Gastroesophageal reflux disease and asthma in children

Gastroesophageal reflux in children: an updated review

Background

Gastroesophageal reflux is a common disorder in pediatrics. Clinicians should be familiar with the proper evaluation and management of this condition.

Objective

To provide an update on the current understanding, evaluation, and management of gastroesophageal reflux in children.

Methods

A PubMed search was performed with Clinical Queries using the key term ‘gastroesophageal reflux’. The search strategy included meta-analyses, randomized controlled trials, clinical trials, observational studies, and reviews. The search was restricted to the English literature and the pediatric age group.

Results

Regurgitation is the most frequent symptom of gastroesophageal reflux and is present in nearly all cases. Gastroesophageal reflux occurs normally in infants, is often physiological, peaks at 4 months of age, and tends to resolve with time. Gastroesophageal reflux disease occurs when gastric contents reflux into the esophagus or oropharynx and produce troublesome symptom(s) and/or complication(s). A thorough clinical history and a thorough physical examination are usually adequate for diagnosis. When the diagnosis is ambiguous, diagnostic studies may be warranted. A combined esophageal pH monitoring and multichannel intraluminal esophageal electrical impedance device is the gold standard for the diagnosis of gastroesophageal reflux disease if the diagnosis is in doubt. In the majority of cases, no treatment is necessary for gastroesophageal reflux apart from reassurance of the benign nature of the condition. Treatment options for gastroesophageal reflux disease are discussed.

Conclusion

In most cases, no treatment is necessary for gastroesophageal reflux apart from reassurance because the condition is benign and self-limiting. Thickened feedings, postural therapy, and lifestyle changes should be considered if the regurgitation is frequent and problematic. Pharmacotherapy should be considered in the treatment of more severe gastroesophageal reflux disease for patients who do not respond to conservative measures. Proton pump inhibitors are favored over H₂-receptor antagonists because of their superior efficacy. Antireflux surgery is indicated for patients with significant gastroesophageal reflux disease who are resistant to medical therapy.

Evaluation of gastro-oesophageal reflux disease in wheezy infants using 24-h oesophageal combined impedance and pH monitoring

BACKGROUND AND STUDY AIMS

Gastro-oesophageal reflux disease (GERD) is incriminated as a cause of non-asthmatic infantile wheeze. To date, no diagnostic test is considered standard for GERD-related airway reflux diagnosis. Oesophageal combined multiple channel intraluminal impedance and pH (MII-pH) monitoring is proposed to be a sensitive tool for evaluation of all GERD including infantile wheeze. We aimed to determine the GERD prevalence amongst wheezy infants in the first year of life using combined MII-pH versus pH monitoring alone and evaluate the sensitivity and specificity of objective MII-pH monitoring parameters in GERD-associated infantile wheeze diagnosis compared to those of lipid-laden macrophage index (LLMI).

PATIENTS AND METHODS

Thirty-eight wheezy infants below 1year of age were evaluated for GERD using oesophageal combined MII-pH monitoring and LLMI.

RESULTS

Totally, 60.5% of cases had abnormal MII-pH; only 7.9% of them had abnormal pH monitoring. LLMI was significantly higher in wheezy infants with abnormal MII-pH than infants with normal MII-pH monitoring (112±88 versus 70±48; P=0.036). The current definitions of abnormal MII-pH study, reflux index≥10% and distal reflux episodes≥100, had low sensitivity (23%) but high specificity (100% and 96%, respectively) in GERD-related aspiration diagnosis defined by LLMI≥100. Using ROC curves, bolus contact time≥2.4% and proximal reflux episodes≥46 had 61% and 54% sensitivity and 64% and 76% specificity, respectively, in GERD-related aspiration diagnosis.

CONCLUSION

Combined MII-pH is superior to pH monitoring in reflux-associated infantile wheeze diagnosis. Objective data including proximal reflux episodes and bolus contact time should be combined with the current parameters used in reflux-associated infantile wheeze diagnosis.

Gastro-esophageal reflux in early childhood wheezers

Wheezing is common among infants and young children due to peculiar anatomical and physiological properties of their lungs. Gastro-oesophageal reflux (GER) has been incriminated as one of the cause of non-asthmatic wheezing in this age group. The present study evaluates the magnitude of GER and its causal relationship with wheezing in early childhood. All recurrent and persistent wheezers (under two years) were investigated for GER and treated medically where tests were positive. The subjects were further profiled to identify any predictors for GER. Sixty-seven children of less than 2 years age with recurrent or persistent wheezing were evaluated for GER. Mean age of the study subjects at enrolment was 10.8 months and at onset of wheezing was 7.1 (± 3.8 S.D) months. Asthma and wheeze associated lower respiratory tract infection (WALRI) was diagnosed in about 1/3 each of the patients studied. GER studies were positive in over one-third (25/67) of cases. Forty-two percent of children who wheezed by 1 year of age had a positive GER study. Interestingly, nearly half (12/25) of the patients with an abnormal study did not have any clinical suggestion of regurgitation ("silent" GERs). The severity of wheezing was higher among those who had GER versus those who did not (p ≤ 0.048; OR: 3.2). However, only 32% patients showed significant response to anti reflux treatment alone while others had partial response. GER, therefore, is an important cause for recurrent wheezing among children less than 2 years of age, either singularly or as a co-morbidity. The study findings justify investigations for GER among early wheezers; particularly for those who have onset of symptoms by 12 months of age or those who have severe disease.

Induced Sputum Substance P in Children with Difficult-to-Treat Bronchial Asthma and Gastroesophageal Reflux: Effect of Esomeprazole Therapy

Objectives. To assess the induced sputum substance P (ISSP) levels in children having difficult-to-treat asthma (DA) with and without gastroesophageal reflux (GER). We aimed also to evaluate the association of GER with childhood DA, relationship of GER severity with childhood asthma control test (C-ACT), FEV(1), peak expiratory flow (PEF) variability, and ISSP. Finally, we tried to evaluate esomeprazole treatment effect on C-ACT and FEV(1) in children with DA. Methods. Spirometry, C-ACT, upper gastrointestinal endoscopy, and ISSP measurement were done for children with DA compared to healthy controls. Results. ISSP was high in DA with higher levels in the group having associated GER. In the latter group, ISSP and C-ACT improved significantly after esomeprazole treatment while FEV(1) and PEF variability did not improve. Reflux severity was positively correlated with ISSP and negatively correlated with FEV(1). Conclusions. GER was found in 49% of our patients with childhood DA. Very high ISSP levels in children with DA may be used as a marker for presence of GERD. Esomeprazole therapy improved asthma symptoms but did not improve lung function.

Bronchial hyperreactivity in non-atopic children with asthma and reflux: effect of anti-reflux treatment

INTRODUCTION

The prevalence of bronchial hyperreactivity (BHR) or the effect of anti-reflux treatment on BHR in children with asthma and gastroesophageal reflux disease (GERD) is not known.

METHODS

Thirty non-atopic children with persistent asthma were studied. Extended esophageal pH monitoring was used to diagnose GERD and methacholine challenge test (MCT) was used as a marker of BHR and performed before and 2 years after anti-GERD treatment.

RESULTS

Of the 21 patients positive for GERD (group A), 15 had positive MCT suggesting BHR. Of the 9 patients negative for GERD (group B), 5 had positive MCT. On repeat testing 2 years later, 11/15 group A patients and 3/5 group B patients tested negative for BHR. Group A patients were receiving fewer asthma medications and experienced fewer exacerbations than Group B patients.

CONCLUSIONS

BHR is prevalent in children with asthma and GERD and improves with anti-GERD treatment.

Magnesium and calcium in exhaled breath condensate of children with asthma and gastroesophageal reflux disease

BACKGROUND

Magnesium and calcium physiologic functions are closely related. Magnesium is primarily an intracellular cation, the action of which also involves maintenance of cellular ionic balance, while influencing calcium homeostasis by blocking calcium channels. The aim of this study was to compare the concentrations of magnesium and calcium in exhaled breath condensate (EBC) of children with asthma and gastroesophageal reflux disease (GERD).

SUBJECTS AND METHODS

EBC was collected from 66 children aged 7-14 years (23 children with acute asthma, 17 children with GERD, and 26 healthy children). Determination of magnesium and calcium concentrations was preceded by optimization and validation for low concentrations.

RESULTS

No difference was recorded for either magnesium or calcium concentration between study groups. However, the magnesium to calcium ratio was statistically significantly lower in both GERD and asthma children as compared with control group.

CONCLUSION

Study results showed the magnesium to calcium ratio to be a statistically significantly better indicator of certain pathologic changes than absolute concentration of either ion.

Body mass index-percentile and diagnostic accuracy of childhood asthma

OBJECTIVE

To determine whether high BMI-percentile is associated with misdiagnosis of asthma among children referred to an asthma specialist.

METHODS

We queried the electronic records of children 8 to 18 years of age seen by a Nemours pediatric pulmonologist. All visits during a 6-year period with the chief complaint of asthma, or an asthma-like symptom such as wheeze, cough, or dyspnea, were included. We collected spirometry, blood counts, and immunoglobulin E (IgE) if available. We determined whether the child had referring physician-diagnosed asthma, specialist-diagnosed asthma, or both. Specialist-diagnosed asthmatics who met additional objective "gold-standard" criterion were labeled strict-criterion asthma.

RESULTS

Prevalence of high BMI-percentile was extremely common in all defined asthma groups, even those meeting strict criteria for diagnosis. Referring physician-diagnosed asthmatics did not have higher rates of obesity, and referring physician-diagnosed asthmatics had objective indicators of asthma that were the same as asthmatics diagnosed by a specialist. There was good diagnostic correlation between referring physicians and asthma specialists that was not affected by BMI. Among specialist-diagnosed asthmatics, increased BMI-percentile associated with significantly reduced forced expiratory volume in 1 second (FEV(1)), forced expiratory flow during the middle half of the forced vital capacity (FEF(25 - 75)), and FEV(1)/forced vital capacity (FVC); and significantly increased total blood leukocytes, neutrophils, and platelets compared to leans. For all 2,258 referrals, the estimated odds ratio of receiving a specialist-diagnosis of asthma increased by 0.4% with each increasing BMI percentile.

CONCLUSIONS

Referring physicians do not appear to erroneously diagnose children with asthma due to overweight status. Our data confirm that overweight status is extremely high in children with true asthma and likely increases the risk for true asthma. Although these data cannot discern causality, high BMI-percentile is associated with greater airflow obstruction and elevated markers of systemic inflammation that could contribute to underlying mechanisms of asthma.

The effect of surgically created gastroesophageal reflux on intrapleural pressures in dogs

The causal relationship between gastroesophageal reflux (GER) and respiratory disorders is not well understood. Previous experimental studies that investigated this relationship were performed in anesthetized animals and used artificial acidification of esophagus for simulation of GER. In this study, we investigated the impact of GER on intrapleural pressures (IPP) in conscious, unanesthetized dogs. After the induction of appropriate anesthesia, 5 purpose-bred mongrel dogs underwent reflux-creating surgery (partial cardiomyectomy). The presence of GER was confirmed by determining the reflux index (RI) and the duration of longest reflux episode (DLRE) after 24-h intraesophageal pH-metry. IP was monitored before and after cardiomyectomy using a subcutaneously placed telemetric implant with its pressure-sensor catheter tip inserted into the pleural space. Partial cardiomyectomy resulted in a significant increase in RI from a preoperative mean value of 0.38 +/- 0.21 to 7.52 +/- 2.56%, and DLRE from 1.22 +/- 1.12 to 36.80 +/- 12.71 min, as recorded by the proximal sensor of the pH probe. A similar trend was observed at the distal sensor. After cardiomyectomy, the negative inspiratory IPP significantly increased from 17.2 +/- 7.9 to 28.4 +/- 9.7 mm Hg. A similar effect was observed in the negative expiratory IPP. The negative inspiratory IPP had a significant correlation with both RI (R = 0.932) and DLRE (R = 0.899). Cardiomyectomy causes GER, the severity of which correlates with negative inspiratory IPP in a dog model. The suggested model allows for the investigation of the pathologic association of GER with respiratory disorders in conscious animals.

Effect of antireflux treatment on asthma exacerbations in nonatopic children

OBJECTIVE

To evaluate the asthma outcome of treatment with ranitidine or esomeprazole plus metoclopramide in older children with moderate-persistent asthma and gastroesophageal reflux disease (GERD).

PATIENTS AND METHODS

The study patients included 44 patients with asthma and GERD who had received 1 year of treatment with a proton pump inhibitor/prokinetic combination and had shown significant clinical improvement in asthma symptoms and no exacerbations for more than 3 months. For further treatment, 30 of the 44 patients continued treatment with esomeprazole/metoclopramide (group A), and 14 switched to ranitidine (group B). Nine patients with GERD and asthma who had previously undergone fundoplication were used as control individuals (group C). All patients were followed up closely for exacerbation of asthma symptoms and treated according to a standardized protocol.

RESULTS

During the 6-month follow-up, group B patients experienced significantly more exacerbations per patient (2.2) than did those in group A (0.33) or group C (0.77) (P < 0.05).

CONCLUSIONS

Fundoplication or continued treatment with esomeprazole and metoclopramide is associated with significantly fewer exacerbations of asthma symptoms in children with moderate-persistent asthma and concomitant GERD in comparison with treatment with ranitidine.