Esophageal secondary peristalsis following acid infusion and chemical clearance correlate with mucosal integrity and acid sensitivity in GERD patients

Background

Acid sensitivity can be altered in patients with gastroesophageal reflux disease (GERD). Secondary peristalsis helps clear gastro-esophageal refluxate and residual ingested food bolus.

Objectives

The aim of this study was to investigate the associations among acid sensitivity, esophageal mucosal integrity, chemical clearance, and secondary peristalsis before and after esophageal acid infusion.

Design

This was an investigator-initiated, prospective, cross-sectional study.

Methods

Adult reflux patients underwent high resolution manometry and 24 h impedance-pH monitoring off acid suppression to identify GERD phenotypes, including non-erosive reflux disease (NERD), reflux hypersensitivity (RH), and functional heartburn (FH). Secondary peristalsis was assessed using five rapid 20 mL air injections into the esophagus before and after infusion of hydrochloric acid (0.1 N) into the mid-esophagus. Conventional acid infusion parameters recorded included lag time, intensity rating, and sensitivity score. Chemical clearance was evaluated using the post-reflux swallow-induced peristaltic wave (PSPW), and mucosal integrity was assessed by the mean nocturnal baseline impedance (MNBI) derived from impedance-pH monitoring.

Results

A total of 88 patients (age 21-64 years, 62.5% women) completed the study including 12 patients with NERD, 45 with RH, and 31 with FH. There was no significant difference in acid infusion parameters between patients with NERD, RH, and FH. Upon acid infusion, patients who exhibited successful secondary peristalsis had longer lag time, higher MNBI, and shorter bolus contact time than those without secondary peristalsis. Meanwhile, patients with intact PSPW demonstrated significantly higher intensity ratings in response to acid perfusion and higher MNBI than those with impaired PSPW. The lag time correlated positively with MNBI (r = 0.285; p = 0.007).

Conclusion

In conclusion, the protective effect of esophageal secondary peristalsis and chemical clearance on esophageal mucosal integrity was demonstrated. Concerning acid sensitivity, longer lag time in patients with intact secondary peristalsis may be attributed to better esophageal mucosal integrity, while stronger intensity ratings may have a greater tendency to induce PSPW and protect esophageal mucosal integrity.

Analysis of contractile segment impedance during straight leg raise maneuver using high-resolution impedance manometry increases diagnostic yield in reflux disease

BACKGROUND

Contractile segment impedance (CSI) obtained from high-resolution impedance manometry (HRIM) is a measure of mucosal integrity that predicts gastroesophageal reflux disease (GERD). While straight leg raise (SLR) maneuver augments esophageal peristaltic vigor, it remains unclear whether SLR affects CSI values. This study was aimed to evaluate whether CSI with SLR is feasible and useful to complement the diagnosis of GERD.

METHODS

We prospectively recruited 48 patients with typical GERD symptoms who underwent esophagogastroduodenoscopy, HRIM with SLR maneuver, and multichannel intraluminal impedance-pH (MII-pH) testing. The capability of mean nocturnal baseline impedance (MNBI), resting baseline impedance (RBI), CSI with or without SLR maneuver in predicting GERD was assessed using receiver operating characteristics (ROC) analysis.

KEY RESULTS

Among 20 GERD patients and 28 non-GERD patients, all values of impedance-based metrics were lower in GERD patients compared to non-GERD patients (p < 0.001). For GERD identification, area under receiver operating characteristic curve (AUROC) values of CSI with SLR maneuver, CSI, MNBI, and RBI were 0.901, 0.858, 0.865, and 0.797. Particularly in ineffective esophageal motility (IEM) patients, SLR maneuver increased mean distal contractile integral from 436 to 828.7 mmHg.s.cm (p = 0.018) and enhanced AUROC values of CSI for GERD identification from 0.917 to 0.958.

CONCLUSIONS & INFERENCES

CSI measurement during HRIM appears to be a reliable, time-saving, and less invasive tool for complementing GERD diagnosis. Our results also suggest a simple SLR maneuver during HRIM could enhance diagnostic accuracy of CSI for GERD identification especially in IEM patients.

Oesophageal hypervigilance and visceral anxiety relate to reflux symptom severity and psychological distress but not to acid reflux parameters

BACKGROUND

The pathogenesis of gastro-oesophageal reflux disease (GERD) is complex and multifactorial. The oesophageal hypervigilance and anxiety scale (EHAS) is a novel cognitive-affective evaluation of visceral sensitivity.

AIMS

To investigate the interrelationship between EHAS and reflux symptom severity, psychological stress, acid reflux burden, phenotypes, and oesophageal mucosal integrity in patients with GERD.

METHODS

Patients with chronic reflux symptoms and negative endoscopy underwent 24-hour impedance-pH monitoring for phenotyping, acid reflux burden, and mucosal integrity with mean nocturnal baseline impedance (MNBI) calculation. Validated scores for patient-reported outcomes, including EHAS, GERD questionnaire (GERDQ), State-Trait Anxiety Inventory score, and Taiwanese Depression Questionnaire score, were recorded.

RESULTS

We enrolled 105 patients, aged 21-64 years (mean, 48.8), of whom 58.1% were female; 27 had non-erosive reflux disease, 43 had reflux hypersensitivity and 35 had functional heartburn. There were no significant differences in sex, EHAS, GERDQ, questionnaires of depression or anxiety among GERD phenotypes. EHAS was significantly correlated with GERDQ, questionnaires of depression and anxiety (P < 0.05). However, there were no significant correlations between GERDQ and questionnaires of depression or anxiety. Regarding patient-reported outcomes, GERDQ positively correlated with acid exposure time and negatively correlated with MNBI (P < 0.05).

CONCLUSIONS

EHAS associates with reflux symptom severity and psychological stress but not with acid reflux burden or mucosal integrity. Thus, EHAS assessment shows promise in assessment of subjective patient outcome and satisfaction with treatment, a hitherto unmet clinical need.

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

Background/Aims

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

Methods

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

Results

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

Conclusion

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

Impact of ineffective esophageal motility on secondary peristalsis: Studies with high-resolution manometry

BACKGROUND/AIM

The aim was to investigate whether there is a difference in secondary peristalsis on high-resolution manometry (HRM) among gastroesophageal reflux disease (GERD) patients with and without ineffective esophageal motility (IEM), and healthy individuals.

METHODS

Twenty-eight GERD patients and seventeen healthy controls were included. Secondary peristalsis was stimulated by a rapid injection of 20 ml air in mid-esophagus. We compared HRM metrics and the response and effective rate of triggering secondary peristalsis between patients with and without IEM and healthy controls.

RESULTS

Sixteen patients had IEM, and the remaining 12 had normal manometry. By triggering of secondary peristalsis, patients without IEM and healthy controls had significantly higher distal contractile integral (DCI) values than IEM patients (p = 0.006). A successful secondary peristalsis was triggered more frequently in healthy controls than in GERD patients with normal peristalsis or IEM (56.9% vs. 20.2% vs. 9.1%, all p < 0.001). The effective rate which determined as DCI > 450 mm Hg.cm.s was higher in healthy controls compared to patients with normal peristalsis (36.5% vs. 19.4%, p < 0.001) and IEM (36.5% vs. 6.3%, p < 0.001). Patients with IEM had lower successful triggering response (9.1% vs. 20.2%) and effective secondary peristalsis (6.3% vs. 19.4%) compared with patients without IEM (p < 0.001).

CONCLUSIONS

Our work has demonstrated that GERD patients, in particular those with IEM, have significant defects in the triggering of secondary peristalsis on HRM. HRM helps characterize esophageal secondary peristalsis which exhibits differently in patients with and without IEM.

Endoscope presence during endoluminal functional lumen imaging probe (FLIP) influences FLIP metrics in the evaluation of esophageal dysmotility

BACKGROUND

The functional lumen imaging probe (FLIP) system is an FDA-approved tool for dynamic evaluation of the esophagogastric junction (EGJ). Even though commercially available since 2009, FLIP utilization remains low, partly due to lack of consensus in methodology and interpretation. Therefore, we aimed to analyze the influence of concurrent endoscopy on FLIP measurements.

METHODS

In this single-center study, we reviewed data from 93 patients undergoing FLIP for symptomatic esophageal motility disorders between 2016 and 2018. During sedated endoscopy, we measured luminal values (distensibility, cross-sectional area (CSA), and balloon pressure) at the EGJ and distal esophagus using 30, 40, and 50 mL distension volumes, with and without concurrent endoscope presence. All recorded values were compared at the various distension volumes between the two measurements using a Wilcoxon rank sum test.

KEY RESULTS

There was a significant difference in distensibility and CSA with index distension volume (40 mL) at the EGJ comparing the two measurements: Lower median distensibility was 2.1 mm²  mm Hg^-1 in the group with concurrent inserted endoscope, respectively, 3.4 mm²  mm Hg^-1 without endoscope (P < .001), and median CSA was 86.0 resp. 110.0 mm² (P < .001). No significant difference could be found in the measurements of the distal esophagus.

CONCLUSIONS & INFERENCES

Our results show a significant difference in FLIP measurements with and without endoscope presence. This underlines the importance of establishing a consensus of a standardized FLIP protocol to define normal luminal values and guiding future FLIP diagnostic studies.

Correlation between reflux burden, peristaltic function, and mucosal integrity in GERD patients

BACKGROUND

Mean nocturnal baseline impedance (MNBI) augments the diagnostic yield of multichannel intraluminal impedance-pH (MII-pH) monitoring. While acid exposure time (AET) correlates with MNBI, it remains unclear whether esophageal motility affects MNBI values. The present study was aimed at evaluating the respective roles of esophageal motor function and AET on MNBI.

METHODS

High-resolution manometry (HRM) studies and ambulatory 24-hour MII-pH monitoring tracings were retrospectively analyzed from consecutive endoscopy-negative GERD patients with typical symptoms responsive to previous acid-suppressive therapy from three tertiary care centers. Univariate and multivariate analyses were performed to determine predictors of pathologic MNBI values at 3 cm and 5 cm above the lower esophageal sphincter (LES).

KEY RESULTS

Patients with pathological AET displayed lower MNBI values at 3 cm and 5 cm (P < .01) compared to patients with non-pathological AET. Similarly, significantly lower MNBI values were also noted at both sites with type 3 EGJ compared to type 1 EGJ (P ≤ .02 for each comparison), and with absent contractility compared to normal peristalsis (P ≤ .02 for each comparison). On multivariate analysis, the presence of type 2 or 3 EGJ and absent contractility were associated with a significantly higher probability of pathological MNBI values at 3 cm and 5 cm above the LES.

CONCLUSIONS AND INFERENCES

Disruption of the EGJ and absent contractility on HRM are both associated with lower MNBI values. HRM findings complement reflux testing using MII-pH monitoring.

How to select patients for antireflux surgery? The ICARUS guidelines (international consensus regarding preoperative examinations and clinical characteristics assessment to select adult patients for antireflux surgery)

OBJECTIVE

Antireflux surgery can be proposed in patients with GORD, especially when proton pump inhibitor (PPI) use leads to incomplete symptom improvement. However, to date, international consensus guidelines on the clinical criteria and additional technical examinations used in patient selection for antireflux surgery are lacking. We aimed at generating key recommendations in the selection of patients for antireflux surgery.

DESIGN

We included 35 international experts (gastroenterologists, surgeons and physiologists) in a Delphi process and developed 37 statements that were revised by the Consensus Group, to start the Delphi process. Three voting rounds followed where each statement was presented with the evidence summary. The panel indicated the degree of agreement for the statement. When 80% of the Consensus Group agreed (A+/A) with a statement, this was defined as consensus. All votes were mutually anonymous.

RESULTS

Patients with heartburn with a satisfactory response to PPIs, patients with a hiatal hernia (HH), patients with oesophagitis Los Angeles (LA) grade B or higher and patients with Barrett's oesophagus are good candidates for antireflux surgery. An endoscopy prior to antireflux surgery is mandatory and a barium swallow should be performed in patients with suspicion of a HH or short oesophagus. Oesophageal manometry is mandatory to rule out major motility disorders. Finally, oesophageal pH (±impedance) monitoring of PPI is mandatory to select patients for antireflux surgery, if endoscopy is negative for unequivocal reflux oesophagitis.

CONCLUSION

With the ICARUS guidelines, we generated key recommendations for selection of patients for antireflux surgery.

The treatment of achalasia patients with esophageal varices: an international study

Background

Treatment options for achalasia include endoscopic and surgical techniques that carry the risk of esophageal bleeding and perforation. The rare coexistence of esophageal varices has only been anecdotally described and treatment is presumed to carry additional risk.

Methods

Experience from physicians/surgeons treating this rare combination of disorders was sought through the International Manometry Working Group.

Results

Fourteen patients with achalasia and varices from seven international centers were collected (mean age 61 ± 9 years). Five patients were treated with botulinum toxin injections (BTI), four had dilation, three received peroral endoscopic myotomy (POEM), one had POEM then dilation, and one patient underwent BTI followed by Heller's myotomy. Variceal eradication preceded achalasia treatment in three patients. All patients experienced a significant symptomatic improvement (median Eckardt score 7 vs 1; p < 0.0001) at 6 months follow-up, with treatment outcomes resembling those of 20 non-cirrhotic achalasia patients who underwent similar therapy. No patients had recorded complications of bleeding or perforation.

Conclusion

This study shows an excellent short-term symptomatic response in patients with esophageal achalasia and varices and demonstrates that the therapeutic outcomes and complications, other than transient encephalopathy in both patients who had a portosystemic shunt, did not differ to disease-matched patients without varices.

The 2018 ISDE achalasia guidelines

Achalasia is a relatively rare primary motor esophageal disorder, characterized by absence of relaxations of the lower esophageal sphincter and of peristalsis along the esophageal body. As a result, patients typically present with dysphagia, regurgitation and occasionally chest pain, pulmonary complication and malnutrition. New diagnostic methodologies and therapeutic techniques have been recently added to the armamentarium for treating achalasia. With the aim to offer clinicians and patients an up-to-date framework for making informed decisions on the management of this disease, the International Society for Diseases of the Esophagus Guidelines proposed and endorsed the Esophageal Achalasia Guidelines (I-GOAL). The guidelines were prepared according the Appraisal of Guidelines for Research and Evaluation (AGREE-REX) tool, accredited for guideline production by NICE UK. A systematic literature search was performed and the quality of evidence and the strength of recommendations were graded according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE). Given the relative rarity of this disease and the paucity of high-level evidence in the literature, this process was integrated with a three-step process of anonymous voting on each statement (DELPHI). Only statements with an approval rate >80% were accepted in the guidelines. Fifty-one experts from 11 countries and 3 representatives from patient support associations participated to the preparations of the guidelines. These guidelines deal specifically with the following achalasia issues: Diagnostic workup, Definition of the disease, Severity of presentation, Medical treatment, Botulinum Toxin injection, Pneumatic dilatation, POEM, Other endoscopic treatments, Laparoscopic myotomy, Definition of recurrence, Follow up and risk of cancer, Management of end stage achalasia, Treatment options for failure, Achalasia in children, Achalasia secondary to Chagas' disease.

Curriculum for neurogastroenterology and motility training: A report from the joint ANMS-ESNM task force

Although neurogastroenterology and motility (NGM) disorders are some of the most frequent disorders encountered by practicing gastroenterologists, a structured competency-based training curriculum developed by NGM experts is lacking. The American Neurogastroenterology and Motility Society (ANMS) and the European Society of Neurogastroenterology and Motility (ESNM) jointly evaluated the components of NGM training in North America and Europe. Eleven training domains were identified within NGM, consisting of functional gastrointestinal disorders, visceral hypersensitivity and pain pathways, motor disorders within anatomic areas (esophagus, stomach, small bowel and colon, anorectum), mucosal disorders (gastro-esophageal reflux disease, other mucosal disorders), consequences of systemic disease, consequences of therapy (surgery, endoscopic intervention, medications, other therapy), and transition of pediatric patients into adult practice. A 3-tiered training curriculum covering these domains is proposed here and endorsed by all NGM societies. Tier 1 NGM knowledge and training is expected of all gastroenterology trainees and practicing gastroenterologists. Tier 2 knowledge and training is appropriate for trainees who anticipate NGM disorder management and NGM function test interpretation being an important part of their careers, which may require competency assessment and credentialing of test interpretation skills. Tier 3 knowledge and training is undertaken by trainees interested in a dedicated NGM career and may be restricted to specific domains within the broad NGM field. The joint ANMS and ESNM task force anticipates that the NGM curriculum will streamline NGM training in North America and Europe and will lead to better identification of centers of excellence where Tier 2 and Tier 3 training can be accomplished.

Diagnostic yield in the evaluation of dysphagia: experience at a single tertiary care center

Evaluation of dysphagia typically starts with esophagogastroduodenoscopy (EGD); further testing is pursued if this is negative. When no mucosal, structural, or motor esophageal disorders are identified with persisting symptoms, functional dysphagia is considered. We evaluated outcomes in patients undergoing EGD for dysphagia, and estimated prevalence of functional dysphagia. The endoscopy database at single tertiary care center was interrogated to identify EGDs performed for an indication of 'dysphagia' over a 12-month period (2008-09). Electronic medical records were reviewed over the next 8 years to assess if an etiology was identified. Data were analyzed to assess the diagnostic yield of endoscopy and subsequent tests in the evaluation of dysphagia. Of 5486 EGDs, 822 (15.0%) were performed for dysphagia in 694 patients (58.4 ± 0.6 year, range: 18-95 year, 55.8% female). Of these, 529 (76.2%) had EGD findings that explained dysphagia; another 22 (3.2%) had findings on histopathology. Of the remainder 143 patients (20.6%) with normal index EGD, 38 (26.6%) patients underwent barium esophagram with 15 (39.5%) having abnormal studies. 19 patients (13.3%) underwent esophageal high resolution manometry with 12 (63.2%) being abnormal, and 7 had a mechanism for dysphagia on alternate testing. A repeat EGD was abnormal in 6 patients, while 45 patients were lost to follow-up. 42 patients had complete resolution of symptoms despite normal endoscopy, of which 30 were treated empirically with a proton pump inhibitor (PPI). Only 16 patients had no findings on evaluation, and had continued dysphagia symptoms, representing true functional dysphagia in 2.3% of all dysphagia patients and 11.2% of patients with normal EGD. Endoscopy remains the test with the highest yield (over 75%) for a diagnosis in patients presenting with dysphagia; secondary tests are useful when endoscopy does not provide a diagnosis. Benign strictures and GERD-related etiologies are leading causes; PPI therapy is useful even when testing is negative. Functional dysphagia is extremely rare, accounting for <2.5% of all dysphagia.

Esophagogastric junction and esophageal body contraction metrics on high-resolution manometry predict esophageal acid burden

BACKGROUND

Distal contractile integral (DCI) and esophagogastric junction contractile integral (EGJ-CI) are high-resolution manometry (HRM) software metrics assessing esophageal motor function in gastroesophageal reflux disease (GERD).

METHODS

Patients undergoing HRM and ambulatory pH monitoring off antisecretory therapy prospectively completed symptom questionnaires assessing symptom burden and a global symptom score (GSS) at baseline and after GERD therapy. DCI<450 mm Hg/cm/s in ≥5 swallows diagnosed ineffective esophageal motility (IEM); proportions of failed (DCI<100 mm Hg/cm/s) and weak (DCI 100-450 mm Hg/cm/s) sequences were separately assessed. EGJ-CI assessed vigor of the EGJ barrier. Univariate and multivariate analyses addressed performance of esophageal body and EGJ metrics in predicting abnormal esophageal reflux burden, and symptom outcome from antireflux therapy.

KEY RESULTS

Of 188 patients (55.2 ± 0.9 year, 64% F), 42.6% had low EGJ-CI, and 25.0% had IEM. While low EGJ-CI was associated with abnormal reflux burden (P = 0.003), IEM alone was not (P = 0.2). Increasing proportions of failed swallows predicted abnormal AET better than the current IEM definition. Combined low EGJ-CI and IEM segregated abnormal total and supine acid burden compared to patients with normal EGJ-CI and no IEM (P ≤ 0.007 for each comparison). Medical therapy and surgical antireflux therapy were similarly effective in improving symptom burden; surgery resulted in better outcomes with low EGJ-CI (P ≤ 0.04), especially with intact esophageal body motor function (P = 0.02).

CONCLUSIONS & INFERENCES

While abnormal EGJ and esophageal body metrics are collectively associated with elevated esophageal reflux burden, increasing proportions of failed swallows are better predictors of reflux burden and outcome compared to the current IEM definition.

Optimal number of multiple rapid swallows needed during high-resolution esophageal manometry for accurate prediction of contraction reserve

BACKGROUND

Multiple rapid swallows (MRS) is a provocative test for assessment of contraction reserve, however reproducibility on repetitive MRS is incompletely understood. Our aim was to determine the optimal number of MRS sequences for consistent assessment of contraction reserve.

METHODS

One hundred and fifty-nine consecutive patients (79 IEM and 80 normal motility) who underwent high-resolution manometers were enrolled. Ten single swallows (SS) and 10 MRS were performed. Gold standard for evaluation of the contraction reserve was the ratio between the mean DCI of 10 MRS and the mean DCI of 10 SS (MRS/SS DCI ratio). Rates of false negatives and false positives were calculated for increasing numbers of MRS sequences, using either mean DCI or the MRS with the highest DCI.

KEY RESULTS

According to the gold standard, 50 IEM and 50 normal motility patients had contraction reserve. With progressively increasing numbers of MRS sequences, contraction reserve was detected using mean MRS DCI within three and four MRS sequences in IEM and normal motility respectively, whereas two and three MRS sequences were needed using the MRS sequence with the highest DCI. False positives were much higher with highest DCI method compared with mean DCI, (22% vs 9% respectively in IEM; 24% vs 9% in normal motility) when three MRS sequences were considered.

CONCLUSIONS & INFERENCES

At least three MRS are needed to reliably assess contraction reserve. The mean DCI of the three MRS sequences is the best variable to utilize as evidence of contraction reserve.

Opioid medication use in patients with gastrointestinal diagnoses vs unexplained gastrointestinal symptoms in the US Veterans Health Administration

BACKGROUND

While opioid prescriptions have increased alarmingly in the United States (US), their use for unexplained chronic gastrointestinal (GI) pain (eg, irritable bowel syndrome) carries an especially high risk for adverse effects and questionable benefit.

AIM

To compare opioid use among US veterans with structural GI diagnoses (SGID) and those with unexplained GI symptoms or functional GI diagnoses (FGID), a group for whom opioids have no accepted role.

METHODS

Veterans Health Administration (VHA) administrative data from fiscal year 2012 were used to identify veterans with diagnostic codes recorded for SGID and FGID. This cohort study examined VHA pharmacy data to compare groups receiving ≥ 1 opioid prescription during the year and number of prescriptions filled. Bivariate and multiple logistic regression analyses adjusted for potential confounding factors (demographics, medical diagnoses, social factors) and identified potential mediators (service use, psychiatric comorbidity) of opioid use in these groups.

RESULTS

A greater proportion of veterans with FGID received an opioid prescription during fiscal year 2012 (36.0% of 272 431) compared to only 28.9% of 1 223 744 in the SGID group (Relative Risk [RR] = 1.25). In multivariate logistic regression, personality disorders and drug abuse (OR 1.23 for each group), recent homelessness (OR 1.22), psychotropic medication fills (OR 1.55) and emergency department encounters (OR 1.21) were independently associated with opioid prescription use.

CONCLUSIONS

Despite the potential for adverse consequences, opioids more often are prescribed for veterans with chronic, unexplained GI symptoms compared to those with structural diagnoses. Psychiatric comorbidities and frequent healthcare encounters mediate some of the opioid use risk.

Classification of esophageal motor findings in gastro-esophageal reflux disease: Conclusions from an international consensus group

BACKGROUND

High-resolution manometry (HRM) has resulted in new revelations regarding the pathophysiology of gastro-esophageal reflux disease (GERD). The impact of new HRM motor paradigms on reflux burden needs further definition, leading to a modern approach to motor testing in GERD.

METHODS

Focused literature searches were conducted, evaluating pathophysiology of GERD with emphasis on HRM. The results were discussed with an international group of experts to develop a consensus on the role of HRM in GERD. A proposed classification system for esophageal motor abnormalities associated with GERD was generated.

KEY RESULTS

Physiologic gastro-esophageal reflux is inherent in all humans, resulting from transient lower esophageal sphincter (LES) relaxations that allow venting of gastric air in the form of a belch. In pathological gastro-esophageal reflux, transient LES relaxations are accompanied by reflux of gastric contents. Structural disruption of the esophagogastric junction (EGJ) barrier, and incomplete clearance of the refluxate can contribute to abnormally high esophageal reflux burden that defines GERD. Esophageal HRM localizes the LES for pH and pH-impedance probe placement, and assesses esophageal body peristaltic performance prior to invasive antireflux therapies and antireflux surgery. Furthermore, HRM can assess EGJ and esophageal body mechanisms contributing to reflux, and exclude conditions that mimic GERD.

CONCLUSIONS & INFERENCES

Structural and motor EGJ and esophageal processes contribute to the pathophysiology of GERD. A classification scheme is proposed incorporating EGJ and esophageal motor findings, and contraction reserve on provocative tests during HRM.

Ambulatory reflux monitoring for diagnosis of gastro-esophageal reflux disease: Update of the Porto consensus and recommendations from an international consensus group

BACKGROUND

An international group of experts evaluated and revised recommendations for ambulatory reflux monitoring for the diagnosis of gastro-esophageal reflux disease (GERD).

METHODS

Literature search was focused on indications and technical recommendations for GERD testing and phenotypes definitions. Statements were proposed and discussed during several structured meetings.

KEY RESULTS

Reflux testing should be performed after cessation of acid suppressive medication in patients with a low likelihood of GERD. In this setting, testing can be either catheter-based or wireless pH-monitoring or pH-impedance monitoring. In patients with a high probability of GERD (esophagitis grade C and D, histology proven Barrett's mucosa >1 cm, peptic stricture, previous positive pH monitoring) and persistent symptoms, pH-impedance monitoring should be performed on treatment. Recommendations are provided for data acquisition and analysis. Esophageal acid exposure is considered as pathological if acid exposure time (AET) is greater than 6% on pH testing. Number of reflux episodes and baseline impedance are exploratory metrics that may complement AET. Positive symptom reflux association is defined as symptom index (SI) >50% or symptom association probability (SAP) >95%. A positive symptom-reflux association in the absence of pathological AET defines hypersensitivity to reflux.

CONCLUSIONS AND INFERENCES

The consensus group determined that grade C or D esophagitis, peptic stricture, histology proven Barrett's mucosa >1 cm, and esophageal acid exposure greater >6% are sufficient to define pathological GERD. Further testing should be considered when none of these criteria are fulfilled.

The learning curve for interpretation of oesophageal high-resolution manometry: a prospective interventional cohort study

BACKGROUND

High-resolution manometry has become the preferred choice of oesophagologists for oesophageal motor assessment, but the learning curve among trainees remains unclear.

AIM

To determine the learning curve of high-resolution manometry interpretation.

METHODS

A prospective interventional cohort study was performed on 18 gastroenterology trainees, naïve to high-resolution manometry (median age 32 ± 4.0 years, 44.4% female). An intake questionnaire and a 1-h standardised didactic session were performed at baseline. Multiple 1-h interpretation sessions were then conducted periodically over 15 months where 10 studies were discussed; 5 additional test studies were provided for interpretation, and results were compared to gold standard interpretation by the senior author. Hypothetical management decisions based on trainee interpretation were separately queried. Accuracy was compared across test interpretations and sessions to determine the learning curve, with a goal of 90% accuracy.

RESULTS

Baseline accuracy was low for abnormal body motor patterns (53.3%), but higher for achalasia/outflow obstruction (65.9%). Recognition of achalasia reached 90% accuracy after six sessions (P = 0.01), while overall accurate management decisions reached this threshold by the 4th session (P < 0.001). Based on our data, the threshold of 90% accuracy for recognition of any abnormal from normal pattern was reached after 30 studies (3rd session) but fluctuated. Diagnosis of oesophageal body motor patterns remained suboptimal; accuracy of advisability of fundoplication improved, but did not reach 90%.

CONCLUSIONS

High-resolution manometry has a steep learning curve among trainees. Achalasia recognition is achieved early, but diagnosis of other abnormal motor patterns and management decisions require further supervised training.

Changes in symptom reflux association using dynamic pH thresholds during ambulatory pH monitoring: an observational cross-sectional study

Symptom reflux association (SRA) assesses symptoms associated with reflux events defined by pH <4.0, but limited symptoms associate with reflux events. We evaluated the impact of alternate pH thresholds on SRA in a large ambulatory pH database. Acid exposure time (AET), reflux events, and associated symptoms (within 2 minutes following a reflux event) were extracted from ambulatory pH studies performed off antireflux therapy (722 patients, 49.1 ± 0.5 years, 66.8% F) over a 7-year period. Symptom association probability (SAP) and symptom index (SI) were calculated at pH 3.5, 4.0, 4.5, and 5. Receiver operating characteristics (ROC) were generated using SRA at any pH as gold standard; areas under the curve (AUCs) were determined. Discordant cases were reanalyzed to determine changes in SRA and predictors of change using multivariate regression. At pH 4.0, 41% had a positive SAP, and 34% had a positive SI. While there was sustained gain in SI positivity from acidic to more weakly acidic pH thresholds, SAP positivity was highest at pH 4.5. On ROC analysis, performance characteristics were best at pH 4.0 (AUC 0.97) for SAP, and at pH 4.5 and 5.0 (AUC 0.92-0.94) for SI. On multivariate logistic regression adjusting for age, gender, and change in AET and reflux events, only number of associated symptoms predicted change in SRA (P < 0.0001). Changing pH thresholds for reflux events augments SRA by increasing reflux events associated with existing symptoms, while symptom recording remains the principal determinant of SRA.

Distal mean nocturnal baseline impedance on pH-impedance monitoring predicts reflux burden and symptomatic outcome in gastro-oesophageal reflux disease

BACKGROUND

Mean nocturnal baseline impedance (MNBI), a novel pH-impedance metric, may be a surrogate marker of reflux burden.

AIM

To assess the predictive value of MNBI on symptomatic outcomes after anti-reflux therapy.

METHODS

In this prospective observational cohort study, pH-impedance studies performed over a 5-year period were reviewed. Baseline impedance was extracted from six channels at three stable nocturnal 10-min time periods, and averaged to yield MNBI. Distal and proximal oesophageal MNBI values were calculated by averaging MNBI values at 3, 5, 7 and 9 cm, and 15 and 17 cm respectively. Symptomatic outcomes were measured as changes in global symptom severity (GSS, rated on 100-mm visual analogue scales) on prospective follow-up after medical or surgical anti-reflux therapy. Univariate and multivariate analyses assessed the predictive value of MNBI on symptomatic outcomes.

RESULTS

Of 266 patients, 135 (50.8%) were tested off proton pump inhibitor (PPI) therapy and formed the study cohort (52.1 ± 1.1 years, 63.7% F). The 59 with elevated acid exposure time (AET) had lower composite and distal MNBI values than those with physiological AET (P < 0.0001), but similar proximal MNBI (P = 0.62). Linear AET negatively correlated with distal MNBI, both individually and collectively (Pearson's r = -0.5, P < 0.001), but not proximal MNBI (Pearson's r = 0, P = 0.72). After prospective follow-up (94 patients were followed up for 3.1 ± 0.2 years), univariate and multivariate regression models showed that distal MNBI, but not proximal MNBI, was independently predictive of linear GSS improvement.

CONCLUSIONS

Distal oesophageal MNBI negatively correlates with AET and, when assessed off PPI therapy, is independently predictive of symptomatic improvement following anti-reflux therapy.

Interrogation of esophagogastric junction barrier function using the esophagogastric junction contractile integral: an observational cohort study

The esophagogastric junction contractile integral (EGJ-CI), designed similar to distal contractile integral (DCI), has been proposed as a metric to evaluate EGJ barrier function. We determined normative values and evaluated EGJ-CI in predicting esophageal acid exposure time (AET) and symptomatic outcome in this observational cohort study. High-resolution manometry (HRM) studies were reviewed in 188 patients (55.2 ± 0.9 years, 64% female) undergoing ambulatory pH monitoring off therapy. Dominant symptoms and global symptom severity (GSS) were determined on questionnaires initially and upon follow-up. EGJ-CI was measured using the DCI tool placed across the EGJ and compared to normal controls (n = 21, 27.6 ± 0.6 years, 52% female). EGJ-CI was calculated both for a single respiratory cycle (SRC, in mmHg.cm.s) and corrected for respiratory cycle (CRC, mmHg.cm). Univariate and multivariate analyses determined the predictive potential of EGJ-CI in terms of AET and post-therapy GSS at follow-up, controlling for medical versus surgical therapy. Mean EGJ-CI values were significantly lower when AET was abnormal; EGJ-CI/SRC and EGJ-CI/CRC were 86% concordant (r = 0.84). Using receiver operating characteristic analysis, values below 121.8 mmHg.cm.s (EGJ-CI/SRC) and 39.3 mmHg.cm (EGJ-CI/CRC) predicted abnormal AET best (sensitivity 0.61 and 0.65, specificity 0.61 and 0.57, respectively). On univariate and multivariate analysis, the EGJ-CI discriminated normal from abnormal AET better than conventional LES parameters (P ≤ 0.02). After 2.7 ± 0.1 years follow-up, EGJ-CI below identified thresholds predicted better symptom response to antireflux surgery compared to medical therapy (P = 0.009). EGJ-CI is a novel HRM metric that has potential to complement or replace currently used basal LES and EGJ parameters.

Achalasia: new perspectives on an old disease

Achalasia is defined by esophageal outflow obstruction from abnormal relaxation of the lower esophageal sphincter (LES) due to deranged inhibitory control. In genetically predisposed individuals, an autoimmune response to an unknown inciting agent, perhaps a viral infection, results in inflammation and sometimes loss of myenteric plexus ganglia and neurons. The net result is varying degrees of inhibitory dysfunction, at times associated with imbalanced and exaggerated excitatory function, with manometrically distinct achalasia phenotypes on high resolution manometry. There is new evidence in the current issue of this Journal suggesting that type 1 achalasia, with esophageal outflow obstruction and absent esophageal body contractility, is an end-stage phenotype from progression of type 2 achalasia, which is characterized by panesophageal compartmentalization of pressure in the untreated patient, and partial recovery of peristalsis after treatment. Esophageal outflow obstruction with premature peristalsis (type 3 achalasia) or intact peristalsis may result from plexitis in the myenteric plexus but can also be encountered in other settings including chronic opioid medication usage and structural processes at the esophagogastric junction and distally. In most instances when idiopathic esophageal outflow obstruction is confirmed, some form of pharmacologic manipulation or disruption of the LES provides durable symptom relief. This review will focus on current understanding of pathophysiology, diagnosis, and principles of management of achalasia in light of emerging literature on the topic.

The Pathogenesis and Management of Achalasia: Current Status and Future Directions

Achalasia is an esophageal motility disorder that is commonly misdiagnosed initially as gastroesophageal reflux disease. Patients with achalasia often complain of dysphagia with solids and liquids but may focus on regurgitation as the primary symptom, leading to initial misdiagnosis. Diagnostic tests for achalasia include esophageal motility testing, esophagogastroduodenoscopy and barium swallow. These tests play a complimentary role in establishing the diagnosis of suspected achalasia. High-resolution manometry has now identified three subtypes of achalasia, with therapeutic implications. Pneumatic dilation and surgical myotomy are the only definitive treatment options for patients with achalasia who can undergo surgery. Botulinum toxin injection into the lower esophageal sphincter should be reserved for those who cannot undergo definitive therapy. Close follow-up is paramount because many patients will have a recurrence of symptoms and require repeat treatment.

Cameron lesions in patients with hiatal hernias: prevalence, presentation, and treatment outcome

Cameron lesions, as defined by erosions and ulcerations at the diaphragmatic hiatus, are found in the setting of gastrointestinal (GI) bleeding in patients with a hiatus hernia (HH). The study aim was to determine the epidemiology and clinical manifestations of Cameron lesions. We performed a retrospective cohort study evaluating consecutive patients undergoing upper endoscopy over a 2-year period. Endoscopy reports were systematically reviewed to determine the presence or absence of Cameron lesions and HH. Inpatient and outpatient records were reviewed to determine prevalence, risk factors, and outcome of medical treatment of Cameron lesions. Of 8260 upper endoscopic examinations, 1306 (20.2%) reported an HH. When categorized by size, 65.6% of HH were small (<3 cm), 23.0% moderate (3-4.9 cm), and 11.4% were large (≥5 cm). Of these, 43 patients (mean age 65.2 years, 49% female) had Cameron lesions, with a prevalence of 3.3% in the presence of HH. Prevalence was highest with large HH (12.8%). On univariate analysis, large HH, frequent non-steroidal anti-inflammatory drug (NSAID) use, GI bleeding (both occult and overt), and nadir hemoglobin level were significantly greater with Cameron lesions compared with HH without Cameron lesions (P ≤ 0.03). Large HH size and NSAID use were identified as independent risk factors for Cameron lesions on multivariate logistic regression analysis. Cameron lesions are more prevalent in the setting of large HH and NSAID use, can be associated with GI bleeding, and can respond to medical management.

High-resolution anorectal manometry in newborns: normative values and diagnostic utility in Hirschsprung disease

BACKGROUND

Conventional methods of screening for Hirschsprung disease (HD) in newborns (barium enema, BE; anorectal manometry, ARM; rectal suction biopsy, RSB) have limitations and/or are invasive. High-resolution anorectal manometry (HR-ARM) is a minimally invasive technique that has potential to overcome most of these limitations, but normative data and performance characteristics have not been reported in newborns. The aims of our study were to assess anorectal sphincter metrics including resting pressure (RP), anal canal length (ACL), and rectoanal inhibitory reflex (RAIR) in healthy and asymptomatic newborns, and to explore the role of HR-ARM in the diagnosis of HD using these normal parameters.

METHODS

All procedures were performed using solid state HR-ARM equipment (Medical Measurement Systems, Enchede, The Netherland) by a single operator. In the first phase, 180 asymptomatic newborns (term newborns 95, preterm newborns 85) were studied, and anal RP, ACL, and RAIR were measured. In the second phase, 16 newborns with clinical manifestations of HD were studied (9 of whom had histopathologic confirmation), and parameters compared to asymptomatic newborns.

KEY RESULTS

Normative RP values were higher in term newborns compared with preterm newborns (p < 0.05), and correlated with age. Progressive maturation of the anal sphincter was evident with chronologic age, both in preterm and term newborns. RAIR was present in all normal subjects. Using absent RAIR as indicative of HD, HR-ARM had a sensitivity 89% and specificity of 83% compared to RSB; these performance characteristics were better than BE (sensitivity 78%, specificity 17%), with significantly higher diagnostic accuracy (80% vs 53%, respectively, p = 0.009).

CONCLUSIONS & INFERENCES

Anorectal sphincter pressure progressively matures with incremental increase in RP during the first months of life. HR-ARM is an effective and safe method that complements the diagnosis of HD in newborns.

Inter-observer agreement for diagnostic classification of esophageal motility disorders defined in high-resolution manometry

High-resolution esophageal manometry (HRM) is a recent development used in the evaluation of esophageal function. Our aim was to assess the inter-observer agreement for diagnosis of esophageal motility disorders using this technology. Practitioners registered on the HRM Working Group website were invited to review and classify (i) 147 individual water swallows and (ii) 40 diagnostic studies comprising 10 swallows using a drop-down menu that followed the Chicago Classification system. Data were presented using a standardized format with pressure contours without a summary of HRM metrics. The sequence of swallows was fixed for each user but randomized between users to avoid sequence bias. Participants were blinded to other entries. (i) Individual swallows were assessed by 18 practitioners (13 institutions). Consensus agreement (≤ 2/18 dissenters) was present for most cases of normal peristalsis and achalasia but not for cases of peristaltic dysmotility. (ii) Diagnostic studies were assessed by 36 practitioners (28 institutions). Overall inter-observer agreement was 'moderate' (kappa 0.51) being 'substantial' (kappa > 0.7) for achalasia type I/II and no lower than 'fair-moderate' (kappa >0.34) for any diagnosis. Overall agreement was somewhat higher among those that had performed >400 studies (n = 9; kappa 0.55) and 'substantial' among experts involved in development of the Chicago Classification system (n = 4; kappa 0.66). This prospective, randomized, and blinded study reports an acceptable level of inter-observer agreement for HRM diagnoses across the full spectrum of esophageal motility disorders for a large group of clinicians working in a range of medical institutions. Suboptimal agreement for diagnosis of peristaltic motility disorders highlights contribution of objective HRM metrics.

The impact of psychiatric and extraintestinal comorbidity on quality of life and bowel symptom burden in functional GI disorders

BACKGROUND

Functional gastrointestinal disorders (FGID) patients report poor health-related quality of life (HRQOL) and experience high rates of psychiatric and extraintestinal functional disorder (EIFD) comorbidity. The independent influence of these comorbidities on HRQOL and symptom burden remains unknown. We sought to determine whether FGID with mood or EIFD comorbidity have poorer HRQOL and greater GI symptom burdens; to determine the influence of comorbidities on HRQOL in FGID independent of bowel symptoms.

METHODS

Subjects reported on comorbidities (anxiety, depression, somatization, EIFD), FGID criteria (irritable bowel syndrome, IBS; functional dyspepsia, FD) using ROME III Research questionnaire, GI symptom burden, and HRQOL. Differences in measures were assessed between subjects with and without ROME III criteria. Multiple regression determined the relative contribution of comorbidities to HRQOL, and mediation analysis explored whether comorbidity influences HRQOL.

KEY RESULTS

In a cohort of 912 GI outpatients (47.2 ± 1.5 years, 75.8% female), 606 (66.4%) met Rome III IBS and/or FD criteria. Comorbidities were common in FGID (≥1 in 77.4%), leading to lower HRQOL and greater GI symptom burden (each p < 0.05). Poorer HRQOL was predicted by both psychiatric and EIFD comorbidity (each p < 0.05) independent of GI symptoms (p < 0.001). Comorbidities together exerted a greater effect on predicted variation in HRQOL (70.9%) relative to GI symptoms (26.5%).

CONCLUSIONS & INFERENCES

Psychiatric and EIFD comorbidities are common in FGID, decrease HRQOL and are associated with greater GI symptom burdens; these factors were stronger predictors of HRQOL than GI symptoms in FGID patients.

The impact of opiate pain medications and psychoactive drugs on the quality of colon preparation in outpatient colonoscopy

BACKGROUND

Suboptimal colon preparation is a significant barrier to quality colonoscopy. The impact of pharmacologic agents associated with gastrointestinal dysmotility on quality of colon preparation has not been well characterized.

AIMS

Evaluate impact of opiate pain medication and psychoactive medications on colon preparation quality in outpatients undergoing colonoscopy.

METHODS

Outpatients undergoing colonoscopy at a single medical centre during a 6-month period were retrospectively identified. Demographics, clinical characteristics and pharmacy records were extracted from electronic medical records. Colon preparation adequacy was evaluated using a validated composite colon preparation score.

RESULTS

2600 patients (57.3 ± 12.9 years, 57% female) met the inclusion and exclusion criteria. 223 (8.6%) patients were regularly using opioids, 92 antipsychotics, 83 tricyclic antidepressants and 421 non-tricyclic antidepressants. Opioid use was associated with inadequate colon preparation both with low dose (OR = 1.4, 95%CI 1.0-2.1, p = 0.05) and high dose opioid users (OR = 1.7, 95%CI 1.1-2.9, p = 0.039) in a dose dependent manner. Other significant predictors of inadequate colon preparation included use of tricyclics (OR = 1.9, 95%CI 1.1-3.0, p = 0.012), non-tricyclic antidepressants (OR = 1.5, 95%CI 1.1-2.0, p = 0.013), and antipsychotic medications (OR = 2.2, 95%CI 1.4-3.4, p = 0.001).

CONCLUSIONS

Opiate pain medication use independently predicts inadequate quality colon preparation in a dose dependent fashion; furthermore psychoactive medications have even more prominent effects and further potentiates the negative impact of opiates with concurrent use.

Esophageal motor disease and reflux patterns in patients with advanced pulmonary disease undergoing lung transplant evaluation

BACKGROUND

Advanced pulmonary disorders are linked to esophageal hypomotility and reflux disease. However, characterization of esophageal function using high resolution manometry (HRM) and ambulatory pH monitoring, segregation by pulmonary pathology, and comparison to traditional reflux disease are all limited in the literature.

METHODS

Over a 4 year period, 73 patients (55.2 ± 1.3 years, 44F) were identified who underwent esophageal function testing as part of lung transplant evaluation for advanced pulmonary disease (interstitial lung disease, ILD = 47, obstructive lung disease, OLD = 24, other = 2). Proportions of patients with motor dysfunction (≥ 80% failed sequences = severe hypomotility) and/or abnormal reflux parameters (acid exposure time, AET ≥ 4%) were determined, and compared to a cohort of 1081 patients (48.4 ± 0.4 years, 613F) referred for esophageal function testing prior to antireflux surgery (ARS).

KEY RESULTS

The proportion of esophageal body hypomotility was significantly higher within advanced pulmonary disease categories (35.6%), particularly ILD (44.7%), compared to ARS patients (12.1%, P < 0.0001). Abnormal AET was noted in 56.5%, and was similar between ILD and OLD, but less frequent than in the ARS group (P = 0.04). Post-transplant chronic rejection trended towards association with pretransplant elevated AET in OLD (P = 0.08) but not ILD. Mortality was not predicted by esophageal motor pattern or reflux evidence.

CONCLUSIONS & INFERENCES

Interstitial lung disease has a highly significant association with esophageal body hypomotility. Consequently, prevalence of abnormal esophageal acid exposure is high, but implications for post lung transplant chronic rejection remain unclear.

Symptomatic diffuse esophageal spasm as a major ictal manifestation of post-traumatic epilepsy: a case report

Post-traumatic epilepsy (PTE) can create diagnostic confusion when typical epileptic seizures are not manifest. Abdominal symptoms as a manifestation of PTE are rare in this setting. We present a 43-year-old female with paroxysmal chest and abdominal pain, nausea, salivation, and intermittent dysphagia. Esophageal testing demonstrated diffuse esophageal spasm, but smooth muscle relaxants provided no relief. Finally, after history revealed that a motor vehicle accident temporally preceded symptom onset, video electroencephalography confirmed PTE. Therapy with anti-epileptic drug completely resolved symptoms, and the esophageal motor pattern normalized. We speculate that abnormal epileptiform discharges from the seizure focus altered cerebral input to intrinsic esophageal innervation, resulting in inhibitory dysfunction and a picture resembling diffuse esophageal spasm. This is the first report of symptomatic esophageal spasm as a major ictal manifestation of PTE.

Evaluation of esophageal motor function in clinical practice

Esophageal motor function is highly coordinated between central and enteric nervous systems and the esophageal musculature, which consists of proximal skeletal and distal smooth muscle in three functional regions, the upper and lower esophageal sphincters, and the esophageal body. While upper endoscopy is useful in evaluating for structural disorders of the esophagus, barium esophagography, radionuclide transit studies, and esophageal intraluminal impedance evaluate esophageal transit and partially assess motor function. However, esophageal manometry is the test of choice for the evaluation of esophageal motor function. In recent years, high-resolution manometry (HRM) has streamlined the process of acquisition and display of esophageal pressure data, while uncovering hitherto unrecognized esophageal physiologic mechanisms and pathophysiologic patterns. New algorithms have been devised for analysis and reporting of esophageal pressure topography from HRM. The clinical value of HRM extends to the pediatric population, and complements preoperative evaluation prior to foregut surgery. Provocative maneuvers during HRM may add to the assessment of esophageal motor function. The addition of impedance to HRM provides bolus transit data, but impact on clinical management remains unclear. Emerging techniques such as 3-D HRM and impedance planimetry show promise in the assessment of esophageal sphincter function and esophageal biomechanics.

Multiple rapid swallow responses segregate achalasia subtypes on high-resolution manometry

BACKGROUND

Multiple rapid swallows (MRS) inhibit esophageal peristalsis and lower esophageal sphincter (LES) tone; a rebound excitatory response then results in an exaggerated peristaltic sequence. Multiple rapid swallows responses are dependent on intact inhibitory and excitatory neural function and could vary by subtype in achalasia spectrum disorders.

METHODS

Consecutive subjects with incomplete LES relaxation on high-resolution manometry (HRM) (Sierra Scientific, Los Angeles, CA, USA) in the absence of mechanical obstruction were prospectively identified. Achalasia spectrum disorders were classified and HRM plots reviewed according to Chicago criteria. Esophageal peristaltic performance and LES function were assessed after 10 wet swallows and MRS (five 2 mL water swallows 2-3 s apart). Findings were compared with 18 healthy controls (28.5 ± 0.6 years, 44% women).

KEY RESULTS

A total of 46 subjects (57.1 ± 2.1 years, 52.2% women) met inclusion criteria. There was complete failure of peristalsis with MRS in all subjects with achalasia subtypes 1 and 2. In contrast, 80% of achalasia subtype 3 and incomplete LES relaxation (EGJ outflow obstruction) with preserved esophageal body peristalsis had a contractile response to MRS (P < 0.001 compared with subtypes 1 and 2); controls demonstrated 94.4% peristalsis. Percent decrease in LES residual pressure during MRS (compared to wet swallows) segregated achalasia subtypes; those with aperistalsis (subtypes 1 and 2) had a lesser decline (22.6%) compared to those with retained esophageal body peristalsis (40.5%) and controls (51.3%, P < 0.001 across groups).

CONCLUSIONS & INFERENCES

Multiple rapid swallow responses segregate achalasia spectrum disorders into two patterns differentiated by presence or absence of esophageal body contraction response to wet swallows. These findings support subtyping of achalasia, with pathophysiologic implications.

Utilization of wireless pH monitoring technologies: a summary of the proceedings from the esophageal diagnostic working group

Gastroesophageal reflux disease (GERD) can be difficult to diagnose - symptoms alone are often not enough, and thus, objective testing is often required. GERD is a manifestation of pathologic levels of reflux into the esophagus of acidic, nonacidic, and/or bilious gastric content. However, in our current evidence-based knowledge approach, we only have reasonable outcome data in regards to acid reflux, as this particular type of refluxate predictably causes symptoms and mucosal damage, which improves with medical or surgical therapy. While there are data suggesting that nonacid reflux may be responsible for ongoing symptoms despite acid suppression in some patients, outcome data about this issue are limited. Therefore, this working group believes that it is essential to confirm the presence of acid reflux in patients with 'refractory' GERD symptoms or extraesophageal symptoms thought to be caused by gastroesophageal reflux before an escalation of antireflux therapy is considered. If patients do not have pathologic acid reflux off antisecretory therapy, they are unlikely to have clinically significant nonacid or bile reflux. Patients who do not have pathologic acid gastroesophageal reflux parameters on ambulatory pH monitoring then: (i) could attempt to discontinue antisecretory medications like proton pump inhibitors and H2-receptor antagonists (which are expensive and which carry risks - i.e. C. diff, etc.); (ii) may undergo further evaluation for other causes of their esophageal symptoms (e.g. functional heartburn or chest pain, eosinophilic esophagitis, gastroparesis, achalasia, other esophageal motor disorders); and (iii) can be referred to an ear, nose, and throat/pulmonary/allergy physician for assessment of non-GERD causes of their extraesophageal symptoms.

Fragmented esophageal smooth muscle contraction segments on high resolution manometry: a marker of esophageal hypomotility

BACKGROUND

Esophageal peristalsis consists of a chain of contracting striated and smooth muscle segments on high resolution manometry (HRM). We compared smooth muscle contraction segments in symptomatic subjects with reflux disease to healthy controls.

METHODS

High resolution manometry Clouse plots were analyzed in 110 subjects with reflux disease (50 ± 1.4 years, 51.5% women) and 15 controls (27 ± 2.1 years, 60.0% women). Using the 30 mmHg isobaric contour tool, sequences were designated fragmented if either smooth muscle contraction segment was absent or if the two smooth muscle segments were separated by a pressure trough, and failed if both smooth muscle contraction segments were absent. The discriminative value of contraction segment analysis was assessed.

KEY RESULTS

A total of 1115 swallows were analyzed (reflux group: 965, controls: 150). Reflux subjects had lower peak and averaged contraction amplitudes compared with controls (P < 0.0001 for all comparisons). Fragmented sequences followed 18.4% wet swallows in the reflux group, compared with 7.5% in controls (P < 0.0001), and were seen more frequently than failed sequences (7.9% and 2.5%, respectively). Using a threshold of 30% in individual subjects, a composite of failed and/or fragmented sequences was effective in segregating reflux subjects from control subjects (P = 0.04).

CONCLUSIONS & INFERENCES

Evaluation of smooth muscle contraction segments adds value to HRM analysis. Specifically, fragmented smooth muscle contraction segments may be a marker of esophageal hypomotility.

Assessment of concordance of symptom reflux association tests in ambulatory pH monitoring

BACKGROUND

Both simple proportions and statistical tests are utilised for symptom-reflux association. We systematically compared three such tests in a clinical setting.

AIM

To compare the three commonly used symptom reflux association tests in a large cohort of patients undergoing ambulatory pH monitoring for the evaluation of oesophageal symptoms.

METHODS

Ambulatory pH data from 772 symptomatic subjects (49.1 ± 0.5 years; 479 F) tested off therapy were assessed for acid exposure time (AET, elevated when pH <4 for ≥4%), symptom index (SI, ≥50% when positive), and symptom association probability (SAP) and Ghillebert probability estimate (GPE, P < 0.05 when positive). Test concordance and discordance were individually assessed; discordance between statistical tests was minor if one had P < 0.1 while the other was positive. Logistic regression determined independent predictors of test discordance.

RESULTS

The SAP, GPE and SI were positive in 42.7%, 39.3% and 33.9% respectively. GPE performed extremely well compared to SAP (sensitivity 0.95, specificity 0.91), with major discordance in only 2.8%. Positive concordance was significantly higher when AET was abnormal. GPE underestimated symptom association compared to SAP, whereas SAP was subject to symptom over-counting in 33.3% of discordant cases. GPE-SAP discordance was associated with higher AET (7.5% vs. 5.1%) and more symptoms (19.3 vs. 10.7, P > 0.001 for each comparison with concordant tests); both remained significant on logistic regression analysis (P ≤ 0.003). SI was discordant with SAP when symptoms were extremely frequent (median 19, IQR 10-32) or limited (median 1, IQR 1-2), and concordant when median 6 symptoms (IQR 3-12) were recorded.

CONCLUSIONS

The GPE can be used interchangeably with SAP in symptom reflux association. SI has uncertain value with very high and very low symptom counts.

Assessment of concordance of symptom reflux association tests in ambulatory pH monitoring

BACKGROUND

Both simple proportions and statistical tests are utilised for symptom-reflux association. We systematically compared three such tests in a clinical setting.

AIM

To compare the three commonly used symptom reflux association tests in a large cohort of patients undergoing ambulatory pH monitoring for the evaluation of oesophageal symptoms.

METHODS

Ambulatory pH data from 772 symptomatic subjects (49.1 ± 0.5 years; 479 F) tested off therapy were assessed for acid exposure time (AET, elevated when pH <4 for ≥4%), symptom index (SI, ≥50% when positive), and symptom association probability (SAP) and Ghillebert probability estimate (GPE, P < 0.05 when positive). Test concordance and discordance were individually assessed; discordance between statistical tests was minor if one had P < 0.1 while the other was positive. Logistic regression determined independent predictors of test discordance.

RESULTS

The SAP, GPE and SI were positive in 42.7%, 39.3% and 33.9% respectively. GPE performed extremely well compared to SAP (sensitivity 0.95, specificity 0.91), with major discordance in only 2.8%. Positive concordance was significantly higher when AET was abnormal. GPE underestimated symptom association compared to SAP, whereas SAP was subject to symptom over-counting in 33.3% of discordant cases. GPE-SAP discordance was associated with higher AET (7.5% vs. 5.1%) and more symptoms (19.3 vs. 10.7, P > 0.001 for each comparison with concordant tests); both remained significant on logistic regression analysis (P ≤ 0.003). SI was discordant with SAP when symptoms were extremely frequent (median 19, IQR 10-32) or limited (median 1, IQR 1-2), and concordant when median 6 symptoms (IQR 3-12) were recorded.

CONCLUSIONS

The GPE can be used interchangeably with SAP in symptom reflux association. SI has uncertain value with very high and very low symptom counts.

High-resolution manometric characteristics help differentiate types of distal esophageal obstruction in patients with peristalsis

BACKGROUND

High-resolution manometry (HRM) can identify obstructive motor features at the esophagogastric junction and abnormalities in esophageal bolus transit. We sought to determine if HRM patterns can differentiate functional from organic mechanical lower esophageal sphincter (LES) obstruction.

METHODS

Segmental characteristics of peristalsis were examined using HRM in symptomatic subjects with elevated postdeglutitive residual pressure gradients across the LES (≥5mmHg). Sixteen consecutive patients with non-achalasic mechanical fixed obstruction were compared with 13 patients with elevated pressure gradients yet no mechanical obstruction and 14 asymptomatic controls. Pressure volumes were determined in mmHg cm s for peristaltic segments defined on HRM Clouse plots using an on-screen pressure volume measurement tool.

KEY RESULTS

Residual pressure gradients were similarly elevated in both patient groups. A visually conspicuous and distinctive shift in the proportionate pressure strengths of the second and third peristaltic segments was apparent across groups. Whereas the ratios of peak pressures and pressure volumes between second and third segments approached 1 in controls (0.92, 0.98), pressures shifted to the second segment in mechanical obstruction (peak pressure ratio: 1.2±0.4; pressure volume ratio: 1.8±0.9) and to the third segment in functional obstruction (peak ratio: 0.7±0.2; volume ratio: 0.5±0.2; P<0.02 for any comparison of either group with controls). A threshold volume ratio of 1.0 correctly segregated 93% of obstruction (P<0.0001); visual pattern inspection was equally effective.

CONCLUSIONS & INFERENCES

When elevated residual pressure gradients are present in non-achalasic patients, topographic characteristics of peristalsis can differentiate fixed mechanical obstruction from functional obstruction.

Botulinum toxin injection in dysphagia syndromes with preserved esophageal peristalsis and incomplete lower esophageal sphincter relaxation

BACKGROUND

Botulinum toxin injection into the lower esophageal sphincter (LES) treats dysphagia syndromes with preserved peristalsis and incomplete LES relaxation (LESR). We evaluated clinical and esophageal motor characteristics predicting response, and compared duration of efficacy to similarly treated achalasia patients.

METHODS

Thirty-six subjects (59 ± 2.2 years, 19F/17M) with incomplete LESR on high resolution manometry (HRM) treated with botulinum toxin injection were identified. Individual and composite symptom indices were calculated, and HRM characteristics extracted. Symptom resolution for 6 months was a primary outcome measure, and repeat botulinum toxin injection, dysphagia recurrence or employment of alternate therapeutic approaches were secondary outcome measures. Duration of response was compared using Kaplan-Meier survival curves to a historical cohort of similarly treated achalasia subjects.

KEY RESULTS

Response lasted a mean of 12.8 ± 2.3 months. Symptom relief for >6 months was seen in 58.3%; short (<6 months) response was associated with younger age, higher chest pain index, and esophageal body spastic features (P ≤ 0.04). On multivariate logistic regression, chest pain, younger age and contraction amplitudes >180 mmHg independently predicted <6 months relief (P < 0.05 for each). On survival analysis, relief with a single injection extended to 1 year in 54.8% and 1.5 years in 49.8%, statistically equivalent to that reported by 42 similarly treated achalasia subjects (59 ± 3.2 years, 24F/18M). Symptom relief was more prolonged compared to achalasia when repeat injections were performed on demand (P = 0.003).

CONCLUSIONS & INFERENCES

Botulinum toxin injections can provide lasting symptom relief in dysphagia syndromes with incomplete LESR. Prominent perceptive symptoms and non-specific spastic features may predict shorter relief.