Esophageal impedance/pH monitoring in pediatric patients: preliminary experience with 50 cases

Utility of the Post-Reflux Swallow-Induced Peristaltic Wave Index and Mean Nocturnal Baseline Impedance for the Diagnosis of Gastroesophageal Reflux Disease Phenotypes in Children

(1) Objectives: Assessment of novel impedance parameters such as the post-reflux swallow-induced peristaltic wave (PSPW) index and mean nocturnal baseline impedance (MNBI) have been proposed to enhance the accuracy of gastroesophageal reflux disease (GERD) diagnosis. We aimed to evaluate the clinical value of MNBI and the PSPW index in discerning different phenotypes of GERD in children. (2) Methods: We conducted a prospective, observational study that included 49 children aged 5-18 years, referred for MII-pH monitoring due to negative endoscopy and persisting gastroesophageal reflux symptoms despite acid-suppressant treatment. The PSPW index and MNBI were assessed along with conventional metrics. (3) Results: Using a receiver operating characteristic (ROC) curve analysis, MNBI (AUC 0.864) and the PSPW index (AUC 0.83) had very good performance in differentiating between non-erosive reflux disease (NERD) and functional phenotypes. The PSPW index (AUC 0.87) discriminated better between functional heartburn (FH) and reflux hypersensitivity (RH) compared to the MNBI (AUC 0.712). A PSPW cut-off value of 65% provided a sensitivity of 76.9% and a specificity of 90% in distinguishing FH and RH. The PSPW index (AUC 0.87) proved to have better performance than the MNBI (AUC 0.802) in differentiating between FH and non-FH patients. MNBI diagnosed FH with a sensitivity of 84% and a specificity of 80.6% at a cut-off value of 2563 Ω. (4) Conclusions: The PSPW index and MNBI are useful to distinguish between GERD phenotypes in pediatric patients.

Infant gastroesophageal reflux disease management consensus

AIM

Infant gastroesophageal reflux is mostly benign; however, when associated with complications like failure to thrive, it may be indicative of gastroesophageal reflux disease. There are currently several unmet needs pertaining to the management of infant gastroesophageal reflux (disease). Reflux in infants is mostly composed of breast milk or formula, so this population is significantly different to older children and adults. The objective of this Delphi consensus was to establish recommendations based on published literature and the experience of clinical experts in paediatric gastroenterology in the context of infant gastroesophageal reflux (disease).

METHODS

The Delphi methodology was used to obtain a consensus on 18 statements relating to clinical aspects of infant gastroesophageal reflux (disease).

RESULTS

The expert panel comprising paediatric gastroenterology clinical specialists reached a consensus for all statements by means of an online, anonymised voting system.

CONCLUSION

It was highlighted that there is generally low awareness of or adherence to guidelines in clinical practice and that acid suppression therapy should not be indicated for non-acid reflux, which constitutes a significant proportion of total gastroesophageal reflux episodes among infants. Furthermore, it was emphasised that there is an unmet medical need for therapy for some symptomatic infants with non-acid reflux disease.

The Real Relevance of Nonacid Reflux in Pediatric Patients

Gastroesophageal reflux (GER) is one of the most common presenting complaints to pediatric gastroenterologists, and a wide variety of symptoms in children are potentially attributable to typical or atypical GER. While reflux diagnosis and treatment paradigms classically have focused on targeting acid, there is a growing recognition of the prevalence and significance of nonacid GER in both children and adults. This review explores the role of nonacid reflux in pediatric patients, including definitions, associations with symptoms, pathophysiologic mechanisms, and treatment implications.

Preschool Wheezing and Gastro-Esophageal Reflux: --Causal or Casual Coincidence? Update from Literature

Gastroesophageal reflux (GER) and wheeze are two common conditions in children. GER has been advocated as a causative factor for explaining recurrent to persistent respiratory symptoms at any age. This association very often means that many children with cough, wheezing, or recurrent respiratory infections receive empirical anti-reflux medications. The causal relationship is still largely discussed. Compared to the large number of studies in infants and adolescents, literature on the relationship between GER and wheeze in preschool children is scarce and inconclusive. The aim of the present narrative review was to summarize what is known so far, and what the literature has proposed in the last 20 years, on the relationship between preschool wheezing and GER. In preschool children with respiratory symptoms there is a high rate of positivity of reflux testing, for this reason pH-MII testing and endoscopy are recommended. Flexible bronchoscopy may be useful to exclude anatomical abnormalities as the cause of wheezing in infancy and preschool years. Several biomarkers, as well as empirical anti-reflux therapy, have been proposed for the diagnosis of GER-related airway diseases, but the conclusions of these studies are controversial or even conflicting. There is a great need for future clinical trials to confirm or rule out the association.

The utility of multichannel intraluminal impedance-pH testing in tailoring the management of paediatric gastro-oesophageal reflux disease

AIM

To determine whether combined multichannel intraluminal impedance and pH (MII-pH) testing led to a change in management of children with gastro-oesophageal reflux disease (GORD).

METHODS

Retrospective chart review was done in all patients who underwent MII-pH testing for GORD symptoms at Sydney Children's Hospital between 2008 and 2016. Changes to anti-reflux medications and referral for anti-reflux surgery were evaluated.

RESULTS

There were 365 patients, 260 (71.2%) of whom were on acid-suppressing therapy. The median age was 4.1 ± 4.8 years, 205 patients (56%) were males, 83 (22.7%) were infants (<1 year of age) and 145 (39.7%%) had comorbid conditions. We found 72.1% had abnormal MII-pH results, of which 17.5% had abnormal acid reflux, 8.2% had abnormal number of retrograde bolus movements and 46.3% had hypersensitive oesophagus (positive symptom association only). Infants were significantly more likely to have abnormal MII-pH results compared to older children (P = .04). Results of MII-pH testing led to medication changes in 44.7% and referral for anti-reflux surgery in 6.8% of patients.

CONCLUSION

Combined multichannel intraluminal impedance and pH testing is clinically useful in the management of children with symptoms of GORD and over half the patients had changes to their medical treatment or referral for anti-reflux surgery based on the results of MII-pH testing. It resulted in a treatment change in an additional 32% of patients over traditional pH-metry.

Acid and bolus exposure in pediatric reflux disease according to the presence and severity of esophageal mucosal lesions

PURPOSE

The relationship between reflux index (RI) and bolus exposure parameters in multichannel intraluminal impedance (MII) has not been examined sufficiently among children. The significance of acid and bolus exposure in evaluating pediatric reflux disease (RD) was explored by focusing on mucosal lesions.

METHODS

We conducted MII-pH on 28 patients (median age 8 years) with suspected RD. We assessed relationships between RI and bolus exposure indices, and also compared acid and bolus exposures across patients grouped by endoscopic esophageal mucosal lesions.

RESULTS

RI correlated significantly with distal acid reflux events (r = 0.60), acid bolus exposure time (BET) (0.55), and bolus clearance time (BCT) (0.48). Significant differences were observed among the control, non-erosive RD (NERD), and erosive RD (ERD) groups in all acid and several bolus exposure indices (distal and proximal frequencies, and BCT), while no significant difference was apparent between NERD and ERD. Acid exposure tended to be more severe in high-grade than in low-grade ERD, while no similar tendency was found in any bolus parameters other than BCT.

CONCLUSIONS

MII-pH showed great potential for investigating the pathophysiology of pediatric RD, with RI revealing different correlations with variable bolus exposure indices. However, no specific parameters allowing precise discrimination between RDs or mucosal severities were identified.

Differentiation of esophageal pH-impedance characteristics classified by the mucosal integrity marker in human neonates

BACKGROUND

In adults, distal baseline impedance (BI) is a determinant of esophageal mucosal integrity with values <900 Ω indicating inflammation. Relationships between acid gastroesophageal reflux (GER) and BI in neonates are unclear.

METHODS

NICU infants (N = 198, 30.4 ± 0.3 weeks gestation) were evaluated at 43 ± 0.4 weeks postmenstrual age using 24-h pH-impedance. Ten randomly selected 1-min windows during rest from the distal impedance channel (Z6) were averaged. Chi-square, t-tests, and ANOVA were used to compare pH-impedance and symptom characteristics by BI severity (BI < 900 Ω, BI 900-2000 Ω, BI > 2000 Ω). Regression analysis was used to identify potential contributing factors of BI.

RESULTS

In BI < 900 Ω: (1) pH-impedance characteristics were increased (acid reflux event frequency, duration, and severity, all P < 0.05 vs. BI > 2000 Ω), and (2) positive symptom correlations were noted with bolus (73%) and acid events (55%). Significant predictors of BI included chronological age, acid reflux index, and BPD diagnosis (all P < 0.05).

CONCLUSIONS

Low BI is associated with prolonged acid exposure, delayed clearance, and greater aerodigestive symptom prevalence, likely associated with inflammation and or increased mucosal permeability. BI > 2000 Ω likely involves little or no inflammation because acid exposure is minimal. Combination of SAP, pH-impedance metrics, and BI along with the clarification of dysmotility mechanisms provides the rationale for personalized anti-reflux therapies as needed.

Combined multichannel intraluminal impedance and pH monitoring is helpful in managing children with suspected gastro-oesophageal reflux disease

BACKGROUND

Gastro-oesophageal reflux is very common in the paediatric age group. There is no single and reliable test to distinguish between physiologic and pathological gastro-oesophageal reflux, and this lack of clear distinction between disease and normal can have a negative impact on the management of children.

AIMS

To evaluate the usefulness of 24-h oesophageal pH-impedance study in infants and children with suspected gastro-oesophageal reflux disease.

METHODS

Patients were classified by age groups (A-C) and reflux-related symptoms (typical and atypical). All underwent pH-impedance study. If the latter suggested an abnormal reflux, patients received therapy in accordance with NASPGHAN/ESPGHAN recommendations, while those with normal study had an additional diagnostic work-up. The efficacy of therapy was evaluated with a specific standardized questionnaire for different ages.

RESULTS

The study was abnormal in 203/428 patients (47%) while normal in 225/428 (53%). Of those with abnormal study, 109 exhibited typical symptoms (54%), and 94 atypical (46%). The great majority of the patients with abnormal study were responsive to medical anti-reflux therapy.

CONCLUSIONS

We confirm the utility of prolonged oesophageal pH-impedance study in detecting gastro-oesophageal reflux disease in children and in guiding therapy. Performing oesophageal pH-impedance monitoring in children with suspected gastro-oesophageal reflux disease is helpful to establish the diagnosis and avoid unnecessary therapy.

Pediatric Gastroesophageal Reflux Clinical Practice Guidelines: Joint Recommendations of the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition and the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition

This document serves as an update of the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHAN) and the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) 2009 clinical guidelines for the diagnosis and management of gastroesophageal reflux disease (GERD) in infants and children and is intended to be applied in daily practice and as a basis for clinical trials. Eight clinical questions addressing diagnostic, therapeutic and prognostic topics were formulated. A systematic literature search was performed from October 1, 2008 (if the question was addressed by 2009 guidelines) or from inception to June 1, 2015 using Embase, MEDLINE, the Cochrane Database of Systematic Reviews and the Cochrane Central Register of Controlled Clinical Trials. The approach of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) was applied to define and prioritize outcomes. For therapeutic questions, the quality of evidence was also assessed using GRADE. Grading the quality of evidence for other questions was performed according to the Quality Assessment of Studies of Diagnostic Accuracy (QUADAS) and Quality in Prognostic Studies (QUIPS) tools. During a 3-day consensus meeting, all recommendations were discussed and finalized. In cases where no randomized controlled trials (RCT; therapeutic questions) or diagnostic accuracy studies were available to support the recommendations, expert opinion was used. The group members voted on each recommendation, using the nominal voting technique. With this approach, recommendations regarding evaluation and management of infants and children with GERD to standardize and improve quality of care were formulated. Additionally, 2 algorithms were developed, 1 for infants <12 months of age and the other for older infants and children.

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.

Role of non-acid gastro-esophageal reflux in children with respiratory symptoms

OBJECTIVES

Respiratory symptoms are a possible atypical clinical picture of gastro-esophageal reflux disease (GERD). However, a significant number of patients with GERD-related respiratory symptoms do not report improvement despite aggressive acid-suppressive therapy. Some of these refractory cases may be due to the recently appreciated entity of non-acid or weakly acidic reflux. The aim of our study is to assess the pH-impedance features of GER inducing airway symptoms, compared with GER inducing typical gastro-intestinal (GI) symptoms.

METHODS

We prospectively enrolled infants and children with GERD-related respiratory symptoms from January 2015 to December 2015. Age- and sex-matched patients with GERD-related GI symptoms were enrolled as comparison group. The overall number, the acidity pattern, and the height of reflux episodes were compared between the two groups.

RESULTS

Forty patients (M/F: 20/20; mean age: 58.3 months) were enrolled in the study group and 40 in the comparison group. The mean acid exposure index was 7.9% within the study group and 15.9% within the comparison group (p:0.026). Children with respiratory symptoms versus children with GI symptoms had a mean of 40.8 acid reflux episodes versus 62.4 (p:0.001), a mean of 2.2 weakly acid reflux episodes versus 20.1 (p:0.002), and a mean of 22.1 weakly alkaline reflux episodes versus 10.2 (P < 0.001). Separate analysis of both infants and children was performed.

CONCLUSIONS

The main finding of this prospective, controlled study is that children >1 year with GERD-related respiratory symptoms showed a significantly higher number of weakly alkaline refluxes than children with GERD-related GI symptoms. This supports the hypothesis that respiratory symptoms are less related to acidity than GI symptoms. Pediatr Pulmonol. 2017;52:669-674. © 2016 Wiley Periodicals, Inc.

COMBINED 24-HOURS ESOPHAGEAL PH MONITORING AND MULTICHANNEL INTRALUMINAL IMPEDANCE FOR COMPARISON OF GASTROESOPHAGEAL REFLUX IN CHILDREN WITH TYPICAL VERSUS ATYPICAL SYMPTOMS OF GASTROESOPHAGEAL REFLUX DISEASE

ABSTRACT Background - Gastroesophageal reflux disease is the most common esophageal disorder in pediatrics. Objective - The aim of this study was to compare reflux parameters of typical and atypical symptoms of gastroesophageal reflux disease using 24-hour esophageal pH monitoring and multichannel intraluminal impedance in pediatric population. Methods - In this prospective study, 43 patients aged less than 18 year with suspected gastroesophageal reflux disease were enrolled. The patients were divided into two groups based on the main presenting symptoms (typical versus atypical). Twenty four-hour pH monitoring and multichannel intraluminal impedance were performed in all the patients for comparing these two group regarding association of symptoms and reflux. Number of refluxes, pH related reflux, total reflux time, reflux more than 5 minutes, longest time of the reflux, lowest pH at reflux, reflux index were recorded and compared. Data comparison was done using SPSS. Results - The mean age of the patients was 5.7±3.4 years and 65.1% were male. Out of 43 patients 24 cases had typical symptoms and 19 had atypical symptoms. The mean reflux events detected by multichannel intraluminal impedance was more than mean reflux events detected by pH monitoring (308.4±115.8 vs 69.7±66.6) with P value of 0.037, which is statistically significant. The mean symptom index and symptom association probability were 35.01% ± 20.78% and 86.42% ± 25.79%, respectively in multichannel intraluminal impedance versus 12.73% ± 12.48% and 45.16% ± 42.29% in pH monitoring (P value <0.001). Number of acid reflux was 46.26±47.16 and 30.9±22.09 for atypical and typical symptoms respectively. The mean symptom index was 18.12% ± 13.101% and 8.30% ± 10.301% in atypical and typical symptoms respectively (P=0.034). Bolus clearance was longer in atypical symptoms compared typical symptoms(P<0.05). Conclusion - Symptom index was significantly higher in atypical symptoms compared to typical symptoms. Higher number of acid reflux was found in children with atypical symptoms of reflux. Longer duration of bolus clearance was found in group with atypical symptoms of reflux.

The feasibility and efficacy of multi-channel intraluminal impedance monitoring in children

INTRODUCTION

The diagnosis of gastro-oesophageal reflux is currently based on clinical presentation and oesophageal pH monitoring. In recent years, the use of multi-channel intraluminal impedance (MII) monitoring has gained increasing attention in the adult population. However, its use in the paediatric population is still in the developing stage with only limited number of publications. This study aims to review our early experience of MII application in children.

METHODS

A retrospective study of all patients who underwent MII monitoring between 2011 and 2014 at a tertiary referral centre was performed. Patients' medical records were reviewed with demographic data extracted. Number of reflux episodes and other MII parameters were analysed.

RESULTS

In total, 34 patients were identified during the study period, with 20 males and 14 females. Indication for study included previous aspiration pneumonia (n = 13), persistent reflux or vomiting symptom (n = 10) and as part of routine assessment before gastrostomy (n = 11). At the time of study the average age was 69 months (range 9-216 months). 28 patients showed significant gastro-oesophageal reflux. On average patient has 36.1 acidic and 22.3 non-acidic reflux episodes during the 24 h monitoring period. Non-acidic reflux accounts for 38.1 % of the overall reflux episodes. The sensitivity of MII monitoring to detect reflux was higher compared to conventional pH study (73 vs 50 %, p = 0.1).

CONCLUSION

MII monitoring is safe and feasible in children. Non-acid reflux should not be underestimated in paediatric population. MII appears to be more sensitive than conventional pH monitoring in our study, but its true significance is yet to be confirmed by larger study in the future.

Association between gastroesophageal reflux and pathologic apneas in infants: a systematic review

BACKGROUND

In infants, apneas can be centrally mediated, obstructive or both and have been proposed to be gastroesophageal reflux (GER) induced. Evidence for this possible association has never been systematically reviewed.

PURPOSE

To perform a systematic review using PubMed, EMBASE and Cochrane databases to determine whether an association between GER and apnea in infants exists. Studies with n ≥ 10 infants, aged <12 months, were included. GER had to be studied by pH-metry or pH-impedancemetry. GER episodes were defined as pH <4 for ≥ 5 s and/or a drop of >50% of baseline in impedance signal in distal channels. An apneic event was defined as a cessation of breathing for >20 s, or ≥ 10 s with hypoxemia or bradycardia. An epoch of ≤ 2 min was used to define temporal relation between GER and apnea. Methodological quality of studies was assessed with Newcastle Ottawa Scale (NOS). Of 1959 abstracts found, 6 articles met the inclusion criteria. All studies had poor methodological quality. A total of 289 infants were included. The temporal association of GER followed by apnea was assessed in all studies, with epochs varying from 10 s to 2 min. One study found an increase of apneic events after GER, the remaining 5 studies did not find an association. Two studies assessed apnea followed by GER as well, but did not find sufficient evidence for association. This systematic review showed insufficient evidence for an association between GER and apneas in infants. High quality studies using uniform inclusion criteria, definitions according to accepted guidelines, and patient relevant outcome measures are needed.

Esophageal atresia: gastroesophageal functional follow-up in 5-15 year old children

PURPOSE

Esophageal atresia (EA) is one of the most frequent congenital alimentary tract anomalies with a considerable morbidity throughout childhood. This study evaluates the gastroesophageal problems in 5-15 year old children with EA and aims to identify factors predisposing to esophagitis in EA.

MATERIAL AND METHODS

Fifty-nine patients primarily operated at Odense University Hospital, Denmark, during 1993-2005 were included in this follow-up study. The patients underwent the following examinations: Interview, upper endoscopy, endoscopic ultrasonography, high-resolution esophageal manometry (HREM), and pH- and multichannel intraluminal impedance (MII) measurements. Twenty-five patients with suspected gastro-esophageal reflux disease (GERD) underwent the same investigations and served as controls.

RESULTS

Median age was 10.2 years (7.1-13.3). Thirty-three (55.9%) presented with GERD symptoms, 41 (69.5%) with dysphagia, and 33 (55.9%) with respiratory symptoms. Twenty-nine (49.2%) had endoscopic esophagitis, and 26 (44.1%) histological esophagitis. Median reflux index (RI) was 8.3 (4.8-14.9). In 32 (55.2%) RI was above 7. Ten percent had eosinophilic inflammation. HREM showed dysmotility in the esophagus in all EA patients, 83.3% had no propagating swallows. No predictive factors predisposing the development of endoscopic esophagitis were identified.

CONCLUSIONS

Gastroesophageal problems in children born with EA are common. Routine follow-up with endoscopy and pH-metry in EA patients is warranted.

Gastroesophageal reflux in patients treated for congenital diaphragmatic hernia: short- and long-term evaluation with multichannel intraluminal impedance

PURPOSE

The incidence of GER, related symptoms and complications in patients treated for congenital diaphragmatic hernia (CDH) are poorly defined. The aim was to evaluate incidence and development of GER in children treated for CDH in a short- and long-term follow-up period, identifying potential risk factors of morbidity.

METHODS

Thirty-six patients were evaluated with pH-MII at a median age of 6 months (T1) and re-evaluated with pH-MII and endoscopy at a median age of 5 years (T2).

RESULTS

The incidence of reflux was 83 % in T1 and 61 % in T2; the incidence of symptoms was 62 % in T1 and 38 % in T2. In both groups the reflux was mainly non-acidic. Patch, intrathoracic stomach and esophageal dysmotility were risk factors for GER.

CONCLUSIONS

The incidence of GER and symptoms decrease over the time but it was higher than in the literature, probably because it is mainly non-acidic and evaluable only with MII. The esophageal dysmotility was found to be the main risk factor. An high incidence of reflux and esophagitis was found also in asymptomatic patients, and so a close follow-up is recommended in all patients even if it is asymptomatic.

Weakly acidic gastroesophageal refluxes are frequently triggers in young children with chronic cough

OBJECTIVE

To evaluate whether the proportion of acid and weakly acidic refluxes preceding cough bursts could be different in infants, preschool- and school-aged children with chronic, unexplained cough.

PATIENTS AND METHODS

One hundred six children with unexplained chronic cough, not receiving acid suppressive therapy, underwent impedance-pH monitoring. They were divided into Group A: <2 years (21 pts), Group B: ≥2 to ≤6 years (41 pts), and Group C: >6 years (44 pts). Reflux was defined as acid (pH <4), weakly acidic (WA; pH 4-7), and weakly alkaline (pH >7).Cough episodes were considered temporally associated with gastroesophageal reflux (GER) when occurring within 2 min after a GER episode.

RESULTS

Impedance-pH detected 55.50 (39.00-76.00) reflux episodes/patient with an acid-to-WA reflux event ratio of 3.31 (1.55-8.33). This parameter was significantly lower in Group A (1.33 [0.41-3.40]) than in Group B (3.06 [2.00-6.50]; P < 0.05] and Group C (5.09 [2.34-12.43; P < 0.001]). No cough episode was preceded by weakly alkaline refluxes in any patient. During impedance-pH recording, 93 patients (87.7%) had at least one cough episode that had been preceded by impedance refluxes in 83 patients. In this latter group (83 pts), the median number of cough episodes was 12.0 (5.0-25.5), of which 48.15% (30.15-71.43%) were preceded by refluxes; GER-preceded cough episodes were similar in the three groups. The majority of children had cough episodes preceded by acid refluxes in the total population (78.3%), in Group B (80.5%) and in Group C (93.7%), but not in Group A (40.0%; P < 0.001).

CONCLUSIONS

In addition to acid, also a significant proportion of WA GER may precede cough episodes in young children with persistent cough, possibly explaining the inconstant effects of anti-acid treatment on respiratory symptoms.

[Esophageal atresia]

Most of the children operated for esophageal atresia will survive the neonatal period. However, medium-term and late complications are frequent in this population. Gastroesophageal reflux disease is observed in 26 to 75% of the cases and can be responsible for peptic esophagitis, anastomotic stenosis, and Barrett esophagus, which is a risk factor for adenocarcinoma of the esophagus. Dysphagia is frequently observed, sometimes several years after the surgery, affecting up to 45% of children at the age of 5 years. Growth retardation is present in nearly one-third of children at the age of 5 years. Ear, nose, and throat and respiratory complications are also very frequent but tend to improve with time. Tracheomalacia is found in 75% of these children at birth, sometimes responsible for severe complications (malaise, bradycardia). Respiratory symptoms are dominated by chronic cough, wheezing, and infections reported in 29% of the children by the age of 5 years. Restrictive, obstructive syndromes and bronchial hyperactivity can be observed, but usually remain moderate. All these complications can influence the patient's quality of life, which is moderately impaired compared to healthy controls. The high frequency of late sequelae in esophageal atresia justifies regular and multidisciplinary follow-up through adulthood.

Evaluation of esophageal motility and reflux in children treated for congenital diaphragmatic hernia with the use of combined multichannel intraluminal impedance and pH monitoring

BACKGROUND

Gastroesophageal reflux (GER) is frequently observed in children treated for congenital diaphragmatic hernia (CDH) at birth, as well as esophageal dysmotility, that has been hypothesized to be caused by innervatory anomalies. The aim of this study is to evaluate GER and dysmotility in young patients with CDH using pH-multichannel intraluminal impedance.

METHODS

Thirty children (17 boys and 13 girls) who underwent repair for CDH between 2002 and 2007 with a median age of 5.2 years (range, 3-10 years) were included in the study. All patients were operated on with a subcostal laparotomy incision and had a left-sided diaphragmatic defect. The defect repair required an artificial patch (Goretex, Gore Medical, Flagstaff, AZ) in 8 patients (27%) because of its size. We described impedance reflux parameters and some specific motility parameters studied on 10 standardized swallows.

RESULTS

The incidence of GER was 86%. Reflux was mainly nonacidic, postprandial, and short-term and reached only the distal esophagus. Esophageal dysmotility was observed only in the distal esophagus.

CONCLUSIONS

With the use of pH-multichannel intraluminal impedance, both GER and esophageal motility in patients with congenital malformations can be analyzed. In patients with CDH, impaired motility seems to involve only the distal esophagus. In this group, the specific pattern of reflux is probably caused by the involvement of gastroesophageal junction, without significant intrinsic innervation abnormalities as observed in patients with esophageal atresia.

Diagnosis of gastroesophageal reflux disease in infants

Gastroesophageal reflux is commonly encountered in the infant population. Most children will outgrow their reflux but some develop pervasive disease and require medical or surgical treatment. Many tools exist for use in the workup of pediatric gastroesophageal reflux disease; however, the most effective method of diagnosis is not clear. Delineating which patients will benefit from more definitive therapy is a remarkable challenge in this group, often borrowing tools and principles from the adult patient population. Therefore, we reviewed the available literature to critically evaluate the merits and limitations of the current diagnostic modalities available for the evaluation of infantile gastroesophageal reflux.

Gastroesophageal reflux in young children treated for esophageal atresia: evaluation with pH-multichannel intraluminal impedance

OBJECTIVES

Gastroesophageal reflux (GER) and dismotility occur frequently after repair of esophageal atresia (EA). GER-associated complications can manifest either early or later; then precocious diagnosis and treatment are essential. The aim of the study was to evaluate characteristics of GER and esophageal clearance in children treated for EA with distal tracheoesophageal fistula, using pH-multichannel intraluminal impedance (pH-MII).

PATIENTS AND METHODS

Twenty-two children (ages 3-40 months) treated for EA at birth, and 20 normal children of similar age with suspected GER disease were included in the study. Impedance parameters were analyzed according to age and symptoms.

RESULTS

Reflux events were mainly nonacidic. About bolus exposure index, mean acid clearing time (MACT), and mean bolus clearing time (MBCT), a significant difference was found between 2 groups: the median MACT and MBCT were longer, with values of 281 and 39 seconds, respectively, in the EA group and 110 and 15 seconds in the control group (P < 0.0005).

CONCLUSIONS

Our data show that in young patients the majority of refluxes are not acid. This implies that the incidence of GER may be underestimated if pH-metry is used. The pH-MII is an ideal test in children because it studies both GER with its characteristics and motility pattern. The quality of reflux does not seem to influence the onset of symptoms that are related to an impaired esophageal clearance. Hence, this technique could be useful to study patients treated for EA, avoiding the onset of complications.

Evaluation of esophageal motility and reflux in children treated for esophageal atresia with the use of combined multichannel intraluminal impedance and pH monitoring

BACKGROUND

Gastroesophageal reflux (GER) and dysmotility are frequent in patients treated for esophageal atresia (EA). This aim of this study is to evaluate GER and dysmotility in young EA patients using pH-multichannel intraluminal impedance (pH-MII).

METHODS

Fifteen patients with a mean age of 7.5 years (group 1) have been studied and compared with 15 children without congenital malformation, submitted to pH-MII for suspected GER (group 2). These latter patients serve as a control group of healthy subjects. The following impedance reflux and motility parameters have been studied on 10 standardized swallows: number of reflux episodes, mean acid clearing time, median bolus clearing time, bolus presence time, total bolus transit time, segmental transit time, and total propagation velocity.

RESULTS

In the group of EA patients, mean acid clearing time and median bolus clearing time were pathological. In the control group, all reflux parameters were normal. Patients with EA had significantly longer median bolus presence time at each measuring site, median total bolus transit time, and median segmental transit time and slower total propagation velocity (P < .001).

CONCLUSIONS

pH-multichannel intraluminal impedance evaluates both GER and motility patterns. Our report studies impedance parameters of esophageal motility in healthy children and in EA patients using only pH-MII.

Acid and weakly acid gastroesophageal refluxes and type of respiratory symptoms in children

OBJECTIVES

To evaluate the association between the frequency of acid reflux (AR) and weakly acid reflux (WAR) and specific respiratory symptoms (RS) in childhood.

STUDY DESIGN

We retrospectively reviewed medical records of children with difficult-to-treat RS, not under acid suppressive therapy, and with a positive multiple intraluminal esophageal impedance (pH/MII) monitoring. To discriminate children with prevalent AR and WAR events, a ROC curve was designed and the distribution of the different RS in children with prevalent AR or WAR events was analyzed.

RESULTS

A higher number of AR over WAR events was detected (p < 0.0001) but the WAR-to-AR events ratio progressively decreased with the age of the subjects (p < 0.01). Similar total number of reflux events was found in the three age group and in children with a more prevalent WAR or AR. The most prevalent RS, equally distributed among the three age groups, were persistent and/or nocturnal cough, wheezy bronchitis/asthma, and recurrent lower respiratory tract infections (RLRTI). Apnoea was most frequent in infants (p = 0.036). A higher frequency of RLRTI, but not of nocturnal cough or wheezy bronchitis/asthma, was shown in WAR as compared with AR patients (p = 0.040), and specifically those in the school-aged group (p = 0.013). Age and WAR were respectively identified as independent predictors of apnoea and RLRTI (p < 0.05).

CONCLUSION

WAR events are common in children with gastroesophageal reflux and difficult-to-treat RS and often associated with RLRTI. These findings support the role of pH/MII monitoring in the evaluation of these patients and may explain the disappointing clinical results often observed with anti-acid treatments.

Evaluation of esophageal motility using multichannel intraluminal impedance in healthy children and children with gastroesophageal reflux

OBJECTIVE

Multichannel intraluminal impedance (MII) directly evaluates esophageal bolus transport. There is a good correlation between MII and manometry in healthy adults, but there are no reports concerning children.The aim of the present study was to determine normal values of esophageal motility using only impedance measurements in healthy children and in a pediatric population with gastroesophageal reflux (GER).

PATIENTS AND METHODS

We described in the present study 60 children submitted to pH-MII for 24 hours for suspected GER. Patients were divided into 2 different groups on the basis of their pH-MII report. Group 1 patients showed acid GER, whereas group 2 patients had negative pH-MII analysis for GER despite symptoms. We described impedance reflux and motility parameters on 10 standardized swallows: number of reflux, mean acid clearing time, median bolus clearing time, bolus presence time, total bolus transit time, segmental transit time, and total propagation velocity.

RESULTS

In group 1, the median mean acid clearing time was 151 seconds, whereas the median mean bolus clearing time was 25 seconds. In group 2 patients, all of the reflux parameters were normal. In group 1 the median bolus presence time at each measuring site, the median total bolus transit time, and the median segmental transit time were significantly greater and total propagation velocity lower than values reported in group 2 (P < 0.001), if compared with those described for adult patients.

CONCLUSIONS

The pH-MII is an ideal test in children because it studies GER with its characteristics and motility pattern. Our report summarizes for the first time impedance motility parameters in healthy children.

Esophageal impedance in children: symptom-based results

OBJECTIVE

To correlate multiple intraluminal esophageal impedance recording with pH-monitoring with symptoms.

STUDY DESIGN

Symptoms occurring within a 2-minute window of a reflux were considered to be associated with reflux. Analyses were performed in 1- to 6-, 6- to 12-, and >12-months-old patients for crying, pain, cough, and vomiting.

RESULTS

A total of 70 of 225 tracings were discarded. Of 2172 symptoms, 1136 (52%) were reflux-associated (45% acid reflux [AR], 51% weakly AR, 3% alkaline reflux). The strongest reflux-symptom association was found for vomiting. Cough-reflux association was higher in infants than in older children. In older patients, symptom-reflux association was more with AR. Symptoms were associated with proximal reflux in 70% of patients. The symptom index and symptom association probability (SAP) were positive (>50% for symptom index and >95% for SAP) for all refluxes in 83% and 46% of patients and for AR in 49% and 47% of patients, respectively. In 1- to 6-month-old infants, symptom index and SAP were higher for weakly AR than for AR. For crying, SAP was independent of AR or weakly AR. For cough, SAP was positive in one-third of patients, predominantly with AR in 6- to 12-month-old infants and with weakly AR in the other infants.

CONCLUSION

Multiple intraluminal esophageal impedance recording with pH-monitoring doubles the probability of documenting an association between symptoms and reflux compared with pH monitoring. In young infants, symptoms are more frequently associated with weakly AR than with AR.

Gastroesophageal reflux disease and eosinophilic esophagitis in infants and children. A study of esophageal pH, multiple intraluminal impedance and endoscopic ultrasound

OBJECTIVE

Eosinophilic esophagitis (EE) and gastroesophageal reflux disease (GERD) in childhood share aspects of symptomatology. In order to characterize EE and GERD in infants and children with symptoms of GERD we performed a prospective investigation including prolonged esophageal pH measurement, multiple intraluminal impedance (MII) and esophageal wall estimation by endoscopic ultrasound (EUS).

MATERIAL AND METHODS

Infants and children (0-15 years) with typical symptoms of GERD persisting after a 14-days proton pump inhibitor trial were included in a prospective study protocol. Upper endoscopy and EUS of the esophageal wall were performed followed by combined esophageal MII and pH measurement for 24 h.

RESULTS

A total of 78 infants and children were investigated: EE patients (n = 6), GERD patients (n = 28) and a group of infants and children with normal investigations (n = 44). The GERD group did not show a significantly higher number of non-acid reflux episodes (p = 0.9) than the patients with normal investigations. In all patients gastroesophageal reflux regularly extended into the proximal esophagus. EUS in four EE patients suggested an increased thickness of the mucosal layers both in the distal and in the proximal part of the esophagus.

CONCLUSIONS

Esophageal MII indicated that neutral non-acid reflux episodes do not occur frequently in pediatric GERD or in EE. MII and pH-metry indicated that the majority of reflux episodes both in patients and controls pass into the proximal esophagus. EUS measurements suggested in EE patients a thickened mucosa both in the proximal and the distal part of the esophagus as compared to children with GERD and disease controls.

Can acid (pH) refluxes predict multichannel intraluminal impedance refluxes? A correlation study

BACKGROUND AND AIM

The present study aims to explore if and when acid (pH) refluxes can predict refluxes detected by multichannel intraluminal impedance (MII) studies. This correlation may indicate whether pH probe-only and MII-pH studies are interchangeable.

METHODS

Prospective observational cross sectional study of symptomatic children (below 18 years) who had MII-pH studies done for gastroesophageal reflux. Clinical data were extracted from patient records. Non-parametric tests, Pearson's rho and receiver operating characteristic (ROC) curves were used for data analysis.

RESULTS

A total of 153 children were included in the study and 62% were on acid suppression. Indices for acid and MII refluxes correlated with each other only in those without acid suppression. This correlation was lost in children on acid suppression. There was no statistically significant difference in acid or MII reflux indices in children with or without acid suppression. Like acid reflux, indices for MII refluxes had good correlation with each other irrespective of acid suppression. Liquid and mixed MII refluxes showed excellent correlation with respective types of proximally migrating refluxes. The values for MII reflux indices derived from our patient population were in broad agreement with available pediatric and adult data.

CONCLUSIONS

A pH probe-only study in patients without acid suppression may reflect both acid and volume (MII) reflux activities adequately and can substitute for MII-pH study. The observed excellent correlation between acid and MII refluxes with proximal migration may justify using pH probe-only studies for extra esophageal symptoms in patients without acid suppression.

Characteristics of gastroesophageal reflux and potential risk of gastric content aspiration in children with cystic fibrosis

OBJECTIVES

Increased gastroesophageal reflux (GER) is common in children with cystic fibrosis (CF). We studied the occurrence of acid, weakly acidic (WA), and weakly alkaline (WALK) reflux in children with CF and evaluated a possible surrogate marker for risk of gastric content aspiration.

PATIENTS AND METHODS

Twenty-four children with CF underwent impedance-pH monitoring for detection of acid (pH < 4), WA (pH 4-7), and WALK-GER (pH > or = 7). In 11 children, cough was objectively recorded with esophageal manometry and the symptom association probability was calculated to determine the reflux-cough relation. Presence of bile acids (BA) was measured in the saliva of 65 patients with CF and 23 healthy children, respectively.

RESULTS

Sixteen of the 24 children had increased GER (esophageal acid exposure). The majority of reflux events were acidic in nature. WA reflux was less common and WALK reflux was rare. The sequence reflux-cough was found in 8 of the 11 children and 1 of 11 children had a positive symptom association probability for reflux-cough. The sequence cough-reflux was found in only 3 of the 11 children. Only a small fraction of the total esophageal acid and volume exposure was secondary to cough. Twenty-three of the 65 children with CF had BA in saliva compared with none of the healthy controls.

CONCLUSIONS

Although WA-GER is uncommon, acid GER is prevalent in children with CF. It is a primary phenomenon and is not secondary to cough. One third of the children with CF have BA in saliva, which may indicate an increased risk for aspiration. However, the impact of salivary BA and potential aspiration on CF pulmonary disease needs further investigation.

Esophageal impedance and esophagitis in children: any correlation?

AIM

: The aim of this study was to correlate the data obtained with multiple intraluminal esophageal impedance and pH (MII-pH) recordings in infants and children referred for suspected gastroesophageal reflux disease with esophageal histology.

MATERIALS AND METHODS

: In a prospective study, results of esophageal biopsies and MII-pH recording obtained in 45 children (mean age +/- SD: 69 +/- 55 months) were analyzed. Regarding the MII-pH data, an automatic (Autoscan Bioview Analysis Software, version 5.3.4, Sandhill Scientific Inc, Highlands Ranch, CO) and a manual reading were performed; an automatic pH analysis (meal included) was also performed.

RESULTS

: Acidic, weakly acidic, and alkaline reflux episodes accounted, respectively, for 48.7%, 49.5%, and 1.8% of the total number of reflux episodes detected by MII-pH. Esophagitis was present in 25 (56%) children. Concordance between classic pH-study analysis (alone) and esophageal histology was found in 19 of 45 (42%) children. According to the MII-pH analysis, the mean and median value of the pH were significantly higher in the group with esophagitis than in the group with normal esophageal histology. A longer clearance time was found in the group with esophagitis than in subjects with normal histology. Gas reflux episodes represented 21% of the total reflux episodes and were comparable in both groups.

CONCLUSIONS

: Multiple intraluminal esophageal impedance and pH analysis does not provide a distinct parameter to predict esophageal mucosal injury in children. In our population, MII-pH shows comparable acidic, weakly acidic, alkaline, and gas reflux in children with and without esophagitis. Further research is needed to analyze clearance parameters.

Role of the multichannel intraluminal impedance technique in infants and children

Recently, multichannel intraluminal impedance (MII) was added to the repertoire of tests available to study esophageal (patho)physiology in children. MII has since been used in 2 major areas. First, it has been used as a diagnostic test for gastroesophageal reflux disease (GERD). The main advantage over traditional pH monitoring is its ability to detect both acid and nonacid gastroesophageal reflux (GER) and to discern between liquid and gas GER.Although feasible with multiple pH sensors, the MII technique routinely detects the proximal extent of a GER episode. When a pH sensor is added to the MII-catheter, important information about the acidity of a GER event can be gathered.The second area in which the role of MII has been investigated is that of esophageal function testing. Manometry classically reveals information about esophageal pressure patterns and sphincter function, but does not inform us about bolus flow. MII not only detects the presence of esophageal flow but also adds information on the direction of flow, duration of bolus presence, completeness of bolus clearance, and composition of a bolus.The combination of MII with manometry enables determination of the relationship between esophageal pressures and flow and, therefore, enhances evaluation of esophageal function in terms of assessment of mechanisms of esophageal volume clearance. In addition, this technique will improve our understanding of (patho)physiological mechanisms in pediatric GERD and other esophageal motility disorders.

Esophageal impedance-pH monitoring

Classical techniques like endoscopy and esophageal pH-metry are routinely used to study patients with symptoms related to gastroesophageal reflux disease (GERD). Although these techniques have been useful over the years both for diagnosis and therapeutic guidance, there are still many patients with typical or atypical GERD symptoms with normal endoscopy and pH-metry that do not respond adequately to antisecretory therapy. Ambulatory esophageal impedance-pH monitoring is a new technique that can be used to evaluate all types of gastroesophageal reflux, achieving higher rates of sensitivity and specificity than standard techniques. This review describes esophageal impedance-pH monitoring, summarizing the current literature on validation studies and clinical application.

Gastro-oesophageal reflux disease: oesophageal impedance versus pH monitoring

Gastro-oesophageal reflux occurs frequently during the first months of life. Infants receive frequent milk feeds, and because milk is a potent buffer of gastric acidity, oesophageal impedance should detect more reflux than pH recording. Indeed, impedance has the advantage over pH monitoring of being independent of pH, and as a consequence, of being better adapted to measure reflux during postprandial periods when reflux is buffered and to detect symptoms associated with non-acid or weakly acid reflux episodes. Numerous episodes are detected by one of these techniques (pH monitoring or impedance) in children. Most studies using the impedance technique consider very small numbers of patients, and there are few reports linking data from diagnostic impedance procedures to clinical outcome in symptomatic patients. Data suggesting that impedance does offer a clear-cut benefit in paediatric clinical practice are missing. The high cost of the material and the investment in time necessary for interpretation of the recording, remains a handicap. It is mandatory, despite ethical difficulties, to obtain normal ranges for intraluminal impedance monitoring.

CONCLUSION

As pH monitoring is part of impedance technology, it is likely that the latter will replace pH monitoring despite the current lack of scientific evidence demonstrating a relation between symptoms, oesophageal damage or response to reflux treatment and impedance-pH results.