Weight loss in achalasia is determined by its phenotype

Patients with achalasia present with dysphagia, regurgitation, and varying degrees of weight loss. However, despite it being a disorder of the lower esophageal sphincter with functional obstruction in all patients, it is unclear why certain patients lose significantly more weight compared to others. The aims of this study are to assess demographic, clinical, and manometric characteristics of a large cohort of patients with achalasia to determine potential correlates of weight loss in this population. Patients with diagnosis of achalasia referred to our center between 2009 and 2016 were evaluated. Demographic and physiologic tests between those with and without weight loss were compared. The cohort of patients with initial self-reported weight loss were studied to determine change in weight after intervention (pneumatic dilation or myotomy). The Kruskal-Wallis test was used for comparison of continuous variables between groups and Pearson's χ2 test was used for comparison of categorical variables between groups. 138 patients with achalasia were evaluated. 35 patients were excluded due to lack of manometric data and 3 from lack of documented weight resulting in the study population of 100 patients with achalasia [51% male, median age: 56 years]. Weight loss was reported in 51/100 (51%) patients. BMI was lower in patients who reported weight loss (25 vs. 31, P < 0.001) with a median weight loss of 28 lbs (14-40 lbs). There were no significant differences in age at diagnosis, gender, or symptom presentation (dysphagia, regurgitation, or chest pain) between the groups. However, more patients with type II achalasia (63%) reported weight loss as compared to other sub-types (P = 0.013). 73% of type III achalasia denied having weight loss. Patients who denied weight loss had symptoms for longer duration (24 vs. 12 months, P < 0.001) and had lower mean residual LES pressure (20 vs. 30 mmHg, P = 0.006). Postintervention 42% of patients reported no weight regain despite appropriate therapy for achalasia with median follow-up of 22 months (range: 6-90 months). Type II achalasia patients are most likely and type III achalasia are least likely to have weight loss compared to type I achalasia. Given that no other demographic/physiologic parameters predicted weight loss, the role of underlying inflammatory cascade in achalasia phenotypes deserves special attention.

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.

Symptom association probability does not reliably distinguish functional heartburn from reflux hypersensitivity

BACKGROUND

Symptom association probability (SAP) is thought to distinguish reflux hypersensitivity from functional disorders. A diagnosis of hypersensitive oesophagus (SAP-positive) indicates that gastro-oesophageal reflux disease (GERD) is the cause of continued symptoms.

AIM

To conduct an analysis of pH and symptom criteria that lead to a diagnosis of SAP-positivity METHODS: We calculated SAP for 205 patients with GERD symptoms refractory to proton pump inhibitor (PPI) therapy who underwent endoscopy with wireless pH monitoring from 2007 to 2014. Patients were divided into three groups: pH-negative with no oesophagitis (n = 45), pH-positive with no oesophagitis (n = 130), and patients with oesophagitis (n = 30). We constructed a 2 × 2 table of symptom and reflux event association and quantified the number of 2-minute intervals for each of the 2 × 2 variables that distinguished SAP-positive from SAP-negative. In a separate cohort of 58 patients who had undergone anti-reflux surgery, we evaluated the effects of pre-surgery SAP.

RESULTS

The difference in symptom association parameters that led to a diagnosis of an SAP-positive was small (2.98% in oesophagitis-positive; 1.56% in oesophagitis-negative/pH-positive; 0.48% in oesophagitis-negative/pH-negative). In the pH-negative/oesophagitis-negative group, a difference of 0.48% led to a diagnosis of hypersensitivity. There was significant variability in SAP values between day 1 and day 2 of pH testing in all groups, with the greatest in the oesophagitis-positive group, despite objective evidence for reflux (27% in oesophagitis-positive, 19% pH-positive/oesophagitis-negative, and 7% in pH-negative/oesophagitis-negative). Pre-surgery SAP was not associated with response to anti-reflux surgery.

CONCLUSION

In PPI-refractory GERD, SAP cannot accurately distinguish reflux hypersensitivity from functional oesophageal symptoms.

Economic and survival burden of dysphagia among inpatients in the United States

The inpatient burden of dysphagia has primarily been evaluated in patients with stroke. It is unclear whether dysphagia, irrespective of cause, is associated with worse clinical outcomes and higher costs compared to inpatients with similar demographic, hospital, and clinical characteristics without dysphagia. The aim of this study is to assess how a dysphagia diagnosis affects length of hospital stay (LOS), costs, discharge disposition, and in-hospital mortality among adult US inpatients. Annual and overall dysphagia prevalence, LOS, hospital charges, inpatient care costs, discharge disposition, and in-hospital mortality were measured using the AHRQ Healthcare Cost and Utilization Project (HCUP) National Inpatient Sample (2009-2013). Patients aged 45 years or older with ≤180 days of stay in hospital with and without dysphagia were included. Multivariable survey regression methods with propensity weighting were used to assess associations between dysphagia and different outcomes. Overall, 2.7 of 88 million (3.0%) adult US inpatients had a dysphagia diagnosis (50.2% male, 72.4% white, 74.6% age 65-90 years) and prevalence increased from 408,035 (2.5% of admissions) in 2009 to 656,655 (3.3%) in 2013. After inverse probability of treatment weighting adjustment, mean hospital LOS in patients with dysphagia was 8.8 days (95% CI 8.66-8.90) compared to 5.0 days (95% CI 4.97-5.05) in the non-dysphagia group (P < 0.001). Total inpatient costs were a mean $6,243 higher among those with dysphagia diagnoses ($19,244 vs. 13,001, P < 0.001). Patients with dysphagia were 33.2% more likely to be transferred to post-acute care facility (71.9% vs. 38.7%, P < 0.001) with an adjusted OR of 2.8 (95% CI 2.73-2.81, P < 0.001). Compared to non-cases, adult patients with dysphagia were 1.7 times more likely to die in the hospital (95% CI 1.67-1.74). Dysphagia affects 3.0% of all adult US inpatients (aged 45-90 years) and is associated with a significantly longer hospital length of stay, higher inpatient costs, a higher likelihood of discharge to post-acute care facility, and inpatient mortality when compared to those with similar patient, hospital size, and clinical characteristics without dysphagia. Dysphagia has a substantial health and cost burden on the US healthcare system.

Does my patient still have reflux when ppi therapy does not work?

Gastroesophageal reflux disease (GERD) is a common condition around the world. The management of this disease is less than satisfying given complexity of patient presentation and suboptimal diagnostic testing when employed for those poorly responsive to acid suppressive therapy. In this mini review, we discuss some new strategies employed for patients with suspected GERD to better understand disease pathophysiology. We compare the strategies and outline a clinically relevant approach in this difficult group of patients.

Randomized controlled trial comparing esophageal dilation to no dilation among adults with esophageal eosinophilia and dysphagia

The role of esophageal dilation in patients with esophageal eosinophilia with dysphagia remains unknown. The practice of dilation is currently based on center preferences and expert opinion. The aim of this study is to determine if, and to what extent, dysphagia improves in response to initial esophageal dilation followed by standard medical therapies. We conducted a randomized, blinded, controlled trial evaluating adult patients with dysphagia and newly diagnosed esophageal eosinophilia from 2008 to 2013. Patients were randomized to dilation or no dilation at time of endoscopy and blinded to dilation status. Endoscopic features were graded as major and minor. Subsequent to randomization and endoscopy, all patients received fluticasone and dexlansoprazole for 2 months. The primary study outcome was reduction in overall dysphagia score, assessed at 30 and 60 days post-intervention. Patients with severe strictures (less than 7-mm esophageal diameter) were excluded from the study. Thirty-one patients were randomized and completed the protocol: 17 randomized to dilation and 14 to no dilation. Both groups were similar with regard to gender, age, eosinophil density, endoscopic score, and baseline dysphagia score. The population exhibited moderate to severe dysphagia and moderate esophageal stricturing at baseline. Overall, there was a significant (P < 0.001) but similar reduction in mean dysphagia score at 30 and 60 days post-randomization compared with baseline in both groups. No significant difference in dysphagia scores between treatment groups after 30 (P = 0.93) or 60 (P = 0.21) days post-intervention was observed. Esophageal dilation did not result in additional improvement in dysphagia score compared with treatment with proton pump inhibitor and fluticasone alone. In patients with symptomatic esophageal eosinophilia without severe stricture, dilation does not appear to be a necessary initial treatment strategy.

Expression analysis of microRNA-125 in patients with polycythemia vera and essential thrombocythemia and correlation with JAK2 allele burden and laboratory findings

INTRODUCTION

The JAK2V617F mutation has emerged in recent years as a diagnostic as well as a treatment target in patients with polycythemia vera (PV) and essential thrombocythemia (ET). The disease phenotype is also influenced by other factors such as microRNA (miRNA) deregulation. The aim of this study was to investigate miR-125 expression level in these patients with those obtained from healthy control subjects and its correlation with JAK2 allele burden and laboratory findings.

METHODS

In total, forty patients with a clinical diagnosis of PV and ET were examined at the time of diagnosis. Ten healthy subjects were checked as controls. We performed JAK2 V617F allele burdens measurement and expression analysis of miR-125b-5p, miR-125b-3p, miR-125a-5p, and miR-125a-3p in leukocytes isolated from peripheral blood by quantitative real-time polymerase chain reaction.

RESULTS

MiR-125b-5p and miR-125a-5p were upregulated in both patients with PV (P = 0.00 and P = 0.003, respectively) and ET (P = 0.02 and P = 0.002, respectively). In PV group, a significant correlation was observed between miR-125a-5p and platelet counts (P = 0.01, r = 0.531). The correlation between miRNA and JAk2 allele burden was not significant.

CONCLUSION

In conclusion, our data indicate that other factors such as aberrant miR-125 expression may influence on the disease phenotype in patients with PV and ET.

An oropharyngeal pH monitoring device to evaluate patients with chronic laryngitis

BACKGROUND

Diagnostics for gastro-esophageal reflux disease (GERD) are suboptimal because of limited sensitivity. We performed in vitro and in vivo studies to systematically assess the performance characteristics of an oropharyngeal pH probe.

METHODS

In vitro studies compared the oropharyngeal probe with a standard pH catheter in liquid and aerosolized solutions, pH 1-7. The accuracy of measurements, deviation from target pH, and time to equilibrium pH were determined. Simultaneous distal esophageal pH measurements were obtained in 11 patients with GERD. Oropharyngeal and distal esophageal reflux parameters were measured for controls (n = 20), patients with GERD (n = 17), and patients with chronic laryngitis (n = 10).

KEY RESULTS

In the liquid phase, at pH 4-5, the oropharyngeal probe had less deviation from the target value than the standard catheter; deviation in the vapor phase was similar (0.4 pH units). Median (interquartile) time to reach equilibrium pH was significantly (P < 0.001) faster with the oropharyngeal than the standard probe. In comparing simultaneous distal esophageal pH characteristics, 96% of recordings with the new and standard probes were in agreement to within ± 1.0 pH unit; 71% of recordings were in agreement within ± 0.5 pH units. Patients with chronic laryngitis had significantly higher levels of oropharyngeal acid exposure at pH <4, <5, and <6, in the upright position than patients with GERD or controls (P < .001).

CONCLUSIONS & INFERENCES

Oropharyngeal pH monitoring appears to be more sensitive than traditional pH monitoring in evaluation of patients with extraesophageal reflux. It is a promising tool in evaluation of this difficult group of patients.

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.

Dilated intercellular space in chronic laryngitis and gastro-oesophageal reflux disease: at baseline and post-lansoprazole therapy

BACKGROUND

Dilation of intercellular spaces is reported to be an early morphological marker in gastro-oesophageal reflux. It remains unknown if this marker is useful in diagnosing reflux-related chronic laryngitis.

AIM

To determine histopathology and electron microscopic changes in oesophageal and laryngeal epithelium in chronic laryngitis.

METHODS

In this prospective blinded study, we enrolled 53 participants: 15 controls, 20 patients with GERD and 18 patients with chronic laryngitis. The latter two groups were subsequently treated with lansoprazole 30 mg bid for 12-weeks. Baseline and postacid suppressive therapy biopsies were obtained from distal oesophagus and laryngeal postcricoid areas. Biopsy specimens were evaluated for histopathology and dilated intercellular space changes.

RESULTS

There was no significant increase in oesophageal or laryngeal epithelium intercellular spaces among GERD or laryngitis patients compared with controls at baseline or postacid suppressive therapy. Only patients with GERD had significantly (P = 0.03) higher proportion of moderate-to-severe oesophageal spongiosis and basal cell hyperplasia, which normalized postacid suppressive therapy.

CONCLUSIONS

There was no increase in the width of intercellular spaces in the oesophagus or larynx in GERD or chronic laryngitis at baseline or postacid suppressive therapy. Our findings question the uniform presence of dilated intercellular space in patients with GERD.

Clinical trial design in adult reflux disease: a methodological workshop

BACKGROUND

The development of well-tolerated acid suppressant drugs has stimulated substantial growth in the number of trials assessing therapy options for gastro-oesophageal reflux disease (GERD).

AIM

To develop consensus statements to inform clinical trial design in adult patients with GERD.

METHODS

Draft statements were developed employing a systematic literature review. A modified Delphi process including three rounds of voting was used to reach consensus. Between voting, statements were revised based on feedback from the Working Group and additional literature reviews. The final vote was at a face-to-face meeting that included discussion time. Voting was conducted using a six-point scale.

RESULTS

At the last vote, 93% of the final 102 statements achieved consensus (defined a priori as being supported by >or=75% of the votes). The Working Group strongly supported the development of validated patient-reported outcome instruments. Symptom assessments carried out by the investigator were considered unacceptable. There was agreement that exclusion from clinical trials should be minimized to improve generalizability, that prospective evaluation ideally requires electronic timed/dated methods and that endoscopists should be blinded to patient symptom status.

CONCLUSIONS

Implementation of the consensus statements will improve the quality and comparability of trials, and make them compatible with regulatory requirements.

Extra-esophageal manifestations of gastroesophageal reflux

Gastroesophageal reflux disease (GERD) is a common medical condition affecting approximately 35-40% of the adult population in the western world. The role of GERD in causing extra-esophageal symptoms including laryngitis, asthma, cough, chest pain, and dental erosions is increasingly recognized with renewed interest among gastroenterologists and other specialists. Direct injury by mucosal contact, and vagally mediated reflex from distal esophageal acid exposure are the two possible mechanisms by which reflux-related extra-esophageal tissue injuries may occur. Several investigational techniques may be used to diagnose gastroesophageal reflux; however, because of the poor sensitivity of endoscopy and pH monitoring, and the poor specificity of laryngoscopy, empiric therapy with proton-pump inhibitors (PPI) is now considered the initial diagnostic step in patients suspected of having GERD-related symptoms. In those who improve with such therapy, it is likely that GERD may be the cause of the extra-esophageal presentation. In those who are unresponsive to such therapy, other diagnostic testing such as impedance/pH monitoring may be reasonable in order to exclude continued acid or weakly acid reflux. However, PPI-unresponsive patients usually have causes other than GERD for the extra-esophageal symptoms and signs.

Laryngeal disorders in patients with gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) is a common medical condition affecting approximately 35-40% of the adult population in the western world. Chronic laryngeal signs and symptoms associated with GERD are often referred to as reflux laryngitis or laryngopharyngeal reflux (LPR). It is estimated that up to 15% of all visits to the otolaryngology offices are because of manifestations of LPR. Injury may occur as a result of one or chronic reflux of gastroduodenal contents directly injuring the laryngeal mucosa. Since less amount of acid is required to make the injury to the larynx as compared to injury to esophagus; it is believed that intermittent exposure to small amount of gastric content can result in laryngitis. The most common presenting symptoms of LPR include hoarseness, sore throat, throat clearing, and chronic cough. The diagnosis of LPR is usually made on the basis of presenting symptoms and associated laryngeal signs including laryngeal edema and erythema. Current recommendation for management of this group of patients is empiric therapy with twice daily proton-pump inhibitors for 2 to 4 months. In majority of those who are unresponsive to such therapy other causes of laryngeal irritation is considered. Surgical fundoplication is most effective in those who are responsive to acid suppressive therapy.

Review article: the role of pH monitoring in extraoesophageal gastro-oesophageal reflux disease

Gastro-oesophageal reflux disease is associated with several extraoesophageal disease states including laryngitis, asthma, chronic cough and non-cardiac chest pain. Currently, the exact role reflux of gastric contents play in the pathogenesis of extraoesophageal symptoms remain controversial. Twenty-four hours pH monitoring is often considered the 'gold standard' in the diagnosis of gastro-oesophageal reflux disease and is increasingly utilized in patients with extraoesophageal symptoms. The use of this test is aimed at improving the association between patients' extraoesophageal symptoms and oesophageal or hypopharyngeal acid reflux events. However, the clinical utility of pH monitoring in this patient population remains controversial. Important clinical questions in this area include: does the presence of abnormal oesophageal acid reflux suggest a causal association between patients' extraoesophageal symptoms and gastro-oesophageal reflux disease? Conversely, does the absence of abnormal acid exposure in the oesophagus suggest lack of such an association? Should the test be performed on or off therapy and does it matter? In this study, the role of pH monitoring in laryngitis, asthma, chronic cough and non-cardiac chest pain is examined and answers to the above questions are addressed based on current data.

Timed barium oesophagram: better predictor of long term success after pneumatic dilation in achalasia than symptom assessment

BACKGROUND

Symptom relief post pneumatic dilation is traditionally used to assess treatment success in achalasia patients. Recently, we showed that symptom relief and objective oesophageal emptying are concordant in about 70% of patients, while up to 30% of achalasia patients report near complete symptom relief despite poor oesophageal emptying of barium.

AIMS

We now report the results of long term clinical follow up in these two groups of achalasia patients, assessing differences in symptomatic remission rates.

METHODS

Achalasia patients undergoing pneumatic dilation since 1995 were evaluated both symptomatically and objectively at regular intervals. Pre and post dilation symptoms were recorded. Barium column height was measured five minutes after ingesting a fixed volume of barium per patient to assess oesophageal emptying. Patients who initially reported near complete symptom relief were divided into two groups based on objective findings on barium study: (1) complete oesophageal emptying (concordant group), and (2) poor oesophageal emptying (discordant group). Patients were followed prospectively for symptom recurrence.

RESULTS

Thirty four patients with complete symptom relief post pneumatic dilation were identified. In 22/34 (65%) patients, the degree of symptom and barium height improvements was similar (concordant group). In 10/34 (30%) patients, there was < 50% improvement in barium height (discordant group). Significantly (p<0.001) more discordant (9/10; 90%) than concordant (2/22; 9%) patients failed therapy at the one year follow up. Seventeen of 22 (77%) concordant patients were still in remission while all discordant patients had failed therapy by six years of follow up. Length of time in symptom remission (mean (SEM)) post pneumatic dilation was significantly (p=0.001) less for the discordant group (18.0 (3.6) months) compared with the concordant group (59.0 (4.8) months).

CONCLUSIONS

(1) Poor oesophageal emptying is present in nearly 30% of achalasia patients reporting complete symptom relief post pneumatic dilation. (2) The majority (90%) of these patients will fail within one year of treatment. (3) Timed barium oesophagram is an important tool in the objective evaluation of achalasia patients post pneumatic dilation.

Duodenogastroesophageal reflux and methods to monitor nonacidic reflux

The role of duodenogastroesophageal reflux (DGER), once erroneously termed "bile reflux," in causing esophageal mucosal damage has been an area of interest in both animal and human studies. However, because of the lack of appropriate techniques to accurately measure DGER, extrapolation of findings from animal studies to humans has been difficult to make. The recent advent of the Bilitec system (Metronics Instruments, Minneapolis, MN), an ambulatory bilirubin monitoring device, is increasing our knowledge of the specific role of DGER in esophageal diseases. Studies suggest that DGER without acid reflux may result in symptoms, but unless acid reflux is present simultaneously, it does not cause esophagitis. Therefore, therapies should aim at reducing both DGER and acid reflux. Studies show that this may be accomplished by antireflux surgery or the use of proton pump inhibitors, which by reducing gastric volume, decrease the damaging potential of both acid and DGER.

Ambulatory gastric pH monitoring: proper probe placement and normal values

BACKGROUND

Gastric acid production may persist while patients are treated with proton pump inhibitors. Twenty-four-hour intragastric pH monitoring is being used to identify gastric acid in the stomach while on medical therapy.

AIM

To identify the optimal region of the stomach to demonstrate the presence of gastric acid.

METHOD

Probe locations confirmed with fluoroscopy after placement and prior to removal. In experiment 1, five volunteers underwent simultaneous, 24-h gastro-oesophageal pH monitoring with the pH sensors located in the gastric antrum, body, fundus and distal oesophagus. In experiment 2, five volunteers underwent simultaneous 24-h pH monitoring with sensors located side by side in the gastric fundus assessing the reproducibility of gastric pH in this region. In experiment 3, 35 volunteers underwent 24-h pH monitoring with pH sensors located in the distal oesophagus and gastric fundus. The mean percentage time for which pH < 4 was calculated for total, upright, and supine time periods.

RESULTS

pH profiles for the gastric fundus and body are similar-the mean percentage total time for which pH < 4 was 92.2% and 90.1%, respectively (P=N.S.). These values are significantly different from the antrum; pH < 4=54.6% (P < 0.01). pH values from the gastric fundus are highly reproducible (linear regression P= 0.004, r(2)=0.96). The normal values (mean +/- 95th percentile) for percentage time gastric pH < 4 in the fundus were: total 95.6 +/- 1.5%, upright 94.8 +/- 1.8%, and supine 96.5 +/- 2.3%.

CONCLUSION

The fundus is the optimal location to evaluate the presence of gastric acid; pH values are highly reproducible in this area. Normal values for percentage time gastric pH < 4 for a healthy population are now defined.

New techniques in measuring nonacidic esophageal reflux

New techniques in esophageal monitoring are allowing for better differentiation in the role of different gastric refluxates in esophageal mucosal damage and patient symptoms. The Bilitec 2001 (Synectics, Stockholm, Sweden) is a portable spectrophotometer that measures bilirubin as a surrogate marker for bile reflux and multichannel intraluminal impedance (MII) (Sandhill Scientific Inc, Highlands Ranch, CO) is a new technique allowing measurement of esophageal volume refluxate. Both techniques assess the role of nonacidic esophageal reflux. Despite their novel approach in assessing nonacid reflux, both methods have limitations. Future studies in this area, however, will prove beneficial in identifying their role in diagnosis and management of patients with suspected nonacid reflux disease.

Quantitative methods to determine efficacy of treatment in achalasia

Determining success after achalasia therapy is an important aspect of treating this disease. Esophageal manometry, scintigraphy, and barium esophagram are the most commonly employed techniques. Recent data suggest that barium esophagram may be most practical and informative compared to manometry and scintigraphy in predicting treatment success in achalasia patients after therapy.

Duodenogastro-oesophageal reflux

The role of duodenogastro-oesophageal reflux (DGOR), once erroneously termed 'bile reflux', in causing oesophageal mucosal damage has been an area of interest in both animal and human studies. However, due to the lack of appropriate techniques for accurately measuring DGOR, extrapolation of findings from animal studies to humans was difficult to make. The recent advent of the Bilitec system, an ambulatory bilirubin monitoring device, is increasing our knowledge of the specific role of DGOR in oesophageal diseases. Studies suggest that the DGOR without acid reflux may result in symptoms but unless acid reflux is present simultaneously, it does not cause oesophagitis. Therefore, our therapies should aim at reducing both DGOR and acid reflux. Studies show that this may be accomplished by anti-reflux surgery or the use of proton pump inhibitors, which, by reducing gastric volume, decrease the damaging potential of both acid and DGOR.

A cost-minimization analysis of alternative treatment strategies for achalasia

OBJECTIVE

The aim of this study is to compare the costs per cure of alternative strategies for the treatment of achalasia.

METHODS

A cost-minimization model compared three strategies for otherwise healthy adults of any age with achalasia: 1) laparoscopic Heller myotomy with fundoplication (LHM); 2) pneumatic dilation (PD), with LHM reserved for treatment failures; 3) botulinum toxin (Botox) injection of the lower esophageal sphincter, with PD reserved for treatment failures. Probabilities of short- and long-term efficacy, treatment failure, symptomatic recurrence rates, and complications were derived from the published literature. Only direct costs were considered during the 5-yr time horizon.

RESULTS

Respective reference case costs per cure of PD, Botox, and LHM strategies were $3,111, $3,723, and $10,792. Despite short- and long-term efficacy of 96% and 94%, respectively, the LHM strategy was most costly. Initial PD remained less costly than initial Botox, provided that rates of PD efficacy and perforation were > or = 70% and < 9.5%, respectively, and cost of a Botox session was > or = $450. The results were not sensitive to the probabilities of short- and long-term response to Botox, recurrence after PD, LHM efficacy, and post-LHM gastroesophageal reflux disease, nor to the costs of LHM and PD.

CONCLUSIONS

For otherwise healthy patients with achalasia, initial PD is the least costly strategy provided that the PD perforation rate remains < 10%. Initial Botox is less costly only when nonendoscopic-related costs decrease by 25%. Initial LHM is the most costly strategy under all clinically plausible scenarios. Subsequent analyses should include a longer time horizon and an assessment of patient ference for each strategy.

CagA-positive strains of Helicobacter pylori may protect against Barrett's esophagus

OBJECTIVE

Helicobacter pylori (H. pylori) colonization is associated with chronic gastritis, peptic ulcer disease, and adenocarcinoma of the distal stomach. However, the role of H. pylori strain variation in complicated gastroesophageal reflux disease, especially Barrett's esophagus, is unknown. Therefore, the aim of this study was to evaluate the prevalence of colonization by cagA+ and cagA- H. pylori strains in the spectrum of gastroesophageal reflux disease, including Barrett's esophagus.

METHODS

A total of 251 patients undergoing endoscopy were categorized into four groups: controls, patients with gastroesophageal reflux disease alone, and patients with short- and long-segment Barrett's esophagus. All patients underwent upper endoscopies with biopsies and serum collections. H. pylori and degree of mucosal inflammation in gastric biopsies were assessed and serological assessment made for H. pylori and cagA status.

RESULTS

The overall prevalence of H. pylori colonization in the study population was 35% (95% confidence interval = 29.5-41.4%) which did not differ significantly among the groups. However, colonization by cagA+ H. pylori strains was significantly more prevalent among controls (11/25; 44%) and patients with gastroesophageal reflux disease (13/36; 36%) than in patients with short-segment (2/10; 20%) or long-segment Barrett's esophagus (0/18; 0%). Patients with Barrett's esophagus were less likely to be colonized by cagA+ H. pylori strains than reflux patients without Barrett's esophagus (odds ratio = 0.27, 95% confidence interval = 0.11-0.67, p = 0.004).

CONCLUSIONS

Colonization by cagA+ H. pylori strains may be protective against the formation of short- and long-segment Barrett's esophagus and its malignant complications.

Cytokeratin immunoreactivity patterns in the diagnosis of short-segment Barrett's esophagus

BACKGROUND & AIMS

The origin of intestinal metaplasia in short segments of columnar mucosa at the esophagogastric junction has clinical importance but can be difficult to determine at endoscopy. Cytokeratin (CK) 7 and 20 patterns are specific for long-segment Barrett's esophagus; however, their utility in short-segment Barrett's esophagus has not been assessed.

METHODS

Endoscopic biopsy specimens from patients with long-segment Barrett's esophagus (n = 49), suspected short-segment Barrett's esophagus (n = 43), and gastric intestinal metaplasia (n = 26) were immunostained for CK7 and CK20. Comprehensive clinical data were obtained, including age, gender, and hiatal hernia and Helicobacter pylori status.

RESULTS

A Barrett's CK7/20 pattern was present in 48 (98%) of 49 patients with long-segment Barrett's esophagus, 35 (82%) of 43 with suspected short-segment Barrett's esophagus, and 0 (0%) of 26 patients with gastric intestinal metaplasia. Patients with suspected short-segment Barrett's esophagus with a Barrett's CK7/20 pattern were clinically similar to those with long-segment Barrett's esophagus. In contrast, patients with suspected short-segment Barrett's esophagus with no Barrett's CK7/20 pattern were clinically similar to those with gastric intestinal metaplasia.

CONCLUSIONS

A Barrett's CK7/20 pattern identifies a subset of patients with suspected short-segment Barrett's esophagus who have a patient profile similar to that seen in long-segment Barrett's esophagus. A Barrett's CK7/20 pattern is an objective marker of Barrett's mucosa that in conjunction with appropriate clinical and endoscopic data can be used by clinicians to better define patients with short-segment Barrett's esophagus.

Role of Helicobacter pylori cagA(+) strains and specific host immune responses on the development of premalignant and malignant lesions in the gastric cardia

The incidence rates of gastric cardia and esophageal adenocarcinomas are increasing, but data suggest that carriage of cagA(+) Helicobacter pylori strains may protect against development of Barrett's esophagus and esophageal adenocarcinoma. Our aims were to examine the relationship between pre-malignant and malignant lesions in the gastric cardia and serum antibodies to H. pylori antigens in patients with and without complications of Barrett's esophagus. The prevalence of carditis was 40% in controls compared with 13% in patients with complicated or uncomplicated Barrett's esophagus and cardia adenocarcinoma (p < 0.001). Cardia intestinal metaplasia (IM) and atrophy were present and concordant in 28% of controls but less frequent in patients with Barrett's alone or with dysplasia/adenocarcinoma (0% for each, p < 0.001). Carriage of cagA(+) strains was present in 34% of patients with carditis and significantly associated with increased frequency and severity of cardia inflammation, IM, and atrophy but not with adenocarcinoma. IgA and HspA seropositivity were significantly increased in H. pylori-colonized patients with carditis compared to persons with normal cardia histology (p </= 0.005) but not in persons with esophageal disease or cardia adenocarcinoma. We conclude that carriage of cagA(+) H. pylori strains and induction of particular serological responses are significantly associated with marked histological findings in the gastric cardia but not with adenocarcinoma of either the gastric cardia or esophagus.

Role of Helicobacter pylori cagA(+) strains and specific host immune responses on the development of premalignant and malignant lesions in the gastric cardia

The incidence rates of gastric cardia and esophageal adenocarcinomas are increasing, but data suggest that carriage of cagA(+) Helicobacter pylori strains may protect against development of Barrett's esophagus and esophageal adenocarcinoma. Our aims were to examine the relationship between pre-malignant and malignant lesions in the gastric cardia and serum antibodies to H. pylori antigens in patients with and without complications of Barrett's esophagus. The prevalence of carditis was 40% in controls compared with 13% in patients with complicated or uncomplicated Barrett's esophagus and cardia adenocarcinoma (p < 0.001). Cardia intestinal metaplasia (IM) and atrophy were present and concordant in 28% of controls but less frequent in patients with Barrett's alone or with dysplasia/adenocarcinoma (0% for each, p < 0.001). Carriage of cagA(+) strains was present in 34% of patients with carditis and significantly associated with increased frequency and severity of cardia inflammation, IM, and atrophy but not with adenocarcinoma. IgA and HspA seropositivity were significantly increased in H. pylori-colonized patients with carditis compared to persons with normal cardia histology (p </= 0.005) but not in persons with esophageal disease or cardia adenocarcinoma. We conclude that carriage of cagA(+) H. pylori strains and induction of particular serological responses are significantly associated with marked histological findings in the gastric cardia but not with adenocarcinoma of either the gastric cardia or esophagus.

Role of Helicobacter pylori cagA(+) strains and specific host immune responses on the development of premalignant and malignant lesions in the gastric cardia

The incidence rates of gastric cardia and esophageal adenocarcinomas are increasing, but data suggest that carriage of cagA(+) Helicobacter pylori strains may protect against development of Barrett's esophagus and esophageal adenocarcinoma. Our aims were to examine the relationship between pre-malignant and malignant lesions in the gastric cardia and serum antibodies to H. pylori antigens in patients with and without complications of Barrett's esophagus. The prevalence of carditis was 40% in controls compared with 13% in patients with complicated or uncomplicated Barrett's esophagus and cardia adenocarcinoma (p < 0.001). Cardia intestinal metaplasia (IM) and atrophy were present and concordant in 28% of controls but less frequent in patients with Barrett's alone or with dysplasia/adenocarcinoma (0% for each, p < 0.001). Carriage of cagA(+) strains was present in 34% of patients with carditis and significantly associated with increased frequency and severity of cardia inflammation, IM, and atrophy but not with adenocarcinoma. IgA and HspA seropositivity were significantly increased in H. pylori-colonized patients with carditis compared to persons with normal cardia histology (p </= 0.005) but not in persons with esophageal disease or cardia adenocarcinoma. We conclude that carriage of cagA(+) H. pylori strains and induction of particular serological responses are significantly associated with marked histological findings in the gastric cardia but not with adenocarcinoma of either the gastric cardia or esophagus.

Assessment of esophageal emptying post-pneumatic dilation: use of the timed barium esophagram

OBJECTIVES

The reported success rate of pneumatic dilation in patients with achalasia varies from 50% to 93%. This wide variability may be due to using symptom relief post-dilation as the only assessment of success. There are no studies comparing subjective symptom improvements to objective improvement in esophageal emptying after pneumatic dilation.

METHODS

Patients with achalasia undergoing pneumatic dilation from 1995 to 1997 were evaluated. Pre- and post-dilation symptoms were recorded using a standardized scoring system. Barium column height was measured 1 min and 5 min after upright ingestion to assess esophageal emptying. Based on percentage of total symptom and barium height improvement post-dilation, patients were grouped according to one of nine outcomes; the association between subjective and objective parameters of improvement was tested.

RESULTS

A total of 37 patients underwent 53 pneumatic dilations. There was a significant association (p < 0.001) between improvement in patient symptoms and barium height. In 38 of 53 (72%) pneumatic dilations, the degree of symptom and barium height improvement was similar. Near complete symptom resolution was reported after 26 dilations. In eight of 26 (31%) patients however, there was < 50% improvement in barium height (group A). Compared with the 16 patients with 91-100% improvement in both symptoms and barium height (group B), forward stepwise regression identified age as the only difference between the two groups, with group A patients being significantly (p = 0.04) older.

CONCLUSIONS

Objective assessment of esophageal emptying pre- and post-dilation identifies an important subset of patients with poor esophageal emptying who report near complete symptom resolution. This group may benefit from any early repeat pneumatic dilation.

Achalasia: diagnosis and management

Achalasia is a primary esophageal motor disorder of unknown cause that produces complaints of dysphagia, regurgitation, and chest pain. The current treatments for achalasia involve the reduction of lower esophageal sphincter (LES) pressure, resulting in improved esophageal emptying. Calcium channel blockers and nitrates, once used as an initial treatment strategy for early achalasia, are now used only in patients who are not candidates for pneumatic dilation or surgery, and in patients who do not respond to botulinum toxin injections. Because of the more rigid balloons, the current pneumatic dilators are more effective than the older, more compliant balloons. The graded approach to pneumatic dilation, using the Rigiflex (Boston Scientific Corp, Boston, MA) balloons (3.0, 3.5, and 4.0 cm) is now the most commonly used nonsurgical means of treating patients with achalasia, resulting in symptom improvement in up to 90% of patients. Surgical myotomy, once plagued by high morbidity and long hospital stay, can now be performed laparoscopically, with similar efficacy to the open surgical approach (94% versus 84%, respectively), reduced morbidity, and reduced hospitalization time. Because of the advances in both balloon dilation and laparoscopic myotomy, most patients with achalasia can now choose between these two equally efficacious treatment options. Botulinum toxin injection of the LES should be reserved for patients who can not undergo balloon dilation and are not surgical candidates.

Cytokeratin subsets can reliably distinguish Barrett's esophagus from intestinal metaplasia of the stomach

The histological distinction between intestinal metaplasia involving the distal esophagus (Barrett's esophagus [BE]) and intestinal metaplasia of the stomach has important clinical implications and can be difficult even with the use of histochemical mucin stains. Cytokeratin (CK) 7 and 20 are cytoplasmic structural proteins that show restricted expression in normal and malignant epithelia of the gastrointestinal tract. The aim of this study was to determine the use of CK7 and 20 expression in the histological distinction of BE from gastric intestinal metaplasia. CK7 and 20 immunostaining was performed on randomly selected surgical resection (n = 31) and biopsy specimens (n = 34) from patients with long-segment BE and gastric resection specimens (n = 11) and gastric cardia biopsy specimens (n = 13) in patients with histological evidence of intestinal metaplasia. A unique pattern of immunoreactivity designated the Barrett's CK7/20 pattern showed superficial CK20 staining and strong CK7 staining of both superficial and deep glands in 29 of 31 (94%) esophageal resection specimens and 34 of 34 (100%) esophageal biopsy specimens form patients with long-segment BE. A Barrett's CK7/20 pattern was not observed in gastric cardia biopsy specimens (n = 13) or gastric resection specimens (n = 11) in patients with histological evidence of intestinal metaplasia. The sensitivity, specificity, and positive predictive value of a Barrett's CK7/20 pattern for a diagnosis of long-segment BE was 97%, 100%, and 100%, respectively. CK7 and 20 reactivity patterns can reliably identify the location of intestinal metaplasia in the esophagus and stomach using histological material from both routine endoscopic biopsy and surgical resection specimens.

Botulinum toxin versus pneumatic dilatation in the treatment of achalasia: a randomised trial

BACKGROUND

Intrasphincteric injection of botulinum toxin is a new treatment option for achalasia.

AIMS

To compare the immediate and long term efficacy of botulinum toxin with that of pneumatic dilatation.

METHODS

Symptomatic patients with achalasia were randomised to botulinum toxin (22 patients, median age 57 years) or pneumatic dilatation (20 patients, median age 56 years). Symptom scores were assessed initially, and at one, three, six, nine, and 12 months after treatment. Objective assessment included oesophageal manometry initially and at one month, and barium oesophagram initially and at one, six, and 12 months post-treatment.

RESULTS

Pneumatic dilatation resulted in a significantly (p=0.02) higher cumulative remission rate. At 12 months, 14/20 (70%) pneumatic dilatation and 7/22 (32%) botulinum toxin treated patients were in symptomatic remission (p=0.017). Failure rates were similar initially, but failure over time was significantly (p=0.01) higher after botulinum toxin (50%) than pneumatic dilatation (7%). Pneumatic dilatation resulted in significant (p<0.001) reduction in symptom scores, and lower oesophageal sphincter pressure, oesophageal barium column height, and oesophageal diameter. Botulinum toxin produced significant reduction in symptom scores (p<0.001), but no reduction in objective parameters.

CONCLUSIONS

At one year pneumatic dilatation is more effective than botulinum toxin. Symptom improvement parallels objective oesophageal measurements after pneumatic dilatation but not after botulinum toxin treatment for achalasia.

Importance of duodeno-gastro-esophageal reflux in the medical outpatient practice

BACKGROUND/AIMS

The role of acid and duodeno-gastro-esophageal reflux (DGER), also termed bile reflux, in esophageal mucosal injury is controversial. Several recent developments, especially availability of the recent bilirubin monitoring device (Bilitec), have resulted in clarifications in this area. In order to better understand the role of acid and DGER in esophageal mucosal injury, we summarized the recent publications in this area.

METHODOLOGY

Review of published medical literature (MEDLINE) on the clinical consequence of esophageal exposure to gastric acid or DGER.

RESULTS

Recent data suggest that esophageal pH monitoring and pH > 7 is a poor marker for reflux of duodenal contents into the esophagus. DGER in non-acidic environments (i.e., partial gastrectomy patients) may cause symptoms but does not cause esophageal mucosal injury. Acid and duodenal contents usually reflux into the esophagus simultaneously, and may be contributing to the development of Barrett's metaplasia and possibly adenocarcinoma. Proton pump inhibitors decrease acid and DGER by reducing intragastric volume available for reflux and raising intragastric pH. The promotility agent cisapride decreases DGER by increasing LES pressure and improving gastric emptying.

CONCLUSIONS

1) The term "alkaline reflux" is a misnormer and should no longer be used in referring to reflux of duodenal contents. 2) Bilitec is the method of choice in detecting DGER and should always be used simultaneously with esophageal pH-monitoring for acid reflux. 3) DGER alone is not injurious to esophageal mucosa, but can result in significant esophageal mucosal injury when combined with acid reflux. 4) Therefore, controlling esophageal exposure to acid reflux by using proton pump inhibitors also eliminates the potentially damaging effect of DGER.

Helicobacter pylori and gastroesophageal reflux disease: the bug may not be all bad

Peptic ulcer disease and gastric cancer of the antrum and body have been declining in the 20th century. In contrast, a new group of diseases are increasingly rapidly in Western countries: gastroesophageal reflux disease, Barrett's esophagus, and adenocarcinoma of the distal esophagus. Recent studies suggest this phenomenon may be related to the simultaneous fall in the prevalence of Helicobacter pylori (H. pylori) colonization, especially by the virulent cagA + strains. H. pylori infection with the cagA+ strain is potentially protective against the spectrum of gastroesophageal reflux disease because it lowers intragastric acidity as the result of a pangastritis, frequently with multifocal gastric atrophy and possibly increased intragastric ammonia production. Assuming that some types of H. pylori strains are protective, our entire approach to the worldwide elimination of this organism, sometimes indiscriminately, will need critical reevaluation.

Current therapies for achalasia: comparison and efficacy

Achalasia is a primary esophageal motor disorder of unknown etiology producing complaints of dysphagia, regurgitation, and chest pain. The current treatments for achalasia involve the reduction of lower esophageal sphincter (LES) pressure resulting in improved esophageal emptying. Calcium channel blockers and nitrates, once used as initial treatment strategy for early achalasia, are now only used in patients who are not candidates for pneumatic dilation or surgery and those not responding to botulinum toxin injections. By virtue of the more rigid balloons, the current pneumatic dilators are more effective and have better efficacy than the older more compliant balloons. The graded approach to pneumatic dilation using the Rigiflex balloons (3.0, 3.5, and 4.0 cm) are now the most commonly used nonsurgical means of treating patients with achalasia, resulting in symptom improvement in up to 90% of patients. Surgical myotomy, once with high morbidity and long hospital stay, can now be performed laparoscopically with similar efficacy to the open surgical approach (94% vs. 84%, respectively), reduced morbidity, and hospitalization time. Given the advances in both balloon dilation and laparoscopic myotomy, most patients with achalasia can now choose between these two equally efficacious treatment options. Botulinum toxin injection of the LES should be reserved for patients who cannot undergo balloon dilation and are not surgical candidates.

Contribution of acid and duodenogastro-oesophageal reflux to oesophageal mucosal injury and symptoms in partial gastrectomy patients [see comment]

BACKGROUND

The role of acid and pepsin in causing symptoms and oesophagitis is well established; however, the significance of duodenogastro-oesophageal reflux (DGOR) in this disorder is unclear.

AIMS

To understand the role of acid and DGOR in causing upper gastrointestinal (GI) symptoms and oesophageal mucosal injury in partial gastrectomy (PG) patients.

METHODS

Thirty two PG patients with upper GI symptoms were studied. Twenty four hour ambulatory acid and bilirubin measurements were obtained with Bilitec 2000 using glass electrode and fibreoptic sensor. Upper GI symptoms and oesophagitis were correlated with either acid or DGOR.

RESULTS

The PG patients were a heterogeneous group: 28% (9/32) had mixed reflux (acid+/DGOR+); 50% (16/32) had only DGOR (acid-/DGOR+); and 22% (7/32) had neither (acid-/DGOR-). Upper GI symptoms were associated with both mixed reflux (69%) and DGOR (24%). Six patients (67%) in the acid+/DGOR+ group had oesophagitis; no acid-/DGOR+ or acid-/DGOR- patients had oesophagitis. Mixed reflux showed a significant (p < 0.0001) association with oesophagitis, while DGOR did not (p = 0.3).

CONCLUSIONS

(1) The majority of upper GI symptoms and all cases of oesophagitis in the PG patients occurred in patients who had mixed refluxate (acid and DGOR); (2) DGOR without simultaneous acid reflux may cause symptoms, but was not associated with oesophagitis in this patient group.

Bile reflux in columnar-lined esophagus

Barrett's esophagus represents a metaplastic process in which the normal squamous epithelium of the lower esophagus is replaced by metaplastic columnar epithelium. Although the role of acid and pepsin in the development of Barrett's esophagus is well accepted, the importance of duodenogastroesophageal reflux in this disorder is not clear.

Reproducibility of proximal probe pH parameters in 24-hour ambulatory esophageal pH monitoring

OBJECTIVES

To assess the reproducibility and reliability of the proximal pH probe in detecting acid reflux into the proximal esophagus.

METHODS

Using dual probe ambulatory esophageal pH monitoring, we studied 32 subjects (11 healthy control subjects, 10 patients with distal esophageal acid reflux, and 11 patients with both distal and proximal esophageal acid exposure) on two separate days within a 20-day period. The distal pH probe was placed 5 cm above the manometrically determined lower esophageal sphincter, and the proximal probe was positioned immediately distal to the upper esophageal sphincter. Patients were categorized on the basis of the esophageal pH data obtained during the first study. Reflux parameters assessed were the percentages of time in which pH was <4 in the total, upright, and supine positions. To be considered reproducible, all three of the above parameters had to remain in the same category as the first day's results.

RESULTS

Intrasubject reproducibility of the proximal probe was 91-100% in healthy subjects, 70-90% in patients with distal esophageal acid reflux, and 45-73% in patients with proximal esophageal acid reflux. The proximal probe reproducibility for the overall diagnosis of gastroesophageal reflux disease was 91% in healthy subjects, 70% in patients with distal esophageal acid reflux, and only 55% in those with proximal esophageal acid reflux. Statistical analysis demonstrated only a fair index of concordance (kappa = 0.40) for the proximal probe.

CONCLUSIONS

The proximal pH probe has excellent specificity (91%) but poorer sensitivity and reproducibility (55%) for identifying abnormal amounts of proximal esophageal acid reflux. Therefore, a negative test result does not exclude proximal reflux with microaspiration as a cause of atypical reflux symptoms.

Twenty-four-hour ambulatory esophageal pH monitoring in the diagnosis of acid reflux-related chronic cough

To define the role of ambulatory pH monitoring in evaluating chronic cough, we studied esophageal pH values of patients referred to a gastroenterology laboratory. Chronic cough was evaluated in 31 patients, who were grouped based on response to treatments; 11 patients (35.5%) had gastroesophageal reflux (GER)-related cough, 11 (35.5%) had pulmonary/otorhinolaryngologic-related cough (1 bronchitis, 6 asthma, 2 postnasal drip, 1 pneumonia), and 9 patients (29%) had cough of unknown etiology. Esophageal pH values of groups were compared. Excessive acid reflux distally (upright and supine) and proximally (upright) and cough symptom frequency related to acid reflux were significantly higher in patients with GER. Esophageal pH monitoring had good sensitivity (91%), specificity (82%), and positive (83%) and negative (90%) predictive values in identifying GER-related cough. In summary, ambulatory pH monitoring is an excellent test for identifying patients with GER-related cough.

Role of acid and duodenogastroesophageal reflux in gastroesophageal reflux disease

BACKGROUND & AIMS

Acid and pepsin are known to cause esophagitis. However, the role of duodenogastroesophageal reflux (DGER) in producing esophageal mucosal injury across the spectrum of gastroesophageal reflux disease (GERD) is controversial.

METHODS

Twenty controls (13 men; mean age, 41 years), 30 patients with GERD (15 men; mean age, 41 years), and 20 patients with Barrett's esophagus (17 men; mean age, 58 years) were studied. Twenty-four-hour ambulatory acid and bilirubin measurements were obtained with Bilitec 2000 using a glass pH electrode and fiberoptic sensor.

RESULTS

Percentage times pH was < 4, bilirubin level was > or = 0.14, and fasting gastric bile acid concentrations showed a graded increase across the GERD spectrum. Esophageal exposure to both acid and DGER was the most prevalent reflux pattern (100% in patients with complicated and 89% in patients with uncomplicated Barrett's esophagus, 79% in patients with esophagitis, and 50% in patients without esophagitis). The majority (70%-91%) of DGER episodes occurred in an acidic environment (pH < 4). Linear regression analysis found a significant correlation (r = 0.73; P < 0.01) between percentage time pH was < 4 and percentage time bilirubin absorbance level was > or = 0.14.

CONCLUSIONS

Both acid and DGER show a graded increase in severity across the GERD spectrum. Acid and DGER occur simultaneously in the majority of the reflux episodes.

Conformationally defined 6-s-trans-retinoic acid analogs. 3. Structure-activity relationships for nuclear receptor binding, transcriptional activity, and cancer chemopreventive activity

We recently demonstrated that conformationally defined 6-s-trans-retinoic acid (RA) analogs were effective in the prevention of skin papillomas (Vaezi et al. J. Med. Chem. 1994, 37, 4499-4507) and selective agonists for nuclear receptor binding and activation (Alam et al. J. Med. Chem. 1995, 38, 2302-2310). In order to probe important structure-activity relationships, we evaluated a homologous series of four 6-s-trans-retinoids that are 8-(2'-cyclohexen-1'-ylidene)-3,7-dimethyl-2,4,6-octatrienoic acids with different substituents at 2' (R2) and 3' (R1) positions on the cyclohexene ring. UAB1 (R1 = R2 = H), UAB4 (R1 = R2 = Me), UAB7 (R1 = Me, R2 = iPr), and UAB8 (R1 = Et, R2 = iPr) contain alkyl R groups that mimic, to different extents, portions of the trimethylcyclohexenyl ring of RA. Both 9Z- and all-E-isomers of these retinoids were evaluated in binding assays for cellular retinoic acid-binding proteins (CRABP-I and CRABP-II), a nuclear retinoic acid receptor (RAR alpha), and a nuclear retinoid X receptor (RXR alpha). The all-E-isomers of UAB retinoids bound tightly to CRABPs and RAR alpha, the binding affinity of the all-E-isomer increased systematically from UAB1 to UAB8, and binding for the latter was comparable to that of all-E-RA. In contrast to RA, the (9Z)-UAB retinoids were at least 200-fold less active than the all-E-isomers in binding to RAR alpha. The (9Z)-UAB isomers exhibited increasingly stronger binding to RXR alpha, and (9Z)-UAB8 was nearly as effective as (9Z)-RA in binding affinity. The retinoids were also evaluated in gene expression assays mediated by RAR alpha and RXR alpha homodimers or RAR alpha/RXR alpha heterodimers. Consistent with the binding affinities, the (all-E)-UAB retinoids activated gene transciption mediated by RAR alpha homodimers or RAR alpha/RXR alpha heterodimers, while the (9Z)-UAB isomers activated only the RXR alpha homodimer-mediated transcription. The all-E- and 9Z-isomers of the UAB retinoids were further evaluated for their capacity to prevent the induction of mouse skin papillomas. When compared to RA, only the (all-E)-UAB retinoids containing bulky R1 and R2 groups were effective in this chemoprevention assay. (9Z)-RA displayed equal capacity as RA to prevent papillomas, while the 9Z-isomers of the UAB retinoids were much less effective. Taken together, these studies demonstrate that the cyclohexenyl ring substituents of 6-s-trans-UAB retinoids are important for their biological activities and that the chemopreventive effect of the all-E-isomers of these retinoids correlates well with their capacity to bind to RARs and activate RAR/RXR-mediated transcription.

Placebo-controlled trial of cisapride in postgastrectomy patients with duodenogastroesophageal reflux

Medical treatment of duodenogastroesophageal reflux in postgastrectomy patients has been disappointing. Using ambulatory esophageal bilirubin monitoring, we evaluated the efficacy of cisapride in this disorder. Ten chronically symptomatic partial gastrectomy patients (5 Billroth I, 5 Billroth II; 8 men; average age 57) with duodenogastroesophageal reflux were randomized to four weeks of either placebo or cisapride (20 mg four times a day) in a double-blind crossover study. Significantly improved patients continued to take cisapride for an additional four months. Duodenogastroesophageal reflux was assessed at baseline and after four weeks on each therapy. Daily diary recorded symptoms and mean monthly scores were determined. Global symptom improvements were assessed at the end of each treatment period. Compared to placebo, cisapride significantly (P < 0.05) decreased duodenogastroesophageal reflux. Overall symptom improvements were assessed at the end of each treatment period. Compared to placebo, cisapride significantly (P < 0.05) decreased duodenogastroesophageal reflux. Overall symptoms improved in 70% of patients on cisapride compared to 10% on placebo (P < 0.01). Mean monthly scores significantly (P < 0.05) improved for abdominal pain, regurgitation, and belching. These symptoms remained improved after four months of chronic therapy. We conclude that cisapride significantly reduces duodenogastroesophageal reflux and results in short- and long-term symptom improvements in postgastrectomy patients and that cisapride offers the first successful medical therapy for duodenogastroesophageal reflux in postgastrectomy patients.

An ambulatory bilirubin monitoring device for duodenogastroesophageal reflux

Reflux of duodenal contents into the stomach is a normal physiological event occurring most commonly at night' but also in the fasting and postprandial daytime periods.' Previously, the terms "bile reflux" and "alkaline reflux" have been used to describe this process. However, duodenal contents contain more than just "bile" and studies have shown that the term "alkaline reflux" is a misnomer since pH > 7 does not correlate with reflux of duodenal contents.' Therefore, duodenogastroesophageal reflux (DGER) may be a more appropriate term to describe the pathological regurgitation of duodenal contents through the pylorus into the stomach with subsequent reflux into the esophagus.