24-h Multichannel Intraluminal impedance-pH Monitoring Research Articles

Inflammatory responses in esophageal mucosa before and after laparoscopic antireflux surgery.

Currently, the primary treatment for gastroesophageal reflux is acid suppression with proton pump inhibitors, but they are not a cure, and some patients don't respond well or refuse long-term use. Therefore, alternative therapies are needed to understand the disease and develop better treatments. Laparoscopic anti-reflux surgery (LARS) can resolve symptoms of these patients and plays a significant role in evaluating esophageal healing after preventing harmful effects. Successful LARS improves typical gastroesophageal reflux symptoms in most patients, mainly by reducing the exposure time to gastric contents in the esophagus. Amelioration of the inflammatory response and a recovery response in the esophageal epithelium is expected following the cessation of the noxious attack. To explore the role of inflammatory biomolecules in LARS and assess the time required for esophageal epithelial recovery. Of 22 patients with LARS (pre- and post/5.8 ± 3.8 months after LARS) and 25 healthy controls (HCs) were included. All subjects underwent 24-h multichannel intraluminal impedance-pH monitoring and upper gastrointestinal endoscopy, during which esophageal biopsy samples were collected using endoscopic techniques. Inflammatory molecules in esophageal biopsies were investigated by reverse transcription-polymerase chain reaction and multiplex-enzyme-linked immunosorbent assay. Post-LARS samples showed significant increases in proinflammatory cytokines [interleukin (IL)-1β, interferon-γ, C-X-C chemokine ligand 2 (CXCL2)], anti-inflammatory cytokines [CC chemokine ligand (CCL) 11, CCL13, CCL17, CCL26, CCL1, CCL7, CCL8, CCL24, IL-4, IL-10], and homeostatic cytokines (CCL27, CCL20, CCL19, CCL23, CCL25, CXCL12, migration inhibitory factor) compared to both HCs and pre-LARS samples. CCL17 and CCL21 levels were higher in pre-LARS than in HCs (P < 0.05). The mRNA expression levels of AKT1, fibroblast growth factor 2, HRAS, and mitogen-activated protein kinase 4 were significantly decreased post-LARS vs pre-LARS. CCL2 and epidermal growth factor gene levels were significantly increased in the pre-LARS compared to the HCs (P < 0.05). The presence of proinflammatory proteins post-LARS suggests ongoing inflammation in the epithelium. Elevated homeostatic cytokine levels indicate cell balance is maintained for about 6 months after LARS. The anti-inflammatory response post-LARS shows suppression of inflammatory damage and ongoing postoperative recovery.

Characteristics of reflux and gastric electrical activity in gastroesophageal reflux disease with ineffective esophageal motility.

The impact of ineffective esophageal motility (IEM) on gastroesophageal reflux disease (GERD) remains unknown, and abnormal esophageal motility often coexists with abnormal gastric motility. We aimed to investigate the role of IEM in GERD and its relationship with gastric electrical activity. Patients diagnosed as GERD based on GERD-questionnaire score ≥8 in our hospital from January 2020 to June 2022 were included. All patients underwent 24-h multichannel intraluminal impedance-pH monitoring, high-resolution manometry, and electrogastrogram and were categorized into the normal esophageal motility (NEM) and IEM groups, respectively. Reflux characteristics and gastric electric activity were compared between the two groups, and the correlation between gastric electric activity and reflux was analyzed. Acid exposure time, total reflux episodes, and DeMeester score in the IEM group were higher than those in the NEM group. Distal mean nocturnal baseline impedance was significantly lower in the IEM group. Compared with the NEM group, the power ratio (PR) of fundus, antrum and pylorus and premeal and postmeal normal wave ratio of antrum were significantly lower in IEM. The total reflux episodes were negatively correlated with the PR of fundus and pylorus, and the DeMeester score was negatively correlated with the PR of corpus and pylorus. IEM may lead to increased reflux, resulting in esophageal mucosal damage. There may be consistency between abnormal esophageal motility and gastric motility.

Correlation of Esophageal Mean Nocturnal Baseline Impedance With Markers of Laryngopharyngeal Reflux.

Mean nocturnal baseline impedance (MNBI) is a measure of the esophageal epithelial barrier function calculated via high-resolution impedance manometry and can be used as a diagnostic tool and treatment response predictor for gastroesophageal reflux disease (GERD). However, its utility for laryngopharyngeal reflux (LPR) has been minimally studied. We aimed to investigate the relationship of MNBI between patients with suspected LPR, healthy controls, and their 24-h multichannel intraluminal impedance-pH (MII-pH) study results. Retrospective patient series analysis was performed of patients with suspected LPR and healthy controls who underwent 24-h MII-pH monitoring. MNBI values were calculated from impedance channels at the level of the hypopharynx, proximal esophagus, and distal esophagus. We compared these MNBI values between the subject groups with secondary analysis on MII-pH results, reflux symptom index, reflux findings score, DeMeester score, and salivary pepsin levels. Twenty-three patients with suspected LPR and 14 healthy controls were enrolled. Decreased distal esophageal MNBI was found to be significantly decreased in patients with suspected LPR compared with healthy controls (p< 0.01) and in subjects with positive MII-pH studies compared to negative MII-pH studies (p< 0.01). There were no significant correlations of MNBI at the hypopharynx or proximal esophagus. Distal esophageal MNBI has significant correlations with many phenotypic and biological markers of LPR. These findings indicate that MNBI has the potential to be applied to LPR, similar to its emerging use as a diagnostic tool and treatment response predictor for GERD. 3 Laryngoscope, 133:1927-1932, 2023.

Effect of laparoscopic angle of His reconstruction in the treatment of patients with gastroesophageal reflux disease and hiatal hernia.

Effect of laparoscopic angle of His reconstruction in the treatment of patients with gastroesophageal reflux disease and hiatal hernia.

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

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

The effects of assisted autogenic drainage, combined or not with bouncing on gastroesophageal reflux in infants

This study aimed to determine the effect of assisted autogenic drainage (AAD) with or without bouncing (BAAD) on both acid and non-acid gastroesophageal reflux (GER) in infants <1year. During a 24-h multichannel intraluminal impedance-pH monitoring (MII-pH), infants were treated with a 20-min intervention of AAD (in supine position) or BAAD (in upright position), 2h postprandial. In this controlled trial with intra-subject design, the number of reflux episodes (REs) was the primary outcome measure. The results during AAD and BAAD were compared to a baseline period before intervention and 20min after intervention. Overall, 50 infants were included in both groups. During AAD a significant decrease of RE's was found compared to baseline (p=0.001). No significant differences were found in the BAAD group compared to baseline (p=0.125). AAD and BAAD do not cause or increase GER in infants under the age of 1year.

Association between Laryngopharyngeal Reflux and Vocal Fold Leukoplakia

Introduction: Vocal fold leukoplakia (VFL) has a risk of malignant transformation, and the underlying mechanisms are currently unrecognized. Some clinical evidence has indicated that laryngopharyngeal reflux (LPR) probably plays a critical role. Objective: To explore the risk factors associated with the occurrence of VFL and to investigate the importance of LPR in VFL and its different pathological types using 24-h multichannel intraluminal impedance-pH monitoring. Materials and Methods: Eighty-one patients with VFL and 27 healthy volunteers were recruited. General information and LPR parameters were analyzed. Results: The monitoring showed that 35.8% (29/81) of patients had acidic LPR and that 43.2% (35/81) had weakly acidic LPR. Heavy drinking (odds ratio = 4.004, p = 0.037) and acidic LPR (odds ratio = 4.471, p = 0.029) were independent risk factors for the occurrence of VFL. Acidic LPR showed a strong correlation with the Reflux Finding Score (p < 0.05) in patients suspected of having LPR based on the scale score. Meanwhile, weakly acidic LPR parameters increased with the severity of pathological degrees which were higher in high-grade dysplasia (p < 0.05). Conclusion: Our study confirms the importance of LPR in VFL. Heavy drinking patients with VFL, particularly those with acidic LPR, should undergo intensive treatment. Meanwhile, weakly acidic LPR may play a critical role in the pathological changes in VFL.

878 CLINICAL OUTCOMES OF ENDOSCOPIC ANTI-REFLUX TREATMENT METHODS; ANTI-REFLUX MUCOSECTOMY (ARMS) AND ANTI-REFLUX MUCOSAL ABLATION (ARMA)

Gastroesophageal reflux disease (GERD) is a common disorder with an increasing prevalence worldwide. Proton pump inhibitors (PPIs) are effective in achieving symptom control, however, approximately 30-40% of patients are reported to have persistent symptoms despite PPI therapy. While the surgical intervention such as Laparoscopic Nissen Fundoplication remains the gold standard treatment for refractory GERD, minimally invasive anti-reflux therapies are gaining its popularity to fill in the “gap” of conventional medical therapy and surgery. In 2014, we reported Anti-reflux mucosectomy (ARMS) which utilizes ESD or EMR-C to rebuild the flap valve at the gastric cardia by scarring of the artificial ulcer. In 2018, we developed Anti-reflux mucosal ablation (ARMA) where we apply ablation instead of mucosectomy as an alternative therapy for PPI-refractory GERD. The aim of this study is to evaluate the clinical outcomes of ARMS and ARMA. This is a retrospective, single center study from a prospectively collected database performed between April 2012 and November 2019. The indication of ARMS/ARMA is PPI refractory GERD patients without prominent sliding hernia. In ARMS, ESD or EMR-C at the gastric cardia mucosa was performed in order to create artificial ulcer. In ARMA, mucosal ablation using Triangle Tip Knife with spray coagulation mode (50W-120W, effect 2) was utilized to create the ulcer. The efficacy was evaluated by the patient’s symptom score (Frequent Scale for the Symptoms of GERD: FSSG) and the objective findings; Acid Exposure Time (AET) and DeMeester composite score by 24h multi-channel intraluminal impedance-pH monitoring, before and 2-3 months after procedure. A total of 109 patients (Age 54.0±15.7, M:F 63:46) underwent ARMS, and 24 patients (57.6±15.9, M:F 16:8) underwent ARMA. Mean procedure time (minutes) were 54.7 vs. 35.6, respectively. FSSG score improved from 25.1 to 11.6 (p<0.01) by ARMS and from 25 to 10.5 (p<0.01) by ARMA. By ARMS, AET and DeMeester composite score improved from 20.8 to 6.9 (p < 0.01, n=27) and 64.4 to 24.9 (p < 0.01, n=27), respectively. By ARMA, median AET showed a decreasing trend from 9 to 0.5 (p=0.068, n=8), and the DeMeester composite score significantly improved from 33.5 to 2.8 (p<0.05, n=8). Both ARMS and ARMA were effective anti-reflux therapy methods for PPI-refractory GERD which improved GERD related symptoms and objective acid reflux parameters. ARMA may be advantageous on its easiness and simplicity regarding operative time. A larger study with long-term follow-up is required to confirm these results.

The role of nonacid reflux in laryngopharyngeal reflux diseases.

To analyze the role of nonacid reflux in laryngopharyngeal reflux diseases (LPRD). From January 2014 to April 2019, 344 patients associated with LPRD underwent 24-h multichannel intraluminal impedance-pH monitoring, and their reflux symptom index (RSI) and reflux finding score (RFS) were recorded. The numbers of acid, weakly acidic and alkaline reflux events in the laryngopharynx were counted, and the consistency analysis of the results with the results of the RSI and RFS was conducted. Among the 344 patients, nonacid reflux events accounted for 74.1% (1367/1845) of the all reflux events. There were 111 patients with ≥ 3 acid reflux events, 218 patients with ≥ 3 any kinds of reflux events, and 257 patients with positive results of RSI or RFS. Taking the results of the RSI andor RFS as a reference, the sensitivity, specificity and consistency test Kappa value for the diagnosis of LPRD according to the existence of ≥ 3 acid reflux events were 41.2%, 94.2% and 0.228, respectively.With the existence of three or more all kinds of reflux events as the standard, the sensitivity, specificity and consistency test Kappa value were 76.7%, 74.7% and 0.449, respectively. The nonacid reflux events account for the highest proportion of laryngopharyngeal reflux events, and the consistency of the results of RSI and orRFS with all reflux events is higher than that with only acid reflux events, that indicates nonacid reflux may play an important role in LPRD.

Study on laryngopharyngeal and esophageal reflux characteristics using 24-h multichannel intraluminal impedance-pH monitoring in healthy volunteers.

We aimed to analyze the results of 24-h multichannel intraluminal impedance and pH-monitoring (MII-pH) of the laryngopharynx and esophagus in asymptomatic volunteers. Moreover, we also aimed to gain insight into and establish a baseline for laryngopharyngeal reflux in the healthy population by quantitatively and qualitatively comparing the reflux and pH distribution in both the laryngopharynx and the esophagus. Healthy volunteers were recruited and observed; they underwent 24-h ambulatory combined MII-pH monitoring. The proximal sensor (pH1) was positioned approximately 1cm above the upper esophageal sphincter with the aid of a solid-state high-resolution esophageal manometer. Laryngopharyngeal reflux events were detected and characterized by the incidence and property of reflux both in the laryngopharynx and the esophagus. Thirty-eight asymptomatic volunteers who completed all the examinations were included in this study. The median pH detected by the proximal sensor was 6.6 (6.2, 7.0), with an average of 6.58 ± 0.74. A total of 814 laryngopharyngeal reflux events were detected, including 722 (89%) in the upright position and 92 (11%) in the supine position with incidence (0%) in the liquid state, 44 (5%) in the mixture, and 769 (95%) in the gaseous state. Furthermore, 5 incidences (1%) of acid reflux and 809 incidences of non-acid reflux (99%) were noted. A total of 5779 esophageal reflux events were detected, including 5020 (87%) in the upright position, 759 (13%) in the supine position, with 2051 (36%) in the liquid state, 2050 (35%) in the mixed condition, and 1678 (29%) in the gaseous state; adding up to 805 incidences (14%) of acid reflux and 4974 incidences (86%) of non-acid reflux. Non-acid reflux in the upright position is characteristic of laryngopharyngeal reflux. Acid reflux is almost undetectable in healthy subjects. Hence, the diagnostic indicators of gastroesophageal reflux disease are not suitable for laryngopharyngeal reflux disease.

Strong Intra-Esophageal Reflux May Contribute to the Development of Barrett’s Adenocarcinoma and Affect the Localization

Background: There has been no study that has directly measured the esophageal reflux factors in Barrett’s adenocarcinoma (BA) using 24-h multichannel intraluminal impedance-pH monitoring (24-h MII-pH). We aimed to clarify the esophageal reflux factors in Barrett’s esophagus (BE) and BA and the factors that determine the location of BA with 24-h MII-pH. Methods: We performed 24-h MII-pH in 26 patients with superficial BA treated endoscopically (BA group) and 13 patients with BE (BE group) and examined the esophageal reflux factors (esophageal acid exposure time [AET], bolus exposure (acid, weakly acid, and alkaline), and number of reflux episodes. In the BA group, there were 16 cases in which the lesions were localized in an area in contact with the esophagogastric junction (EGJ; EGJ group), and 10 cases in which the lesions were proximal to the BE and separated from the EGJ (non-EGJ group). Results: Total reflux in the bolus exposure in the BA group showed higher values compared to that in the BE group. The total of acid and weakly acid reflux of bolus exposure was significantly higher in the BA group than that in the BE group. The BA group also had greater numbers of total reflux episodes than the BE group. As for the cancer locations in BE, the cases in which the lesions were located proximally and separated from the EGJ had more AET and total reflux and acid reflux indicated by bolus exposure compared to the lesions adjacent to the EGJ. Conclusions: Stronger gastro-esophageal reflux appeared to be an important factor in the development of adenocarcinoma from BE. In addition, the cancer location in BE may be related to the intensity of esophageal reflux.

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.

Standard values of 24-h multichannel intraluminal impedance–pH monitoring for the Japanese

Background Combined multichannel intraluminal impedance and pH monitoring (MII–pH) is the gold standard for diagnosing gastroesophageal reflux (GER), but there are no concrete data for a Japanese population. The aim of this study is to determine the standard values of MII–pH for a Japanese population.

Tailored therapy for the refractory GERD patients by combined multichannel intraluminal impedance-pH monitoring.

About 30% of patients with gastroesophageal reflux disease (GERD) are refractory to proton pump inhibitor (PPI). The reason for the PPI failure in Asian GERD patients has rarely been studied, and the therapy remained unclear. The aims were to explore the possible reasons for PPI failure and to treat these patients with the guidance of 24-h multichannel intraluminal impedance-pH (MII-pH) monitoring. Thirty-nine consecutive patients with refractory GERD were enrolled; 24-h MII-pH monitoring was performed on PPI. The refractory GERD patients were grouped into acid overexposure, non-acid reflux, and functional heartburn after the MII-pH monitoring. Double dose of either PPI or paroxetine was administered to refractory GERD patients within different groups. The number of patients in groups of acid overexposure, non-acid reflux, and functional heartburn was 6, 12, and 21, respectively. The acid overexposure group had the most acid reflux events. Among the acid overexposure group, five (5/6) patients accomplish symptom relief with double dose of esomeprazole. For the patients in non-acid reflux group, double dose of esomeprazole made half (6/12) of the patients obtain symptom relief. For the patients in functional heartburn group, the paroxetine had relieved the symptoms in 14 patients among all the 21 patients. In total, with the guidance of MII-pH monitoring, 64.1% (25/39) of refractory GERD patients accomplished symptom relief. Acid overexposure, non-acid reflux, and functional heartburn were the common reasons for persistent reflux symptoms despite PPI. With the guidance of MII-pH, a tailored therapy could resolve the persistent reflux symptoms among two-third of patients.

The Clinical Value of Deflation Cough in Chronic Coughers With Reflux Symptoms

Patients with deflation cough (DC), the cough-like expulsive effort(s) evoked by maximal lung emptying during a slow vital capacity maneuver, also present symptoms of gastroesophageal reflux. DC can be inhibited by prior intake of antacids. We wished to assess DC prevalence and association between DC and chemical characteristics of refluxate in patients with gastroesophageal reflux symptoms. A total of 157 consecutive outpatients underwent DC assessment and 24-h multichannel intraluminal impedance pH (MII-pH) monitoring; 93/157 also had chronic cough. Patients performed two to four slow vital capacity maneuvers and DC was detected aurally. Subsequently, they underwent 24-h MII-pH monitoring, the outcomes of which were defined as abnormal when acid or non-acid reflux events were >73. DC occurred in 46/157 patients, 18 of whom had abnormal MII-pH outcomes; 28 of the remaining 111 patients without DC also had abnormal MII-pH findings. Thus, in the patients as a group, there was no association between DC and MII-pH outcomes. DC occurred in 40/93 of the chronic coughers; 15 of whom had acid reflux. All but 2 of the 53 patients without DC had normal MII-pH outcomes (P< .001), and the negative predictive value of DC for excluding acid reflux was 96.2%. At follow-up, 65%of coughers showed significant improvement after treatment. The overall prevalence of DC was 29%, increasing to 43%in chronic coughers in whom the absence of DC virtually excludes acid reflux. Therefore, DC assessment may represent a useful screening test for excluding acid reflux in chronic coughers with reflux symptoms.

24-h multichannel intraluminal impedance-pH monitoring may be an inadequate test for detecting gastroesophageal reflux in patients with mixed typical and atypical symptoms.

The detection of gastroesophageal reflux (GERD) via pH testing is the key component of the evaluation of patients considered for antireflux surgery. Two common pH testing systems exist, a multichannel, intraluminal impedance-pH monitoring (MII-pH) catheter, and wireless (Bravo(®)) capsule; however, discrepancies between the two systems exist. In patients with atypical symptoms, MII-pH catheter is often used preferentially. We aimed to elucidate the magnitude of this discrepancy and to assess the diagnostic value of MII-pH and the Bravo wireless capsule in a population of patients with mixed respiratory and typical symptoms. The study population consisted of 66 patients tested with MII-pH and Bravo pH testing within 90 days between July 2009 and 2013. All patients presented with laryngo-pharyngo-respiratory (LPR) symptoms. Patient demographics, symptomatology, manometric and endoscopic findings, and pH monitoring parameters were analyzed. Patients were divided into four comparison groups: both pH tests positive, MII-pH negative/Bravo positive, MII-pH positive/Bravo negative, and both pH tests negative. Nearly half of the patients (44%) had discordant pH test results. Of these, 90% (26/29) had a negative MII-pH but positive Bravo study. In this group, the difference in the DeMeester score was large, a median of 29.3. These patients had a higher BMI (28.5 vs. 26.1, p = 0.0357), were more likely to complain of heartburn (50 vs. 23%, p = 0.0110), to have a hiatal hernia, (85 vs. 53%, p = 0.0075) and a structurally defective lower esophageal sphincter (LES, 85 vs. 58%, p = 0.0208). In patients with LPR symptoms, we found a high prevalence of discordant esophageal pH results, most commonly a negative MII-pH catheter and positive Bravo. As these patients exhibited characteristics consistent with GERD (heartburn, defective LES, hiatal hernia), the Bravo results are likely true. A 24-h MII-pH catheter study may be inadequate to diagnose GERD in this patient population.

Impedance-pH monitoring and conventional pH monitoring are complementary methods to detect association between gastroesophageal reflux and apnea-related symptoms in preterm infants and neonates

Objective: To investigate the usefulness of Multichannel intraluminal impedance-pH (MII-pH) monitoring as compared with conventional pH monitoring for detecting Gastroesophageal reflux (GER) episodes and apnea-related symptom association in preterm infants and neonates. Methods: Twenty-three infants (16 preterm and 7 term infants) in hospital, who underwent 24-h MII-pH monitoring, were studied retrospectively. GER indices and apnea-related symptom association were measured by both MII-pH and conventional pH based analysis. Results: Of the total 998 GER episodes assessed by MII-pH monitoring, 407 (40.8%) were acidic and 590 (59.1%) were weakly acidic. A total of 1689 GER episodes were detected by conventional pH based analysis and 270 (16%) were related to retrograde bolus movement. A total of 313 apnea-related symptoms were reported. Five patients had a positive symptom association: 3 by MII-pH, 1 by both MII-pH and conventional pH, 1 only by conventional pH. Conclusions: Addition of MII-pH monitoring to conventional pH monitoring improves the diagnostic yield of symptom association analysis in preterm infants and neonates with apnea-related symptoms. Conventional pH monitoring is still important in the era of impedance measurement.

Reflux patterns in patients with short‐segment Barrett’s oesophagus: a study using impedance‐pH monitoring off and on proton pump inhibitor therapy

In short-segment Barrett's oesophagus (SSBO) heartburn may be absent and oesophageal acid exposure time (OAET) assessed with pH-only monitoring may be normal. By detecting reflux episodes independently of their acidity, multichannel intraluminal impedance-pH (MII-pH) monitoring allows a comprehensive characterization of reflux events, either off or on proton pump inhibitor (PPI) therapy. To assess reflux parameters by MII-pH monitoring in newly diagnosed SSBO, at baseline and as modified with PPI therapy. Short-segment Barrett's oesophagus was defined by oesophageal intestinal metaplasia up to 3 cm in length. 24-h MII-pH monitoring was performed before and during PPI therapy. Fifty patients were studied prospectively. Normal OAET was found at baseline in 15 patients (30%), 8 and 2 of whom with a higher than normal number of acid and weakly acidic refluxes, respectively. Overall, abnormal reflux parameters were detected by MII-pH monitoring in 90% of patients. Reflux events were prevalent in the upright period. On PPI therapy, acid refluxes decreased and a correspondent increase in weakly acidic refluxes was observed (median from 48.5 to 9 and from 16 to 57.5, respectively) (P < 0.001). Acid refluxes, mainly in the upright period, characterize SSBO. PPI therapy transforms acid refluxes into weakly acidic refluxes.

Altered Esophageal Motility and Gastroesophageal Barrier in Patients with Jejunal Interposition After Distal Esophageal Resection for Early Stage Adenocarcinoma

IntroductionLimited resection of the esophagogastric junction has been proven to be safe and oncologically radical in patients with early esophageal cancer. Reconstruction with interposition of isoperistaltic jejunal loop (Merendino procedure) is supposed to prevent gastroesophageal reflux and therefore the recurrence of intestinal metaplasia at the anastomosis. The aim of this study was to assess the frequency of acid and nonacid refluxes after Merendino procedure using multichannel intraluminal impedance-pH (MII-pH) monitoring. Patients and MethodsBetween 2002 and 2005, 12 patients with esophageal adenocarcinoma underwent limited resection and jejunal interposition. Ten patients agreed to undergo a Gastrointestinal Symptom Rating Scale assessment, upper gastrointestinal (GI) endoscopy, esophageal manometry, and combined 24-h MII-pH monitoring more than 10 months postoperatively. ResultsPostoperatively, 4 (40%) patients reported belching without heartburn or acid regurgitation, 3 of them having a positive symptom index during 24-h MII-pH monitoring. Upper GI endoscopy revealed no inflammation, metaplasia, or stenosis at the esophagojejunal anastomosis. Esophageal manometry showed ineffective esophageal motility in four of ten patients. Combined 24-h MII-pH monitoring revealed normal distal esophageal acid exposure (% time pH < 4: 0.1% [0–1.5]), normal number of acid reflux episodes (3 [0–11]) but a high number of nonacid reflux episodes (82 [33–184]). Overall, eight patients revealed an abnormal number of nonacid reflux episodes. ConclusionThe limited resection with jejunal interposition for early esophageal cancer is efficient in controlling acid but not nonacid reflux. While the clinical relevance of nonacid reflux in the recurrence of Barrett’s esophagus is currently unknown, endoscopic surveillance should be considered in these patients.