Diagnostic Tests for Gastroesophageal Reflux Disease

A novel scoring system for evaluating laryngopharyngeal reflux

OBJECTIVE

Although laryngopharyngeal reflux (LPR) is a common condition in daily practice, no gold standard exists for its diagnosis. The objective of this study was to establish a simple and reliable scoring system for evaluating LPR consisting of both subjective and objective criteria.

METHODS

This retrospective study includes 124 patients presenting with symptoms of LPR. In all patients, reflux symptom index (RSI), reflux finding score (RFS), oropharyngeal pH monitoring (PHM) and transnasal oesophagoscopy (TNE) were performed and rated in a special scoring system.

RESULTS

A Horvath Score of 4-5 for severe LPR was found in 76 patients (61%), a score of 2-3 for non-severe LPR in 38 patients (31%) and a score of 0-1 for non-existing LPR in 10 patients (8%) by combining the 4 validated diagnostic methods.

CONCLUSION

The proposed scoring system qualifies as a simple and reliable tool for evaluating LPR in daily practice, directly impacting patient management.

PROLONGED GASTROESOPHAGEAL REFLUX MONITORING BY IMPEDANCE-PHMETRY: A REVIEW OF THE SUBJECT PONDERED WITH OUR EXPERIENCE WITH 1,200 CASES

BACKGROUND

Prolonged monitoring increased our knowledge on gastroesophageal reflux (GER), and the disease became known as gastroesophageal reflux disease (GERD). Prolonged reflux monitoring permits the diagnosis of GERD when endoscopic findings are not enough to characterize it.

OBJECTIVE

The objective of this paper is to review the current knowledge on impedance-pH monitoring, taking into account the published literature and the authors experience with 1,200 exams.

METHODS

The different types of prolonged reflux monitoring, namely: conventional pHmetry, catheter-free pHmetry and impedance-pHmetry will be briefly described. The new possibilities of evaluation with impedance-pHmetry are emphasized, namely: the study of symptomatic patients in use of proton pump inhibitors (PPIs); evaluation of patients with symptoms suggestive of GERD although with normal endoscopy and normal pHmetry, diagnostic elucidation of patients with atypical symptoms or supra-esophageal symptoms, mainly chronic cough, study of patients complaining of belch, differentiating gastric and supra-gastric belching, and the proper work-up before anti-reflux surgery.

RESULTS

When impedance was associated to pH monitoring, an impressive technological evolution became apparent, when compared to pH monitoring alone. The main advantages of impedance-pHmetry are: the ability to detect all types of reflux: acid, non-acid, liquid, gaseous. In addition, other important measurements can be made: the ability of the esophagus in transporting the bolus, the measurement of basal mucosal impedance and the evaluation of primary peristalsis post reflux.

CONCLUSION

Impedance-pHmetry is a promising method, with great advantages over conventional pHmetry. The choice between these two types of monitoring should be very judicious. The authors suggest the importance of careful evaluation of each reflux episode by the physician responsible for the examination, necessary for the correct interpretation of the tracings.

Correlation between esophageal pH-metry and esophagitis in gastroesophageal reflux disease in children

Gastroesophageal reflux (GER) is the intermittent or permanent passage of stomach content into the esophagus and gastroesophageal reflux disease (GERD) is the reflux which triggers a whole set of symptoms or complications. The study compares the 24-hours esophageal pH-metry, used for diagnosis of the GERD, with the esophagitis degree observed at the upper digestive endoscopy.72 children were included, aged over 4 years old, admitted in a pediatric gastroenterology regional center in Northeast Romania, diagnosed with GERD by 24 hours pH-metry (with a positive Boix-Ochoa score), which also underwent the upper digestive endoscopy.Out of the 72 children diagnosed with GERD, 47 (65.28%) had grade A esophagitis and 25 (34.72%) grade B esophagitis. In GERD associated with grade B esophagitis the Boix-Ochoa score is statistically significant higher, compared with the GERD associated with grade A esophagitis (F = 9.76, P = .0036, 95% CI).Upper digestive endoscopy performed in patients with gastroesophageal reflux disease shows the constant presence of esophagitis at all patients. There were only grade A and B esophagitis due to the fact that they are young patients with a relative short history of the disease. The correlation tests show a perfect parallel between the pH-metry scores and the endoscopic lesion. The correlation is so accurate that the pH-metry scores can be sufficient to prove GERD and the grade of esophagitis, the upper digestive endoscopy being reserved only for the cases that does not respond to the medical treatment or have other complications.

The comparative analyses of different diagnostic approaches in detection of gastroesophageal reflux disease in children

Objectives

The aim of this study was to compare the different diagnostic approaches in detection of gastroesophageal reflux disease in children presented with symptoms suggesting gastroesophageal reflux disease.

Methods

The study design was cross sectional. The study retrospectively included all children who underwent combined multiple intraluminal impedance and pH (pH-MII) monitoring due to gastrointestinal and/or extraesophageal symptoms suggesting gastroesophageal reflux disease at University Children's Hospital in Belgrade, from July 2012 to July 2016.

Results

A total of 218 (117 boys/101 girls), mean age 6.7 years (range 0.06–18.0 years), met the inclusion criteria. Gastroesophageal reflux disease was found in 128 of 218 children (57.4%) by pH-MII and in 76 (34.1%) children by pH metry alone. Using pH-MII monitoring as gold standard, sensitivity of pH-metry was lowest in infants (22.9%), with tendency to increase in older age groups (reaching 76.4% in children ≥ 9 years). The sensitivity of pH-metry alone in children with extraesophageal symptoms was 38.1%, while the sensitivity of pH-metry in children with gastrointestinal symptoms was 63.8%. Reflux esophagitis was identified in 31 (26.1%) of 119 children who underwent endoscopy. Logistic regression analysis showed that best predictors of endoscopic reflux esophagitis are the longest acid episode (OR = 1.52, p<0.05) and DeMeester reflux composite score (OR = 3.31, p<0.05). The significant cutoff values included DeMeester reflux composite score ≥ 29 (AUC 0.786, CI 0.695–0.877, p<0.01) and duration of longest acid reflux ≥ 18 minutes (AUC 0.784, CI 0.692–0.875, p<0.01).

Conclusions

The results of our study suggested that compared with pH-metry alone, pH-MII had significantly higher detection rate of gastroesophageal reflux disease, especially in infants. Our findings also showed that pH-MII parameters correlated significantly with the endoscopically confirmed erosive esophagitis.

Prevalence and Risk Factors of Gastroesophageal Reflux Disease in Patients with Type 2 Diabetes Mellitus

BACKGROUND

Gastrointestinal symptoms are common in patients with type 2 diabetes mellitus (T2DM). The prevalence of gastroesophageal reflux disease (GERD) in Korea appears to be increasing. Some studies have shown that T2DM is a risk factor for symptomatic GERD. However, this possibility is still debated, and the pathogenesis of GERD in T2DM is not yet fully understood. The aim of this study was to analyze the prevalence and risk factors (including autonomic neuropathy) of GERD in patients with T2DM.

METHODS

This cross-sectional case-control study enrolled T2DM patients (n=258) and healthy controls (n=184). All participants underwent physical examinations and laboratory tests. We evaluated medical records and long-term diabetes complications, including peripheral and autonomic neuropathy in patients with T2DM. Esophagogastroduodenoscopy was performed in all patients. The Los Angeles (LA) classification was used to grade GERD. GERD was defined as LA grade A (or higher) or minimal change with GERD symptoms. GERD symptoms were examined using a frequency scale. Data were expressed as mean±standard error. Independent t-tests or chi-square tests were used to make comparisons between groups.

RESULTS

The prevalence of GERD (32.6% vs. 35.9%, P=0.266) and GERD symptoms (58.8% vs. 59.2%, P=0.503) was not significantly different between T2DM patients and controls. We found no significant differences between T2DM patients with GERD and T2DM patients without GERD with respect to diabetic complications, including autonomic neuropathy, peripheral neuropathy, duration of DM, and glucose control.

CONCLUSION

The prevalence of GERD in patients with T2DM showed no difference from that of controls. GERD was also not associated with peripheral and cardiovascular autonomic neuropathy, age, or duration of DM in patients with T2DM.

The role of endoscopy in the management of GERD

We recommend that uncomplicated GERD be diagnosed on the basis of typical symptoms without the use of diagnostic testing, including EGD. We recommend EGD for patients who have symptoms suggesting complicated GERD or alarm symptoms. We recommend that EGD not be routinely performed solely for the assessment of extraesophageal GERD symptoms. We recommend that endoscopic findings of reflux esophagitis be classified according to an accepted grading scale or described in detail. We suggest that repeat EGD be performed in patients with severe erosive esophagitis after at least an 8-week course of PPI therapy to exclude underlying BE or dysplasia. 44BB We recommend against obtaining tissue samples from endoscopically normal tissue to diagnose GERD or exclude BE in adults. We suggest that endoscopy be considered in patients with multiple risk factors for Barrett’s esophagus. We recommend that tissue samples be obtained to confirm endoscopically suspected Barrett’s esophagus. We suggest that endoscopic antireflux therapy be considered for selected patients with uncomplicated GERD after careful discussion with the patient regarding potential adverse effects, benefits, and other available therapeutic options.

Gastroesophageal Reflux Disease Diagnosis Using Hierarchical Heterogeneous Descriptor Fusion Support Vector Machine

A new computer-aided diagnosis method is proposed to diagnose the gastroesophageal reflux disease (GERD) from endoscopic images of the esophageal-gastric junction. To avoid the interferences of different endoscope devices and automatic camera white balance adjustment, heterogeneous descriptors computed from heterogeneous color models are used to represent endoscopic images. Instead of concatenating these descriptors to a super vector, a hierarchical heterogeneous descriptor fusion support vector machine (HHDF-SVM) framework is proposed to simultaneously apply heterogeneous descriptors for GERD diagnosis and overcome the curse of dimensionality problem. During validation, heterogeneous descriptors are extracted from test endoscopic images at first. The classification result is obtained by using HHDF-SVM with heterogeneous descriptors. As shown in the experiments, our method can automatically diagnose GERD without any manual selection of region of interest and achieve better accuracy compared to states-of-the-art methods.

[Updated guidelines 2012 for gastroesophageal reflux disease]

In 2010, a Korean guideline for the management of gastroesophageal reflux disease (GERD) was made by the Korean Society of Neurogastroenterology and Motility, in which the definition and diagnosis of GERD were not included. The aim of this guideline was to update the clinical approach to the diagnosis and management of GERD in adult patients. This guideline was developed by the adaptation process of the ADAPTE framework. Twelve guidelines were retrieved from initial queries through the Appraisal of Guidelines for Research & Evaluation II process. Twenty-seven statements were made as a draft and revised by modified Delphi method. Finally, 24 consensus statements for the definition (n=4), diagnosis (n=7) and management (n=13) of GERD were developed. Multidisciplinary experts participated in the development of the guideline, and the external review of the guideline was conducted at the finalization phase.

Managing gastroesophageal reflux disease in children: The role of endoscopy

Gastroesophageal reflux disease (GERD) is a growing problem in the pediatric population and recent advances in diagnostics and therapeutics have improved their management, particularly the use of esophago-gastroduodenoscopy (EGD). Most of the current knowledge is derived from studies in adults; however there are distinct features between infant onset and adult onset GERD. Children are not just little adults and attention must be given to the stages of growth and development and how these stages impact the disease management. Although there is a lack of a gold standard test to diagnose GERD in children, EGD with biopsy is essential to assess the type and severity of tissue damage. To date, the role of endoscopy in adults and children has been to assess the extent of esophagitis and detect metaplastic changes complicating GERD; however the current knowledge points another role for the EGD with biopsy that is to rule out other potential causes of esophagitis in patients with GERD symptoms such as eosinophilic esophagitis. This review highlights special considerations about the role of EGD in the management of children with GERD.

Accuracy of the water-siphon test associated to barium study in a high prevalence gastro-oesophageal reflux disease population: a novel statistical approach

RATIONALE, AIMS AND OBJECTIVES

Gastro-oesophageal reflux disease (GORD) is 'a condition which develops when the reflux of gastric content causes troublesome symptoms or complications'. Instrumental diagnostic tests generally used for GORD are 24-hour pH-metry and upper gastrointestinal (GI) endoscopy but barium study associated with provocative manoeuvres such as the water-siphon test (WST), has also been used for GORD. The aim of this paper was to estimate the accuracy of several tests in patients with GORD in a tertiary care setting, focusing on WST, which is rapid and non-invasive, simple to perform and well-tolerated by patients.

METHOD

A total of 172 consecutive patients, symptomatic for reflux referred to a tertiary medical centre, were considered and data regarding the WST, 24-hour pH-metry, upper GI endoscopy with histology were analysed using latent class analysis, a multivariable statistical method for estimating the accuracy of tests when a gold standard is not available.

RESULTS

The overall proportion of GORD in the sample was estimated at 0.664 [95% confidence interval (CI) = (0.589; 0.731)]. WST proved to be the most sensitive [Se = 0.886; 95% CI = (0.688; 1.000)] compared with pH-metry [Se = 0.620; 95% CI = (0.493; 0.745)] and endoscopy with histology [Se = 0.534; 95% CI = (0.273; 0.789)]. It was less specific [Sp = 0.537; 95% CI = (0.003; 1.000)] than pH-metry [Sp = 0.547; 95% CI = (0.281; 0.813)], and even less than endoscopy with histology [Sp = 0.862; 95% CI = (0.495; 1.00)]. Positive predictive values were estimated at 0.792 [95% CI = (0.721; 0.862)] for WST, 0.731 [95% CI = (0.643; 0.819)] for pH-metry and 0.886 [95% CI = (0.811; 0.961)] for endoscopy with histology. Negative predictive values were estimated at 0.707 [95% CI = (0.573; 0.841)] for WST, 0.422 [95% CI = (0.310; 0.534)] for pH-metry and 0.484 [95% CI = (0.387; 0.581)] for endoscopy with histology.

CONCLUSION

Water-siphon test might possibly be useful in patients with suspected GORD because it is highly sensitive and predictive. A positive outcome of the WST associated with a barium study can certainly justify upper GI endoscopy and support any pharmacological treatment of GORD.

Role of digital chromoendoscopy in detecting minimal change esophageal reflux disease

Endoscopy is a widely used diagnostic tool to detect reflux esophagitis. Although its specificity was reported to be excellent at 90%-95%, its sensitivity was only 50%. Therefore, it is quite difficult to detect these lesions under the standard white light endoscopy especially in patients with minimal change esophageal reflux disease (MERD). In recent years, endoscopic technologies have evolved tremendously; these include high resolution and magnification digital chromoendoscopy. These technologies are useful practically for detecting various subtle lesions along the gastrointestinal tract starting from esophagus to colon. Currently, these technologies can be classified in 2 systems; pre-processed system (NBI, Olympus) and post processed system (FICE and i-SCAN, Fujinon and Pentax respectively). Over a few years, there have been many emerging publications on the benefit of these systems on MERD detection. The overall sensitivities to diagnose MERD were reported as much better than controls. However, large, multi-center and randomized controlled studies comparing these new imaging modalities with the conventional white light chromoendoscopy are warranted to validate its accuracy. Standard, simple and precise endoscopic reading criteria for the identification of MERD are also required.

The use of frequency scale for the symptoms of GERD in assessment of gastro-oesophageal reflex symptoms in asthma

In adult asthmatics the incidence of gastro-oesophageal reflux disease (GERD) reportedly ranges from 34% to 89%. Oesophageal pH monitoring and endoscopy are not required in the patient with typical GERD symptoms before the initiation of a therapeutic trial. Diagnosis of GERD on the basis of history is the simplest and quickest method, placing no demand on patients. Recently, a new questionnaire (FSSG; Frequency Scale for the Symptoms of GERD) was produced to evaluate the severity and the therapeutic response of GERD. The FSSG (F-scale) was used to assess the GERD in subjects with persistent moderate to severe asthma treated with anti-inflammatory asthma medication. In the present study, 27.4% of the patients with asthma had symptoms suggestive of GERD. There is significant correlation between GERD symptom (F-scale score) and severity of cough and sputum. The observations suggested that reflux symptoms, not gastric dysmotility symptoms, significantly associated with severity of cough, not of sputum. It is the first such study to use a FSSG as incidence of GERD symptoms in asthmatics and examine the relationship between F-scale score and asthmatic symptoms.

The many manifestations of gastroesophageal reflux disease: presentation, evaluation, and treatment

Gastroesophageal reflux disease (GERD) is a common problem that is expensive to diagnose and treat. The disease is increasing in prevalence in the Western world, with important risk factors being obesity and the eradication of Helicobacter pylori. Heartburn and acid regurgitation are classic symptoms of GERD, but their sensitivity is poor. Ambulatory esophageal pH testing is the most sensitive test for GERD, whereas endoscopy is the most specific test. Medical treatment with proton pump inhibitors (PPIs) has revolutionized the treatment of GERD and its complications, but long-term side effects do exist. Laparoscopic anti-reflux surgery and PPIs have similar efficacy in the few available long-term trials. This article reviews the presentation, evaluation, and treatment of GERD.

Gastrooesophageal reflux disease

Gastrooesophageal reflux disease, GERD, is a common problem which is expensive to diagnose and treat. The disease is increasing in prevalence in the Western world with important risk factors being obesity and the eradication of Helicobacter pylori. Increasing research points to transient LES relaxation and spatial separation of the diaphragm and LES (hiatal hernia in chest) being the critical mechanisms of acid reflux. Heartburn and acid regurgitation are classic symptoms of GERD, but their sensitivity is poor. Ambulatory oesophageal pH testing is the most sensitive test for GERD, while endoscopy is the most specific test. Medical treatment with PPIs has revolutionized the treatment of GERD and its complications, but long-term side effects do exist. Laparoscopic antireflux surgery and PPIs have similar efficacy in the few available long-term trials. Currently, endoscopic treatments for GERD should not be a clinical alternative outside of research trials. New drug therapies should be directed at modulating transient LES relaxation.

Healing of severe reflux esophagitis with PPI does not improve esophageal dysmotility

Esophageal dysmotility is frequently associated with gastroesophageal reflux disease (GERD). The aim of this study was to investigate the relationship between the severity of reflux esophagitis and esophageal dysmotility and evaluate the effect of prolonged treatment with proton pump inhibitor (lansoprazole 30 mg/day) on esophageal motility in patients with severe reflux esophagitis associated with esophageal motility disorder. Twelve healthy subjects (HS) and 100 patients with reflux disease were involved in the study consisting of two parts: (i) comparison of esophageal motility in HS and patients with non-eroseive reflux disease (NERD), mild esophagitis and severe esophagitis; (ii) effect of 3-6 months lansoprazole therapy on esophageal motility in 23 patients with severe esophagitis, pathologic acid reflux and esophageal peristaltic dysfunction. Results included the following. (i) Esophageal dysmotility was noted in both patients with NERD and erosive GERD. (ii) Severe esophagitis was associated with severe esophageal dysmotility. (iii) Healing of severe esophagitis did not improve esophageal dysmotility. The resting lower esophageal sphincter pressure was 3.9 mmHg (range 1.7-20) before treatment and 4.8 mmHg (range 1.2-18.3) after esophagitis healing (P = 0.23, vs. before treatment), the amplitude of distal esophageal contraction was 28.8 mmHg (range 10.9-80.6) before treatment and 33.3 mmHg (range 10.0-72.5) after esophagitis healing (P = 0.59, vs. before treatment) and the frequency of failed peristalsis was 70% (range 0-100%) before treatment and 70% (range 0-100%) after esophagitis healing (P = 0.78, vs. before treatment). Both esophageal motility disorders and acid reflux play important roles in the mechanism of GERD, especially in severe esophagitis. Esophageal dysmotility is not secondary to acid reflux and esophagitis; it should be a primary motility disorder.

The frontiers of reflux disease

Gastroesophageal reflux disease has frequently been implicated in a wide variety of complications beyond the esophagus. These so-called "extraesophageal" disorders range from diseases of the respiratory tract, such as asthma and bronchitis, to more remote sites and conditions such as otitis and dental erosion. Many articles proposing a link between reflux disease and a multitude of extraesophageal complications have been published, but indisputable evidence that these conditions are caused by reflux disease is rare. Much of the support for a link between reflux disease and a number of extraesophageal complications is based on the observation that reflux disease frequently coexists with other disorders. A causal link is difficult to prove, however, and this review aims to critically evaluate the available evidence, looking, where possible, at longitudinal studies, expert diagnoses, and response to acid-suppressive therapy as a means of determining the true relationship between GERD and its putative extraesophageal complications.

Gastro-oesophageal reflux disease

Gastro-oesophageal reflux disease refers to reflux of gastric contents into the oesophagus leading to oesophagitis, reflux symptoms sufficient to impair quality of life, or long-term complications. Transient relaxation of the lower oesophageal sphincter is believed to be the primary mechanism of the disease although the underlying cause remains uncertain. Obesity and smoking are weakly associated with the disease and genetic factors might be important. A negative association with Helicobacter pylori exists, but eradication of H pylori does not seem to cause reflux disease. Diagnosis is imprecise as there is no gold standard. Reflux symptoms are helpful in diagnosis but they lack sensitivity. Ambulatory oesophageal pH monitoring also seems to be insensitive despite high specificity. Empirical acid suppression with a proton-pump inhibitor (PPI) has reasonable sensitivity but poor specificity. Some evidence suggests that once patients develop the disease, severity is determined early and patients seem to continue with that phenotype long term. Unfortunately, most patients do not respond to life-style advice and require further therapy. H2 receptor antagonists and PPIs are better than placebo in oesophagitis, with a number needed to treat of five and two, respectively. In non-erosive reflux disease, acid suppression is better than placebo but the response rate is lower. Most patients need long-term treatment because the disease usually relapses. The role of endoscopic therapy is uncertain. Anti-reflux surgery is probably as effective as PPI therapy although there is a low operative mortality and morbidity.

Surgical approach to gastroesophageal reflux disease: what the radiologist needs to know

Gastroesophageal reflux disease (GERD) is defined as gastroesophageal reflux resulting in symptoms or in injury to the esophageal epithelium. Although the medical management of GERD has improved, an increasing number of laparoscopic antireflux surgical procedures are being performed. Barium studies, endoscopy, manometry, and pH monitoring are all integral components of preoperative evaluation. Barium swallow examination must allow critical evaluation of esophageal peristalsis, the presence and extent of gastroesophageal reflux, and complications including esophagitis, stricture, and Barrett esophagus. It is crucial to identify and characterize hiatal hernia and longitudinal stricture, which can result in a shortened esophagus. In such cases, it becomes necessary for the surgeon to incorporate an esophageal lengthening procedure prior to fundoplication; otherwise, poor surgical outcome is likely. Normal postfundoplication radiographic findings as well as postoperative complications (eg, tight wrap, perforation, abscess, complete or partial dehiscence, recurrent stricture, recurrent hernia, intrathoracic migration of the wrap) must also be recognized and clearly understood by the radiologist. Given the chronic nature and prevalence of symptomatic GERD and the increasing number of patients undergoing surgical intervention, it is imperative that the radiologist understand the pre- and postsurgical evaluation of affected patients.

Endoscopic measurement of cardia circumference as an indicator of GERD

BACKGROUND

It is theorized that repeated gastric distention leads to dilatation of the cardia and the development of GERD. We hypothesize that cardia circumference correlates with the presence and the severity of GERD, and we developed software to measure cardia circumference from static endoscopic images. Our aims were to validate the software and to quantify cardia circumference along the spectrum of GERD.

METHODS

Software-based measurements were compared with actual measurements in animal and mechanical models. A retrospective review of an endoscopic database and patient charts produced 273 subjects, grouped as follows: controls, GERD, < or = 3-cm Barrett's esophagus, or > 3-cm Barrett's esophagus. A blinded abstractor measured cardia circumference by using images from the database.

RESULTS

Software and actual measurements correlated closely and were reproducible among observers. Median cardia circumference for each group was the following: control, 31.8 mm; GERD, 37.8 mm; < or = 3-cm Barrett's esophagus, 38.4 mm; and > 3-cm Barrett's esophagus, 45.0 mm (p < 0.001). By using 34.3 mm as a cutoff, cardia circumference was 85.3% sensitive and 89.6% specific for the diagnosis of GERD.

CONCLUSIONS

There was a direct relationship between cardia circumference and the presence of GERD. This finding augments our understanding of the anatomic contributions of the esophagogastric junction in the pathogenesis of GERD. Cardia measurement may prove to be a useful diagnostic tool.

Acid perfusion test: a useful test for evaluating esophageal acid sensitivity

The acid perfusion test (APT) is a test of esophageal acid sensitivity. In gastroesophageal reflux disease (GERD), the APT has largely been superseded by indexes derived from 24-hr esophageal pH monitoring: symptom index (SI), symptom sensitivity index (SSI), and symptom association probability (SAP). To evaluate the role of APT in patients with GERD we compared values of SI, SSI, and SAP in 126 APT+ and 146 APT- patients. Median values for SI, SSI, and SAP were higher in the APT+ compared with the APT- group (P < 0.001). More patients had a positive SI, SSI, and SAP in the APT+ compared with the APT- group (SI, P < 0.0001; SSI and SAP, P < 0.001). Patients with a negative APT were unlikely to have symptoms caused by acid reflux (negative predictive value, 86%). APT may be useful in detecting acid sensitivity in patients who do not report symptoms on 24-hr esophageal pH monitoring.

Gastroesophageal reflux: a potential asthma trigger

Gastroesophageal reflux (GER) is a potential trigger of asthma. Approximately 77% of asthmatics report heartburn. GER is a risk factor for asthma-related hospitalization and oral steroid burst use. Asthmatics may be predisposed to GER development because of a high prevalence of hiatal hernia and autonomic dysregulation and an increased pressure gradient between the abdominal cavity and the thorax, over-riding the lower esophageal sphincter pressure barrier. Asthma medications may potentiate GER. Potential mechanisms of esophageal acid-induced bronchoconstriction include a vagally mediated reflex, local axonal reflexes, heightened bronchial reactivity, and microaspiration, all resulting in neurogenic inflammation. Anti-reflux therapy improves asthma symptoms in approximately 70% of asthmatics with GER. A 3-month empiric trial of twice-daily proton pump inhibitor given 30 to 60 minutes before breakfast and dinner can identify asthmatics who have GER as a trigger of their asthma.