodes in patients with extraesophageal GERD symptoms (EES), hiatal hernia (HH), and erosive esophagitis (EroE) using multichannel intraluminal impedance pH (MII‐pH) and investigate the correlation between impedance parameters and high resolution esophageal manometry (HREM). This was a retrospective analysis of esophageal manometric and impedance data inpatients with typical GERD symptoms who underwent both HREM and 24 h MII‐pH tests. Within the three patient subgroups, we evaluated impedance metrics such as average height of reflux, total duration of reflux, maximum duration of reflux, average pH, and average area of reflux. We also introduce a novel composite reflux index (CRI) metric, which is a measure of reflux height, duration, and acidity. Patients with EES exhibited a 29.3% increase in average height of reflux, compared to non‐EES patients (p < 0.01); the average height of reflux was found to be an independent predictor of EES (p < 0.01). Patients with HH showed a 190% longer total reflux duration (p < 0.01, vs. non‐HH patients). Total reflux duration was twice as long in EroE patients compared to those without (p = 0.02). Average CRI was significantly different within all three subgroup comparisons (p < 0.01). Impedance metrics shared weak negative correlations with lower esophageal sphincter (LES) rest pressure and distal contractile integral (DCI), and weak positive correlations with % absent peristalsis (p < 0.05 to p < 0.01 for various parameters). Quantitative impedance metrics provide useful insight into the pathophysiology of reflux in patients with EES, HH, and EroE.

Reflux characteristics triggering post-reflux swallow-induced peristaltic wave (PSPW) in patients with GERD symptoms

BACKGROUND

Esophageal chemical clearance has been evaluated with the post-reflux swallow-induced peristaltic wave (PSPW) index. The factors triggering PSPW in Gastro-esophageal reflux disease (GERD) have not yet been investigated. This multicenter study was aimed at evaluating the characteristics of reflux episodes associated with PSPW occurrence in patients with typical GERD symptoms.

METHODS

Impedance-pH tracings from patients with typical reflux symptoms were analyzed. Sixteen healthy subjects were included for comparison. Multivariate analysis was performed to determine predictors of PSPW events.

KEY RESULTS

Impedance-pH tracings from 60 patients and 16 healthy subjects were evaluated. A total of 3454 refluxes were recorded. In patients, comparing reflux episodes followed with those not followed by a PSPW, significantly higher proportions of acid (79% vs. 74%, p: 0.02), mixed (47% vs. 32%, p: 0.0001) and proximal refluxes (34% vs. 20%, p: 0.0001) were observed. A multivariate analysis, acid (OR: 1.3, 95% CI: 1.05-1.6), mixed (OR: 2, 95% CI: 1.6-2.3), and proximal (OR: 2.1, 95% CI: 1.7-2.5) refluxes were independently associated with PSPWs. Reflux episodes followed by a PSPW were characterized by a significantly higher bolus clearing time [(mean ± SD) 41 s ± 6 s vs. 30 s ± 5 s, p < 0.05] whereas nadir pH value of reflux events preceding PSPWs was tangentially but not significantly lower [(mean ± SD) 2.61 ± 1.22 vs. 2.74 ± 1.26, p: 0.057].

CONCLUSIONS AND INFERENCES

Acid, mixed and proximal refluxes, and their duration are key factors in eliciting PSPWs. PSPW represents a response to reflux directly related to the potential harmfulness of reflux contents.

Pathophysiology of Pediatric Gastroesophageal Reflux Disease: Similarities and Differences With Adults

Gastroesophageal reflux (GOR) is defined as "the passage of gastric contents into the esophagus with or without regurgitation and vomiting" and gastroesophageal reflux disease (GORD) is defined "when GOR leads to troublesome symptoms affecting the daily functioning and/or complications." This definition was first developed in 2006 by the Montreal consensus group (1) and later on adopted by pediatric gastroenterology societies such as ESPGHAN and NASPGHAN in 2009 (2). The definition of gastroesophageal reflux reveals little about its pathophysiology and is focused on symptomatology. In this way, it acts as an umbrella term for the multifactorial causes of the disease and the various phenotypes encountered; from functional heartburn to hypersensitive esophagus and nonerosive reflux disease, to erosive esophagitis and Barrett's esophagus. This article is devoted to the pathophysiology of pediatric GORD in comparison to adult GORD and is divided in 2 parts. In the first part, we will systematically describe the different mechanisms for the generation and clearance of reflux events, while on the second part we will discuss the mechanisms involved in symptoms generation. Finally, we will discuss the similarities and differences between pediatric and adult GORD.

Post-per-oral endoscopic myotomy heartburn: It's not always reflux: Expert review

Patients with achalasia frequently develop gastroesophageal reflux (GER)-related symptoms and complications after per-oral endoscopic myotomy (POEM). Reflux symptoms are thought to be due to GER and the current treatment of post-POEM GER focuses on acid suppression with proton pump inhibitors (PPI). However, reflux symptoms in achalasia patients post-POEM can be due to true reflux, nonreflux esophageal acidification due to stasis or acid fermentation, or esophageal hypersensitivity to chemical or mechanical stimuli. True acidic reflux is not always the cause of reflux symptoms. Twenty-four-hour pH monitoring with impedance is essential to differentiate causes of esophageal acidification. PPI is useful only in true acidic reflux. Detection of acid fermentation requires manual review of a 24-h pH study, as automated review often overestimates acid exposure time due to its inability to differentiate true reflux from fermentation. Stasis of ingested acidic food warrants evaluation of esophageal emptying by timed barium esophagogram. In cases of inadequate emptying, esophagogastric junction (EGJ) distensibility can be evaluated by a functional lumen imaging probe. Impaired distensibility with inadequate esophageal emptying suggests treatment failure and may require retreatment. In treatment-refractory patients, esophageal hypersensitivity should be considered and treated with neuromodulators. Thus, the diagnostic approach to post-POEM reflux symptoms should evolve to identify various patterns of esophageal acidification, esophageal emptying patterns, EGJ distensibility, and hypersensitivity. Consequently, the treatment of GER post-POEM should not be limited to treating esophageal acidification by reflux, but should encompass other causes of acidification and esophageal hypersensitivity.

Refractory Gastroesophageal Reflux Disease: A Management Update

Gastroesophageal reflux disease (GERD) is one of the most frequent gastrointestinal disorders. Proton pump inhibitors (PPIs) are effective in healing lesions and improving symptoms in most cases, although up to 40% of GERD patients do not respond adequately to PPI therapy. Refractory GERD (rGERD) is one of the most challenging problems, given its impact on the quality of life and consumption of health care resources. The definition of rGERD is a controversial topic as it has not been unequivocally established. Indeed, some patients unresponsive to PPIs who experience symptoms potentially related to GERD may not have GERD; in this case the definition could be replaced with “reflux-like PPI-refractory symptoms.” Patients with persistent reflux-like symptoms should undergo a diagnostic workup aimed at finding objective evidence of GERD through endoscopic and pH-impedance investigations. The management strategies regarding rGERD, apart from a careful check of patient's compliance with PPIs, a possible change in the timing of their administration and the choice of a PPI with a different metabolic pathway, include other pharmacologic treatments. These include histamine-2 receptor antagonists (H2RAs), alginates, antacids and mucosal protective agents, potassium competitive acid blockers (PCABs), prokinetics, gamma aminobutyric acid-B (GABA-B) receptor agonists and metabotropic glutamate receptor-5 (mGluR5) antagonists, and pain modulators. If there is no benefit from medical therapy, but there is objective evidence of GERD, invasive antireflux options should be evaluated after having carefully explained the risks and benefits to the patient. The most widely performed invasive antireflux option remains laparoscopic antireflux surgery (LARS), even if other, less invasive, interventions have been suggested in the last few decades, including endoscopic transoral incisionless fundoplication (TIF), magnetic sphincter augmentation (LINX) or radiofrequency therapy (Stretta). Due to the different mechanisms underlying rGERD, the most effective strategy can vary, and it should be tailored to each patient. The aim of this paper is to review the different management options available to successfully deal with rGERD.

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.

Diagnostic yield and reliability of post-prandial high-resolution manometry and impedance-ph for detecting rumination and supragastric belching in PPI non-responders

BACKGROUND

Supragastric belching (SGB) and rumination are behavioral disorders associated with proton pump inhibitor (PPI) non-response and can be diagnosed using multichannel intraluminal impedance-pH (MII-pH) and post-prandial high-resolution impedance manometry (PPHRIM). This pilot study compared diagnostic yield and inter-rater agreement for SGB and rumination using MII-pH and PPHRIM.

METHODS

Three esophageal physiologists performed blinded interpretations of MII-pH and PPHRIM in 22 PPI non-responders. Raters selected from 4 diagnostic impressions (normal, GERD, behavioral disorders, GERD+behavioral disorders) without clinical context. Primary outcomes were diagnostic impressions compared against clinical gold standard impression, between raters, and between test modalities. Following a 28-month wash-out period, raters re-interpreted MII-pH with clinical context and under consensus definition of diagnostic criteria.

KEY RESULTS

Compared to gold standard, rater accuracy for presence of behavioral disorders ranged from 45 to 77% on MII-pH and 45-59% on PPHRIM. On MII-pH, inter-rater agreement was fair for diagnosis (ĸ0.32, p < 0.01) and suboptimal for presence of behavioral disorders (ĸ0.13, p = 0.14). On PPHRIM, inter-rater agreement was suboptimal for both diagnosis (ĸ0.03, p = 0.34) and presence of a behavioral disorder (ĸ-0.22, p = 0.96). Inter-rater agreement improved in post hoc MII-pH interpretations. Rumination was more frequently identified on PPHRIM (23, 35%) compared to MII-pH (7, 11%).

CONCLUSIONS AND INFERENCES

Diagnostic accuracy and inter-rater agreement are higher for MII-pH than PPHRIM, and behavioral disorders are more frequently identified on PPHRIM. Identifying behavioral disorders on MII-pH and PPHRIM has implications for clinical evaluation of PPI non-response; clinical context is essential for accurate study interpretation. Further work is needed to standardize definitions and interpretations.

Multichannel impedance monitoring for distinguishing nonerosive reflux esophagitis with minor changes on endoscopy in children

Objectives:

There are reports describing the relationship between baseline impedance level and esophageal mucosal integrity at endoscopy, such as erosive and nonerosive reflux esophagitis. However, many children with symptoms of gastroesophageal reflux disease have normal findings or minor changes on esophagogastroduodenoscopy. We aimed to examine whether modest changes at esophagogastroduodenoscopy can be evaluated and correlated with esophageal multichannel intraluminal impedance monitoring.

Methods:

Patients (ages 0–17 years) with upper gastrointestinal symptoms who underwent combined esophagogastroduodenoscopy and multichannel intraluminal impedance monitoring at the Women’s and Children’s Hospital, Adelaide, Australia, between 2014 and 2016 were retrospectively studied and the following data were collected and used for analysis: demographics, multichannel intraluminal impedance data, included baseline impedance. Endoscopic findings were classified by modified Los Angeles grading, Los Angeles N as normal, Los Angeles M as with minimal change such as the erythema, pale mucosa, or friability of the mucosa following biopsy. Patients on proton pump inhibitor were excluded.

Results:

Seventy patients (43 boys; 61%) were enrolled with a mean age of 7.9 years (range 10 months to 17 years). Fifty-one patients (72.9%) were allocated to Los Angeles N, while Los Angeles M was evident in 19 patients (27.1%). Statistically significant differences were observed in the following parameters: frequency of acid and nonacid reflux and baseline impedance in channels 5 and 6. The median values of the data were 18.3 episodes, 16.0 episodes, 2461.0 Ω, 2446.0 Ω in Los Angeles N, 36.0 episodes, 31.0 episodes, 2033.0 Ω, 2009.0 Ω in Los Angeles M, respectively.

Conclusion:

Lower baseline impedance is helpful in predicting minimal endoscopic changes in the lower esophagus. A higher frequency of acid and nonacid reflux episodes was also predictive of minimal endoscopic change in the lower esophagus.

Esophageal pH increments associated with post-reflux swallow-induced peristaltic waves show the occurrence and relevance of esophago-salivary reflex in clinical setting

BACKGROUND

Following acid perfusion, esophageal pH is restored by swallowed bicarbonate-containing saliva secreted in response to a vagal esophago-salivary reflex. At impedance-pH monitoring, the post-reflux swallow-induced peristaltic wave (PSPW) index puts into relationship timely post-reflux swallows with the number of reflux events: Low values typify reflux-related heartburn (RRH) and lack of on-therapy improvement characterizes proton pump inhibitor (PPI) failure. Considerable esophageal pH increments associated with PSPWs could demonstrate the occurrence of esophago-salivary reflex in clinical setting, while its relevance could be shown by lower esophageal pH increments in PPI-refractory RRH.

METHODS

Prospective multicenter study in patients with PPI-refractory or PPI-responsive RRH evaluated with off-PPI impedance-pH monitoring. Increments in pH associated with PSPWs were measured and the mean calculated to obtain the PSPW-associated ∆pH.

KEY RESULTS

The mean PSPW-associated ∆pH in 294 RRH patients was 1.2 ± 0.7 and was lower in 137 PPI-refractory (1.0 ± 0.6) than in 157 PPI-responsive (1.5 ± 0.6) cases (p < 0.0001). Lower PSPW-associated ∆pH was independently related to PPI failure at multivariable logistic regression analysis (OR 0.16, 95% CI 0.09-0.26). At ROC analysis, comparing PPI-refractory to PPI-responsive cases the AUC for PSPW-associated ∆pH was 0.76 (95% CI 0.71-0.82), the best cutoff value being 1.2.

CONCLUSIONS AND INFERENCES

Considerable PSPW-associated pH increments demonstrate the occurrence of esophago-salivary reflex in clinical setting. Lower increments in PPI-refractory RRH cases show the clinical relevance of esophago-salivary reflex, confirming that PSPW represents a defense mechanism against reflux. PSPW-associated ∆pH can efficiently predict PPI response in patients undergoing off-therapy impedance-pH monitoring.

Value of adjunctive evidence from MII-pH monitoring and high-resolution manometry in inconclusive GERD patients with AET 4-6

OBJECTIVES

Gastro-esophageal reflux disease (GERD) is a common disease in gastroenterology outpatients. However, some patients with typical reflux symptoms does not satisfy diagnostic criteria. This study was to explore the value of adjunctive evidence from multichannel intraluminal impedance-pH (MII-pH) monitoring and esophageal high-resolution manometry (HRM) in inconclusive GERD patients with acid exposure time (AET) 4-6%.

METHODS

Endoscopy, MII-pH monitoring and esophageal HRM were retrospectively analyzed from consecutive patients with typical reflux symptoms in a tertiary hospital from 2013 to 2019. Patients were categorized as conclusive or inconclusive GERD according to AET. Adjunctive evidence for GERD diagnosis from Lyon Consensus were collected and analyzed.

RESULTS

Among 147 patients with typical reflux symptoms, conclusive GERD was found in only 31.97% of patients (N = 47). The remaining 100 patients (68.03%) were inconclusive GERD, of whom 28% (N = 28) had AET 4-6%. These patients suffered similar reflux burden and impaired esophageal movement. Inconclusive GERD patients with AET 4-6% had lots of positive adjunctive evidence from HRM and MII-pH monitoring. In receiver operating characteristic analysis, mean nocturnal baseline impedance (MNBI) and post-reflux swallow-induced peristaltic wave index (PSPWI) had an area under the curve (AUC) of 0.839 (CI: 0.765-0.913, p < 0.001) and 0.897 (CI: 0.841-0.953, p < 0.001), respectively, better than total reflux episode (AUC of 0.55, p = 0.33). When MNBI was combined with PSPWI, the AUC was elevated to 0.910 (CI: 0.857-0.963, p < 0.001).

CONCLUSIONS

Inconclusive GERD patients with AET 4-6% have similar acid burden and esophagus motility dysfunction to GERD patients. MNBI and PSPWI are pivotal adjunctive evidence for diagnosing GERD when AET is borderline.

Patients With Definite and Inconclusive Evidence of Reflux According to Lyon Consensus Display Similar Motility and Esophagogastric Junction Characteristics

Background/Aims

The role of esophageal high-resolution manometry (HRM) within Lyon consensus phenotypes, especially patients with inconclusive gastroesophageal reflux disease (GERD) evidence, has not been fully investigated. In this multicenter, observational study we aim to compare HRM parameters in patients with GERD stratified according to the Lyon consensus.

Methods

Clinical and endoscopic data, HRM and multichannel intraluminal impedance-pH (MII-pH) studies performed off proton pump inhibitor therapy in patients with esophageal GERD symptoms were reviewed. Lyon consensus criteria identified pathological GERD, reflux hypersensitivity, functional heartburn, and inconclusive GERD. Patients, with inconclusive GERD were further subdivided into 2 groups based on total reflux numbers (≤ 80 or > 80 reflux episodes) during the MII-pH recording time.

Results

A total of 264 patients formed the study cohort. Pathological GERD and inconclusive GERD patients were associated with higher numbers of reflux episodes, lower mean nocturnal baseline impedance (MNBI) values, and a higher proportion of patients with pathologic MNBI compared to functional heartburn (P < 0.05 for each comparison). On multivariate analysis, pathological GERD and inconclusive GERD patients, both with ≤ 80 or > 80 reflux episodes, were significantly associated with pathologic esophagogastric junction contractile integral values and with presence of hiatus hernia (type 2/3 esophagogastric junction). Patients with inconclusive GERD and > 80 reflux episodes were significantly associated with fragmented peristalsis and ineffective esophageal motility whilst inconclusive GERD with ≤ 80 reflux episodes were significantly associated with fragmented peristalsis.

Conclusion

Esophageal motor parameters on HRM are similar between pathologic and inconclusive GERD according to the Lyon consensus.

Longitudinal and Circumferential Distributions of Dysplasia and Early Neoplasia in Barrett's Esophagus: A Pooled Analysis of Three Prospective Studies

INTRODUCTION

Studies have shown that dysplasia in Barrett's esophagus (BE) has a predilection for the right hemisphere. There is limited information on the longitudinal distribution. The aim was to determine both the longitudinal and circumferential distributions of dysplasia and early neoplasia from 3 prospective studies.

METHODS

This is a pooled analysis from 3 prospective studies of patients with treatment-naive BE. Both circumferential and longitudinal locations (for BE segments greater than 1 cm) of dysplastic and early neoplastic lesions were recorded.

RESULTS

A total of 177 dysplastic and early neoplastic lesions from 91 patients were included in the pooled analysis; of which 59.3% (n = 105) were seen on high-definition white light endoscopy, 29.4% (n = 52) on advanced imaging, and 11.2% (n = 20) with random biopsies. The average Prague score was C3M5. Of 157 lesions within BE segments greater than 1 cm, 49 (34.8%) lesions were in the proximal half, whereas 92 lesions (65.2%) were in the distal half (P < 0.001). The right hemisphere of the esophagus contained 55% (86/157) of the total lesions compared with 45% (71/157) for the left hemisphere (P = 0.02). This was because of the presence of high-grade dysplasia being concentrated in the right hemisphere compared with the left hemisphere (60% vs 40%, P = 0.002).

DISCUSSION

In this pooled analysis of prospective studies, both low-grade dysplasia and high-grade dysplasia are more frequently found in the distal half of the Barrett's segment. This study confirms that the right hemisphere is a hot spot for high-grade dysplasia. Careful attention to these locations is important during surveillance endoscopy.

Extra-esophageal symptoms in individuals with and without erosive esophagitis: a case-control study in Albania

INTRODUCTION

Erosive reflux esophagitis caused a large clinical spectrum of symptoms. Our aim was to assess the prevalence of extra-esophageal symptoms in individuals with and those without erosive esophagitis in Albania.

METHODS

A case-control study was conducted at the Regional Hospital of Durres, the second main district in Albania, a transitional country in South Eastern Europe, including 248 patients with erosive esophagitis (aged 46.5 ± 16.3 years) and 273 controls (aged 46.4 ± 16.0 years; response rate: 70%) enrolled during the period January 2013-June 2014. Both cases and controls underwent upper endoscopy. Information on socio-demographic characteristics and lifestyle factors was also collected. Binary logistic regression was used to assess the association of erosive esophagitis and extra-esophageal symptoms.

RESULTS

Patients with erosive esophagitis had a higher prevalence of excessive alcohol consumption, smoking, sedentarity, non-Mediterranean diet and obesity compared to their control counterparts (9% vs. 5%, 70% vs. 49%, 31% vs. 17%, 61% vs. 49% and 22% vs. 9%, respectively). Upon adjustment for all socio-demographic characteristics and lifestyle/behavioral factors, there was evidence of a strong association of erosive esophagitis with chronic cough (OR = 3.2, 95% CI = 1.7-5.8), and even more so with laryngeal disorders (OR = 4.4, 95% CI = 2.6-7.5). In all models, the association of erosive esophagitis with any extra-esophageal symptoms was strong and mainly consistent with each of the symptoms separately (fully-adjusted model: OR = 4.6, 95% CI = 2.9-7.3).

CONCLUSION

Our findings indicate that the prevalence of extra-esophageal symptoms is higher among patients with erosive esophagitis in a transitional country characterized conventionally by employment of a Mediterranean diet.

Reflux symptoms and oesophageal acidification in treated achalasia patients are often not reflux related

OBJECTIVE

After treatment, achalasia patients often develop reflux symptoms. Aim of this case-control study was to investigate mechanisms underlying reflux symptoms in treated achalasia patients by analysing oesophageal function, acidification patterns and symptom perception.

DESIGN

Forty treated achalasia patients (mean age 52.9 years; 27 (68%) men) were included, 20 patients with reflux symptoms (RS+; Gastro-Oesophageal Reflux Disease Questionnaire (GORDQ) ≥8) and 20 without reflux symptoms (RS-: GORDQ <8). Patients underwent measurements of oesophagogastric junction distensibility, high-resolution manometry, timed barium oesophagogram, 24 hours pH-impedance monitoring off acid-suppression and oesophageal perception for acid perfusion and distension. Presence of oesophagitis was assessed endoscopically.

RESULTS

Total acid exposure time during 24 hours pH-impedance was not significantly different between patients with (RS+) and without (RS-) reflux symptoms. In RS+ patients, acid fermentation was higher than in RS- patients (RS+: mean 6.6% (95% CI 2.96% to 10.2%) vs RS-: 1.8% (95% CI -0.45% to 4.1%, p=0.03) as well as acid reflux with delayed clearance (RS+: 6% (95% CI 0.94% to 11%) vs RS-: 3.4% (95% CI -0.34% to 7.18%), p=0.051). Reflux symptoms were not related to acid in both groups, reflected by a low Symptom Index. RS+ patients were highly hypersensitive to acid, with a much shorter time to heartburn perception (RS+: 4 (2-6) vs RS-:30 (14-30) min, p<0.001) and a much higher symptom intensity (RS+: 7 (4.8-9) vs RS-: 0.5 (0-4.5) Visual Analogue Scale, p<0.001) during acid perfusion. They also had a lower threshold for mechanical stimulation.

CONCLUSION

Reflux symptoms in treated achalasia are rarely caused by gastro-oesophageal reflux and most instances of oesophageal acidification are not reflux related. Instead, achalasia patients with post-treatment reflux symptoms demonstrate oesophageal hypersensitivity to chemical and mechanical stimuli, which may determine symptom generation.

The Natural Course of Gastroesophageal Reflux Disease: A Critical Appraisal of the Literature

Interpreting natural course studies have been very difficult due to their retrospective design, lack of standardization, reliability of reported mucosal findings, liberal use of antireflux medications and accuracy of chart documentation. Studies provided a wide range of progression rates of patients from nonerosive reflux disease (NERD) to erosive esophagitis (EE). However, direct progression from NERD to Barrett's esophagus appears to be an uncommon phenomenon. Importantly, progression of NERD patients was commonly reported to low grades of EE, which are currently considered inconclusive of gastroesophageal reflux disease. Reports of progression rates from low grades to high grades EE also vary considerably. Progression of patients with EE, without metaplastic epithelium underneath the inflammation, to Barrett's esophagus is relatively uncommon. Recently, it was also recognized that regression from high grades to low grades EE and from EE to NERD is a common phenomenon affecting up to 25% of the patients from each group.

The Role of Symptom Association Analysis in Gastroesophageal Reflux Testing

Gastroesophageal reflux disease is characterized by the reflux of gastric contents into the esophagus with an estimated worldwide prevalence of 8%-33%. The current paradigm in gastroesophageal reflux disease diagnosis relies on recognition of symptoms and/or the presence of mucosal disease at the time of esophagogastroduodenoscopy. Recognition of symptoms, however, can arise with challenges, particularly when patients complain of less typical symptoms. Since first reported in 1969 by Spencer et al., the application of prolonged intraesophageal pH monitoring to identify pathologic reflux has evolved considerably. Utility of pH monitoring aims to investigate the degree of acid burden and frequency of reflux episode, and the relationship between symptoms and acid reflux events. This relationship is represented by either the Symptom Index, Symptom Sensitivity Index, Symptom Association Probability, or Ghillebert Probability Estimate. This article reviews symptom-association analysis during esophageal reflux testing, covering the literature on current methods of reflux testing, interpretation of symptom association, and practical issues that can arise during symptom analysis.

Esophageal reflux hypersensitivity: Non-GERD or still GERD?

The most recent iteration of the classifications for functional esophageal disorders, Rome IV, proposed relevant modifications of the previous definitions for Rome III. They specifically considered increased esophageal acid exposure as the marker of gastroesophageal reflux disease (GERD), including the remaining part of non-erosive reflux disease patients with normal acid in the group with functional alterations, considering both reflux hypersensitivity and functional heartburn. However, recent pathophysiological and therapeutic data suggest the need for a return to including reflux hypersensitivity in the GERD spectrum. Indeed, physiologic alterations in esophageal mucosal integrity and chemical clearance, the presence of microscopic esophagitis, and strict symptom-reflux association support the concept that reflux hypersensitivity pertains to GERD. Surgical anti-reflux therapy has resulted in positive outcomes, even in the long term, in patients with reflux hypersensitivity and not in those with functional heartburn. Moreover, clinical trials using neuromodulators have been scarce and provided conflicting results. As a result, the real progress of the Rome IV classifications is in dispute. This article aims to summarize the most recent knowledge of non-erosive reflux disease and reflux hypersensitivity to discuss the utility of Rome IV criteria in the identification and management of functional esophageal disorders.

Normal values and regional differences in oesophageal impedance-pH metrics: a consensus analysis of impedance-pH studies from around the world

OBJECTIVE

Limitations of existing impedance-pH thresholds include small sample size of normative studies, inclusion of artefactual pH drops and incorrect identification of impedance reflux events. We aimed to obtain new impedance-pH thresholds from expert consensus analysis of tracings from a large number of healthy subjects.

DESIGN

Of 541 studies performed worldwide using two different systems (Diversatek, USA, and Laborie, Netherlands), 150 tracings with oesophageal diagnoses, behavioural disorders and study-related artefacts were excluded. The remainder studies were subject to two reviewer consensus analysis, in-person or through video conference, consisting of editing meals and pH drops, identification of impedance reflux and postreflux swallow-induced peristaltic wave (PSPW) using strict pre-established criteria and measurement of distal mean nocturnal baseline impedance (MNBI).

RESULTS

Consensus analysis was performed in 391 tracings (age 32.7 years, range 18-71, 54.2% female). Normative thresholds were significantly different between Diversatek and Laborie (total acid exposure time: 2.8% and 5%; reflux episodes: 55 and 78; MNBI at 3 cm: 1400 and 1500 ohms, at 5 cm: 1400 and 1800 ohms). Males had higher acid exposure, more reflux episodes and lower MNBI. Significant regional differences were identified, including higher PSPW scores in Western countries, and higher MNBI in Asia using Diversatek, and higher acid exposure in the Netherlands, higher MNBI in Asia and South Africa, and lower MNBI in Turkey using Laborie.

CONCLUSION

Normal impedance-pH monitoring thresholds have regional and system-related differences. Clinical interpretation needs to use normal thresholds valid for the system used and world region, following careful editing of the tracings.

A SIGE-SINGEM-AIGO technical review on the clinical use of esophageal reflux monitoring

Patients with esophageal symptoms potentially associated with gastroesophageal reflux disease such as heartburn, regurgitation, chest pain, or cough represent one of the most frequent reasons for referral to gastroenterological evaluation. The utility of esophageal reflux monitoring in clinical practice is: (1) to accurately define reflux burden, (2) to segregate patients according to reflux monitoring results as true GERD, reflux hypersensitivity and functional heartburn, and (3) to establish a treatment plan. With this in mind, in the last decade, investigations and technical advances, with the introduction of impedance-pH monitoring and wireless pH capsule, have enhanced our understanding and management of GERD. The following recommendations were discussed and approved after a comprehensive review of the medical literature pertaining to reflux testing techniques and their recent application. This review created under the auspices of the Società Italiana di Gastroenterologia ed Endoscopia Digestiva (SIGE), Società Italiana di Neuro-Gastro-Enterologia e Motilità (SINGEM) and Associazione Italiana Gastroenterologi ed Endoscopisti Digestivi Ospedalieri (AIGO) is intended to help clinicians in applying reflux studies in the most fruitful manner within the context of their patients with esophageal symptoms.

ACG Clinical Guidelines: Clinical Use of Esophageal Physiologic Testing

Esophageal symptoms are common and may indicate the presence of gastroesophageal reflux disease (GERD), structural processes, motor dysfunction, behavioral conditions, or functional disorders. Esophageal physiologic tests are often performed when initial endoscopic evaluation is unrevealing, especially when symptoms persist despite empiric management. Commonly used esophageal physiologic tests include esophageal manometry, ambulatory reflux monitoring, and barium esophagram. Functional lumen imaging probe (FLIP) has recently been approved for the evaluation of esophageal pressure and dimensions using volumetric distension of a catheter-mounted balloon and as an adjunctive test for the evaluation of symptoms suggestive of motor dysfunction. Targeted utilization of esophageal physiologic tests can lead to definitive diagnosis of esophageal disorders but can also help rule out organic disorders while making a diagnosis of functional esophageal disorders. Esophageal physiologic tests can evaluate obstructive symptoms (dysphagia and regurgitation), typical and atypical GERD symptoms, and behavioral symptoms (belching and rumination). Certain parameters from esophageal physiologic tests can help guide the management of GERD and predict outcomes. In this ACG clinical guideline, we used the Grading of Recommendations Assessment, Development and Evaluation process to describe performance characteristics and clinical value of esophageal physiologic tests and provide recommendations for their utilization in routine clinical practice.

Reflux Hypersensitivity: How to Approach Diagnosis and Management

PURPOSE OF REVIEW

This paper aims to review the definition and diagnostic criteria for reflux hypersensitivity and comment on the present and future management of this condition.

RECENT FINDINGS

In 2016, the Rome IV criteria redefined reflux hypersensitivity as characterized by typical reflux symptoms, absence of endoscopic mucosal disease, absence of pathologic gastroesophageal reflux, and positive symptom correlation between reflux and heartburn episodes. Though uncertain, TPRV1 receptors have been implicated in the pathophysiology of reflux hypersensitivity. Recent studies have shown neuromodulators like SSRIs, SNRIs, and TCAs may be the future of managing this condition. With the release of the Rome IV criteria and availability of continuous pH monitoring, the diagnosis of reflux hypersensitivity has become more streamlined. Though there is no definitive therapy for reflux hypersensitivity, several anti-secretory agents and neuromodulators have shown some efficacy in therapeutic trials. The lack of large-scale, randomized controlled trials, however, reinforces the need for further research into the pharmacotherapy of reflux hypersensitivity.

Esophageal physiology-an overview of esophageal disorders from a pathophysiological point of view

The esophagus serves the principal purpose of transporting food from the pharynx into the stomach. A complex interplay between nerves and muscle fibers ensures that swallowing takes place as a finely coordinated event. Esophageal function can be tested by a variety of methods, endoscopy, manometry, and reflux monitoring being some of the most important. Regarding pathophysiology, motor disorders, such as achalasia, often cause dysphagia and/or chest pain. Functional esophageal disorders are a heterogeneous group with hypersensitivity as a dominant pathophysiological factor. Gastroesophageal reflux disease often causes symptoms, such as heartburn and regurgitation, and a spectrum of disease, ranging from minimal mucosal damage visible only in the microscope to esophageal ulcers and strictures in the most severe cases. Eosinophilic esophagitis is an immune-mediated condition that can result in significant dysphagia and associated luminal narrowing. In the following, we will provide an overview of the most common esophageal disorders from a combined pathophysiological and clinical view.

Usefulness of Pep-Test for Laryngo-Pharyngeal Reflux: A Pilot Study in Primary Care

Background

Gastroesophageal reflux disease is a digestive disorder characterized by nausea, regurgitation, and heartburn. Gastroesophageal reflux is the primary cause of laryngeal symptoms, especially chronic posterior laryngitis. The best diagnostic test for this disease is esophageal impedance-pH monitoring; however, it is poorly employed owing to its high cost and invasiveness. Salivary pepsin measured using a lateral flow device (Pep-test) has been suggested as an indirect marker of laryngopharyngeal reflux (LPR). The present study tested the reliability of Pep-test in diagnosing LPR in uninvestigated primary care attenders presenting with chronic laryngeal symptoms, and evaluated the raw pepsin concentration in patients with LPR.

Methods

A multicenter, non-interventional pilot study was conducted on 86 suspected patients with LPR and 59 asymptomatic subjects as controls in three Italian primary care settings. A reflux symptom index questionnaire was used to differentiate patients with LPR (score >13) from controls (score <5). Two saliva samples were collected, and comparisons between the groups were performed using two-sided statistical tests, according to variable distributions.

Results

There was no statistical difference in the salivary pepsin positivity between LPR patients and controls, whereas the pepsin intensity value was higher in controls than in LPR patients.

Conclusion

A high prevalence of pepsin positivity was observed in asymptomatic controls. Pepsin measurement should not be considered as a diagnostic test for LPR in primary care patients.

Measurement of Esophageal Nocturnal Baseline Impedance: A Simplified Method

Background/Aims

Mean nocturnal baseline impedance (MNBI) during multichannel intraluminal impedance pH-monitoring (MII-pH) reflects the status of esophageal mucosal integrity. MNBI is suggested as an adjunctive method to distinguish patients with true gastroesophageal reflux disease (GERD) from functional heartburn (FH) and might predict outcomes for anti-reflux treatment. However, current methodology for calculation of MNBI is time-consuming and subject to operator-dependent selection bias. We aim to simplify and provide a more objective method to calculate MNBI.

Methods

We retrospectively analyzed 100 MII-pH tracings from 20 patients with erosive reflux disease, 20 with non-erosive reflux disease (NERD), 20 with reflux hypersensitivity, 20 with functional heartburn (FH), and 20 healthy asymptomatic volunteers. We compared the current “conventional” MNBI analysis with our “simple” MNBI analysis measured by selecting the whole supine period using the impedance average calculation function in the MII-pH software.

Results

Absolute values were very similar and there was a strong correlation between conventional and simple MNBI values in the most distal channel in all groups (r ≥ 0.8, P < 0.001) including patients with increased supine acid reflux. Distal esophageal simple MNBI negatively correlated with acid exposure time (r = –0.695, P < 0.001). Patients with erosive reflux disease and NERD had lower simple MNBI values in the most distal channel compared to other groups (P < 0.001). With a cutoff value of 1785 ohms, simple MNBI can discriminate patients with GERD from those with reflux hypersensitivity and FH (sensitivity 80.0% and specificity 89.7%).

Conclusion

Simple MNBI analysis provides very similar values and has an excellent correlation with conventional MNBI analysis.

Phenotypes of Gastroesophageal Reflux Disease: Where Rome, Lyon, and Montreal Meet

Gastroesophageal reflux disease (GERD) is now one of the most common diagnoses made in a gastroenterology practice. From a conventional pathophysiological perspective, GERD is conceptualized as incompetence of the antireflux barrier at the esophagogastric junction; the more severe that incompetence, the worse the disease. However, it is increasingly clear that many presentations of GERD represent distinct phenotypes with unique predisposing cofactors and pathophysiology outside of this paradigm. Three major consensus initiatives have grappled with this dilemma (the Montreal Consensus, The Rome Foundation, and the Lyon Consensus), each from a different perspective. Montreal struggled to define the disease, Rome sought to characterize its functional attributes, while Lyon examined its physiological attributes. Here, we merge the 3 perspectives, developing the concept that what has come to be known as GERD is actually a family of syndromes with a complex matrix of contributing pathophysiology. A corollary to this is that the concept of one size fits all to therapeutics does not apply, and that although escalating treatment with proton pump inhibitors (PPIs) may be pertinent to healing esophagitis, its applicability beyond that is highly questionable. Similarly, failing to recognize the modulating effects of anxiety, hypervigilance, and visceral and central hypersensitivity on symptom severity has greatly oversimplified the problem. That oversimplification has led to excessive use of PPIs for everything captured under the GERD umbrella and shown a broad spectrum of syndromes less amenable to PPI therapy in any dose. It is with this in mind that we delineate this precision medicine concept of GERD.

Antireflux mucosectomy band in treatment of refractory gastroesophageal reflux disease: a pilot study for safety, feasibility and symptom control

Background and study aims  Antireflux mucosectomy band ligation (ARM-b) is an endoscopic procedure that mimics a fundoplication for managing gastroesophoageal reflux disease (GERD). The aim of this study was to assess safety and feasibility of ARM-b. Patients and methods  This was a single-center study on consecutive patients operated between June 2017 and January 2019 with refractory GERD, confirmed with pH-metry and without motility disorder at high-resolution manometry. A piecemeal mucosectomy of three quarters of circumference of esophagogastric junction was performed using a band ligation system and a hexagonal snare. The primary objective was to assess procedural safety and feasibility. The secondary objective was to document the clinical improvement at 3 and 6 months based on patient satisfaction, proton pump inhibitor (PPI) intake, symptoms, and quality of life scores. Results  Twenty-onepatients (11 men) with mean age 56.9 ± 14.4 years were analyzed. The technical success rate was 100 % (mean duration 35 ± 11 min). Four patients (19 %) had mild adverse events: one delayed bleeding at Day 1 managed conservatively, and three dysphagia endoscopically managed. Mean follow-up was 10 ± 5 months. Decrease/discontinuation of PPI intake was 76 % at 3 months and 72 % at 6 months. Improvement in mean symptoms and quality of life scores (GERD-Q and GERD-HQL) were statistically significant. One patient required laparoscopic fundoplication after ARM-b failure without complication. Conclusion  ARM-b is safe, feasible, and symptom-effective for treating refractory GERD, and it can be performed in the ambulatory setting. Further prospective studies are required to confirm these promising outcomes.

Stretta procedure versus proton pump inhibitors for the treatment of nonerosive reflux disease: A 6-month follow-up

To compare the Stretta procedure with proton pump inhibitors for the treatment of nonerosive reflux disease (NERD).From July 2018 to April 2019, patients diagnosed with NERD and referred for treatment were enrolled. They were treated with either Stretta procedure or proton pump inhibitor (PPI) medication and followed-up for 6 months. The symptom control, quality of life, lower esophageal sphincter (LES) pressure, 24-hour pH parameters, PPI usage and satisfaction rate were evaluated. The complications were assessed. The outcomes of the 2 groups were analyzed and compared.Twenty-eight patients in the Stretta group and 21 patients in the PPI group completed the 6-month follow-up. No severe adverse events occurred in both groups. Both interventions were effective in improvement of symptom and quality of life. The symptom score improvement was significantly superior in the Stretta group compared to the PPI group (6.3 ± 3.4 vs 8.5 ± 4.1, P = .03). LES pressure increased significantly in the Stretta group compared to the PPI group (14.2 ± 4.4 mm Hg vs 10.0 ± 4.0 mm Hg, P < .01). Although both interventions improved 24-hour pH parameters, including number of acid episodes (P = .27), acid exposure time (P = .39), and DeMeester score (P = .28), no difference was found between the 2 groups. Complete PPI cessation rate (82% vs 52%, P = .03) as well as satisfaction rate (89% vs 57%, P = .02) was much higher in Stretta group than those in the PPI groupThe Stretta procedure was safe and effective in the short term for the management of NERD. The Stretta procedure resulted in higher LES pressure and achieved better improvement of symptom control and PPI cessation than did PPI in the short term.

British Society of Gastroenterology guidelines for oesophageal manometry and oesophageal reflux monitoring

These guidelines on oesophageal manometry and gastro-oesophageal reflux monitoring supersede those produced in 2006. Since 2006 there have been significant technological advances, in particular, the development of high resolution manometry (HRM) and oesophageal impedance monitoring. The guidelines were developed by a guideline development group of patients and representatives of all the relevant professional groups using the Appraisal of Guidelines for Research and Evaluation (AGREE II) tool. A systematic literature search was performed and the GRADE (Grading of Recommendations Assessment, Development and Evaluation) tool was used to evaluate the quality of evidence and decide on the strength of the recommendations made. Key strong recommendations are made regarding the benefit of: (i) HRM over standard manometry in the investigation of dysphagia and, in particular, in characterising achalasia, (ii) adjunctive testing with larger volumes of water or solids during HRM, (iii) oesophageal manometry prior to antireflux surgery, (iv) pH/impedance monitoring in patients with reflux symptoms not responding to high dose proton pump inhibitors and (v) pH monitoring in all patients with reflux symptoms responsive to proton pump inhibitors in whom surgery is planned, but combined pH/impedance monitoring in those not responsive to proton pump inhibitors in whom surgery is planned. This work has been endorsed by the Clinical Services and Standards Committee of the British Society of Gastroenterology (BSG) under the auspices of the oesophageal section of the BSG.

Role of Reflux in the Pathogenesis of Eosinophilic Esophagitis: Comprehensive Appraisal With Off- and On PPI Impedance-pH Monitoring

OBJECTIVES

Role of reflux and mechanisms of response to proton pump inhibitor (PPI) therapy in eosinophilic esophagitis (EoE) have not yet been fully elucidated. Comprehensive assessment by impedance-pH monitoring could clarify these issues.

METHODS

Prospective multicenter study comparing EoE patients with healthy controls and gastroesophageal reflux disease cases. Patients with EoE were evaluated off- and on PPI; responsiveness was assessed by histology. Impedance-pH appraisal included chemical clearance, assessed with the postreflux swallow-induced peristaltic wave (PSPW) index, and mucosal integrity measured with mean nocturnal baseline impedance (MNBI).

RESULTS

Sixty consecutive patients with EoE were compared with 60 age- and sex-matched healthy controls and 60 subjects with gastroesophageal reflux disease. The number of total refluxes was higher, while the PSPW index was lower in patients with EoE than in healthy controls. Off PPI, a lower MNBI gradient between the mid and distal esophagus distinguished 20 patients with PPI-refractory EoE from 40 patients with PPI-responsive EoE and was a predictor of PPI failure. On PPI, a lower PSPW index was the sole reflux parameter distinguishing PPI-refractory from PPI-responsive EoE; all reflux parameters improved in PPI-responsive patients, whereas the PSPW index was not modified in PPI-refractory cases and was independently associated with PPI-responsiveness. MNBI in the distal and mid esophagus improved much more in PPI-responsive than in PPI-refractory EoE.

DISCUSSION

Reflux plays a role in the pathogenesis of EoE, more relevant in PPI-responsive cases. Low impedance gradient between the mid and distal esophagus may be useful to predict PPI refractoriness. PPIs mainly act by improving chemical clearance, i.e., by an antireflux action supporting long-term prescription in PPI-responsive EoE.

Prevalence of gastroesophageal reflux and risk factors for erosive esophagitis in obese patients considered for bariatric surgery

BACKGROUND

Gastroesophageal reflux disease (GERD) is common in obese individuals. Prospective studies investigating validated GERD questionnaires and clinical parameters at identifying erosive esophagitis (EE) in this population are limited.

OBJECTIVE

To prospectively evaluate the prevalence of GERD in obese patients considered for bariatric surgery and identify risk and predictive factors for EE.

METHODS

Eligible patients completed two validated questionnaires: GERDQ and Nocturnal Symptom Severity Impact (N-GSSIQ) before routine esophagogastroduodenoscopy.

RESULTS

242 consecutive patients were enrolled (130 females; mean age 37.8 ± 11.8 years; mean BMI 40.4 ± 5.3 kg/m²). The overall prevalence of gastroesophageal reflux (GERDQ ≥ 8, EE and/or PPI use) was 62.4%. EE was identified in 82 patients (33.9%) including 13/62 (21.0%) receiving PPIs at baseline. Multivariate logistic regression identified GERDQ ≥ 8 (OR = 6.3, 95%CI 3.0-13.1), hiatal hernia (OR = 4.2, 95%CI 1.6-10.7), abnormal Hill grade (OR = 2.7, 95%CI 1.4-5.4), and tobacco use (OR = 2.5, 95%CI 1.2-4.9) as independent risk factors for EE. A pre-endoscopic composite assessment including GERDQ ≥ 8 and presence of severe nocturnal reflux symptoms had 90% specificity and 20.7% sensitivity in identifying EE (NPV 68.9% and PPV 51.5%).

CONCLUSION

GERD is highly prevalent in obese patients. Anthropometric data and GERD questionnaires have limited accuracy at predicting erosive disease. Pre-operative endoscopic assessment in this population appears warranted.

Gastroesophageal reflux disease, obesity and laparoscopic sleeve gastrectomy: The burning questions

Obesity is a global health epidemic with considerable economic burden. Surgical solutions have become increasingly popular following technical advances leading to sustained efficacy and reduced risk. Sleeve gastrectomy accounts for almost half of all bariatric surgeries worldwide but concerns regarding its relationship with gastroesophageal reflux disease (GERD) has been a topic of debate. GERD, including erosive esophagitis, is highly prevalent in the obese population. The role of pre-operative endoscopy in bariatric surgery has been controversial. Two schools of thought exist on the matter, one that believes routine upper endoscopy before bariatric surgery is not warranted in the absence of symptoms and another that believes that symptoms are poor predictors of underlying esophageal pathology. This debate is particularly important considering the evidence for the association of laparoscopic sleeve gastrectomy (LSG) with de novo and/or worsening GERD compared to the less popular Roux-en-Y gastric bypass procedure. In this paper, we try to address 3 burning questions regarding the inter-relationship of obesity, GERD, and LSG: (1) What is the prevalence of GERD and erosive esophagitis in obese patients considered for bariatric surgery? (2) Is it necessary to perform an upper endoscopy in obese patients considered for bariatric surgery? And (3) What are the long-term effects of sleeve gastrectomy on GERD and should LSG be done in patients with pre-existing GERD?

Idiopathic pulmonary fibrosis and GERD: links and risks

Gastroesophageal reflux disease (GERD) and idiopathic pulmonary fibrosis (IPF) are two pathological conditions often strictly related, even if a clear relationship of causality has not been demonstrated. GERD is a frequent comorbidity in IPF patients, as demonstrated using combined multichannel intraluminal impedance-pH, despite being mostly clinically silent. According to that, it has been hypothesized that microaspiration of gastric material may play a fundamental role in the fibrotic transformation of pulmonary parenchyma. In contrast, it cannot be excluded that IPF may favor GERD by increasing the negative intrathoracic pressure. Therefore, this relationship is uncertain as well as not univocal. Nevertheless, the latest international guidelines recommend the use of proton pump inhibitors (PPIs) in IPF based on several data showing that PPIs can stabilize lung function, reduce disease flares and hospitalizations. On the contrary, recent studies not only question the relevance of these results, but also associate the use of PPIs with an increased risk of lung infections and a negative prognostic outcome. The aim of this review is to analyze the possible links between GERD and IPF and their possible therapeutic implications, trying to translate this scientific evidence into useful information for clinical practice.

Updates in the field of non-esophageal gastroesophageal reflux disorder

Introduction: Gastroesophageal reflux disease (GERD) is one of the most prevalent conditions in Western Countries, normally presenting with heartburn and regurgitation. Extra-esophageal (EE) GERD manifestations, such as asthma, laryngitis, chronic cough and dental erosion, represent the most challenging aspects from diagnostic and therapeutic points of view because of their multifactorial pathogenesis and low response to proton pump inhibitors (PPIs). In fact, in the case of EE, other causes must by preventively excluded, but instrumental methods, such as upper gastrointestinal endoscopy and laryngoscopy, have low specificity and sensitivity as diagnostic tools. In the absence of alarm signs and symptoms, empirical therapy with a double-dose of PPIs is recommended as a first diagnostic approach. Subsequently, impedance-pH monitoring could help to define whether the symptoms are GERD-related. Areas covered: This article reviews the current literature regarding established and proposed EE-GERD, reporting on all available options for its correct diagnosis and therapeutic management. Expert opinion: MII-pH could help to identify a hidden GERD that causes EE. Unfortunately, standard MII-pH analysis results are often unable to define this association. New parameters such as the mean nocturnal baseline impedance and post-reflux swallow-induced peristaltic wave index may have an improved diagnostic yield, but prospective studies using impedance-pH are needed.