BSPGHAN Motility Working Group position statement: paediatric multichannel intraluminal pH impedance monitoring-indications, methods and interpretation

Analysis of multichannel intraluminal impedance and pH monitoring values in children with cerebral palsy: A comparative multicenter study

OBJECTIVES

To compare the features of multichannel intraluminal impedance and pH monitoring (MII-pH) tracings in children with cerebral palsy (CP) and children without CP.

METHODS

Multicenter, retrospective, analytical study. We examined tracings of children aged 1 to 15 years old, evaluated from May 2017 to January 2024. Population included two groups: Group 1 consisted of children with CP, while control group comprised children without CP who had extra-digestive symptoms suggestive of gastroesophageal reflux disease (GERD) but normal MII-pH results. Quantitative data were analyzed using analysis of variance and t tests. Qualitative data were analyzed using contingency tables and chi-square tests.

RESULTS

We studied 245 children. CP group included 110 children with a mean age of 5.71 years (standard deviation [SD] ± 4.24), while control group included 135 children with a mean age of 5.73 years (SD ± 3.39). The CP group had fewer reflux episodes (p = 0.0015), slower mean acid clearance time (p = 0.04), lower mean baseline impedance and mean nocturnal baseline impedance (p = 1.82e-07 and p = 7.50e-07).

CONCLUSION

Children with CP have fewer reflux episodes and longer acid clearance times compared with children without CP. Prospective studies including esophagogastroduodenoscopy findings are needed to establish MII-pH reference values in children with CP.

Gastroesophageal reflux during postpyloric versus gastric tube feeding in preterm infants with bronchopulmonary dysplasia

BACKGROUND

Whether postpyloric feeding reduces gastroesophageal reflux (GER) in very preterm infants with bronchopulmonary dysplasia (BPD) is uncertain.

METHODS

Prospective observational study comparing GER profiles measured using 24-h esophageal pH-impedance monitoring in infants with BPD receiving clinically prescribed postpyloric (n = 21) or gastric (n = 24) tube feeding.

RESULTS

Participants (median gestational age 25.0 weeks, IQR 24.1-26.9) underwent testing at a median postmenstrual age of 46.6 weeks (IQR 42.7-52.4). The number of GER episodes recorded by impedance varied widely (median 27, range 1-195). Postpyloric versus gastric feeding was associated with fewer GER episodes (median, IQR: 16, 5-41 vs. 40, 19-60; p = 0.07) and less exposure of the proximal esophagus to reflux (median duration, IQR: 0.1 min, 0.005-0.6 vs. 0.77 min, 0.16-1.8; p = 0.045), but a higher proportion of acidic (pH < 4) GER episodes (median, IQR: 91%, 70-100 vs. 31%, 16-54; p < 0.001).

CONCLUSION

Postpyloric feeding may reduce total GER burden but increase the relative proportion of acidic GER in infants with BPD.

Comparison between Conventional and Simple Measuring Methods of Mean Nocturnal Baseline Impedance in Pediatric Gastroesophageal Reflux Disease

(1) Background: Multichannel intraluminal impedance-pH (MII-pH) monitoring is commonly used to diagnose gastroesophageal reflux disease (GERD). The mean nocturnal baseline impedance (MNBI) is an important parameter, reflecting the esophageal mucosal integrity and improvement in GERD. This study aims to evaluate the correlation between conventionally measured MNBI and a recently described simple MNBI measurement method in diagnosing pediatric GERD. (2) Methods: This prospective observational study enrolled 64 children aged one month to 18 years who underwent 24 h MII-pH monitoring. Conventional MNBI was measured during stable 10 min intervals at night, while the simple MNBI method averaged impedance throughout the nocturnal supine period. (3) Results: Strong correlations were found between conventional and simple MNBI values across all impedance channels in both infants (r > 0.85) and older children (r > 0.9). Conventional and simple MNBIs in the most distal channel (Z6) effectively differentiated non-erosive reflux disease (NERD) from other phenotypes, with AUCs of 0.864 and 0.860, respectively. The simple MNBI demonstrated good diagnostic performance with similar sensitivity and specificity to the conventional MNBI. (4) Conclusions: Including MNBI measurements into routine MII-pH monitoring may enhance GERD diagnosis and reduce the need for more invasive procedures.

A new formula proposal for placing pH-impedance catheters in pediatric patients

INTRODUCTION

Esophageal pH-impedance monitoring is a tool for diagnosing gastroesophageal reflux in children. The position of the pH catheter is essential for a reliable reading and the current formulas for calculating catheter insertion length are not completely accurate. The aim of the present study was to develop a new formula for adequate insertion of the pH catheter.

MATERIAL AND METHODS

A cross-sectional study was conducted on children that underwent pH-impedance monitoring and later radiographic control, to calculate the correct catheter insertion length. The documented variables were age, sex, weight, height, naris to tragus distance, tragus to sternal notch distance, sternal notch to xiphoid process distance, and initial insertion length determined by the Strobel and height interval formulas. A multivariate regression analysis was carried out to predict the final insertion length. Regression ANOVA and Pearson's adjusted R-squared tests were performed.

RESULTS

Forty-five pH-impedance studies were carried out, 53% of which were in males. The age and weight variables were not normally distributed. In the initial regression model, the variables that did not significantly correlate with the final insertion length were: sex (P 0.124), length determined by the Strobel or height interval formulas (P 0.078), naris to tragus distance (P 0.905), and tragus to sternal notch distance (P 0.404). The final equation: 5.6 + (height in cm * 0.12) + (sternal notch to xiphoid process distance * 0.57) produced an R2 of 0.93 (P 0.000).

CONCLUSIONS

This formula can be considered a valid option for placement of the pH-impedance monitoring catheter in pediatrics.

Executing and facilitating the successful combined multichannel intraluminal impedance and pH monitoring study

Successful multichannel intraluminal impedance and pH monitoring (MII-pHM) studies rely on constant attendants (CAs) or family members (and sometimes the patients themselves) to assist in the execution and facilitation of the MII-pHM study. While "pushing buttons" [corresponding to specific symptoms, body position (upright versus recumbent), and meal start and stop times] on the MII-pHM system recording box is indeed a big part of MII-pHM study execution and facilitation, there are other concerns and duties that are equally as important. This paper outlines some of the important duties of the study facilitator (or patient) during a MII-pHM study. When provided with the proper training, study facilitators invigilating the MII-pHM study will be better able to contribute to the data collection process and ultimately to produce data that when analyzed will lead to better interpretations, clinical recommendations, and good clinical outcomes. When executed properly, MII-pHM studies have the potential to assess diurnal exposure of the esophageal mucosa to gastric/duodenal contents, provide insight regarding the proximal extent of gastroesophageal reflux (GER), provide a measurement of the mean esophageal pH, and assess mucosal integrity and temporal relationship between GER and the symptoms of interest. While several groups have offered recommendations for proper execution of the MII-pHM study, to our knowledge, there have not been publications wherein recommendations were compiled to form a single source document.

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.

The Utility of Novel pH-Impedance Monitoring Parameters (PSPW Index and MNBI) in Pediatric Gastroesophageal Reflux Disease Phenotypes-A Systematic Review

Background/Objectives: Researchers have proposed two novel impedance-pH parameters, mean nocturnal baseline impedance (MNBI) and the post-reflux swallow-induced peristaltic wave (PSPW) index, to enhance the diagnosis of gastroesophageal reflux disease (GERD) and enable better predictions of the effectiveness of anti-reflux therapies. This systematic review aims to synthesize the available evidence on the utility of the PSPW index and MNBI as diagnostic tools for pediatric GERD. Methods: A systematic search of studies reporting PSPW index and MNBI values in patients with GERD was performed in PubMed, Embase, Clarivate, Scopus, Cochrane and Google Scholar databases from their beginning until April 2024. The following terms were used: GERD, children, pediatric, PSPW and MNBI. Results: Eight studies were included, describing 479 patients ranging from 2 months to 17 years old over an 8-year period in 12 pediatric centers. Four studies demonstrated that children with pathological acid exposure have a significantly lower MNBI, with a good discriminatory ability to diagnose GERD. The PSPW index showed lower values in patients with reflux hypersensitivity (RH) compared to those with functional heartburn (FH). Conclusions: Patients with pathological acid exposure tend to exhibit lower MNBI and PSPW index values compared to those with normal acid exposure. MNBI and the PSPW index show promise as diagnostic tools in distinguishing between different GERD phenotypes. Further research is needed to establish standardized diagnostic criteria and optimize the clinical applicability in GERD diagnosis and management.

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

BACKGROUND

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSION

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

Prevalence of Non-erosive Esophageal Phenotypes in Children: A European Multicenter Study

BACKGROUND/AIMS

Since available data on pediatric non-erosive esophageal phenotypes (NEEPs) are scant, we investigated their prevalence and the phenotype-dependent treatment response in these children.

METHODS

Over a 5-year period, children with negative upper endoscopy, who underwent esophageal pH-impedance (off-therapy) for persisting symptoms not responsive to proton pump inhibitor (PPI)-treatment, were recruited. Based on the results of acid reflux index (RI) and symptom association probability (SAP), patients were categorized into: (1) abnormal RI (non-erosive reflux disease [NERD]), (2) normal RI and abnormal SAP (reflux hypersensitivity [RH]), (3) normal RI and normal SAP (functional heartburn [FH]), and (4) normal RI and not-reliable SAP (normal-RI-not otherwise-specified [normal-RI-NOS]). For each subgroup, treatment response was evaluated.

RESULTS

Out of 2333 children who underwent esophageal pH-impedance, 68 cases, including 18 NERD, 14 RH, 26 FH, and 10 normal-RI-NOS were identified as fulfilling the inclusion criteria and were analyzed. Considering symptoms before endoscopy, chest pain was more reported in NERD than in other cases (6/18 vs 5/50, P = 0.031). At long-term follow-up of 23 patients (8 NERD, 8 FH, 2 RH, and 5 normal-RI-NOS): 17 were on PPIs and 2 combined alginate, 1 (FH) was on benzodiazepine + anticholinergic, 1 (normal-RI-NOS) on citalopram, and 3 had no therapy. A complete symptom-resolution was observed in 5/8 NERD, in 2/8 FH, and in 2/5 normal-RI-NOS.

CONCLUSIONS

FH may be the most common pediatric NEEP. At long-term follow-up, there was a trend toward a more frequent complete symptom resolution with PPI-therapy in NERD patients while other groups did not benefit from extended acid-suppressive-treatment.

Prediction of refractory gastroesophageal reflux disease in young children

BACKGROUND

Many children respond to medical treatment for gastroesophageal reflux disease (GERD). However, some may require invasive intervention for refractory disease. Due to the lack of prognostic tools in children, this study aimed to develop a predictive model for refractory GERD.

METHODS

A retrospective review was performed in children with symptoms of GERD at a university hospital. Refractory GERD was defined as an unresponsive disease after optimal treatment with medication for >8 weeks. The predictive model was constructed based on clinical features and 24-h multichannel intraluminal impedance-pH (MII-pH) monitoring results.

RESULTS

A total of 205 children were included with a median (IQR) age of 0.6 (0.3, 2.0) years. Over half of the patients (59.5%) had motor disabilities. Forty-four children (21.5%) were diagnosed with refractory GERD and subsequently underwent fundoplication. Multivariable analysis suggested that the refractory disease was associated with motor disabilities (OR: 5.35; 95% CI: 2.06-13.91), recurrent aspiration pneumonia (OR: 2.78; 95% CI: 1.24-6.26), prematurity with an onset of GERD at a post-conceptual age <40 weeks (OR: 6.76; 95% CI: 1.96-23.33), and abnormal total reflux episodes according to age (OR: 2.78; 95% CI: 1.24-6.19), but not the acid exposure time or symptom association analysis. The predictive model for refractory GERD based on associated factors revealed an area under the ROC curve of 76.8% (95% CI: 69.2%-84.3%) with a sensitivity of 77.3% and a specificity of 64% when applying a cutoff score of ≥2.5.

CONCLUSIONS

The predictive model, using clinical features and MII-pH, may be an additional tool to predict refractory GERD in young children.

Low Mean Nocturnal Baseline Impedance is Associated With a Pathological Acid Exposure Time in Children

BACKGROUND

The baseline impedance (BI) and the mean nocturnal baseline impedance (MNBI) serve as markers of mucosal integrity in patients with pathologic acid exposure time (AET). This work aims to investigate the association between the BI and MNBI with the AET in children.

METHODOLOGY

A retrospective study was performed in children ≤18 years old with suspicion of gastroesophageal reflux disease who underwent both endoscopy and pH-impedance monitoring (pH-MII). Esophagitis was graded according to the Los Angeles classification. The pathological AET was determined depending on the age (≥5% in patients >1 year and ≥10% in those ages ≤1 year). For the BI, 60 s measurements were taken every 4 h, and for the MNBI, 3 10 min measurements were taken between 1.00 and 3:00 am; then, they were averaged. The means of BI and MNBI were compared with each other, with the AET, and other variables.

RESULTS

Sixty-eight patients were included, 25% of patients presented pathological AET. The mean of the MNBI was higher than BI in channels 6 (2195 vs 1997 Ω, P = 0.011) and 5 (2393 vs 2228 Ω, P = 0.013). BI and MNBI at channel 6 were lower in patients with pathological AET than in those with normal AET (1573 vs 2138 Ω, P = 0.007) and (1592 vs 2396 Ω, P = 0.004), respectively.

CONCLUSIONS

Children with pathological AET had lower impedance values than those with normal AET. BI and MNBI measurements should be part of the routine MII-pH assessment in children.

Belching in children: Prevalence and association with gastroesophageal reflux disease

BACKGROUND

Excessive belching is frequently reported in adult patients with gastro-oesophageal reflux disease (GORD) and dyspepsia. Although postprandial gastric belching (GB) is considered a physiological mechanism for gastric venting, supra-gastric belching (SGB) is considered a distinct behavioural disorder. We aimed to define the prevalence of different types of belching and its association with reflux disease in paediatric patients.

METHODS

We retrospectively analysed reflux monitoring studies from 287 patients (median age: 7.0 years; interquartile range 3.0-11.3 years) with a suspicion of GORD. Based on oesophageal acid exposure time (AET) patients were divided in 3 groups: (a) physiological AET, (b) borderline AET and (c) pathological AET. MII-pH studies were manually edited and reflux disease parameters were measured together with quantification of GB and SGB.

KEY RESULTS

Two hundred one children (70.0%) had physiological AET (median: 0.8; interquartile range 0.3-1.6), 52 (18.1%) had borderline AET (median: 4.2; interquartile range 3.4-5.3) and 34 (11.9%) had pathologic AET (median: 10.7; interquartile range 9.1-14.2). Gastric belching was observed in all studies. Gastric belching related reflux was more frequently observed in patients with borderline and pathological AET (p < 0.001). This was more common in older children. SGB were observed in only 7 (2.4%) children (age range: 8-17years) in our population and all patients had Physiological AET. Only 3 (1%) patients had pathological number of SGB (>13/24 h).

CONCLUSIONS AND INFERENCES

Gastric belching related reflux is observed in children with increased AET. SGB is very rare in the paediatric population.

Oesophageal pH-Impedance for the Diagnosis of Gastro-Oesophageal Reflux Disease: Validation of General Population Reference Values in Children with Chronic Neurological Impairments

Diagnosis of gastro-oesophageal reflux disease (GORD) in children with chronic neurological impairment (NI) remains a clinical challenge. The study aimed to validate the relevance of the reference values used to assess gastro-oesophageal reflux (GOR) in children with NI and to determine the optimal cut-off level of the pH-impedance parameter with the best predictive value for outcomes associated with endoscopic assessments of the oesophagus. Sixty-seven children (32 male, 35 female; age: interquartile range, 5 years 6 months-14 years 10 months; median, 11 years 3 months) with NI were prospectively recruited for the study. The exclusion criteria were previous fundoplication and lack of consent for the study. All patients underwent evaluations for GOR disease, including pH-impedance and gastroscopy. Based on endoscopy, oesophagitis was diagnosed in 22/67 children (32.8%); 9/67 (13.4%) were classified as having Hetzel-Dent grade III or IV. GOR was present in 18/67 children (26.9%), as determined by pH-impedance. Patients with endoscopic lesions had a significantly higher number of total reflux (p = 0.0404) and acidic episodes (p = 0.0219). The total number of reflux episodes, with a cut-off level of 44 episodes, was the pH-impedance parameter most strongly predictive of the presence of lesions in gastroscopy (specificity: 50%, sensitivity: 73%). These findings suggest that endoscopic lesions may be present in children with chronic NI with a low number of GOR episodes, as recorded by pH-impedance. The use of standardised reference norms determined for the general population may underestimate GOR episodes in this group of patients.

Understanding gastrointestinal motility studies in pediatrics

Motility of the gut is affected by the nervous system, the endocrine system, smooth muscle cells, interstitial cells of Cajal, secretory mucosal cells, the immune system, and gut flora. Abnormal gastrointestinal motility can generate nonspecific symptom complaints that are refractory to standard treatment approaches. It is important to exclude anatomical obstruction or other causes for patients' symptoms prior to proceeding with motility evaluation. Motility studies that help to evaluate children with suspected motility problems include combined multichannel intraluminal impedance (MII) and pH recording, esophageal manometry, gastric emptying scinitigraphy, antroduodenal manometry, colonic manometry, and anorectal manometry. Many pediatric gastrointestinal motility evaluations should be completed in a pediatric motility center where specialized training is completed by physicians in this field. Indications for pediatric gastrointestinal motility studies and how the procedures are performed are addressed in this paper.

Detection of reflux-symptom association in children with esophageal atresia by video-pH-impedance study

BACKGROUND

Children with esophageal atresia (EA) have risk of gastroesophageal reflux disease (GERD), suggesting reflux monitoring for prompt management.

AIM

To evaluate GERD in children with EA and specific symptom association from combined Video with Multichannel Intraluminal Impedance and pH (MII-pH) study.

METHODS

Children diagnosed with EA with suspected GERD and followed up at King Chulalongkorn Memorial Hospital between January 2000 and December 2018 were prospectively studied. All underwent esophagogastroduodenoscopy with esophageal biopsy and Video MII-pH study on the same day. Symptoms of GERD which included both esophageal and extra-esophageal symptom were recorded from video monitoring and abnormal reflux from MII-pH study based on the statement from the European Paediatric Impedance Group. Prevalence of GERD was also reported by using histopathology as a gold standard. Endoscopic appearance was recorded using Los Angeles Classification and esophagitis severity was graded using Esohisto criteria.

RESULTS

Fifteen children were recruited with age of 3.1 (2.2, 9.8) years (40%, male) and the common type was C (93.3%). The symptoms recorded were cough (75.2%), vomiting (15.2%), irritability or unexplained crying (7.6%) and dysphagia (1.9%) with the symptom-reflux association of 45.7%, 89%, 71% and 0%, respectively. There were abnormal endoscopic appearance in 52.9%, esophagitis in 64.7% and high reflux score in 47.1%. Video MII-pH study has high diagnostic value with the sensitivity, specificity and accuracy of 72.7%, 100% and 82.4%, respectively.

CONCLUSION

Prevalence of GERD in children with EA was high. Video MII-pH study to detect GERD in children with EA had high diagnostic value with the trend of specific symptom association.

Paroxysmal head drops with ataxia-like symptoms presenting as Sandifer syndrome in a 3-year old girl

We present a case of Sandifer syndrome in a 3-year-old girl who initially presented with a history of recurrent paroxysmal head drops associated with ataxia-like symptoms and recurrent falls sustaining a clavicular fracture on one occasion. She was referred to and seen by the paediatric neurologist. Physical examination, electroencephalogram, MRI brain, electromyograph single fibre study and blood tests were all normal. With the history of hiccups and choking-like episodes she was referred to the speech and language therapist (SALT). SALT assessment did not reveal indications of swallowing impairment or possible aspiration. A barium swallow later showed small amount of reflux into the distal oesophagus. This prompted a trial of lansoprazole and she was referral to the gastroenterologists. Endoscopy and oesophageal manometry were essentially normal. However, the pH impedance study revealed severe gastro-oesophageal reflux disease. She continued with lansoprazole and dairy-free diet and her symptoms resolved.