DeVault, Kenneth R.

AbstractBackgroundProximal reflux and incomplete transit of boluses swallowed are risk factors for obstructive chronic lung allograft dysfunction (o‐CLAD) post‐lung transplantation (LTx). Likewise, so is esophagogastric junction outflow obstruction (EGJOO), but not hypo‐contractility, when diagnosed using Chicago Classification (CC) v3.0. Given, peristaltic breaks as defined using CCv2.0 can prolong esophageal clearance, both swallowed and refluxed, but which are deemed within normality using CCv3.0, our aim was to determine whether hypo‐contractility as diagnosed using CCv2.0, influences the association with reflux, along with its clearance, and that of boluses swallowed, and thus its association to allograft failure.MethodsEsophageal motility abnormalities were classified using CC v3.0 and v2.0 in 50 patients post‐LTx (26 female, 55 years (20‐73 years)).ResultsReclassification from CCv3.0 to v2.0 resulted in 7 patients with normal motility being reclassified to hypo‐contractility (n = 6) or hyper‐contractility (n = 1); 2 patients with hypo‐contractility to normal motility; and 3 patients with EGJOO without hyper‐contractility to EGJOO with hyper‐contractility. The main consequence of reclassification was that the sub‐group exhibiting hypo‐contractility became more likely to have abnormal numbers of reflux events (P = .025) and incomplete bolus transit (P = .002) than those with normal motility using CCv2.0; associations not seen using CCv3.0. Irrespective of CC used only patients with EGJOO appeared more likely to develop o‐CLAD than those with normal motility (P < .05).ConclusionsIrrespective of CC used, o‐CLAD appears linked to EGJOO. CCv2.0 however, accentuates the increased reflux and incomplete bolus transit associated with hypo‐contractility post‐LTx, suggesting that these motor abnormalities, though considered minor, may be of importance after lung transplant.

We sought to determine the esophageal sensory function in patients with a C6 or C7 spinal cord injury. A balloon was repetitively distended 10 cm above the lower esophageal sphincter in five patients and nine normal control subjects. Sensation was reported on a scale from 0 to 2 with progressive distension to pain threshold (level 2). Cortical responses were recorded from midline scalp electrodes. Blinded determinations of quality and reproducibility of the potentials were performed. All subjects experienced sensation with esophageal balloon distension. Volumes to sensation showed a trend toward a higher sensory threshold in patients but were significant only for first sensation, not pain. In all subjects, a triphasic evoked potential response consisting of a negative-positive-negative complex was noted with distension but not with sham distension. Characteristics (amplitude, latency, reproducibility, and quality) of the evoked potentials were not different in patient and control groups. These data suggest sensory pathways from the distal esophagus are intact in patients with a C6 or C7 spinal cord injury.

AbstractBackgroundGastroesophageal reflux plays an important role in chronic cough (CC). Whether disturbed esophageal motility contributes to increased esophageal reflux exposure or interferes with swallowed bolus clearance is unclear. This study used high resolution esophageal manometry and impedance (HRIM) together with Chicago Classification, and 24‐h impedance pH (MII/pH) to address these questions in patients with CC compared with heartburn (HB).MethodsA retrospective review of 32 patients with CC (mean age 57 [95% CI: 52–62] years) and 32 patients with symptoms of HB (55 [52–62] years) referred for HRIM and MII/pH between September 2012 and September 2013 was undertaken.Key ResultsWeak peristalsis with large breaks (WPLBs) was observed in 34% of CC patients compared with only 12% of HB patients (p = 0.027). Pathological acid exposure time (AET) was identified in 81% of CC patients with WPLBs compared with 29% without (p = 0.011). Increased AET was associated with prolonged clearance time of refluxed events (p = 0.006) rather than increased number of events. AET correlated with the percentage of peristaltic events with large breaks in CC (ρ = 0.467, p = 0.007). Similar data were obtained for total bolus (acid and non‐acid) exposure time. Only one of the CC patients with WPLBs exhibited complete bolus transit (CBT) on swallowing compared with 81% without WPLBs (p < 0.001). Moreover, the percentage of peristaltic events associated with CBT negatively correlated with the percentage of peristaltic events with large breaks (r = −0.653, p < 0.001) in CC.Conclusions & InferencesOne‐third of CC patients exhibit WPLBs, which directly impacts on clearance of refluxed events and bolus's swallowed. These observations may have important implications for esophageal‐bronchial interaction in CC.

The following on achalasia and disorders of the esophageal body includes commentaries on controversies regarding whether patients with complete lower esophageal sphincter (LES) relaxation can be considered to exhibit early achalasia; the roles of different mucle components of the LES in achalasia; sensory neural pathways impaired in achalasia; indications for peroral endoscopic myotomy and advantages of the technique over laparoscopic and thorascopic myotomy; factors contributing to the success of surgical therapy for achalasia; modifications to the classification of esophageal body primary motility disorders in the advent of high‐resolution manometry (HRM); analysis of the LES in differentiating between achalasia and diffuse esophageal spasm (DES); and appropriate treatment for DES, nutcracker esophagus (NE), and hypertensive LES (HTLES).

Abstract Background: In patients with Barrett's esophagus, chronic reflux injury and inflammation are associated with esophageal adenocarcinoma, one of the most rapidly increasing lethal cancers. Epidemiological and preclinical studies support decreased risk of esophageal adenocarcinoma with NSAID use. Gastroesophageal refluxate contents can promote carcinogenesis in Barrett's metaplasia by activating AKT, which up regulates COX-2 expression and prostaglandin biosynthesis. We recently noted that neoplastic transformation in Barrett's esophagus is associated with increased AKT expression, particularly isoform AKT1. The AIM of this study is to investigate the effect of NSAID (Aspirin) use in patients with Barrett's esophagus on AKT1 expression using frozen tissue from the randomized, phase II trial of aspirin and esomeprazole for esophageal cancer chemoprevention in Barrett's esophagus patients and to assess the functional consequences of AKT1 expression in-vitro. Methods and Results: In a subset of patients (12 of 120 patients) with Barrett's esophagus who were randomized to placebo, lower dose (81 mg) or higher dose (325 mg) Aspirin for 4 weeks, both PCR and Western blot revealed marked reduction in AKT1 expression in patients who received 325 mg of Aspirin daily compared to patients who received placebo. Our in-vitro experiments support that AKT1 expression is functionally relevant to the process of carcinogenesis in Barrett's epithelial cells. Using adenovirus to induce AKT1 expression, we show that increased AKT1 expression increases Barrett's epithelial cell growth, facilitates RAS-mediated transformation of pre-neoplastic epithelial cells and promotes colony formation. Since AKT1 is known as Warburg kinase and regulates cellular glucose uptake to support aerobic glycolysis during growth de-regulation and neoplasia, we examined the uptake of fluorescent deoxyglucose analog (2-NBDG) in Barrett's epithelial cells transduced with AKT1 adenovirus. At 48 hrs, compared to control, AKT1 overexpression resulted in increased glucose uptake both by metaplastic and neoplastic Barrett's epithelial cells. Transcriptional repression of AKT1 abrogated the 2-NBDG uptake by these cells. Finally, we did pathway specific qPCRs and noted that use of Aspirin is associated with altered expression of chromatin remodelers that could down-regulate AKT1 expression. Conclusion: Collectively, our results demonstrate that Aspirin mediated down-regulation of Warburg kinase AKT1 in patients with Barrett?s esophagus is a novel mechanism for the regulation of Barrett?s epithelial cell growth. The in-depth characterization of molecular mechanisms is currently underway. This abstract is also presented as Poster A82. Citation Format: Navtej S. Buttar, Gary W. Falk, Cathrine J. DeMars, Sonia Chowdhury, Ahmed Elebiary, Anamay Sharma, Sidhartha Chaudhry, Nathan R. Foster, Katie L. Allen Ziegler, Yvonne Romero, Norman E. Marcon, Thomas Schnell, Douglas A. Corley, Prateek Sharma, Marcia R. Cruz-Correa, Chin Hur, David E. Fleischer, Amitabh Chak, Kenneth R. DeVault, David S. Weinberg, Gary Della’Zanna, Ellen Richmond, Thomas C. Smyrk, Sumithra Mandrekar, Paul J. Limburg. Aspirin mediated downregulation of Warburg kinase AKT1 in patients with Barrett's esophagus: Implications in neoplastic transformation. [abstract]. In: Proceedings of the Eleventh Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2012 Oct 16-19; Anaheim, CA. Philadelphia (PA): AACR; Cancer Prev Res 2012;5(11 Suppl):Abstract nr PR-03.

The following paper on gastroesophageal reflux disease (GERD) and Barrett's esophagus (BE) includes commentaries on defining esophageal landmarks; new techniques for evaluating upper esophageal sphincter (UES) tone; differential diagnosis of GERD, BE, and hiatal hernia (HH); the use of high‐resolution manometry for evaluation of reflux; the role of fundic relaxation in reflux; the use of 24‐h esophageal pH–impedance testing in differentiating acid from nonacid reflux and its potential inclusion in future Rome criteria; classification of endoscopic findings in GERD; the search for the cell origin that generates BE; and the relationship between BE, Barrett's carcinoma, and obesity.

SummaryBackgroundCurrent diagnostic guidelines recommend that eosinophilic oesophagitis (EoE) should be diagnosed only after GERD is excluded by a lack of response to a trial of acid suppression. There is limited information available providing outcome data about the effectiveness of this approach.AimTo examine the impact of double‐dose proton pump inhibitor (PPI) therapy on symptoms, endoscopic and histological features in patients with documented oesophageal eosinophilia consistent with EoE (≥15 eosinophils/high‐power field).MethodsSixty consecutive symptomatic patients with documented oesophageal eosinophilia received open‐label omeprazole 20 mg orally twice daily before meals for 8 weeks. Clinical, endoscopic and histological (resolution: 0–5 eosinophils/HPF, partial improvement: 5–14 eosinophils/HPF), or no improvement: (≥15 eosinophils/HPF) evaluation was repeated at the end of this period. An expert GI pathologist, unaware of the study aims, reviewed all slides.ResultsClinical improvement occurred in 43 (71.6%), endoscopic signs were reduced in 34 (61.8%) and normalised in 12 (21.8%), and histologically, 34 (56.6%) improved, while 15 (25%) obtained complete resolution. Overall, 22 patients (36.7%) obtained both complete clinical and histological remission.ConclusionsMore than 50% of patients with documented oesophageal eosinophilic infiltration in the EoE range improved when treated with a double‐dose PPI trial for 8 weeks. These findings support the published guidelines recommending a PPI trial prior to diagnosing EoE, and confirm the existence of an eosinophilic oesophageal infiltrationPPI‐responsive population.

AbstractBackgroundLow basal lower esophageal sphincter (LES) pressure and transient LES relaxations are major causes of gastroesophageal reflux disease (GERD). Pumosetrag, a novel selective partial 5HT3 receptor agonist, showed a promising effect on reducing reflux events in health. We aimed to evaluate the effect of pumosetrag on changes in reflux episodes, lower esophageal sphincter pressure (LESP), and specific symptoms in patients with GERD receiving a refluxogenic meal.MethodsPatients with GERD, who developed heartburn and/or regurgitation after ingestion of a refluxogenic meal, were randomized to 1 of 3 dose levels of pumosetrag (0.2, 0.5, or 0.8 mg) or placebo. Before and after 7 days of treatment, patients underwent manometry, intraesophageal multichannel, intraluminal impedance and pH after a standard refluxogenic meal.Key ResultsA total of 223 patients with GERD [125 (56%) women, mean (SD) age = 36 (12) years] were enrolled. No overall treatment effects were detected for the total number of reflux episodes (acidic and weakly acidic) (p > 0.5); however, significant treatment effects (p < 0.05) on the number of acid reflux episodes were observed with lower values on pumosetrag 0.2 mg (10.8 ± 1.1), 0.5 mg (9.5 ± 1.1), and 0.8 mg (9.9 ± 1.1) compared with placebo (13.3 ± 1.1). Significant treatment effects (p < 0.05) were also observed for the percentage of time pH was <4, with less time for pumosetrag at 0.5 mg (10%) and 0.8 mg (10%) compared with placebo (16%).Conclusions & InferencesIn GERD, the partial 5HT3 agonist pumosetrag significantly reduced the rate of acid reflux events but did not result in a significant change in LESP or symptomatic improvement over a 1‐week treatment period.