Reflux cough

Prevalence of gastroesophageal reflux disease in children with extraesophageal manifestations using combined-video, multichannel intraluminal impedance-pH study

BACKGROUND

Gastroesophageal reflux disease (GERD) might be either a cause or comorbidity in children with extraesophageal problems especially as refractory respiratory symptoms, without any best methods or criterion for diagnosing it in children.

AIM

To evaluate the prevalence of extraesophageal GERD using conventional and combined-video, multichannel intraluminal impedance-pH (MII-pH), and to propose novel diagnostic parameters.

METHODS

The study was conducted among children suspected of extraesophageal GERD at King Chulalongkorn Memorial Hospital between 2019 and 2022. The children underwent conventional and/or combined-video MII-pH. The potential parameters were assessed and receiver operating characteristic was used for the significant parameters.

RESULTS

Of 51 patients (52.9% males), aged 2.24 years were recruited. The common problems were cough, recurrent pneumonia, and hypersecretion. Using MII-pH, 35.3% of the children were diagnosed with GERD by reflux index (31.4%), total reflux events (3.9%), and symptom indices (9.8%) with higher symptom recorded in the GERD group (94 vs 171, P = 0.033). In the video monitoring group (n = 17), there were more symptoms recorded (120 vs 220, P = 0.062) and more GERD (11.8% vs 29.4%, P = 0.398) by symptom indices. Longest reflux time and mean nocturnal baseline impedance were significant parameters for diagnosis with receiver operating characteristic areas of 0.907 (P = 0.001) and 0.726 (P = 0.014).

CONCLUSION

The prevalence of extraesophageal GERD in children was not high as expected. The diagnostic yield of symptom indices increased using video monitoring. Long reflux time and mean nocturnal baseline impedance are novel parameters that should be integrated into the GERD diagnostic criteria in children.

The relationship between gastroesophageal reflux disease and recurrent wheezing in children

Gastroesophageal reflux disease occurs when gastric contents flow back into the esophagus and produce symptoms. Recurrent wheezing affects the quality of life for the patient and family. The association of gastroesophageal reflux with recurrent wheezing is suggested by different studies. The purpose of this study was to explore this relationship and to evaluate the outcome after appropriate treatment.A retrospective study on 85 children with recurrent wheezing, admitted in a pediatric gastroenterology regional center in Romania was performed. 24-hour continuous esophageal pH monitoring was used to evaluate the presence of gastroesophageal reflux and the results were interpreted using the Boix Ochoa score. All patients with positive score received treatment with proton pump inhibitors and they were evaluated again after 2 months.Gastroesophageal reflux was present in 71 children (83.5%), while 14 (16.5%) had a negative score, with a statistic significance (χ2 = 6.88, P = .0086, 95% confidence interval). After 2 months treatment with proton pump inhibitors, the Boix Ochoa score was still positive in 15 patients (21.13%).Recurrent wheezing is a solid reason for evaluating the presence of gastroesophageal reflux by 24-hour continuous esophageal pH-metry. Adequate treatment of gastroesophageal reflux solves also the recurrent wheezing in the majority of patients.

Extraesophageal presentations of GERD: where is the science?

This article reviews the evaluation and management of patients with suspected extraesophageal manifestations of gastroesophageal reflux disease, such as asthma, chronic cough, and laryngitis, which are commonly encountered in gastroenterology practices. Otolaryngologists and gastroenterologists commonly disagree upon the underlying cause for complaints in patients with one of the suspected extraesophageal reflux syndromes. The accuracy of diagnostic tests (laryngoscopy, endoscopy, and pH- or pH-impedance monitoring) for patients with suspected extraesophageal manifestations of gastroesophageal reflux disease is suboptimal. An empiric trial of proton pump inhibitors in patients without alarm features can help some patients, but the response to therapy is variable.

Impedance-pH testing

Pharmacologic treatment of gastroesophageal reflux disease is based upon gastric acid suppression with proton pump inhibitors (PPIs). In many patients, symptoms persist despite PPI treatment. For some, ongoing symptoms may be due to nonacid reflux. Accurate measurement of nonacid reflux is not possible with conventional ambulatory pH monitoring. Impedance-pH monitoring has advanced the ability to assess gastroesophageal reflux, because, in addition to detecting acid reflux, it enables measurement of nonacid reflux. This article discusses the principles of impedance-pH monitoring, catheter characteristics and placement, interpretation of studies, and clinical uses of this form of reflux monitoring.

Respiratory and laryngeal symptoms secondary to gastro-oesophageal reflux

Gastro-oesophageal reflux may cause a range of laryngeal and respiratory symptoms. Mechanisms responsible include the proximal migration of gastric refluxate beyond the upper oesophageal sphincter causing direct irritation of the larynx and lower airway. Alternatively, refluxate entering the distal oesophagus alone may stimulate oesophageal sensory nerves and indirectly activate airway reflexes such as cough and bronchospasm. Recognising reflux as a cause for these extraoesophageal symptoms can be difficult as many patients do not have typical oesophageal symptoms (eg, heartburn) and clinical findings on laryngoscopy are not very specific. Acid suppression remains an effective treatment in the majority of patients but there is growing appreciation of the need to consider and treat non-acid and volume reflux. New opinions about the role of existing medical and surgical (laparoscopic techniques) treatment are emerging and a number of novel anti-reflux treatments are under development.

[The value of twenty-four hour intraoesophageal pH monitoring and manometry in the management of patients with upper gastrointestinal symptoms]

Functional gastroenterological examinations (intraoesophageal pH monitoring, oesophageal manometry, scintigraphy, impedance examination) play important role in the management of patients with upper gastrointestinal complaints.

PATIENTS AND METHODS

Four different cases are demonstrated where diagnose and therapy was developed by these examinations. Two patients had typical gastro-oesophageal reflux symptoms and two others had dysphagia. Intraoesophageal pH monitoring was performed by Zinetics twenty-four hour one or two channel pH catheters and oesophageal manometry was carried out by Zinetics EMC four channel catheter with water perfusion method.

CASE REPORTS

In one of the patients with typical and extraoesophageal reflux symptoms, lower oesophageal sphincter incompetency by manometry and pathological acid reflux was observed by intraoesophageal pH monitoring, respectively. Furthermore, hiatal hernia was established, peristalsis of the oesophagus proved to be preserved. Because of incomplete efficacy of proton pump inhibitor (PPI) therapy, antireflux surgery was indicated. An other patient with reflux symptoms had physiological pH monitoring and manometric values. Hypersensitive oesophagus was diagnosed and PPI therapy in double dose was applied. Both patients are symptom free up to now. Other two patients complained difficult swallowing and weight loss. Absence of lower oesophageal sphincter relaxation and hypomotility of the oesophagus was observed. After oesophageal dilatation, both patients with achalasia could easy swallow and eat.

CONCLUSIONS

Our cases confirm the importance of the twenty-four hour intraoesophageal pH monitoring and oesophageal manometry in the diagnosis of gastro-oesophageal reflux disease, non-cardiac chest pain, other extraoesophageal manifestations and dysphagia. These examinations support the decision for the adequate therapeutic strategy (conventional treatment, surgery or operation or endoscopic intervention) and are important in the follow-up of patients.

Cough and gastroesophageal reflux: insights from animal models

Chronic cough in gastroesophageal reflux disease (GERD) has been attributed to irritation of the esophagus and/or upper airways by reflux of gastric content. Animal models have provided insight into both of these putative mechanisms. In patients with chronic cough and GERD, stimuli associated with reflex in the esophagus sensitize the cough reflex. This sensitization can be reproduced in the guinea pig and is most likely mediated by the esophageal afferent nerve fibers carried by the vagus nerves. Studies in animals have identified several subtypes of vagal esophageal C-fibers that may subserve this function. The putative nociceptive vagal C-fibers in the guinea pig esophagus are stimulated by acid and express the TRPV1 and TRPA1 receptors that confer responsiveness to disparate noxious stimuli. Acute and/or chronic irritation of the upper airways by reflux may contribute to cough by stimulation and/or sensitization of the airway afferent nerves. Studies in animals have identified airway nerves that likely initiate cough due to aspirated reflux; have characterized their pharmacology; and have provided insight into changes of their sensitivity. Studies in animal models have also described the neurophysiology of reflexes that protect the airways from reflux. In conclusion, animal models provide mechanistic insight into the modulation of cough from the esophagus and the pharmacology of neural pathways mediating cough in GERD.