Dilated intercellular space diameter as marker of reflux-related mucosal injury in children with chronic cough and gastro-oesophageal reflux disease

Proximal esophageal impedance baseline increases the yield of impedance-pH and is associated with response to PPIs in chronic cough patients

BACKGROUND

Chronic cough significantly impairs the quality of life. Although various studies focused on MNBI as assessed in the distal esophagus, scarce data are available on the clinical value of proximal measurements.

AIM

To investigate the role of proximal MNBI in the workup of patients with chronic cough and its ability to predict PPI response.

METHODS

Demographic, clinical, endoscopy findings, impedance-pH and HRM tracings from consecutive cough patients were evaluated. MNBI was calculated at proximal and distal esophagus.

RESULTS

One hundred and sixty four patients were included. In addition to traditional variables, when considering also the PSPW index or MNBI at 3 cm or 15 cm, the proportion of patients with pathological impedance-pH monitoring significantly increased. 70/164 patients were responders, while 94 (57.3%) were non-responder to double PPI dose (p < 0.05). Patients with pathologic MNBI at 3 cm and/or 15 cm as well as those with pathologic PSPW index were characterized by a significantly higher proportion of responders than that observed among patients with normal impedance-pH variables (p < 0.001). The proportion of responders with pathological MNBI at 15 cm was significantly higher than the proportion of responders with pathological MNBI at 3 cm (82.8% vs. 64.3%, p < 0.05). At multivariable model, pathological MNBI at both 3 cm and 15 cm as well as PSPW index were associated with PPI responsiveness. The strongest association with PPI response was observed for MNBI at 15 cm.

CONCLUSIONS

The assessment of MNBI at proximal esophagus increases the diagnostic yield of impedance-pH monitoring and may represent a useful predictor of PPI responsiveness in the cumbersome clinical setting of suspected reflux-related cough.

Application of electron microscopy in gastroenterology

Electron microscopy has long been used in research in the fields of life sciences and materials sciences. Transmission and scanning electron microscopy and energy-dispersive X-ray spectroscopy (EDX) analyses have also been performed in the field of gastroenterology. Electron microscopy and EDX enable (1) Observation of ultrastructural differences in esophageal epithelial cells in patients with gastroesophageal reflux and eosinophilic esophagitis; (2) Detection of lanthanum deposition in the stomach and duodenum; (3) Ultrastructural and elemental analyses of enteroliths and bezoars; (4) Detection and characterization of microorganisms in the gastrointestinal tract; (5) Diagnosis of gastrointestinal tumors with neuroendocrine differentiation; and (6) Analysis of gold nanoparticles potentially used in endoscopic photodynamic therapy. This review aims to foster a better understanding of electron microscopy applications by reviewing relevant clinical studies, basic research findings, and the state of current research carried out in gastroenterology science.

Pathophysiology of Pediatric Gastroesophageal Reflux Disease: Similarities and Differences With Adults

Gastroesophageal reflux (GOR) is defined as "the passage of gastric contents into the esophagus with or without regurgitation and vomiting" and gastroesophageal reflux disease (GORD) is defined "when GOR leads to troublesome symptoms affecting the daily functioning and/or complications." This definition was first developed in 2006 by the Montreal consensus group (1) and later on adopted by pediatric gastroenterology societies such as ESPGHAN and NASPGHAN in 2009 (2). The definition of gastroesophageal reflux reveals little about its pathophysiology and is focused on symptomatology. In this way, it acts as an umbrella term for the multifactorial causes of the disease and the various phenotypes encountered; from functional heartburn to hypersensitive esophagus and nonerosive reflux disease, to erosive esophagitis and Barrett's esophagus. This article is devoted to the pathophysiology of pediatric GORD in comparison to adult GORD and is divided in 2 parts. In the first part, we will systematically describe the different mechanisms for the generation and clearance of reflux events, while on the second part we will discuss the mechanisms involved in symptoms generation. Finally, we will discuss the similarities and differences between pediatric and adult GORD.

The Results From Up-Front Esophageal Testing Predict Proton Pump Inhibitor Response in Patients With Chronic Cough

INTRODUCTION

The clinical management of chronic cough patients is challenging, and their response to proton pump inhibitors (PPIs) is considered as unsatisfactory. Few data concerning the association between impedance-pH variables and PPI response in these patients are available. Mean nocturnal baseline impedance (MNBI) and postreflux swallow-induced peristaltic wave (PSPW) index increase the diagnostic yield of impedance-pH in gastroesophageal reflux disease.

METHODS

Demographic, clinical, and endoscopy findings; impedance-pH; and high-resolution manometry tracings from consecutive patients assessed for cough were evaluated. Univariable and multivariable regression models were generated to evaluate the association between impedance-pH and high-resolution manometry findings, endoscopic and clinical characteristics, and PPI response.

RESULTS

A total of 178 patients were included. Eighty-four of 178 cough patients (47.2%) displayed grade C-D erosive esophagitis or were characterized by a pathological acid exposure time (AET) and/or positive symptom association probability/symptom index. When also considering MNBI and PSPW, 135 of 178 patients (75.8%) were characterized by the evidence of reflux disease (P < 0.001). Eighty patients (44.9%) had cough responding to PPIs, whereas 98 (55.1%) were nonresponders (P = 0.071). At the receiver operating characteristic analysis, both PSPW index and MNBI were associated to PPI responsiveness. MNBI and PSPW index showed higher sensitivity in predicting PPI response compared with AET and symptom association probability/symptom index. The area under the curves of MNBI and PSPW index were significantly higher than that of AET (P < 0.01 for both comparisons). When patients were stratified according to AET and excluding those with erosive esophagitis, pathological MNBI or PSPW index, hiatal hernia, and hypomotility features were associated to PPI response in all groups.

DISCUSSION

Our results demonstrate the usefulness of an up-front esophageal testing in discriminating reflux-related cough patients and predicting PPI response.

Esophageal Impedance-pH Monitoring and Pharyngeal pH Monitoring in the Diagnosis of Extraesophageal Reflux in Children

Various clinical symptoms are attributed to extraesophageal reflux disease (EERD). Multichannel intraluminal impedance-pH monitoring (MII-pH) is considered to correlate symptoms with acid and nonacid gastroesophageal reflux (GER) events. Pharyngeal pH monitoring (Dx-pH) is considered to correlate the decrease in the pH level in the oropharynx with reported symptoms and to diagnose supraesophageal reflux. We aimed to assess the correlation between acid reflux episodes recorded by Dx-pH and GER detected via MII-pH in children with suspected EERD. The study enrolled 23 consecutive children (15 boys and 8 girls; median age 8.25 [range 3-16.5] years) with suspected EERD. MII-pH and Dx-pH were conducted concurrently in all patients. A total of 1228 reflux episodes were recorded by MII-pH. With the antimonic sensor placed inside the impedance probe, 1272 pH-only reflux episodes were recorded. Of these, 977 (76.81%) were associated with a retrograde bolus transit. Regarding GER, 630 full-column episodes extended to the most proximal pair of impedance sensors; 500 (83.33%) demonstrated an acidic character. The following acid reflux numbers were determined by the Dx-pH system: for pH < 4, n = 126; pH < 4.5, n = 136; pH < 5, n = 167; and pH < 5.5, n = 304, and for a decrease in pH > 10% relative to the baseline, n = 324. There was no significant correlation between the number of pharyngeal reflux episodes detected by Dx-pH and that of GERs identified by MII-pH. The proportion of oropharyngeal pH events that were temporally related to a GER episode increased with the extended pH criteria. The highest proportion was observed for a pH decrease of ≥10% from the baseline and did not exceed 5.2%. The application of the extended pH criteria in the Dx-pH system resulted in an increase in the number of diagnosed laryngopharyngeal refluxes; most were not temporally associated with GER episodes confirmed by MII-pH. Thus, the efficacy of the exclusive application of Dx-pH for supraesophageal gastric reflux diagnosis is uncertain.

Importance of diagnosis and management of psychological disorders in patients with refractory gastroesophageal reflux disease

Psychological factors are closely related to the pathogenesis of gastroesophageal reflux disease, irritable bowel syndrome, functional dyspepsia, and other gastrointestinal diseases. It has been widely accepted that psychological factors play a very important role in refractory gastroesophageal reflux disease (RGERD). This article reviews the role of psychological factors in the epidemiology, pathogenesis, assessment, and management of RGERD.

An updated review on gastro-esophageal reflux in pediatrics

Comprehensive guidelines for the diagnosis and management of gastro-esophageal reflux (GER) and GER disease (GERD) were developed by the European and North American Societies for Pediatric Gastroenterology, Hepatology and Nutrition. GERD is reflux associated with troublesome symptoms or complications. The recognition of GER and GERD is relevant to implement best management practices. A conservative management is indicated in infants with uncomplicated physiologic reflux. Children with GERD may benefit from further evaluation and treatment. Since the publications of the European and North American Societies for Pediatric Gastroenterology, Hepatology and Nutrition guidelines in 2009, no important novelties in drug treatment have been reported. Innovations are mainly restricted to the management of regurgitation in infants. During the last 5 years, pros and cons of multichannel intraluminal impedance have been highlighted. However, overall 'not much has changed' in the diagnosis and management of GER and GERD in infants and children.

Respiratory disease and the oesophagus: reflux, reflexes and microaspiration

Gastro-oesophageal reflux is associated with a wide range of respiratory disorders, including asthma, isolated chronic cough, idiopathic pulmonary fibrosis, chronic obstructive pulmonary disease and cystic fibrosis. Reflux can be substantial and reach the proximal margins of the oesophagus in some individuals with specific pulmonary diseases, suggesting that this association is more than a coincidence. Proximal oesophageal reflux in particular has led to concern that microaspiration might have an important, possibly even causal, role in respiratory disease. Interestingly, reflux is not always accompanied by typical reflux symptoms, such as heartburn and/or regurgitation, leading many clinicians to empirically treat for possible gastro-oesophageal reflux. Indeed, costs associated with use of acid suppressants in pulmonary disease far outweigh those in typical GERD, despite little evidence of therapeutic benefit in clinical trials. This Review comprehensively examines the possible mechanisms that might link pulmonary disease and oesophageal reflux, highlighting the gaps in current knowledge and limitations of previous research, and helping to shed light on the frequent failure of antireflux treatments in pulmonary disease.

Refractory chronic cough due to gastroesophageal reflux: Definition, mechanism and management

Refractory chronic cough due to gastroesophageal reflux is a troublesome condition unresponsive to the standard medical anti-reflux therapy. Its underlying mechanisms may include incomplete acid suppression, non-acid reflux, transient lower esophageal sphincter relaxations and esophageal hypersensitivity. The diagnosis of this disorder depends on both the findings of multi-channel intraluminal impedance-pH monitoring and the subsequent intensified anti-reflux therapy. The strategies of pharmacological treatment for refractory chronic cough due to reflux include the optimization of proton pump inhibitors and add-on therapies with histamine H₂ receptor antagonists, baclofen and gabapentin. However, the further study is needed to satisfy its management.

Symptoms and diagnosis of acid vs non-acid gastroesophageal reflux induced cough

AIM: To compare the symptoms and diagnosis of acid and non-acidic gastroesophageal reflux induced cough (GERC).

METHODS: Forty patients diagnosed with GERC were collected between January 2011 and December 2013 at our hospital, including 21 cases of acid GERC (DeMeester score ≥ 12.70) and 19 cases of non-acid GERC (DeMeester score < 12.70). The clinical symptoms, gastroesophageal reflux diagnostic questionnaire (GerdQ) score, and DeMeester score were compared between the two groups.

RESULTS: The age and incidence of reflux were significantly lower in the non-acid GERC group than in the acid GERC group (χ² = 6.686, P = 0.010). There were no significant differences in the nature of cough, cough duration, frowsty bosom, history of stomach problems or complicated obstructive sleep apnea syndrome (OSAS) between the two groups (P > 0.05). Compared with the acid GERC group, the non-acid GERC group had significantly lower GerdQ score and DeMeester score (χ² = 2.337, P = 0.003), although there was no significant difference between daytime and nighttime cough (P > 0.05).

CONCLUSION: Acid and non-acid GERC differs little in terms of clinical symptoms and should be diagnosed based on comprehensive evaluation including GerdQ and DeMeester scores.