Inability to belch syndrome: what the gastroenterologist needs to know.

PURPOSE OF REVIEW: To review recent publications on the inability to belch syndrome. RECENT FINDINGS: Five recent retrospective case series indicate that the inability to belch syndrome usually starts in early childhood and is often accompanied by gurgling noises in the chest, pain in the chest or upper abdomen, bloating, and excessive flatulence. Currently, the vast majority of patients who have been identified with inability to belch have self-diagnosed the syndrome on the basis of information available on the internet. A favorable response to injection of botulinum toxin in the cricopharyngeus muscle is regarded as confirmation of the diagnosis. In a mechanistic study in eight patients, absence of reflexogenic relaxation of the upper esophageal sphincter upon rapid gaseous esophageal distension was confirmed to play a pivotal role in the pathogenesis of the syndrome. SUMMARY: The inability to belch syndrome, caused by failure of the upper esophageal sphincter to relax when the esophageal body is distended, clearly exists and may not be as rare as thought hitherto. However, overdiagnosis is also likely to occur because the diagnosis is usually made on the basis of symptoms only. The efficacy of botulinum toxin injection in the upper sphincter needs to be assessed in double-blind placebo-controlled studies.

Abelchia: inability to belch/burp-a new disorder? Retrograde cricopharyngeal dysfunction (RCPD).

CASE SERIES: This is retrospective case series involving 72 patients who presented with symptoms associated with inability to burp. The following symptoms was described by almost all the patients; retrosternal pain after eating or drinking, bloating feeling in the stomach, gurgling noise in the throat, excessive flatulence. These symptoms are worse with fizzy/carbonated drinks and beer. A full clinical history and examination plus endoscopic and in some cases barium a swallow radiological investigation was done. PROCEDURE: The surgery was performed under a general anaesthesia for all cases. Suspension pharyngoscopy in supine position using a Weerda diverticuloscope to identify the cricopharyngeal bar muscle. High dose of botulinum toxin A (botox) 100 iu was injected into the cricopharynxgeus muscle under a general anaesthesia. RESULTS: A total of 72 patients were diagnosed and undergone surgery between November 2016 and December 2020. There were 50 male and 22 female patients. Their average age was 30 (range 18-68 years old). All patients were able to burp again within first 4 weeks of the injection. This persisted even after the Botox worn off beyond the 3 months in 96% of cases. The average follow-up was 24 months post injection with longest follow-up 48 months (range 1-48 months). CONCLUSION: The author reported a new condition of inability to burp due to failure of the cricopharyngeal sphincter to relax spontaneously and outcome of treatment using botulinum toxin A injection into the cricopharyngeus muscle. It is expected that the paralysing action of botulinum toxin injection last approximately 3 months. However, this group of patients seem to be cured even after the effect of the botox is worn off. The author therefore postulated that there might me some neural dysfunction that inhibits the brain to send signals to the cricopharyngeal sphincter to initiate burping. Once burping is re-established with the help of botox injection, spontaneous burping seems to occur and sustained even after the botox is worn off.

ESNM/ANMS consensus paper: Diagnosis and management of refractory gastro-esophageal reflux disease.

Up to 40% of patients with symptoms suspicious of gastroesophageal reflux disease (GERD) do not respond completely to proton pump inhibitor (PPI) therapy. The term "refractory GERD" has been used loosely in the literature. A distinction should be made between refractory symptoms (ie, symptoms may or may not be GERD-related), refractory GERD symptoms (ie, persisting symptoms in patients with proven GERD, regardless of relationship to ongoing reflux), and refractory GERD (ie, objective evidence of GERD despite adequate medical management). The present ESNM/ANMS consensus paper proposes use the term "refractory GERD symptoms" only in patients with persisting symptoms and previously proven GERD by either endoscopy or esophageal pH monitoring. Even in this context, symptoms may or may not be reflux related. Objective evaluation, including endoscopy and esophageal physiologic testing, is requisite to provide insights into mechanisms of symptom generation and evidence of true refractory GERD. Some patients may have true ongoing refractory acid or weakly acidic reflux despite PPIs, while others have no evidence of ongoing reflux, and yet others have functional esophageal disorders (overlapping with proven GERD confirmed off therapy). In this context, attention should also be paid to supragastric belching and rumination syndrome, which may be important contributors to refractory symptoms.

Responses to gastric gas in patients with functional gastrointestinal disorders.

BACKGROUND: Gas-related abdominal symptoms are common in patients with functional gut disorders, but the responses to cope with the large volumes of gas that enter daily into the stomach have not been studied in detail. Our aim was to evaluate transit and tolerance of gastric gas in patients with functional gastrointestinal disorders. METHODS: In eight healthy volunteers and 24 patients with functional gut disorders (eight functional dyspepsia, eight belching disorder, and eight functional bloating) 1500 ml of a gas mixture were infused into the stomach at 25 ml/min. Belching, rectal gas evacuation, and abdominal perception were continuously recorded for 90 minutes. KEY RESULTS: Healthy subjects expelled the infused gas per rectum (1614 ± 73 ml), with a small rise in epigastric perception (score increment 1.0 ± 0.4) and virtually no belching (1 ± 1 belches). Patients with functional dyspepsia had a hypersensitive response to gastric gas, with a significant rise in epigastric perception (score increment 2.5 ± 0.6; P = .045), a transient delay in rectal gas evacuation and similar belching as healthy controls. Patients with belching disorders responded to gastric gas with continuous belches (33 ± 13 belches; P = .002), low epigastric perception, and a small reduction in rectal gas evacuation. Patients with functional bloating exhibited a slow transit response, with reduced rectal gas evacuation (1017 ± 145 ml; P = .002) and abdominal symptoms (score increment 2.5 ± 0.7), but without compensatory belching. CONCLUSIONS AND INFERENCES: Different pathophysiological mechanisms underlay specific adaptive responses to gastric gas in patients with different functional gut disorders. Therapeutic interventions for gas-related abdominal symptoms should be addressed towards these specific pathophysiological disturbances.

Evaluation and Validation of the Modified Reflux Symptom Questionnaire-Electronic Diary in Patients With Persistent Gastroesophageal Reflux Disease.

OBJECTIVES: This study aimed to examine the validity of the modified Reflux Symptom Questionnaire-electronic Diary (mRESQ-eD) through patient input and psychometric testing of the questionnaire to support use in clinical trials in patients with persistent gastroesophageal reflux disease (GERD) and in accordance with Food and Drug Administration guidance on patient-reported outcome instruments. METHODS: Cognitive interviews were conducted with patients (n = 30) to evaluate the interpretability and content validity of draft mRESQ-eD items. Patient data from a phase 2b clinical study (ClinicalTrials.gov identifier: NCT02637557) on persistent GERD served to aid in the construction of weekly scores for heartburn severity, regurgitation severity, and total GERD severity. These scores' psychometric properties were also evaluated. RESULTS: Minor modifications were made to the draft mRESQ-eD based on patient feedback to improve interpretability and clarity of the instrument. Psychometric analysis suggested that an 8-item version of the mRESQ-eD was best suited to the clinical data. The internal consistency was found to be high (Coefficient ω = 0.95). Retest reliability and convergent validity were strong for a heartburn weekly severity score, regurgitation weekly severity score, and total GERD severity score. DISCUSSION: The final 8-item mRESQ-eD is a reliable and valid instrument with good psychometric properties for use in clinical trials in patients with persistent GERD. The mRESQ-eD may be considered for inclusion in clinical trials for persistent GERD and potentially positioned, in consultation with Food and Drug Administration, as endpoints to characterize treatment benefit.

A Rare Case Involving the Inability to Belch.

A 17-year-old girl was referred to our hospital with an inability to belch, while experiencing chest gurgling noises, and severe abdominal bloating. She reported having these symptoms all her life. A timed barium esophagogram revealed a moderate amount of bubbles in the esophagus and gastric fundus, which significantly increased after the examination. High resolution manometry revealed that the basal upper esophageal sphincter pressure increased with a rise in the cervical esophageal pressure. A pathological inability to belch is rare; at present, no specific name exists to describe the disorder. Further research is needed in this unexplored field.

Characterization and mechanisms of the supragastric belch in the cat.

A response in which a belch occurs without gastric involvement, i.e., the supragastric belch (SGB), has been characterized in humans. The aims of this study were to determine whether animals have an SGB and, if so, to determine its mechanisms. Studies were conducted in decerebrate cats (n = 30) with electromyographic electrodes on hyoid, pharyngeal, esophageal, and diaphragm muscles. The effects of distending different regions of the esophagus in different manners using a balloon were quantified to determine the most appropriate stimulus for activating the cat SGB. The effects of esophageal perfusion of lidocaine (n = 3), vagus nerve transection (n = 3), or esophageal acidification (n = 5) on activation of the SGB were determined. Rapid large distensions of the thoracic esophagus best activated responses similar to the human SGB, i.e., rapid inhalation followed by a belch. The rapid inhalation was associated with activation of hiatal fibers and the belch with activation of dome fibers of the diaphragm. The rapid inhalation response was independent of the belch response. Lidocaine perfusion of the esophagus blocked the belch response without blocking the rapid inhalation, HCl perfusion sensitized the esophagus to activation of both the rapid inhalation and the belch response, and vagotomy blocked both responses. We conclude that the cat has an SGB that is composed of two independent reflex responses, i.e., rapid inhalation and belch, that are mediated by the vagus nerves and tension/mucosal receptors of the esophagus and sensitized by esophageal acid exposure. We hypothesize that the SGB is a learned voluntarily activated reflex response.NEW & NOTEWORTHY Rapid strong distension of the thoracic esophagus activates rapid inhalation followed by a belch, which is the sequence of responses that compose the human supragastric belch (SGB). The rapid inhalation and belch phases of the cat SGB are activated by hiatal and dome fibers of the diaphragm, respectively, and are mediated by the vagus nerves and tension/mucosal receptors of the esophagus and sensitized by esophageal acid exposure. There are many similarities between the cat and human SGB.

Gas swallow during meals in patients with excessive belching.

BACKGROUND: Swallowed gas is an important source of abdominal gas, and aerophagia is often believed as a putative cause of gas-related abdominal symptoms. However, altered gas-swallow during meals has not been demonstrated. Our aim was to characterize the number of gas swallows during meals in patients complaining of excessive belching and gaseousness and a control group without abdominal symptoms during a 24-h period. METHODS: A 24-h pH-impedance monitoring was performed in 10 patients with excessive belching, and 11 patients without digestive symptoms or reflux in the pH-impedance study. During the study, patients followed their daily routine and customary meals, without any specific limitation. In each patient the number and content of swallows and belches were analyzed. KEY RESULTS: Total meal periods were similar in controls (75±26 min) and patients (79±21 min; P=.339), but the number of gaseous swallows was greater in patients (114±13 swallows) than controls (71±8 swallows; P=.007), due to a greater frequency of gaseous swallows during meals (15±2 swallows/10 min vs 10±1 swallows/10 min, respectively; P=.008). During the 24-h study period, 66±13 belches were recorded in patients, but only 13±3 belches in controls (P<.001), mainly gastric belches (80±4% and 92±2% of belches, patients, and controls, respectively) which showed a good correlation with the number of gaseous swallows performed during meals (r=.756; P=.011). CONCLUSION AND INFERENCES: Gas is frequently swallowed during meals. Patients complaining of excessive belching have a different swallow pattern during meals, with an increased ingestion of gas that correlates with increased gastric belching events.

Esophageal Impedance Monitoring: Clinical Pearls and Pitfalls.

The development of intraluminal esophageal impedance monitoring has improved our ability to detect and measure gastroesophageal reflux without dependence on acid content. This ability to detect previously unrecognized weak or nonacid reflux episodes has had important clinical implications in the diagnosis and management of gastroesophageal reflux disease (GERD). In addition, with the ability to assess bolus transit within the esophageal lumen, impedance monitoring has enhanced the recognition and characterization of esophageal motility disorders in patients with nonobstructive dysphagia. The assessment of the intraluminal movement of gas and liquid has also been proven to be of diagnostic value in conditions such as rumination syndrome and excessive belching. Further, alternative applications of impedance monitoring, such as the measurement of mucosal impedance, have provided novel insights into assessing esophageal mucosal integrity changes as a consequence of inflammatory change. Future applications for esophageal impedance monitoring also hold promise in esophageal conditions other than GERD. However, despite all of the clinical benefits afforded by esophageal impedance monitoring, important clinical and technical shortcomings limit its diagnostic value and must be considered when interpreting study results. Overinterpretation of studies or application of impedance monitoring in patients can have deleterious clinical implications. This review will highlight the clinical benefits and limitations of esophageal impedance monitoring and provide clinical pearls and pitfalls associated with this technology.

Changes in patients' symptoms and gastric emptying after Helicobacter pylori treatment.

AIM: To investigate the changes in clinical symptoms and gastric emptying and their association in functional dyspepsia (FD) patients. METHODS: Seventy FD patients were enrolled and divided into 2 groups Helicobacter pylori (H. pylori)-negative group (28 patients), and H. pylori-positive group (42 patients). Patients in the H. pylori-positive group were further randomly divided into groups: H. pylori-treatment group (21 patients) and conventional treatment group (21 patients). Seventy two healthy subjects were selected as the control group. The proximal and distal stomach area was measured by ultrasound immediately after patients took the test meal, and at 20, 40, 60 and 90 min; then, gastric half-emptying time was calculated. The incidence of symptoms and gastric half-emptying time between the FD and control groups were compared. The H. pylori-negative and conventional treatment groups were given conventional treatment: domperidone 0.6 mg/(kg/d) for 1 mo. The H. pylori-treatment group was given H. pylori eradication treatment + conventional treatment: lansoprazole 30 mg once daily, clarithromycin 0.5 g twice daily and amoxicillin 1.0 g twice daily for 1 wk, then domperidone 0.6 mg/(kg/d) for 1 mo. The incidence of symptoms and gastric emptying were compared between the FD and control groups. The relationship between dyspeptic symptoms and gastric half-emptying time in the FD and control groups were analyzed. Then total symptom scores before and after treatment and gastric half-emptying time were compared among the 3 groups. RESULTS: The incidence of abdominal pain, epigastric burning sensation, abdominal distension, nausea, belching, and early satiety symptoms in the FD group were significantly higher than in the control group (50.0% vs 20.8%; 37.1% vs 12.5%; 78.6% vs 44.4%; 45.7% vs 22.2%; 52.9% vs 15.3%; 57.1% vs 19.4%; all P < 0.05). The gastric half-emptying times of the proximal end, distal end, and the whole stomach in the FD group were slower than in the control group (93.7 ± 26.2 vs 72.0 ± 14.3; 102.2 ± 26.4 vs 87.5 ± 18.2; 102.1 ± 28.6 vs 78.3 ± 14.1; all P < 0.05). Abdominal distension, belching and early satiety had an effect on distal gastric half-emptying time (P < 0.05). Abdominal distension and abdominal pain had an effect on the gastric half-emptying time of the whole stomach (P < 0.05). All were risk factors (odds ratio > 1). The total symptom score of the 3 groups after treatment was lower than before treatment (P < 0.05). Total symptom scores after treatment in the H. pylori-treatment group and H. pylori-negative group were lower than in the conventional treatment group (5.15 ± 2.27 vs 7.02 ± 3.04, 4.93 ± 3.22 vs 7.02 ± 3.04, All P < 0.05). The gastric half-emptying times of the proximal end, distal end, and the whole stomach in the H. pylori-negative and H. pylori-treatment groups were shorter than in the conventional treatment group (P < 0.05). CONCLUSION: FD patients have delayed gastric emptying. H. pylori infection treatment helps to improve symptoms of dyspepsia and is a reasonable choice for treatment in clinical practice.

Belching After Biliary Pancreatitis and Laparoscopic Cholecystectomy.

INTRODUCTION: Belching is often reported symptom. It is rarely an isolated disorder and mainly occurs within various gastroduodenal diseases. AIM: The aim is to show the great breadth of clinical symptoms of postcholecystectomy syndrome which should have a multidisciplinary therapeutic approach taking into account all aspects of patient's life. CASE REPORT: We report a case of excessive belching within postcholecystectomy syndrome which disturbs the general psycho-physical condition of the patient, with symptoms of depression and anxiety, and social isolation, which significantly reduces the quality of his life.

Supragastric belching.

PURPOSE OF REVIEW: Supragastric belching has recently gained recognition as a belching disorder of behavioral origin that can be accurately diagnosed on esophageal impedance monitoring. Its contribution to numerous other gastrointestinal disorders is beginning to be appreciated. Improved knowledge of its pathophysiology has enabled identification of therapeutic goals, some of which have been subject to formal study and demonstrated good outcomes. This review sets out to present and discuss new findings related to the improved understanding of the relationship between supragastric belching and other gastrointestinal disorders, as well as fresh concepts in terms of management. RECENT FINDINGS: Supragastric belching is now shown to be associated with globus, as well as reflux symptoms in proton pump inhibitor nonresponders. Patients with supragastric belching experience higher frequency of belching events if they have concurrent esophageal hypomotility. Gum chewing and sleeve gastrectomy have no impact on supragastric belching. Pediatric studies suggest an overlap with aerophagia that is not observed in adults. Successful treatments trialed recently include psychoeducation and behavioral therapy delivered by a health psychologist with expertise in gastroenterology. SUMMARY: With the foreseeable increase in recognition and diagnosis of pathological supragastric belching, there is a clear need to better understand its pathophysiology, especially in terms of its emerging importance in relation to other gastrointestinal disorders. Further study is justified to uncover additional therapeutic options for this benign but disabling condition.

Impact of laparoscopic antireflux surgery on belching in pediatric GERD patients.

BACKGROUND: Laparoscopic antireflux surgery (LARS) is a well-established treatment option for children with proton pomp inhibitor (PPI)-resistant gastroesophageal reflux disease (GERD). Besides preventing reflux of gastric fluid and solid content, LARS may also impair the ability of the stomach to vent intragastric air (i.e. gastric belching) and induce gas-related complications, such as bloating and/or hyperflatulence. Furthermore, it was previously hypothesized that LARS induces a behavioral type of belching, not originating from the stomach, called supragastric belching. The aim of this study was to objectively evaluate the impact of LARS on gastric (GB) and supragastric belching (SGB) in children with GERD. METHODS: We performed a prospective, Dutch multicenter cohort study including 25 patients (12 males, median age 6 (range 2-18) years) with PPI-resistant GERD who were scheduled for LARS. Twenty-four-hour multichannel intraluminal impedance pH monitoring (MII-pH monitoring) was performed before and 3 months after fundoplication. Impedance pH tracings were analyzed for reflux episodes and GBs and SGBs. KEY RESULTS: LARS reduced acid exposure time from 8.5% (6.0-16.2%) to 0.8% (0.2-2.8%), p < 0.001. The number of GBs also significantly decreased after LARS (59 [43-77] VS 5 [2-12], p < 0.001). The number of air swallows remained unchanged after LARS. SGBs were infrequent before LARS with no change in the number of SGB observed after the procedure. Postoperative belching symptoms were associated with GBs, not with SGBs. CONCLUSION & INFERENCES: LARS significantly reduces the number of GBs in children with GERD, whereas the number of air swallows remains unchanged. Postoperative symptomatic belching is associated with GBs, but not with SGBs. These findings suggest that LARS does not induce the occurrence of SGBs in children, but longer follow-up is required.

Supragastric belch may be related to globus symptom - a prospective clinical study.

BACKGROUND: The etiology of globus is poorly understood. It is controversial, whether gastroesophageal reflux disease (GERD) has a role in globus. To investigate the possible esophageal background of this symptom, we performed transnasal esophagoscopy (TNE), high-resolution manometry (HRM), and 24-h multichannel intraluminal impedance (MII) and pH monitoring on globus patients. METHODS: Thirty consecutive patients were referred to Helsinki University Hospital, Department of Otorhinolaryngology - Head and Neck Surgery for treatment of globus; 24 consecutive patients with difficult reflux symptoms from the Department of Surgery served as controls. We compared the results of the patient groups in endoscopies, HRM, and 24-h MII-pH monitoring. KEY RESULTS: In MII monitoring, globus patients had supragastric belch (6/20, 30% vs 1/24, 4%; p = 0.038) more often than controls. Total reflux time was higher in controls (p = 0.004), and they had more acid reflux events (p = 0.002) in MII, but between groups, the number of non-acid reflux events was similar. In pH monitoring, DeMeester score and total pH <4 time were higher in controls (P < 0.001). In HRM, the upper esophageal sphincter (UES) mean basal and residual pressures did not differ. CONCLUSIONS & INFERENCES: Supragastric belch was more common in globus patients, suggesting the possible role of this condition in globus sensation. However, globus patients in this series had no acid or non-acid GERD or elevated UES pressure.

The Physiology of Eructation.

Eructation is composed of three independent phases: gas escape, upper barrier elimination, and gas transport phases. The gas escape phase is the gastro-LES inhibitory reflex that causes transient relaxation of the lower esophageal sphincter, which is activated by distension of stretch receptors of the proximal stomach. The upper barrier elimination phase is the transient relaxation of the upper esophageal sphincter along with airway protection. This phase is activated by stimulation of rapidly adapting mechanoreceptors of the esophageal mucosa. The gas transport phase is esophageal reverse peristalsis mediated by elementary reflexes, and it is theorized that this phase is activated by serosal rapidly adapting tension receptors. Alteration of the receptors which activate the upper barrier elimination phase of eructation by gastro-esophageal reflux of acid may in part contribute to the development of supra-esophageal reflux disease.

Belching during gastroscopy and its association with gastroesophageal reflux disease.

Belching may result from transient lower esophageal sphincter relaxation; therefore, it has been proposed that belching may be a manifestation of gastroesophageal reflux disease (GERD). This study was conducted to investigate the frequency of belching during esophagogastroduodenoscopy (EGD) and its association with GERD. A retrospective review was performed on prospectively collected clinical and endoscopic data from 404 subjects who underwent EGD without sedation from December 2012 to May 2013 in a training hospital in Korea. All detectable belching events during endoscopy were counted. Frequency and severity of belching events were compared between the group with and without GERD using an ordinal logistic regression model. There were 145 GERD patients (26 erosive reflux disease and 119 nonerosive reflux disease [NERD]). In the multivariable analysis, GERD was significantly associated with a higher frequency of belching events (odds ratio = 6.59, P < 0.001). Central obesity, female, and younger age were also risk factors for frequent belching during EGD. Subgroup analyses were performed in subjects without erosive reflux disease (n = 378) and NERD (n = 293). NERD was also a predictive factor for frequent belching during EGD (odds ratio = 6.61, P < 0.001), and the frequency of belching was significantly correlated with GERD severity according to the Los Angeles classification (P < 0.05). Frequent belching during EGD was associated with GERD, including NERD. Future research should focus on its adjuvant role in the diagnosis of GERD/NERD and the necessity for applying differentiated endoscopy strategies for GERD patients, leading to less discomfort during EGD in patients at risk for intolerability.

Help from habit reversal for supragastric belching.

Supragastric belching differs from common gastric belching. It can be detected by 24-hour intra-esophageal impedance monitoring. Belching is seldom the only symptom: reflux symptom is present in 95% and dysphagia in 65% of the patients. In supragastric belching, the air does not come from the stomach but instead from the esophagus. Belching is caused by the patient him/herself swallowing air into the esophagus. This voluntary but unconscious symptom is treated by therapy in which explaining the mechanism of belching for the patient and learning of correct diaphragmatic breathing technique play a central role. Habit reversal is utilized for teaching the patient to react correctly to preemptive symptoms.

Belching, regurgitation, chest tightness and dyspnea: not gastroesophageal reflux disease but asthma.

Belching is a common symptom of gastroesophageal reflux disease. If the symptoms are not relieved after anti-reflux treatment, another etiology should be considered. Here, we report a case of a 43-year-old man who presented with belching, regurgitation, chest tightness and dyspnea for 18 mo, which became gradually more severe. Gastroscopic examination suggested superficial gastritis. Twenty-four-hour esophageal pH monitoring showed that the Demeester score was 11.4, in the normal range. High-resolution manometry showed that integrated relaxation pressure and intrabolus pressure were higher than normal (20 mmHg and 22.4 mmHg, respectively), indicating gastroesophageal junction outflow tract obstruction. Pulmonary function test showed severe obstructive ventilation dysfunction [forced expiratory volume in 1 second (FEV1)/forced vital capacity 32%, FEV1 was 1.21 L, occupying 35% predicted value after salbuterol inhalation], and positive bronchial dilation test (∆FEV1 260 mL, ∆FEV1% 27%). Skin prick test showed Dermatophagoides farinae (++), house dust mite (++++), and shrimp protein (++). Fractional exhaled nitric oxide measurement was 76 ppb. All the symptoms were alleviated completely and pulmonary function increased after combination therapy with corticosteroids and long-acting ß2-agonist. Bronchial asthma was eventually diagnosed by laboratory tests and the effect of anti-asthmatic treatment, therefore, physicians, especially the Gastrointestinal physicians, should pay attention to the belching symptoms of asthma.