Factors Associated with Overlap between Functional Dyspepsia and Nonerosive Reflux Disease in Endoscopy-based Helicobacter pylori-uninfected Japanese Health Checkup Participants: A Prospective, Multicenter Cross-sectional Study.

Objective We assessed the factors associated with overlap between functional dyspepsia (FD) and nonerosive reflux disease (NERD) in endoscopy-based Helicobacter pylori-uninfected Japanese health checkup participants. Methods We utilized baseline data from 3,085 individuals who underwent upper endoscopy for health screening in a prospective, multicenter cohort study. The participants were asked to complete a questionnaire detailing their upper abdominal symptoms and lifestyle. Anxiety was assessed using the State-Trait Anxiety Inventory (STAI) score. FD, postprandial distress syndrome (PDS), and epigastric pain syndrome (EPS) were defined according to the Rome III criteria. NERD was defined as heartburn or regurgitation ≥1 day/week without erosive esophagitis. Results Of the 3,085 participants, 73 (2.4%), 97 (3.1%), and 84 (2.7%) had FD alone, NERD alone, and FD-NERD overlap, respectively. Factors associated with FD-NERD-overlap participants compared with participants with neither FD nor NERD were women [odds ratio (OR): 2.08, 95% confidence interval (CI): 1.24-3.52], body mass index (BMI) <18.5 (OR: 2.87, 95% CI: 1.56-5.07), alcohol consumption ≥20 g/day (OR: 1.85, 95% CI: 1.06-3.15), and a high STAI score (OR: 2.53, 95% CI: 1.62-4.00). Increasing age (OR: 1.06, 95% CI: 1.01-1.11) and EPS symptoms [pure EPS (OR: 3.67, 95% CI: 1.65-8.51) and PDS-EPS overlap (OR: 11.6, 95% CI: 4.09-37.2)] were associated with FD-NERD overlap vs. FD alone. Women (OR: 3.17, 95% CI: 1.47-7.04), BMI <18.5 (OR: 3.03, 95% CI: 1.04-9.90), and acid reflux symptoms ≥2 days a week (OR: 3.57, 95% CI: 1.83-7.14) were associated with FD-NERD overlap vs. NERD alone. Conclusion Understanding the clinical features of overlap between FD and NERD will lead to better management.

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.

Identification of Unique Transcriptomic Signatures and Hub Genes Through RNA Sequencing and Integrated WGCNA and PPI Network Analysis in Nonerosive Reflux Disease.

PURPOSE: Transcriptomic studies on gastroesophageal reflux disease are scarce, and gene expression signatures in nonerosive reflux disease (NERD) remain elusive. The aim of the study was to identify gene expression profiles and potential hub genes in NERD. PATIENTS AND METHODS: We performed RNA sequencing on biopsy samples from nine consecutive patients with NERD and six healthy controls. Differentially expressed genes (DEGs) were analysed with the DESeq2 R package. A DEG-based protein-protein interaction (PPI) network was constructed to filter hub genes using Cytoscape. Weighted gene coexpression network analysis (WGCNA) was conducted to identify the coexpression relationships of all modules and explore the relationship between gene sets and clinical traits. RESULTS: In total, 1195 DEGs were identified, including 649 upregulated and 546 downregulated genes involved in regulating the inflammatory response and epithelial cell differentiation. Overlap of the PPI and WGCNA networks identified five shared genes, namely, THY1, BMP2, LOX, KDR and MMP9, as candidate hub genes in NERD. Quantitative PCR analysis of the expression of these five genes confirmed the sequencing results. Receiver operating characteristic analyses indicated that these hub genes had diagnostic potential for NERD patients. Gene set enrichment analysis confirmed that each hub gene was closely associated with the pathophysiological processes of NERD. In addition, a regulatory network comprising 42 transcription factors (TFs), 28 miRNAs and 5 hub genes was established. CONCLUSION: The five core genes may be promising biomarkers of NERD. The TF/miRNA/hub gene network can improve the understanding of the molecular mechanisms underlying disease progression.

Washed microbiota transplantation reduces proton pump inhibitor dependency in nonerosive reflux disease.

BACKGROUND: The pathogenesis of gastroesophageal reflux disease (GERD) is closely associated with the intestinal bacteria composition and their metabolites. AIM: To investigate whether washed microbiota transplantation (WMT) improves symptoms of nonerosive reflux disease (NERD) with proton pump inhibitor (PPI) dependency. METHODS: Patients with recurrent NERD and PPI dependency at the First Affiliated Hospital of Guangdong Pharmaceutical University from 2017 to 2018 were included and divided into a WMT or PPI group treated with PPI with/without WMT. The endpoint was NERD symptom frequency evaluated 1 mo after WMT using reflux disease questionnaire (RDQ) and GERD questionnaire (GERDQ) scores, remission time, PPI dose, and the examination of intestinal mucosal barrier function. RESULTS: In the WMT (n = 15) and PPI (n = 12) groups, the total remission rate at 1 mo after treatment was 93.3% vs 41.7%. Compared with the PPI group, the WMT group showed better results in GERDQ (P = 0.004) and RDQ (P = 0.003) and in remission months (8 vs 2, P = 0.002). The PPI dose was reduced to some extent for 80% of patients in the WMT group and 33.3% in the PPI group. In 24 patients, intestinal mucosal barrier function was examined before treatment, and changes in the degree of damage were observed in 13 of these patients after treatment. Only one of the 15 patients had minor side effects, including a mushy stool two or three times a day, which resolved on their own after 1 wk. CONCLUSION: This study is the first to demonstrate that WMT may be safe and effective for relieving NERD symptoms and reducing PPI dependency and recurrence.

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.

The Ameliorating Effect of Switching to Vonoprazan: A Novel Potassium-Competitive Acid Blocker in Patients with Proton Pump Inhibitor Refractory Non-Erosive Reflux Disease.

INTRODUCTION: Weakly acidic reflux has been reported to be the major cause of symptoms in patients with proton pump inhibitor (PPI)-refractory nonerosive reflux disease (NERD) undergoing PPI treatment. We previously reported that reflux at pH 4-5 was the main factor that induced symptoms in such patients. The present study aimed to elucidate the symptom-ameliorating effect of vonoprazan (VPZ) by evaluating the change in the pH value of the refluxate using multichannel intraluminal impedance and pH (MII-pH) monitoring. METHODS: We retrospectively evaluated the records of MII-pH monitoring in 29 symptom index (SI) and/or symptom association probability (SAP)-positive patients with PPI-refractory NERD. After switching to VPZ 20 mg/day, we performed MII-pH monitoring again. We assessed the change in the score of the frequency scale for the symptoms of gastroesophageal reflux disease (FSSG), the pH value of the refluxate, and the percent times of intragastric pH <4 or <5 before and after switching. We divided the patients into the following 2 groups according to the FSSG score after switching: effective and noneffective groups. RESULTS: Among of the 29 SI/SAP-positive patients, 16 underwent switching to VPZ. Furthermore, of these 16 patients, 10 underwent MII-pH monitoring again after switching. The FSSG score decreased, the pH value of the refluxate increased, and the percent times of intragastric pH <4 or <5 reduced after switching when compared with the findings before switching. In the effective group, both the proportion of reflux at pH <4 and that of reflux at pH 4-5 decreased while taking VPZ when compared with the findings while taking double-dose PPI. In the noneffective group, the proportion of reflux at pH <4 decreased but that of reflux at pH 4-5 increased and that of reflux at pH <5 did not change overall while taking VPZ. In addition, the percent times of intragastric pH <5 values were low in the effective group. CONCLUSION: Symptom suppression appears to be inadequate in patients with persistent reflux at pH 4-5 even with VPZ 20 mg/day. Strong acid suppressive therapy with VPZ to increase the pH value of the refluxate to ≥5 is useful for symptom improvement.

Impaired Mucosal Integrity in Proximal Esophagus Is Involved in Development of Proton Pump Inhibitor-Refractory Nonerosive Reflux Disease.

BACKGROUND AND OBJECTIVE: Weakly acidic reflux reaching to the proximal esophagus is closely related to the perception of gastroesophageal reflux in patients with nonerosive reflux disease despite treatment with a proton pump inhibitor (PPI). However, little is known about the involvement of the patients' mucosal integrity of the proximal esophagus. METHODS: We recruited 15 symptomatic nonerosive gastroesophageal reflux disease (GERD) patients with a positive symptom index despite PPI treatment and 11 healthy asymptomatic volunteers as controls. The biopsy specimens obtained from the proximal and distal esophagus were applied to a mini-Ussing chamber system to measure transepithelial electrical resistance (TEER) against a pH 4 weak acid. The esophageal biopsy samples were subjected to quantitative real-time PCR and immunohistochemical analysis. RESULTS: In the proximal esophagus, the weak acid exposure reduced the TEER in the PPI-refractory patients compared to that in the controls. The frequency of the reflux extending to the proximal esophagus had a significant correlation with the reduction in the proximal esophageal TEER in the patients. The reduced TEER in the proximal esophagus was accompanied by an increase in IL-8 and IL-1ß mRNA and a decrease in occludin mRNA levels. The proximal esophageal mucosa in the patients presented infiltration of CD3-positive lymphocytes and an increased expression of solute carrier organic anion transporter family member 2A1 (SLCO2A1), a passage gate of reflux symptom-evoking molecules. CONCLUSIONS: The reflux perception is related to an impairment of the proximal esophageal mucosal integrity in patients with nonerosive reflux disease despite PPI.

Gastroesophageal reflux disease in pediatric esophageal atresia: Assessment of clinical symptoms and pH-impedance data.

BACKGROUND: Esophageal atresia (EA) is the most common congenital anomaly of the gastrointestinal tract. Gastroesophageal reflux disease (GERD) is a frequent and lifelong problem in these patients. GERD can be asymptomatic and the incidence of esophageal gastric and intestinal metaplasia (Barrett's esophagus) is increased in adults with EA compared with the general population. Timely and accurate diagnosis of GERD is important to reduce long-term problems and this may be achieved by pH-impedance testing. AIM: To assess symptoms and pH-impedance data in children after EA, in order to identify their specific features of GERD. METHODS: This study was conducted from November 2017 to February 2020 and involved 37 children who had undergone EA via open surgical repair (51.35% boys, 48.65% girls; age range: 1-14 years, median: 4.99 years). GERD diagnosis was made based on multichannel intraluminal impedance/pH study and two groups were established: EA without GERD, n = 17; EA with GERD, n = 20. A control group was established with 66 children with proven GERD (68.18% boys, 31.82% girls; median age: 7.21 years), composed of a nonerosive reflux disease (referred to as NERD) group (n = 41) and a reflux esophagitis group (n = 25). Upper gastrointestinal endoscopy with a mucosal esophageal biopsy was performed on all patients. RESULTS: The most frequently observed symptom in EA patients with GERD and without GERD was cough (70% and 76.5% respectively). The number of patients with positive symptom association probability in the EA groups was significantly larger in the EA without GERD group (P = 0.03). In the control reflux esophagitis group, prevalence of gastrointestinal symptoms was significantly higher than in the NERD group (P = 0.017). For both EA groups, there was strong correlation with index of proximal events (IPE) and total proximal events (EA with GERD: 0.96, P < 0.001; EA without GERD: 0.97, P < 0.001) but level of IPE was significantly lower than in GERD patients without any surgical treatment (P < 0.001). Data on distal mean nocturnal baseline impedance were significantly different between the EA with GERD group (P < 0.001) and the two control groups but not between EA without GERD and the two control groups. CONCLUSION: Mean nocturnal baseline impedance may have diagnostic value for GERD in EA children after open surgical repair. IPE might be an additional parameter of pH-impedance monitoring.

[Esophageal disorders in patients with irritable bowel syndrome].

AIM: To study the whole range of esophageal disorders in patients with irritable bowel syndrome (IBS) using high-tech methods. MATERIALS AND METHODS: 102 IBS patients (47 males, mean age 40.8, diagnosis of IBS was established according to Rome III criteria) with esophageal symptoms (heartburn, belching, globus sensation and noncardiac chest pain) were examined in gastroenterology department. All patients underwent endoscopy, with biopsies if required, X-ray examination of upper gastrointestinal tract; 24-hour pH-impedance monitoring;13C-urea breath test. Evaluation of esophageal symptoms was carried out on the basis of Rome IV criteria. RESULTS: 21 (20.6%) individuals had esophagitis (ERD). According to 24-hour pH-monitoring data, 7 of them had overlap between GERD and functional esophageal disorders (FED). 27 (26.5%) individuals had nonerosive reflux disease (NERD). In 54 (52.9%) individuals endoscopy and pH-impedance monitoring data did not differ from normal, suggesting this group as group of patients with FED. There was no significant difference for age, sex and IBS subtypes in GERD, NERD and FED groups. CONCLUSION: Comorbid esophageal disorders in patients with IBS are different and represented by organic diseases, FED and overlap between them. Methods such as 24-h pH-impedance measurement and esophageal manometry should be used to assess comorbid esophageal disorders in IBS patients.

AGA Clinical Practice Update on Functional Heartburn: Expert Review.

BEST PRACTICE ADVICE 1: A diagnosis of functional heartburn should be considered when retrosternal burning pain or discomfort persists despite maximal (double-dose) proton pump inhibitor (PPI) therapy taken appropriately before meals during a 3-month period. BEST PRACTICE ADVICE 2: A diagnosis of functional heartburn requires upper endoscopy with esophageal biopsies to rule out anatomic and mucosal abnormalities, esophageal high-resolution manometry to rule out major motor disorders, and pH monitoring off PPI therapy (or pH-impedance monitoring on therapy in patients with proven gastroesophageal reflux disease [GERD]), to document physiologic levels of esophageal acid exposure in the distal esophagus with absence of reflux-symptom association (ie, negative symptom index and symptom association probability). BEST PRACTICE ADVICE 3: Overlap of functional heartburn with proven GERD is diagnosed according to Rome IV criteria when heartburn persists despite maximal PPI therapy in patients with history of proven GERD (ie, positive pH study, erosive esophagitis, Barrett's esophagus, or esophageal ulcer), and pH impedance testing on PPI therapy demonstrates physiologic acid exposure without reflux-symptom association (ie, negative symptom index and symptom association probability). BEST PRACTICE ADVICE 4: PPIs have no therapeutic value in functional heartburn, the exception being proven GERD that overlaps with functional heartburn. BEST PRACTICE ADVICE 5: Neuromodulators, including tricyclic antidepressants, selective serotonin reuptake inhibitors, tegaserod, and histamine-2 receptor antagonists have benefit as either primary therapy in functional heartburn or as add-on therapy in functional heartburn that overlaps with proven GERD. BEST PRACTICE ADVICE 6: Based on available evidence, acupuncture and hypnotherapy may have benefit as monotherapy in functional heartburn, or as adjunctive therapy combined with other therapeutic modalities. BEST PRACTICE ADVICE 7: Based on available evidence, anti-reflux surgery and endoscopic GERD treatment modalities have no therapeutic benefit in functional heartburn and should not be recommended.

[PREVALENCE OF FUNCTIONAL DYSPEPSIA SYMPTOMS IN PATIENTS WITH ASTHMA].

BACKGROUND: Gastroesophageal reflux disease (GERD) is a common comorbidity among patients with asthma. In addition, functional dyspepsia (FD) is characterized by upper abdominal symptoms without organic disease manifestations. However, the prevalence of FD among patients with asthma remains uninvestigated; therefore, herein, we investigated the prevalence of dyspepsia symptoms in these patients. METHODS: We recruited 156 patients with asthma from the outpatient clinic of Teikyo University Hospital and investigated the prevalence of dyspepsia symptoms using the modified Frequency Scale for the Symptoms of GERD. Further, the relationship between dyspepsia symptoms and clinical background of asthma was also investigated. RESULTS: Certain digestive organ symptoms were exhibited by 83% of patients with asthma, dyspepsia symptoms by 44%, and reflux symptoms by 26%. The dyspepsia-dominant group showed significantly higher female ratio and numerically lower %FEV1 than the asymptomatic group. In the group with dyspepsia score >5 points, the ratio of patients undergoing step 4 asthma treatment and the ratio of those using long-acting muscarinic receptor antagonist were higher than those in the group with a score <5 points. Furthermore, endoscopic diagnosis was also made in 84 patients and the prevalence of FD was 21%. CONCLUSION: A considerable proportion of patients with asthma exhibited dyspepsia symptoms, and the asthma severity in patients with dyspepsia was higher than those in asymptomatic patients. Based on the current findings, more attention should be directed to FD, in addition to GERD, as a comorbidity of the digestive system in patients with asthma.

The Spectrum of Reflux Phenotypes.

The focus on a symptom-based definition for gastroesophageal reflux disease (GERD) in adults and children has contributed to widespread use of acid suppression medications in patients with so-called typical reflux symptoms to treat the possibility of acid-mediated disease. Diagnostic testing with upper endoscopy, esophageal biopsies, ambulatory reflux monitoring, and/or esophageal manometry is often pursued when patients do not respond optimally to these medications. By using information from this diagnostic testing, GERD has shifted from a single diagnosis to a phenotypic spectrum, and each phenotype has unique pathophysiologic mechanisms driving symptom perception. Understanding these mechanisms is important to tailor individualized treatment plans and guide therapeutic interventions. The aim of this article is to discuss the different reflux phenotypes, the utility of esophageal reflux testing, the mechanisms underlying symptoms, and the management strategies for each phenotype.

Antireflux surgery is equally beneficial in nonerosive and erosive gastroesophageal reflux disease.

PURPOSE: Although nonerosive and erosive gastroesophageal reflux disease (GERD) have similar symptom severity, nonerosive reflux disease (NERD) is considered a milder type of GERD and gastroenterologists have hesitated to refer these patients for antireflux surgery. The aim of this study was to compare surgical outcomes of antireflux surgery between patients with NERD and erosive reflux disease (ERD). METHODS: Seventy patients met the inclusion criteria of this study among a total of 117 patients who underwent antireflux surgery from November 2012 to October 2017. According to preoperative endoscopy, patients were classified into NERD group (minimal changes or no esophagitis) and ERD group. Clinical characteristics and surgical outcomes were compared between NERD and ERD. RESULTS: There were 26 patients in NERD group and 44 patients in ERD group. The male:female ratio was higher in the ERD group than in the NERD group (P = 0.044). Preoperative symptoms, response to acid suppressive medication, acid exposure on pH monitoring study, and esophageal manometry results were similar in the 2 groups. Reflux on barium esophagography was more frequently observed in ERD (77.3%) than in NERD (50.0%, P = 0.019). At 6 months after surgery, complete resolution and partial improvement of GERD symptoms were similar in the 2 groups (80.8% and 15.4%, respectively, in NERD vs. 88.6% and 2.3%, respectively, in ERD; P = 0.363). CONCLUSION: Laparoscopic Nissen fundoplication is equally beneficial to patients with NERD and ERD. Antireflux surgery should not be avoided for GERD patients without mucosal breaks on endoscopy as the evidence of erosive esophagitis.

Nonerosive reflux disease: clinical concepts.

Esophageal symptoms can arise from gastroesophageal reflux disease (GERD) as well as other mucosal and motor processes, structural disease, and functional esophageal syndromes. GERD is the most common esophageal disorder, but diagnosis may not be straightforward when symptoms persist despite empiric acid suppressive therapy and when mucosal erosions are not seen on endoscopy (as for nonerosive reflux disease, NERD). Esophageal physiological tests (ambulatory pH or pH-impedance monitoring and manometry) can be of value in defining abnormal reflux burden and reflux-symptom association. NERD diagnosed on the basis of abnormal reflux burden on ambulatory reflux monitoring is associated with similar symptom response from antireflux therapy for erosive esophagitis. Acid suppression is the mainstay of therapy, and antireflux surgery has a definitive role in the management of persisting symptoms attributed to NERD, especially when the esophagogastric junction is compromised. Adjunctive approaches and complementary therapy may be of additional value in management. In this review, we describe the evaluation, diagnosis, differential diagnosis, and management of NERD.

Juice Test for Identification of Nonerosive Reflux Disease in Heartburn Patients.

BACKGROUND/AIMS: Evaluation of esophageal clearance by orange juice swallowing could be useful to identify different categories of gastroesophageal reflux disease. We determined whether a juice test at the beginning of esophageal pH monitoring can identify nonerosive reflux disease (NERD) among heartburn patients. METHODS: Multiple swallows of orange juice (pH 3) were performed at the beginning of esophageal pH monitoring in 71 heartburn patients off acid-suppressive therapy. The area between pH drop below 5 and recovery to 5 was calculated from pH tracings and named Delta5 (mmol∙L⁻¹âˆ™sec). Fifteen healthy subjects served to determine Delta5 cutoff (95th percentile). Patients were classified as NERD, non-NERD (a mix of reflux hypersensitivity, functional heartburn, and undetermined), and erosive disease depending on acid exposure, reflux symptom analysis, and upper endoscopy. RESULTS: Delta5 cutoff in healthy subjects was 251 mmol·L⁻¹âˆ™sec. Among 71 patients, 23 had NERD, 26 had non-NERD, and 22 had erosive disease. Compared to non-NERD, Delta5 was higher in both NERD (median [interquartile range]: 316 [213-472] vs 165 [105-225]; P ＜ 0.01) and erosive disease (310 [169-625] vs 165 [105-225]; P ＜ 0.01). An elevated Delta5 (＞ 251 mmol∙L⁻¹âˆ™sec) showed sensitivity of 74% and specificity of 81% for identification of NERD. Positive and negative likelihood ratios were 3.84 and 0.32 respectively, whereas test accuracy was 78%. CONCLUSIONS: A juice test with calculation of Delta5 helps in the identification of true NERD among heartburn patients with endoscopy-negative reflux disease. In these patients, an elevated Delta5 could make prolonged reflux testing unnecessary.

Evaluation of Esophageal Mucosal Integrity in Patients with Gastroesophageal Reflux Disease.

BACKGROUND: Impaired esophageal mucosal integrity plays a role in causing symptoms of gastroesophageal reflux disease (GERD). Recently, the assessment of esophageal baseline impedance (BI) using the multichannel intraluminal impedance-pH (MII-pH) test was suggested as a surrogate technique for the study of esophageal mucosal integrity and was reported to be useful in distinguishing GERD from non-GERD. However, measuring BI requires a 24-h testing period, is complicated, and causes considerable patient discomfort. SUMMARY: Recently, endoscopy-guided catheters that can measure mucosal impedance (MI) and mucosal admittance (MA), which is the inverse of impedance, were developed, and their usefulness in measuring MI and MA for the diagnosis of GERD has been reported. In these studies, esophageal MI values were significantly lower in patients with GERD than in those without GERD. In contrast, esophageal MA was significantly higher in patients with GERD than in those without. Furthermore, we reported that MA is inversely correlated with BI and correlated with acid exposure time. Key Messages: Endoscopy-guided real-time measurement of MI and MA may allow the estimation of mucosal integrity and may be a useful diagnostic tool for patients with GERD in a manner similar to 24-h MII-pH monitoring.

Differences in salivary secretory function between patients with erosive esophagitis and those with nonerosive reflux disease.

BACKGROUND AND AIM: It has been speculated that impaired salivary flow contributes to abnormal acid clearance in patients with erosive esophagitis (EE). For easy and objective assessment of salivary function, we developed a salivary gland blood flow measurement technique using continuous-wave Doppler sonography. In the present study, we evaluated the salivary secretory function in patients with EE and those with nonerosive reflux disease (NERD) using this method. METHODS: Doppler waveform analysis was performed on the facial artery to assess blood inflow to the submandibular gland of 30 healthy subjects (HS). Blood flow was compared before and after secretory stimulation with 1 mL of lemon juice. Saliva was simultaneously collected and weighed before and after stimulation. Continuous-wave Doppler sonography was also performed in patients with EE and NERD. The size of the submandibular gland was compared in 26 patients with EE, 41 patients with NERD, and 86 HS. RESULTS: The submandibular gland blood flow increased after stimulation in all HS. Both within-day and day-to-day reproducibility were good. There was a significant correlation between the percent increase in the maximum velocity and the percent increase in salivary secretion. Although the size of the submandibular gland was not significantly different among the three groups, the percent increase in the maximum velocity in patients with EE was significantly smaller than that in HS. CONCLUSIONS: We have established an easy method of assessing salivary function in daily practice. This study revealed that a decrease in salivary secretory function is involved in the pathology of EE.

Antireflux surgery is equally beneficial in nonerosive and erosive gastroesophageal reflux disease

PURPOSE: Although nonerosive and erosive gastroesophageal reflux disease (GERD) have similar symptom severity, nonerosive reflux disease (NERD) is considered a milder type of GERD and gastroenterologists have hesitated to refer these patients for antireflux surgery. The aim of this study was to compare surgical outcomes of antireflux surgery between patients with NERD and erosive reflux disease (ERD). METHODS: Seventy patients met the inclusion criteria of this study among a total of 117 patients who underwent antireflux surgery from November 2012 to October 2017. According to preoperative endoscopy, patients were classified into NERD group (minimal changes or no esophagitis) and ERD group. Clinical characteristics and surgical outcomes were compared between NERD and ERD. RESULTS: There were 26 patients in NERD group and 44 patients in ERD group. The male:female ratio was higher in the ERD group than in the NERD group (P = 0.044). Preoperative symptoms, response to acid suppressive medication, acid exposure on pH monitoring study, and esophageal manometry results were similar in the 2 groups. Reflux on barium esophagography was more frequently observed in ERD (77.3%) than in NERD (50.0%, P = 0.019). At 6 months after surgery, complete resolution and partial improvement of GERD symptoms were similar in the 2 groups (80.8% and 15.4%, respectively, in NERD vs. 88.6% and 2.3%, respectively, in ERD; P = 0.363). CONCLUSION: Laparoscopic Nissen fundoplication is equally beneficial to patients with NERD and ERD. Antireflux surgery should not be avoided for GERD patients without mucosal breaks on endoscopy as the evidence of erosive esophagitis.

The Prevalence of Rome IV Nonerosive Esophageal Phenotypes in Children.

OBJECTIVES: To assess the prevalence of Rome IV nonerosive esophageal phenotypes in children using multichannel intraluminal impedance testing and to describe the rates of proton pump inhibitor (PPI) responsiveness and the frequency of microscopic esophagitis in these patients. STUDY DESIGN: We conducted a retrospective review of all children ≥5 years of age who underwent esophagogastroduodenoscopy and multichannel intraluminal impedance testing off PPI therapy for evaluation of typical gastroesophageal reflux symptoms. Only children with symptoms during the multichannel intraluminal impedance testing were included. Children were categorized into the following nonerosive esophageal phenotypes using Rome IV criteria: nonerosive reflux disease, reflux hypersensitivity, and functional heartburn. Rates of esophagitis and responsiveness to acid suppression therapy were assessed. RESULTS: Forty-five children were included: 27% were categorized as having nonerosive reflux disease, 29% with reflux hypersensitivity (27% acid and 2% nonacid), and 44% with functional heartburn. Older children reported significantly more heartburn (P < .001) than younger children, whereas younger children were more likely to report nonspecific pain (P = .047). There were no differences between groups in other reflux symptoms, rates of responsiveness to PPIs, or the presence of microscopic esophagitis on biopsy. CONCLUSIONS: Functional heartburn is the most common Rome IV nonerosive esophageal phenotype in children. Neither microscopic esophagitis nor PPI responsiveness can predict phenotype in pediatric patients.

A novel murine model of esophageal nonerosive reflux disease: from inflammation to impairment in mucosal integrity.

Nonerosive reflux disease (NERD) is a highly prevalent phenotype of the gastroesophageal reflux disease. In this study, we developed a novel murine model of NERD in mice with microscopic inflammation and impairment in the epithelial esophageal barrier. Female Swiss mice were subjected to the following surgical procedure: the transitional region between the forestomach and the glandular portion of the stomach was ligated, and a nontoxic ring was placed around the duodenum near the pylorus. The control group underwent sham surgery. The animals were euthanized at 1, 3, 7, and 14 days after surgery. Survival and body weight were monitored daily. Esophageal wet weight, macroscopic lesion, histopathological alterations, myeloperoxidase (MPO) activity, cytokine levels, transepithelial electrical resistance (TEER), and mucosal permeability were evaluated. The survival rate was 78% at 14 days, with mild loss in body weight. Surgery did not induce erosive esophagitis but instead induced microscopic inflammation and increased esophageal wet weight, IL-6, keratinocyte-derived cytokine (KC) levels, and MPO activity with maximal peak between 3 and 7 days and resolution at 14 days postsurgery. Epithelial esophageal barrier was evaluated in operated mice at 7 and 14 days postsurgery; a decrease in TEER and increase in the esophageal epithelial permeability were observed compared with the sham-operated group. In addition, the inhibition of acid secretion with omeprazole significantly prevented the esophageal inflammation and impairment of barrier function at 7 days postsurgery. Thus we established a novel experimental model of NERD in mice, which can contribute to understanding the pathophysiological events associated with NERD.NEW & NOTEWORTHY In this study, we standardized an experimental model of nonerosive reflux disease (NERD) in mice. This model involves an acute inflammatory response followed by impaired esophageal mucosal integrity, even in the absence of inflammation. Thus this model can serve for evaluation of pathophysiological aspects of NERD and open new perspectives for therapeutic strategies for patients with this disorder.