Multichannel Intraluminal impedance-pH Research Articles

Association between laryngopharyngeal reflux clinical scores and esophageal multichannel intraluminal impedance pH monitoring interpretation according to Lyon Consensus 2.0.

Laryngopharyngeal reflux remains a diagnostic challenge due to the lack of a definitive diagnostic tool. Esophageal multichannel intraluminal impedance (MII) pH monitoring has been proven reliable for detecting gastric reflux. This study aims to evaluate the association between clinical scores and MII/pH monitoring according to the Lyon Consensus 2.0. Patients with laryngo-pharyngeal symptoms (LPS) who had a reflux symptom index (RSI) ≥13 or reflux finding score (RFS) ≥7 underwent MII/pH monitoring. The findings were analyzed in comparison with clinical scores. A total of 100 patients meeting the inclusion criteria were recruited for this study. MII/pH monitoring revealed a median acid exposure time (AET) of 1.9% (interquartile range [IQR] = 0.2, 4.9), with 22% of patients recording an AET above 6%. The median number of reflux episodes was 29.5 episodes per day (IQR = 19.0, 43.8), with 7% experiencing more than 80 episodes per day. Gas reflux was identified as the most prevalent type. Based on the Lyon Consensus 2.0, 25 patients exhibited conclusive pathological reflux, while 75 patients showed no conclusive evidence of pathological reflux. No significant differences were found in RSI and RFS between these groups. Only gas reflux episodes showed a significant correlation with RSI (r = 0.255, P = 0.011). RSI and RFS among patients with LPS showed no statistically significant differences in identifying pathological reflux or no conclusive evidence of pathological reflux. This finding suggests that the pathophysiology underlying LPS may not be solely attributable to reflux.

Transoral Incisionless Fundoplication Leads to Esophageal Mucosa Healing in Responder Patients Followed up to 2 Years, as Documented by Esophageal Mean Nocturnal Baseline Impedance.

Decrease of esophageal mean nocturnal baseline impedance reflects loss of mucosal integrity. It can predict response to anti-reflux therapy. Mean nocturnal baseline impedance after transoral incisionless fundoplication for gastroesophageal reflux disease has never been assessed. The aim of the study is to investigate mean nocturnal baseline impedance and conventional pathophysiological parameters following transoral incisionless fundoplication. Patients prospectively treated by transoral incisionless fundoplication in a single center were retrospectively reviewed regarding 1- and 2-year 24-hour pH-metry and multichannel intraluminal impedance with calculation of mean nocturnal baseline impedance, gastroesophageal reflux disease-health related quality of life and reflux symptom index scores. Thirty-eight and 17/38 patients with 1- and 2-year 24-hour pH-multichannel intraluminal impedance assessment and mean nocturnal baseline impedance's calculation after transoral incisionless fundoplication, respectively, were identified. Mean nocturnal baseline impedance significantly increased up to 2-year follow-up (P = 0.033), along with significant decrease in % of acid exposure time (P = 0.003), gastroesophageal reflux disease-health related quality of life score (P < 0.001), and reflux symptom index (P = 0.008), compared with baseline. The longest orthostatic reflux decreased too, approaching statistical significance (P = 0.054). These significant changes occurred in patients experiencing ≥ 50% reduction of symptom questionnaires' scores ("responders"). Conversely, mean nocturnal baseline impedance worsened and no significant changes of 24-hour pH-multichannel intraluminal impedance metrics were observed in "non-responder" patients (symptom questionnaires' scores decrease < 50%).ConclusionIn patients who responded a significant improvement of mean nocturnal baseline impedance and % acid exposure time was observed up to 2-year follow-up, suggesting that transoral incisionless fundoplication achieves an effective esophageal mucosa healing besides symptom improvement.

Association Between Height and Laryngopharyngeal Reflux: Analysis Using the 24-Hour Hypopharyngeal-Esophageal Multichannel Intraluminal Impedance-pH Monitoring

ObjectiveHeight has the strongest correlation with esophageal length among the external anthropometric indices. Based on the association between laryngopharyngeal reflux (LPR) and the upper esophageal sphincter, this study aimed to investigate the relationship between height and LPR. MethodsRetrospective chart analysis of patients who visited an outpatient clinic with symptoms of LPR and underwent a 24-hour hypopharyngeal-esophageal multichannel intraluminal impedance-pH (24-hr HEMII-pH) monitoring. The study analyzed the relationship between height and LPR by 1) in total of 219 patients 2) in males and females; and 3) in patients under age 60 and over age 60. ResultsThe relationship between height and LPR was analyzed for a total of 219 patients. There was no statistical significance between the number of pharyngeal reflux episodes and the height of subjects. When same analysis was done according to gender, the number of pharyngeal reflux episodes decreased as height increased in males, which was statistically significant, but not in females. Further analysis was done according to age in male and female respectively. In male under age 60, there was statistical significance between the number of pharyngeal reflux episodes and the height of subjects, but not in over age 60. Also, in female under age 60 and over age 60, there was no statistical significance between the number of Pharyngeal reflux episodes and the height of subjects. ConclusionsThis study suggests a correlation between height and pharyngeal reflux events in males and individuals under 60 years old tested with the 24-hr HEMII-pH monitoring.

Evaluation of Gastroesophageal Reflux in Symptomatic Young Infants Using Multichannel Intraluminal pH-Impedance Testing: A large Cohort Study from a Single Center.

This study aimed to assess the use of combined multichannel intraluminal impedance and pH studies (MII-pH) in a large group of symptomatic young infants, to characterize the occurrence of gastroesophageal reflux disease (GERD), and to establish temporal association of the reflux behaviors with gastroesophageal reflux using symptom indices. This is a retrospective cohort study on 181 infants who underwent MII-pH studies for clinical behaviors that were suggestive of GERD. Symptom index (SI) and symptom association probability (SAP) were used to establish symptom association with reflux. More than 100 GER episodes in 24 hours or acid reflux index > 10% was considered pathological reflux. A total of 181 infants (median age: 60 days, interquartile range [IQR]: 34-108) underwent MII-pH studies with median study duration of 22.41 hours (IQR: 21.5-23.32). A total of 4,070 hours of data were analyzed, with 8,480 reflux events (2,996 [35%] acidic, 5,484 [65%] nonacidic). A total of 2,541 symptoms were noted, 894 (35%) were temporally related to reflux events. A total of 113 infants (62.4%) had positive symptom association with SI > 50% and/or SAP > 95% for at least one symptom. There was modest symptom association for choking and gagging, but apnea, bradycardia, and desaturations had poor symptom association. Only 29 infants (16%) had pathological reflux, and only 18 infants (10%) had both pathological reflux and positive symptom association. MII-pH can be used to characterize GERD in young infants, along with establishing temporal association with symptoms. Pathological reflux in symptomatic young infants is not common, but symptom association may occur without frequent or acidic reflux. · Gastroesophageal reflux (GER) disease can be studied in young infants using MII-pH, to characterize the frequency and nature of GER events.. · The probability of GER events being associated temporally with GER symptoms can also be determined using MII-pH in this population.. · Using frequency of GER events, reflux indices, and symptom association indices with MII-pH, infants having true GER disease can be identified, thereby reducing unnecessary therapy.. · Symptom association may occur even without frequent or severe acidic reflux..

363. REFLUX MICRO-ASPIRATION: WHAT HAVE WE LEARNED

Abstract Background The accurate diagnosis of gastro-oesophageal reflux pulmonary microaspiration has only become possible recently with the introduction of a novel technique of reflux micro-aspiration scintigraphy study combined with single photon emission computed tomography (SPECT) combined with x-ray tomography (CT) in a hybrid instrument. This has allowed the accurate diagnosis of pulmonary and airway contamination with refluxate. Previously only patients with large volume symptomatic reflux aspiration were diagnosed clinically (Mendelson syndrome) or by 2-dimentional barium meal or an older plantar (2 dimensional) technique of scintigraphic aspiration studies. The concept of reflux micro-aspiration has been implicated in multiple pulmonary diseases but without absolute proof from an adequate diagnostic test. Little was known about the natural history, physiology, and response to treatment amongst patients with silent reflux micro-aspiration. The aim of this presentation is to summarise a series of research projects studying the natural history of the disease, common presenting symptoms, pathophysiology and response to treatment. Methods A prospectively populated database of patients referred to a tertiary specialist reflux diagnostic service with atypical and/or treatment resistant reflux was evaluated. The database contained records of consecutive patients including demographic information, presenting symptoms, investigations including imaging, upper gastro-intestinal physiology studies and novel reflux micro-aspiration scintigraphy studies. Treatment details including medical and surgical treatment and post treatment clinical information and investigations. Multiple studies were conducted using the information from the database and findings are summarised in this presentation. Results The novel reflux micro-aspiration scintigraphy with SPECT/CT was compared with other studies (multichannel intraluminal impedance and 24-hour pH monitoring) and was found to be sensitive to reflux occurring outside the oesophagus. Patients with reflux micro-aspiration can present a wide variety of symptoms, commonly a combination of typical symptoms of gastro-oesophageal reflux disease (heartburn and regurgitation) and respiratory symptoms. Reflux micro-aspiration was associated with reduced lower oesophageal sphincter pressure, severe ineffective oesophageal motility (IOM), and pharyngeal contamination with refluxate on reflux scintigraphy. Delayed liquid gastric emptying was not associated with reflux micro-aspiration, however gastroparesis with solids is associated with micro-aspiration. Micro-aspiration was common in patients with giant hiatus hernias and mostly resolved with surgery. Anti-reflux surgery resulted in resolution of aspiration in the majority of patients, however severe IOM was associated with lesser rates of microaspiration resolution. Conclusion Reflux micro-aspiration appears to be a more common manifestation of GORD than previously thought. The work summarised in this presentation discusses the presentation, physiological associations, and treatment of patients with reflux micro-aspiration.

Comparison of Esophageal Dysmotility and Reflux Burden in Patients with Different Metabolic Obesity Phenotypes Based on High-Resolution Impedance Manometry and 24-h Impedance-pH

Introduction: The relationship between the metabolically healthy obesity (MHO) phenotype and the occurrence of gastroesophageal reflux disease (GERD) and inefficient esophageal motility (IEM) is still unclear. Thus, we assessed the association between different metabolic obesity phenotypes and GERD and IEM using empirical data. Methods: We collected clinical and test data of 712 patients, including 24-h multichannel intraluminal impedance-pH (24-h MII-pH) monitoring, high-resolution manometry (HRM), and endoscopy. We divided 567 individuals into four categories according to their metabolic obesity phenotype: metabolically unhealthy non-obesity (MUNO), metabolically unhealthy obesity (MUO), metabolically healthy non-obesity (MHNO), and MHO. We compared differences in the 24-h MII-pH monitoring, HRM, and endoscopy findings among the four metabolic obesity phenotypes. Results: Patients with the MUNO, MHO, or MUO phenotype showed a greater risk of IEM and GERD (pathologic acid exposure time [AET] >6%) compared with patients with the MHNO phenotype. Regarding the HRM results, patients with the MHNO or MUNO phenotype had a lower integrated relaxation pressure, esophageal sphincter pressure, and esophagogastric junction contractile integral, and more ineffective swallows than patients with the MHO or MUO phenotype (p < 0.05). In terms of 24-h MII-pH, patients with the MHO or MUO phenotype had a higher total, upright, and supine AET; a higher total number of reflux episodes (TRs); and a lower mean nocturnal baseline impedance and post-reflux swallow-induced peristaltic wave index compared with those with the MHNO or MUNO phenotype (all p < 0.05). Considering the odds ratio of 19.086 (95% confidence interval 6.170–59.044) for pathologic AET and 3.659 (95% confidence interval 1.647–8.130) for IEM, patients with the MUO phenotype had the greatest risk after adjusting for all confounding variables. Conclusion: Obesity and metabolic disorders increase the risk of GERD and IEM. Obesity has a greater impact on esophageal dysmotility and pathologic acid exposure than metabolic diseases.

Comparison between Conventional and Simple Measuring Methods of Mean Nocturnal Baseline Impedance in Pediatric Gastroesophageal Reflux Disease.

(1) Background: Multichannel intraluminal impedance-pH (MII-pH) monitoring is commonly used to diagnose gastroesophageal reflux disease (GERD). The mean nocturnal baseline impedance (MNBI) is an important parameter, reflecting the esophageal mucosal integrity and improvement in GERD. This study aims to evaluate the correlation between conventionally measured MNBI and a recently described simple MNBI measurement method in diagnosing pediatric GERD. (2) Methods: This prospective observational study enrolled 64 children aged one month to 18 years who underwent 24 h MII-pH monitoring. Conventional MNBI was measured during stable 10 min intervals at night, while the simple MNBI method averaged impedance throughout the nocturnal supine period. (3) Results: Strong correlations were found between conventional and simple MNBI values across all impedance channels in both infants (r > 0.85) and older children (r > 0.9). Conventional and simple MNBIs in the most distal channel (Z6) effectively differentiated non-erosive reflux disease (NERD) from other phenotypes, with AUCs of 0.864 and 0.860, respectively. The simple MNBI demonstrated good diagnostic performance with similar sensitivity and specificity to the conventional MNBI. (4) Conclusions: Including MNBI measurements into routine MII-pH monitoring may enhance GERD diagnosis and reduce the need for more invasive procedures.

The impact of gastroesophageal reflux disease on upper esophageal sphincter function: Insights from PH impedance and high-resolution manometry.

Lower esophageal sphincter (LES) pathophysiology has been established in gastroesophageal reflux disease (GERD); however, less is understood regarding the role the upper esophageal sphincter (UES) plays in preventing laryngopharynphageal reflux. Sustained UES basal pressure prevents reflux into the pharynx while allowing relaxation during ingestion. We investigate whether GERD influences UES function via HRM and pH Impedance testing. A retrospective analysis of 318 patients who underwent high-resolution manometry with trans-nasally placed manometric catheter and 24-h multichannel intraluminal impedance pH monitoring. One hundred and forty-seven patients met Lyon consensus criteria for GERD based on acid exposure time >6%. The most common chief concern was heartburn or reflux, present in 59% of these patients. Upper esophageal sphincter basal and residual pressures were not significantly different between patients with GERD when compared to those without GERD, including a subanalysis of patients with extraesophageal symptoms. The LES basal and residual pressures, DCI and MNBI are statistically lower in patients with pathologic GERD. HRM and pH Impedance testing demonstrates no difference in UES basal and residual pressures based on pH diagnosis of GERD. We redemonstrate the association with hypotonic LES, diminished DCI and MNBI with GERD.

Esophageal Baseline Impedance is Associated with Laryngopharyngeal Reflux and Treatment Response.

To evaluate the efficacy of distal esophageal mean nocturnal baseline impedance (MNBI), a general marker of esophageal mucosal barrier integrity, in predicting laryngopharyngeal reflux (LPR) and symptomatic response to acid reflux therapy. This retrospective study analyzed 173 patients who presented with symptoms of laryngopharyngeal reflux and underwent 24-h multichannel intraluminal impedance-pH (MII-pH) testing. Mean nocturnal baseline impedance values were calculated and assessed for their association and ability to predict LPR symptoms, MII-pH results, treatment response, and other markers of LPR. Notably, 153 of the 173 patients were tested off acid suppression medication and included in statistical analysis. Based on the MII-pH probe data, 108 (71%) patients had LPR, 8 (5%) had gastroesophageal reflux disease (GERD), and 37 (24%) were without pathologic reflux. Distal esophageal MNBI of LPR patients was significantly lower in LPR patients than patients with negative studies (1332 ± 94.8 vs. 2158 ± 173.5, p = 0.001). Among 118 patients who trialed antireflux therapy, a distal esophageal MNBI cutoff value of <1580 Ω was an independent predictor of treatment response (OR = 4.148 [1.877-9.189]). This value better predicted improvement with antireflux therapy for LPR than other objective MII-pH probe data, which were not independent predictors of treatment response. Distal esophageal MNBI values may have value in the diagnosis of LPR and potentially predict medication responsiveness in LPR patients. 3 Laryngoscope, 134:4071-4077, 2024.

A prediction model of abnormal acid reflux in gastroesophageal reflux disease.

The measurement of esophageal acid exposure time (AET) using combined multichannel intraluminal impedance-pH (MII-pH) tests is the gold standard for diagnosing gastroesophageal reflux disease (GERD). However, this catheter-based 24-h test can cause considerable patient discomfort. Our aim is to identify factors affecting AET and to develop a scoring model for predicting AET abnormalities before conducting the MII-pH test. Of the 366 patients who underwent MII-pH test at two facilities in Japan and Vietnam, 255 patients who also had esophagogastroduodenoscopy and high-resolution manometry were included in this study. Logistic regression analysis was conducted using risk factors for AET>6% identified from a derivation cohort (n=109). A scoring system predicting AET>6% was then constructed and externally validated with a separate cohort (n=146). Three variables were derived from the prediction model: male gender, Hill grades III-IV, and weak mean distal contractile integrals. Based on these scores, patients were classified into low (0 point), intermediate (1-3 points), and high (4 points) risk groups. The probabilities of having an AET>6% were 6%, 34%, and 100% for these groups, respectively. A score of <1 excluded patients with abnormal AET, with a negative predictive value of 93.8% in the derivation cohort and 80.0% in the validation cohort. We derived and externally validated a prediction model for abnormal AET. This system could assist in guiding the appropriate treatment strategies for GERD.

Differences Between Patients with Heartburn Refractory to Vonoprazan and Those Refractory to Proton Pump Inhibitors

BackgroundVonoprazan, a potassium-competitive acid blocker, demonstrates more potent acid inhibition than proton pump inhibitors (PPIs). This study aimed to evaluate the effect of vonoprazan in patients with unproven gastroesophageal reflux disease (GERD) by comparing patients with vonoprazan-refractory heartburn with those with PPI-refractory heartburn.MethodsThis study included 104 consecutive patients with vonoprazan- or PPI-refractory heartburn (52 patients each), no erosive esophagitis on endoscopy and who underwent combined multichannel intraluminal impedance–pH (MII–pH) testing with vonoprazan/PPI discontinuation. Patients’ backgrounds, symptom scores from four questionnaires, MII–pH results and high-resolution manometry results were compared between the two groups.ResultsThe vonoprazan group demonstrated significantly higher GERD symptoms and scores of abdominal pain and diarrhea on the Gastrointestinal Symptom Rating Scale questionnaire. MII–pH results revealed that the vonoprazan group demonstrated 40.4%, 17.3%, and 42.3% and the PPIs group exhibited 26.9%, 17.3%, and 55.8% of abnormal acid reflux [true non-erosive reflux disease (NERD)], reflux hypersensitivity and functional heartburn, respectively. The vonoprazan group demonstrated higher true NERD rates but with no significant difference (p = 0.307). Among the vonoprazan group, eight patients with true NERD underwent another MII–pH test on vonoprazan, and all cases demonstrated normal acid exposure times (0.0% [0.0–0.3]).ConclusionPatients with unproven GERD with vonoprazan-refractory heartburn demonstrated more symptoms, including not only GERD symptoms but also functional dyspepsia and irritable bowel syndrome symptoms, than those with PPI-refractory heartburn.

Narrative review of relationship between chronic cough and laryngopharyngeal reflux.

Gastroesophageal reflux disease (GERD) as a possible cause of chronic cough is known for decades. However, more than 75% of patients with extraoesophageal symptoms do not suffer from typical symptoms of GERD like pyrosis and regurgitations and have negative upper gastrointestinal endoscopy. For such a condition term laryngopharyngeal reflux (LPR) was introduced and is used for more than two decades. Since the comprehensive information on relationship between chronic cough and LPR is missing the aim of this paper is to summarize current knowledge based on review of published information during last 13 years. Laryngopharyngeal reflux is found in 20% of patients with chronic cough. The main and recognized diagnostic method for LPR is 24-h multichannel intraluminal impedance-pH (MII-pH) monitoring, revealing reflux episodes irritating the upper and lower respiratory tract mucosa. The treatment of LPR should be initiated with dietary and lifestyle measures, followed by proton pump inhibitor (PPI) therapy and other measures. Despite progress, more research is needed for accurate diagnosis and targeted therapies. Key areas for exploration include biomarkers for diagnosis, the impact of non-acid reflux on symptom development, and the efficacy of new drugs. Further studies with a focused population, excluding other causes like asthma, and using new diagnostic criteria for LPR are essential. It's crucial to consider LPR as a potential cause of unexplained chronic cough and to approach diagnosis and treatment with a multidisciplinary perspective.

The Time-Point Distribution Characteristics of Laryngopharyngeal Reflux in Elderly Patients.

To identify the characteristics of the time-point distribution of the occurrence of hypopharyngeal-proximal reflux episodes (HREs) in elderly and younger patients with laryngopharyngeal reflux (LPR). Retrospective cohort study. Analysis of data from patients with LPR-related symptoms and 24-hour hypopharyngeal-esophageal multichannel intraluminal impedance-pH (24-hour HEMII-pH) monitoring from February 2017 to September 2022 at Sixth Medical Center of PLA General Hospital. Patients were divided into 2 age groups: the elderly group (>60 years) and the younger group (≤60 years). The time series of HREs and meals within 24hours were analyzed based on HEMII-pH. A total of 305 patients were included (126 elderly patients). In younger patients, except for nonacid-gas HREs, the incidence of the remaining types of HREs tended to increase within 2hours after meals, especially after dinner. The incidence of all types of HREs pre- and postmeal was not significantly different in the elderly group (χ2 = 0.080, P = .777). The incidence of nighttime HREs in elderly patients was statistically higher than in younger patients (6.23% vs3.96%, P = .030), particularly acid-/nonacid-liquid HREs. HREs tend to increase within 2hours after meals in younger LPR patients, except for nonacid-gas HREs. In elderly LPR patients, the incidence of all types of HREs pre- and postmeal were not significantly different, and nighttime fluid HREs was more prone to occur than in younger patients.

Relationship Between Laryngopharyngeal Reflux and Obstructive Sleep Apnea in Adult Males

To investigate the relationship between laryngopharyngeal reflux (LPR) and obstructive sleep apnea (OSA). Patients diagnosed with OSA who were hospitalized in the Department of Otolaryngology-Head and Neck Surgery from November 2021 to April 2022 were selected, and male patients with non-OSA during the same period were selected as the control group. Patients who participated in the study completed the Reflux Symptom Index (RSI), the Reflux Finding Sign (RFS), and 24-hour multichannel intraluminal impedance-pH (MII-pH) monitoring. RSI, RFS, and outcomes of 24hour-MII-pH monitoring were compared between the OSA group and the control group. A total of 86 patients were enrolled, of whom 49 were OSA patients and 37 were non-OSA patients. The positive rate of LPR (97.96% vs75.68%) and the median number of LPR episodes (9 vs5) were significantly higher in OSA patients than in non-OSA patients (P<0.01, P<0.05, respectively). A logistic regression model including body mass index, alcohol consumption, and the presence of OSA showed that having OSA was a risk factor for the occurrence of LPR (P<0.05,OR [odds ratio]=9.995, 95% CI [confidence interval] 1.084-92.181). There were correlations between Apnea-Hypopnea Index and the number of non-acid LPR episodes and the number of alkaline LPR episodes (r=0.243,P<0.05, r=0.274, P<0.05,respectively). Having OSA is a risk factor for LPR, and LPR episodes occur more frequently in patients with OSA compared to those without OSA. When OSA is comorbid with LPR, the occurrence of alkaline LPR, such as bile reflux, should be a concurrent concern.

Prevalence of gastroesophageal reflux disease in children with extraesophageal manifestations using combined-video, multichannel intraluminal impedance-pH study

Gastroesophageal reflux disease (GERD) might be either a cause or comorbidity in children with extraesophageal problems especially as refractory respiratory symptoms, without any best methods or criterion for diagnosing it in children.To evaluate the prevalence of extraesophageal GERD using conventional and combined-video, multichannel intraluminal impedance-pH (MII-pH), and to propose novel diagnostic parameters.The study was conducted among children suspected of extraesophageal GERD at King Chulalongkorn Memorial Hospital between 2019 and 2022. The children underwent conventional and/or combined-video MII-pH. The potential parameters were assessed and receiver operating characteristic was used for the significant parameters.Of 51 patients (52.9% males), aged 2.24 years were recruited. The common problems were cough, recurrent pneumonia, and hypersecretion. Using MII-pH, 35.3% of the children were diagnosed with GERD by reflux index (31.4%), total reflux events (3.9%), and symptom indices (9.8%) with higher symptom recorded in the GERD group (94 vs 171, P = 0.033). In the video monitoring group (n = 17), there were more symptoms recorded (120 vs 220, P = 0.062) and more GERD (11.8% vs 29.4%, P = 0.398) by symptom indices. Longest reflux time and mean nocturnal baseline impedance were significant parameters for diagnosis with receiver operating characteristic areas of 0.907 (P = 0.001) and 0.726 (P = 0.014).The prevalence of extraesophageal GERD in children was not high as expected. The diagnostic yield of symptom indices increased using video monitoring. Long reflux time and mean nocturnal baseline impedance are novel parameters that should be integrated into the GERD diagnostic criteria in children.

How Best to Estimate Insertion Length of Multichannel Intraluminal Impedance pH Probes in Children

To assess the reliability of the KidZ Health Castle formula (KHC-F) to determine the correct probe position of a multichannel intraluminal impedance pH. A retrospective cohort study was performed on 222 children between 1month and 18years of age undergoing multichannel intraluminal impedance pH. The primary outcome was the comparison of the pH sensor location determined by the KHC-F with the radiological target position. The margin of error was defined as 1 cm from the target position. Performance of the KHC-F and existing formulas was determined via the percentage with a correct position, mean error, 95% limits of agreement (Bland-Altman plots), and Spearman correlation. A post hoc analysis was performed with an updated KHC-F v2, subtracting -0.5cm from the KHC-F. Positioning with KHC-F was correct in two-thirds of the participants, with a very strong correlation (ρ = 0.91) with the target position. Bland-Altman plots showed good agreement between KHC-F and target position (mean error of -0.44cm, lower limit -3.2cm, upper limit 2.3cm). A post hoc analysis with the KHC-F v2 showed a correct positioning in 74% of patients. Comparison with other formulas showed a stronger performance of KHC-F and KHC-F v2 on correct positioning, mean error, and 95% limits of agreement. The KHC-F leads to reliable results. KHC-F v2 outperforms all other existing formulas in children, thereby reducing the need for repositioning and the amount of x-ray exposure. The age distribution of the sample may be a limitation, as well as the retrospective nature of the study.

Relevance of Excessive Air Swallowing in GERD Patients With Concomitant Functional Dyspepsia and Poor Response to PPI Therapy.

The present study was aimed at evaluating the possible role of air swallowing in the association between gastroesophageal reflux disease (GERD) symptoms and concomitant functional dyspepsia (FD) and their role in GERD symptom persistence despite proton pump inhibitor (PPI) therapy. It has been shown that individuals with excessive air swallowing experience FD. It has been also demonstrated that a consistent group of GERD patients not responding to PPI therapy swallow more air during mealtime and also have more mixed refluxes. Multichannel intraluminal impedance-pH tracings from consecutive patients were retrospectively evaluated. A validated structured questionnaire was used to evaluate GERD and concomitant FD symptoms. All patients were treated, within the previous year, with at least 8 weeks of standard-dose PPI therapy. A total of 35 patients with conclusive GERD, 35 patients with reflux hypersensitivity, and 35 with functional heartburn were studied. A direct relationship was observed between the number of air swallows and of mixed refluxes ( R =0.64). At receiver operating characteristic curve analysis, air swallows and mixed refluxes were significantly associated to the presence of FD and PPI refractoriness. An air swallow cutoff of 107 episodes/24 hours was identified to discriminate patients with and without FD (sensitivity: 87%, specificity: 82.8%). A mixed reflux cutoff of 34 episodes/24 hours was identified to discriminate PPI responders from nonresponders (sensitivity: 84.8%, specificity: 69%). At multivariate analysis, an abnormal number of air swallows and of mixed refluxes were significantly associated to FD and PPI refractoriness. Our study highlights the relevant role of excessive air swallowing in eliciting both dyspepsia and refractoriness of typical GERD symptoms to PPI therapy.

Elucidation of gastric motor function caused by gastroesophageal reflux in Rumination syndrome

Rumination syndrome (RS) is a disease of the gastrointestinal (GI) tract characterised by repeated regurgitation of recently digested food back into the mouth. It can be difficult to distinguish from gastro-oesophageal reflux disease (GERD) and it is likely that many RS patients are treated for GERD due to being misdiagnosed. Assistant Professor Kenichiro Nakagawa is leading a team of experts based in the Division of Gastroenterology, Tohoku University Graduate School of Medicine, Japan, investigating the causes of gastroesophageal reflux. The researchers have already found that RS and GERD are very different in terms of pathology. They are using high-resolution impedance manometry (HRIM) as a diagnostic tool to comprehensively assess the motor function and bolus transit of food through the oesophagus. They are also utilising oesophageal multichannel intraluminal impedance-pH (MII-pH) monitoring to assess the pH of targeted oesophageal and gastric regions of the GI tract. In doing so, the team can pinpoint gastroesophageal reflux patterns, in turn highlighting the differences in gastroesophageal reflux patterns between RS and GERD patients and healthy control subjects. Using oesophagogastric scintigraphy, the researchers can compare the ratio of regurgitated food during gastroesophageal reflux in their three test groups, analysing where the food residue in RS and GERD patients and healthy control subjects localises in the proximal stomach.

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.

Pediatric Laryngopharyngeal Reflux: An Evidence-Based Review

Pediatric laryngopharyngeal reflux (P-LPR) is associated with the development of common otolaryngological symptoms and findings. In the present study, the findings about epidemiology, clinical presentation, diagnostic and therapeutic outcomes of pediatric population were reviewed. A PubMed, Cochrane Library, and Scopus literature search was conducted about evidence-based findings in epidemiology, clinical presentation, diagnostic and therapeutic outcomes of P-LPR. The prevalence of LPR remains unknown in infant and child populations. The clinical presentation depends on age. Infants with LPR symptoms commonly have both gastroesophageal reflux disease (GERD) and laryngopharyngeal reflux and related digestive, respiratory and ear, nose and throat symptoms. The GERD prevalence appears to decrease over the growth, and the clinical picture is increasingly associated with LPR symptoms and findings without GERD. The prevalence of LPR and proximal acid and nonacid esophageal reflux events may be high in some prevalent otolaryngological conditions (chronic otitis media, laryngolomalacia and apnea). However, the lack of use of hypopharyngeal-esophageal multichannel intraluminal impedance pH monitoring (HEMII-pH) limits the establishment of etiological associations. Proton pump inhibitors are less effective in P-LPR patients compared to GERD populations, which may be related to the high prevalence of weakly or nonacid reflux events. Many gray areas persist in P-LPR and should be not resolved without the establishment of diagnostic criteria (guidelines) based on HEMII-pH. The unavailability of HEMII-pH and the poor acid-suppressive therapeutic response are all issues requiring future investigations. Future controlled studies using HEMII-pH and enzyme measurements in ear, nose or throat fluids may clarify the epidemiology of P-LPR according to age and its association with many otolaryngological conditions.