Weakly Acid Reflux Research Articles

Global Transcriptomic Analysis of Topical Sodium Alginate Protection against Peptic Damage in an In Vitro Model of Treatment-Resistant Gastroesophageal Reflux Disease.

Breakthrough symptoms are thought to occur in roughly half of all gastroesophageal reflux disease (GERD) patients despite maximal acid suppression (proton pump inhibitor, PPI) therapy. Topical alginates have recently been shown to enhance mucosal defense against acid-pepsin insult during GERD. We aimed to examine potential alginate protection of transcriptomic changes in a cell culture model of PPI-recalcitrant GERD. Immortalized normal-derived human esophageal epithelial cells underwent pretreatment with commercial alginate-based anti-reflux medications (Gaviscon Advance or Gaviscon Double Action), a matched-viscosity placebo control, or pH 7.4 buffer (sham) alone for 1 min, followed by exposure to pH 6.0 + pepsin or buffer alone for 3 min. RNA sequencing was conducted, and Ingenuity Pathway Analysis was performed with a false discovery rate of ≤0.01 and absolute fold-change of ≥1.3. Pepsin-acid exposure disrupted gene expressions associated with epithelial barrier function, chromatin structure, carcinogenesis, and inflammation. Alginate formulations demonstrated protection by mitigating these changes and promoting extracellular matrix repair, downregulating proto-oncogenes, and enhancing tumor suppressor expression. These data suggest molecular mechanisms by which alginates provide topical protection against injury during weakly acidic reflux and support a potential role for alginates in the prevention of GERD-related carcinogenesis.

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

Laparoscopic sleeve gastrectomy (LSG) is a popular weight loss procedure with potential effects on gastroesophageal reflux disease (GERD). However, research on the association between LSG and GERD using objective evaluation criteria, such as multichannel intraluminal impedance combined with pH testing (MII-pH), is limited. This study aimed to investigate the impact of LSG on GERD using MII-pH and current consensus guidelines. It was conducted as a prospective clinical study on 33 patients who underwent LSG between January 2022 and August 2022. MII-pH and high-resolution manometry were performed preoperatively and 3 to 6 months postoperatively. GERD diagnosis was based on MII-pH results using the Lyon and Update Porto consensus guidelines. Postoperative MII-pH analysis revealed a significant increase in acid reflux time, acid exposure time, reflux index, esophageal clearance, total reflux time, and longest reflux period. Weak acid reflux episodes decreased, while Demeester score and alkaline reflux showed nonsignificant increases. Pathologic reflux significantly increased postoperatively based on MII-pH diagnosis. High-resolution manometry showed a significant increase in unsuccessful motility. Although the Demeester score calculation consists of 6 metrics, including acid exposure time, the acid exposure time is more specific in detecting pathologic reflux. Pathologic GERD increases significantly with LSG in the early period. Therefore, preoperative and postoperative endoscopy and MII-pH can provide valuable information regarding the need for closer follow-up after LSG.

The Dubai Definition and Diagnostic Criteria of Laryngopharyngeal Reflux: The IFOS Consensus.

The objective of this work was to gather an international consensus group to propose a global definition and diagnostic approach of laryngopharyngeal reflux (LPR) to guide primary care and specialist physicians in the management of LPR. Forty-eight international experts (otolaryngologists, gastroenterologists, surgeons, and physiologists) were included in a modified Delphi process to revise 48 statements about definition, clinical presentation, and diagnostic approaches to LPR. Three voting rounds determined a consensus statement to be acceptable when 80% of experts agreed with a rating of at least 8/10. Votes were anonymous and the analyses of voting rounds were performed by an independent statistician. After the third round, 79.2% of statements (N = 38/48) were approved. LPR was defined as a disease of the upper aerodigestive tract resulting from the direct and/or indirect effects of gastroduodenal content reflux, inducing morphological and/or neurological changes in the upper aerodigestive tract. LPR is associated with recognized non-specific laryngeal and extra-laryngeal symptoms and signs that can be evaluated with validated patient-reported outcome questionnaires and clinical instruments. The hypopharyngeal-esophageal multichannel intraluminal impedance-pH testing can suggest the diagnosis of LPR when there is >1 acid, weakly acid or nonacid hypopharyngeal reflux event in 24 h. A global consensus definition for LPR is presented to improve detection and diagnosis of the disease for otolaryngologists, pulmonologists, gastroenterologists, surgeons, and primary care practitioners. The approved statements are offered to improve collaborative research by adopting common and validated diagnostic approaches to LPR. 5 Laryngoscope, 134:1614-1624, 2024.

A perspective on the clinical relevance of weak or nonacid reflux.

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. 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.

Is magnetic sphincter augmentation indicated in patients with laryngopharyngeal reflux?

Up to 30% of patients with gastroesophageal reflux disease (GERD) suffer from laryngopharyngeal reflux (LPR) with symptoms, as chronic cough, laryngitis, or asthma. Besides life-style modifications and medical acid suppression, laparoscopic fundoplication is an established treatment option. Treatment-related side effects after laparoscopic fundoplication have to be weighted against LPR symptom control in 30-85% of patients after surgery. Magnetic sphincter augmentation (MSA) is described as an effective alternative to fundoplication for surgical treatment of GERD. However, evidence on the efficacy of MSA in patients with LPR is very limited. Preliminary data on the results of MSA treating LPR symptoms in patients with acid and weakly acid reflux are promising; showing comparable results to laparoscopic fundoplication by providing the potential of decrease side effects.

Study on the time-point distribution characteristics of the occurrence of laryngopharyngeal reflux

Objective: To investigate the characteristics of the time-point distribution of the occurrence of laryngopharyngeal reflux (LPR) by 24-hour multichannel intraluminal impedance-pH monitoring (24 h MII-pH) and to provide guidance for the development of individualized anti-reflux strategies for LPR patients. Methods: We conducted a retrospective analysis of 24 h MII-pH data from 408 patients [339 males and 69 females, aged 23-84 (55.08±11.08) years] attending the Department of Otorhinolaryngology Head and Neck Surgery at the Sixth Medical Center of the PLA General Hospital from January 2013 to March 2020. The number of gas acid/weak-acid reflux, mixed gas-liquid acid/weak-acid reflux, liquid acid/weak-acid reflux and alkaline reflux events at different time points were recorded and statistically analyzed through SPSS 26.0 software. Results: A total of 408 patients were included. Based on the 24 h MII-pH, the total positive rate of LPR was 77.45% (316/408). The type of positive gaseous weak-acid reflux was significantly higher than the remaining types of LPR (χ2=297.12,P<0.001). Except the gaseous weak-acid reflux, the occurrence of the remaining types of LPR showed a tendency to increase after meals, especially after dinner. Liquid acid reflux events occurred mainly between after dinner and the following morning, and 47.11% (57/121) of them occurred within 3 h after dinner. There was a significant positive association between Reflux Symptom Index scores and gaseous weak-acid reflux(r=0.127,P<0.01), liquid acid reflux(r=0.205,P<0.01) and liquid weak-acid reflux(r=0.103,P<0.05)events. Conclusions: With the exception of gaseous weak-acid reflux events, the occurrence of the remaining types of LPR events has a tendency to increase after meals, especially after dinner. Gaseous weak-acid reflux events accounts for the largest proportion of all types of LPR events, but the pathogenic mechanisms of gaseous weak-acid reflux are needed to further investigate.

Gastroesophageal reflux in children with recurrent and chronic respiratory diseases: non-acid or acid?

In some cases, gastroesophageal reflux (GER) may be accompanied by duodenogastric reflux, forming non-acid reflux, which has a certain influence on the clinical presentation and the response to anti-reflux therapy. The study aimed to determine the role of non-acid reflux in children with recurrent and chronic respiratory diseases (RCRD). All children with RCRD, for unknown reason, poorly responding to respiratory-specific therapy, hospitalized for gastroesophageal reflux disease (GERD) screening, using dual pH-multichannel intraluminal impedance (pH-MII). The study was conducted in 42 children at the age Me – 2.75; IQR 1.08-9.42. The most common type of reflux was weakly acid reflux - 62.25 [36.425-121.225], then acid - 34.05 [12.875-71.65], alkaline - 1.75 [0 - 12.375] episodes per day (p &lt;0.05). Non-acid reflux was more common in children with only respiratory symptoms - no esophageal manifestations of GERD. All types of refluxes were more often recorded in the upright compared to the supine position. In 70% patients, cough could be associated with reflux, while in 88% children reflux was non-acid (including 69% - weakly acid, 19% - alkaline), in 38% - acid. Non-acid reflux is the main type of GER in children with RCRD refractory to standard therapy, which could be associated with cough in this patient population.

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

The clinical management of nonacid gastroesophageal reflux-induced chronic cough (GERC) is challenging, and patient response to standard antireflux therapy (omeprazole 20 mg twice daily plus mosapride 10 mg thrice daily) is suboptimal. This study aimed to identify predictors of standard antireflux therapy efficacy and provide evidence for standardized management algorithms of nonacid GERC. A total of 115 nonacid GERC patients who underwent multichannel intraluminal impedance-pH monitoring (MII-pH) were enrolled between March 2017 and March 2021. Retrospective analysis of general information and MII-pH indications were used to establish a regression analysis model for multiple factors affecting standard antireflux therapy efficacy. 90 patients met the inclusion criteria, and the overall response rate to standard antireflux therapy was 55.5% (50/90). The mean nocturnal baseline impedance (MNBI) (1817.75 ± 259.26 vs. 2369.93 ± 326.35, P = 0.030) and proximal MNBI (1833.39 ± 92.16 vs. 2742.57 ± 204.64, P ≤ 0.001) of responders were lower than those of nonresponders. Weakly acid reflux (56.00 (31.70, 86.00) vs. 14.00 (14.00, 44.20), P = 0.022), nonacid reflux (61.35 (15.90.86.50) vs. 21.60 (0.00, 52.50), P = 0.008), and proximal extent (19.00 (5.04, 24.00) vs. 5.50 (2.56, 11.13), P = 0.011) were markedly higher in responders than nonresponders. Proximal MNBI (OR = 0.997, P = 0.042, and optimal cutoff = 2140 Ω) and weakly acid reflux (OR = 1.051, P = 0.029, and optimal cutoff = 45) were independent predictors of standard antireflux therapy efficacy. The combination predictive value did not show better results than either individual predictor. Proximal MNBI < 2140 Ω may be used to screen patients with nonacid GERC suitable for standard antireflux therapy and in standardized management algorithms for nonacid GERC. In the absence of MNBI, weakly acid reflux > 45 can be used as an auxiliary indicator.

Assessment of Esophageal Motility Disorders in Patients With Refractory Gastroesophageal Reflux Disease

There is insufficient data about esophageal body dysmotility in patients with refractory gastroesophageal reflux disease (RGERD) and inadequate response to proton pump inhibitors (PPIs) treatment. This study aimed to assess esophageal motility disorder and reflux parameters among these patients by high-resolution manometry (HRM) and intraluminal impedance and pH (MII‐pH) monitoring after stopping PPI therapy. A retrospective study was conducted among 100 RGERD patients admitted to Taleghani Hospital (Tehran, Iran) for one year. More than half of them were males (55%). Their mean age was 47.10±6.92, and 50% of patients had ineffective esophageal motility (IEM). Middle, distal, and proximal esophageal pressure (MEP, DEP, and PEP), lower esophageal sphincter (LES) basal pressure (LESP), integrated relaxation pressure (IRP), distal contractile integral (DCI), large breaks, upper esophageal sphincter basal pressure (UESP), and LES length (LESL) in IEM patients were significantly lower than the patients with normal esophageal motility (P&lt;0.001). Furthermore, there were more patients in the IEM group with long-term and abnormal weakly acid reflux compared with the non-IEM group (P&lt;0.05). It seems that the evaluation of reflux parameters and esophageal motility could lead to additional insights into the pathophysiological mechanisms of RGERD. Nevertheless, further studies are suggested to evaluate the effects of esophageal motility disorders among RGERD patients.

Analysis of Esophageal Motility and Reflux Characteristics in Patients with Gastroesophageal Reflux Disease With or Without Extraesophageal Symptoms.

The pathogenesis of extraesophageal symptoms of gastroesophageal reflux disease is complex, and esophageal motility and reflux may be involved in it. In this study, we aimed to compare esophageal motility and reflux characteristics in gastroesopha- geal reflux disease patients with and without extraesophageal symptoms by high-resolution manometry and multichannel intraluminal impedance-pH monitoring. We retrospectively studied gastroesophageal reflux disease patients between January 2014 and December 2018. All patients had undergone high-resolution manometry and multichannel intraluminal impedance-pH monitoring. The results were compared and analyzed. A total of 59 patients were included in this study. Patients were divided into 3 groups according to their main complaint: only typical symptoms (group A, n = 11), both typical and extraesophageal symptoms (group B, n = 33), and only extraesophageal symp- toms (group C, n = 15). Compared with group A, the lower esophageal sphincter basal pressure, integrated residual pressure, and lower esophageal sphincter length were lower, and the proximal reflux percentages of a weak acid and non-acid reflux were higher in group B and group C (P < .017). The positive rate of esophageal motility disorders was lower in group A than in other groups (P < .05). The propor- tion of patients with multiple rapid swallows/single swallow-distal contractile integral ratio greater than 1-was higher in group A than in other groups (P < .05). Decreased lower esophageal sphincter pressure and lower esophageal sphincter length, increased proximal esophageal reflux of weak acid and non-acid reflux, esophageal motility disorders, and decreased peristaltic reserve are involved in the pathogenesis of extraesophageal symptoms of gastroesophageal reflux disease.

Effect of Continuous Positive Airway Pressure on Chronic Cough in Patients with Obstructive Sleep Apnea and Concomitant Gastroesophageal Reflux.

BackgroundObstructive sleep apnea (OSA) and/or gastroesophageal reflux (GER) may be the contributors to chronic cough in patients with OSA and concomitant GER. This study aimed to explore whether continuous positive airway pressure (CPAP), antireflux treatment and lifestyle modifications improve chronic cough in patients with OSA and concomitant GER.MethodsPatients with OSA and concomitant GER who also experienced chronic cough were enrolled, and were divided into two groups. Patients who were treated with general treatment (antireflux treatment and lifestyle modifications) as the control group, and patients who were treated with CPAP and general treatment as the treatment group. Effects of different treatments on chronic cough were assessed, and the association among chronic cough, GER and OSA was evaluated by Pearson’s correlation analysis.ResultsThe Pittsburgh Sleep Quality Index and Epworth Sleepiness Scale were better in the treatment group after 1 week of treatment; further, the improvement became stronger with the duration of therapy. The gastroesophageal reflux disease questionnaire, visual analog scale (VAS) for cough, and daytime and nighttime cough symptom scores significantly improved in both groups after treatment, whereas this improvement was more significant in the treatment group. Significant associations between the apnea-hypopnea index (AHI) and VAS, weak acid reflux and VAS, and weak acid reflux and AHI were observed.ConclusionCPAP improved the symptoms of chronic cough and GER in patients with OSA and concomitant GER. AHI and weak acid reflux may be important factors affecting the therapeutic effect of chronic cough in patients with OSA and concomitant GER.

Impact of Acid, Weakly Acid and Alkaline Laryngopharyngeal Reflux on Voice Quality

To analyze pre to posttreatment voice changes regarding the type of reflux in patients with acid, weakly acid or alkaline laryngopharyngeal reflux (LPR). Patients with LPR, diagnosed using hypopharyngeal-esophageal multichannel intraluminal impedance pH-monitoring (HEMII-pH), were prospectively recruited from three University Hospitals. Patients were treated with a combination of diet, proton pump inhibitors, magaldrate and alginate for 3 months. The following clinical and voice quality outcomes were studied pre to posttreatment according to the type of reflux (acid, weakly acid, nonacid): HEMII-pH, gastrointestinal endoscopy features, reflux symptom score (RSS), reflux sign assessment (RSA), voice handicap index (VHI), perceptual voice assessment (grade of dysphonia and roughness), aerodynamic and acoustic measurements. From December 2018 to March 2021, 160 patients completed the evaluations, accounting for 60 acid, 52 weakly acid, and 48 alkaline cases of LPR. There were no baseline differences in clinical and voice quality outcomes between groups. RSS and RSA significantly improved from pre to posttreatment in the entire cohort and in all patient groups. VHI, dysphonia and roughness, maximum phonation time, Jitter, Shimmer and noise to harmonic ratio significantly improved from pre to posttreatment. Individuals with alkaline reflux reported better voice quality improvements as compared to acid and weakly acid reflux patients. Patients with acid and alkaline reflux reported better posttreatment voice quality outcomes as compared to weakly acid reflux patients. Future basic science and clinical studies are needed to better understand the histological changes of the vocal folds due to reflux of varying pH types and gastroduodenal enzyme content.

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

BackgroundMagnetic sphincter augmentation (MSA) is a modern surgical anti-reflux technique with proven efficacy and low postoperative morbidity in patients with acidic reflux. The aim of this retrospective review study was to evaluate the symptomatic outcome of MSA in patients with weakly acidic reflux. MethodsFrom a prospectively collected clinical database, comprising all 327 patients that underwent MSA at our institution, a total of 67 patients with preoperative weakly acidic reflux measured in the 24-h impedance-pH-metry were identified. Postoperative gastrointestinal symptoms, proton pump inhibitor intake (PPI), GERD Health-Related Quality-of-Life (GERD-HRQL), alimentary satisfaction (AS), and patients’ overall satisfaction were evaluated within highly standardized follow-up appointments. Furthermore, outcome of these patients was compared to the postoperative outcome of a comparable group of patients with a preoperative acidic reflux. ResultsAt a median follow-up of 24 months, none of the patients with weakly acidic reflux presented with persistent dysphagia, or underwent endoscopic dilatation or reoperation. The postoperative GERD-HRQL score was significantly reduced (2 vs. 20; p = 0.001) and the median AS was 9/10. Preoperative daily heartburn, regurgitations, and respiratory complaints were improved in 95%, 95%, and 96% of patients, respectively. A total of 10% of the patients continued to use PPIs postoperatively. No significant difference was observed in terms of postoperative outcome or quality of life when comparing weakly acidic reflux patients with those diagnosed with preoperative acidic reflux. ConclusionMagnetic sphincter augmentation significantly improves GERD-related symptoms and quality of life in patients with weakly acidic reflux with very low postoperative morbidity.

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

Background/Aims: The incidence of reflux esophagitis (RE) has a striking predominance in males. Conversely, non-erosive reflux disease (NERD) is more common in females. This imbalance of gastroesophageal reflux disease (GERD) implies sex-related differences in its pathogenesis. However, limited studies have analyzed the sex-based differences in pH parameters and esophageal impedance of GERD patients.Methods: This study evaluated sex-based pathogenesis differences by comparing reflux episodes, mean nocturnal baseline impedance (MNBI) values, and post-reflux swallow-induced peristaltic wave (PSPW) index values of males with GERD and females with GERD using 24-h multichannel intraluminal impedance and pH monitoring.Results: We analyzed 181 patients (102 males and 79 females) with GERD. Reflux symptom index (RSI) scores were higher in females than that in males (P < 0.05). Males had significantly longer acid exposure times, higher DeMeester scores, and more acid reflux episodes than females (P < 0.05). Females had more instances of weakly acidic reflux than males (P < 0.01). The PSPW index values of males and females were similar (P > 0.05). Compared with females, males had lower MNBI values for the mid and distal esophagus (P < 0.05). However, with increasing age, the MNBI values of females decreased more rapidly than those of males. MNBI values of elderly patients of both sexes older than 60 years were similar.Conclusions: Acid reflux is more likely to occur in males; however, females tend to have more instances of weakly acid reflux. The integrity of the esophageal mucosa is more fragile in males than in females; however, the esophageal mucosal barrier attenuates more rapidly with increasing age in females than in males.

Association Between Laryngopharyngeal Reflux and Media Otitis: A Systematic Review.

To investigate the relationship between laryngopharyngeal reflux (LPR) and recurrent (ROM) or chronic otitis media with effusion (COME). PubMed, Scopus, and Cochrane Library. Three authors searched articles published between January 1980 and September 2020 about the association between LPR and the development of recurrent or chronic otitis media. Inclusion, exclusion, diagnostic criteria, and clinical outcome evaluation of included studies were analyzed using PRISMA criteria. The bias analysis of included studies was evaluated with the Tool to assess Risk of Bias of the CLARITY group. Twenty-six clinical and three experimental articles met our inclusion criteria, accounting for 1,624 children and 144 adults with COME or ROM. According to the pH study type, the prevalence of LPR and gastroesophageal reflux disease (GERD) in OM patients were 28.7% (range, 8-100%) and 40.7 (range, 18-64%), respectively. The majority of studies identified pepsin or pepsinogen in middle ear effusion, with a range of mean concentrations depending on the technique used to measure pepsin. There was an important heterogeneity between studies regarding definition of COME, ROM, and LPR, exclusion criteria, methods used to measure pepsin/pepsinogen in middle ear secretions and outcome assessments. The association between LPR and OM is still unclear. Future clinical and experimental studies are needed to investigate the association between LPR and OM in both children and adults through extensive gastric content analysis in middle ear suppurations and impedance-pH monitoring considering acid, weakly acid, and alkaline reflux events.

Laryngopharyngeal Reflux: A State-of-the-Art Algorithm Management for Primary Care Physicians.

Laryngopharyngeal reflux (LPR) is a common disease in the general population with acute or chronic symptoms. LPR is often misdiagnosed in primary care because of the lack of typical gastroesophageal reflux disease (GERD) symptoms and findings on endoscopy. Depending on the physician’s specialty and experience, LPR may be over- or under-diagnosed. Management of LPR is potentially entirely feasible in primary care as long as General Practitioners (GPs) are aware of certain “red flags” that will prompt referral to a Gastroenterologist or an Otolaryngologist. The use of patient-reported outcome questionnaires and the consideration of some easy ways to diagnose LPR without special instrumentation oropharyngeal findings may help the GP to diagnose and often manage LPR. In this review, we provide a practical algorithm for LPR management for GPs and other specialists that cannot perform fiberoptic examination. In this algorithm, physicians have to exclude some confounding conditions such as allergy or other causes of pharyngolaryngitis and “red flags”. They may prescribe an empirical treatment based on diet and behavioral changes with or without medication, depending on the symptom severity. Proton pump inhibitors and alginates remain a popular choice in order to protect the upper aerodigestive tract mucosa from acid, weakly acid and alkaline pharyngeal reflux events.

Esophageal pH-impedance monitoring of reflux patterns in non-erosive reflux disease, reflux hypersensitivity and functional heartburn

To analyze the differences in reflux patterns in 24-hour esophageal pH-impedance monitoring in patients with non-erosive reflux disease (NERD), reflux hypersensitivity (RH) and functional heartburn (FH) and explore the possible mechanism of symptoms in patients with heartburn and negative endoscopic findings. Seventy-nine patients with heartburn as the main symptoms but negative endoscopic findings, including 35 with NERD, 16 with RH and 28 with FH, were enrolled in this study.All the patients underwent 24-h esophageal pH-impedance monitoring and esophagogastroscopy, and the results were compared among the 3 groups. Acid reflux episode was significantly increased and weakly alkaline reflux episode was significantly decreased in NERD group in comparison with RH group and FH group (P < 0.05).The patients in NERD group showed significantly increased total reflux episode, mixed reflux episode, proximal acid reflux episode, proximal weak acid reflux episode, total proximal reflux episode, percentage of proximal acid reflux, percentage of proximal weak acid reflux, and percentage of total proximal reflux as compared with the other two groups (all P < 0.05).Bolus clear time was significantly prolonged in NERD group compared with that in the other two groups (P < 0.05).Analysis of the reflux acidity showed that the percentages of different reflux episodes differed significantly among the 3 groups (P < 0.05);acid reflux was the main reflux in NERD, while weak acid reflux was the main reflux in RH and FH groups, which had also significantly increased weakly alkaline reflux episodes compared with NERD group. Patients with NERD, RH and FH had different reflux patterns.Acid reflux is predominant in the NERD, while weakly alkaline reflux is significantly increased RH and FH.In patients with normal esophageal acid exposure but without symptoms or without recorded symptoms during esophageal pH-impedance monitoring, analysis of the total reflux episode, mixed reflux episode, proximal acid reflux episode and percentage can help in the differential diagnosis between RH and FH.

High-resolution impedance manometry and 24-hour multichannel intraluminal impedance with pH testing before and after sleeve gastrectomy: de novo reflux in a prospective series.

Laparoscopic sleeve gastrectomy (SG) is increasingly popular but concern regarding its effect on gastroesophageal reflux disease remain. The current literature is conflicting, and there have been little objective data. To objectively and more accurately assess the impact of SG on esophago-gastric physiology. Centre of Excellence in Metabolic and Bariatric Surgery, Private Hospital, Australia. Prospective cohort study of 31 patients undergoing SG with high-resolution impedance manometry (HRM), 24-hour multichannel intraluminal impedance combined with pH testing (MII-pH), and Gastroesophageal Reflux Disease Symptom Assessment Scale (GSAS) questionnaire 1 month before and 6 months after SG. There were 31 patients that underwent SG, 20 with synchronous hiatal repair and fixation, and 6 that were excluded. HRM demonstrated significantly increased intragastric pressures (15.5-29.6 mm Hg) and failed swallows (3.1-7.5%) but no other change in esophageal motility. MII-pH did not demonstrate significant changes in acid exposure time (8.5%-7.5%) or number of reflux episodes, although the numbers of long reflux episodes (2.3-4.7) and weak acid reflux episodes were significantly increased (15.4-55.2). DeMeester and GSAS scores were not significantly changed. There was no significant difference in patients with preexisting reflux. However, for patients without preexisting reflux, acid exposure time increased significantly (1.3%-6.7%), as did DeMeester scores (5.8-24.5) and the numbers of long reflux episodes (.1-4.4) and weakly acidic episodes (22.1-89.2). SG was associated with increased intragastric pressures, without changes in esophageal motility or acid exposure. For patients without preexisting reflux, there were increases in acid exposure time, long reflux episodes, weakly acidic reflux episodes, and DeMeester score.

Etiological involvement of weak acid reflux in the development of esophageal carcinoma.

435 Background: Patients with gastroesophageal reflux disease (GERD) with mixed gastric acid–bile acid reflux are at a high risk of developing reflux-induced esophageal cancer. Increased local production of prostaglandin E2 (PGE2) is etiologically associated with reflux-induced esophageal cancer pathogenesis; however, the underlying mechanism remains unclear. Our aim was to investigate the relationship between PGE2 production in esophageal cells and reflux fluids, particularly gastric acid. The effect of the Kampo medicine Hangeshashinto (HST), which reduced the incidence of reflux-induced esophageal cancer in rats (Surgery 2018), on PGE2 production was also examined. Methods: Esophageal squamous cell carcinoma were treated for 2 h with acidic culture condition (pH 3.5 – 6.5) and chenodeoxycholic acid (CDCA; 200, 400 μmol/L), followed by measurement of PGE2 production in the culture medium for the additional 6 h by enzyme-linked immunosorbent assay. Results: CDCA induced PGE2 production and significantly increased cyclooxygenase-2 (cox-2) expression. However, in weak acidic conditions (pH 4–5), a pH-specific and significant increase in PGE2 production with no increase in cox-2 expression was observed. cPLA2 inhibitor decreased the effect of weak acid stimulation, indicating that the mechanism underlying PGE2 production differs between weak acid and CDCA. In addition, HST significantly inhibited both weak acid- and CDCA-induced PGE2 production. Conclusions: The synergistic effect of bile acid-induced cox-2 expression and weak acid-induced arachidonic acid production via cPLA2 can cause excessive PGE2 production. Therefore, mixed reflux showing pH 4–5 could contribute to the high incidence of esophageal cancer, which might be prevented by HST treatment. Weak acid reflux around pH 4–5 has been observed in PPI-treated patients, who could exhibit excessive PGE2 production as well as increased risk of reflux-induced esophageal cancer.

Capillary electrophoretic analysis of ionic content in exhaled breath condensate and pH monitoring as a non-invasive method in gastroesophageal reflux disease diagnostics

In this study, the ionic profile and pH of exhaled breath condensate (EBC) in a group of patients with acid and weakly acid reflux and no-reflux controls were compared. A portable sampler was used for non-invasive EBC collection from five exhalations. The ionic profile (anions, cations, organic acids) and pH of the collected EBC samples were measured by capillary electrophoresis with contactless conductivity detection and a pH microelectrode, respectively. Several ions were elevated in the patient groups. Sodium cation was elevated in weakly acid reflux (significance level p < 0.01) and acid reflux (p < 0.05) compared to no-reflux controls. Butyrate and propionate were elevated in both acid reflux and weakly acid reflux compared to no-reflux controls (butyrate: p < 0.01, propionate: p < 0.05). The median values of pH (after de-aeration with N2) were also significantly higher (p < 0.01) in groups with acid reflux and weakly acid reflux than in the control group with no reflux. The ionic analysis and simultaneous pH measurement offer a simple, cheap, fast, and non-invasive approach in gastroesophageal reflux disease diagnostics.