Longitudinal microbiome changes in children exposed to proton pump inhibitors.

INTRODUCTION: Proton pump inhibitor (PPI) use has been associated with an increased risk of gastrointestinal and upper respiratory infections in children. There are limited longitudinal data on the effect of PPI in children. The goal of this prospective observational study was to compare the stool and oropharyngeal microbiome of children before and after starting PPIs. METHODS: We prospectively recruited participants from a gastroenterology clinic. Consented pariticpants provided stool samples and oropharyngeal swabs at baseline and after eight weeks of PPI therapy. Microbiome changes were measured by analyzing 16S sequencing from both body sites at both timepoints. RESULTS: Thirty-four participants completed the study and provided samples both at baseline and after eight weeks on PPI therapy. Of those, 24 participants had sufficient sequencing from both stool and oropharyngeal samples at both time points. There were no differences between the pre- vs post-PPI samples using beta-diversity metrics in either the oropharynx or stool. There were, however, significant changes in specific taxa. There was an enrichment of Streptococcus in the stool in after PPI-use and a reduction in the relative abundance of Bifidobacterium, Peptostreptococcus and Turicibacter (p-values < 0.01). Furthermore, there was an increase in the relative abundance of oropharyngeal bacteria in the stool after PPI therapy. This enrichment of oropharyngeal bacteria in the stool was most prominent in younger participants. DISCUSSION: Further investigation is needed to determine the clinical and microbial factors that predispose or protect against microbiome changes due to PPI-use, and why young children are more susceptible to this PPI effect.

The utility of balloon-based and standard impedance technology to diagnose esophageal mucosal diseases in children.

BACKGROUND: Standard impedance catheters and balloon-based mucosal impedance catheters (BBMI) have been used to assess mucosal integrity and diagnose mucosal diseases. The goal of this study was to determine the age-related technical issues associated with mucosal balloon inflation, validate the BBMI measurement against a standard impedance probe, and compare software-generated diagnoses to histologic diagnoses. METHODS: We prospectively recruited patients undergoing endoscopy, during which patients underwent standard mucosal impedance catheters and BBMI measurements. Measurements were compared to each other, to the histologic diagnoses, and to the number of eosinophils per high power field. We then compared the patients' diagnosis to that assigned by the BBMI software. KEY RESULTS: Sixty-two patients (mean age: 62 ± 62 months) were recruited, including non-GERD (N = 40), GERD (N = 15), and EoE (N = 7) patients. There were significant differences between the impedance values measured by the two technologies at each esophageal height (p < 0.003). There were significant correlations between the mean impedance values taken by the two catheters in the distal (r2 = 0.272, p = 0.04), mid (r2 = 0.371, p < 0.001), and proximal (r2 = 0.259, p = 0.05) esophagus. There were significant differences in BBMI impedance values across diagnoses in the mid and proximal esophagus (p = 0.024 and 0.025, respectively). While not statistically significant (p = 0.061-0.073), the standard catheter showed similar trends by diagnosis. Using the BBMI diagnostic prediction software, 33%-72% of patients were misclassified. CONCLUSION AND INFERENCES: While there was significant variability in impedance values between technologies within patients, regional measurements were consistent across catheters. Automated analyses lacked the sensitivity to diagnose inflammatory disorders.

A Prospective Study of Parental Experience with Thickening Feeds for Children with Oropharyngeal Dysphagia and Gastroesophageal Reflux.

Thickening is efficacious and commonly recommended for oropharyngeal dysphagia and gastroesophageal reflux. Little is known about parental experience with this practice. Results of this cross-sectional questionnaire study suggest attitudes are positive, but parents frequently adjust recipes/nipple sizes, which might increase aspiration risk. Clinical follow-up is essential to ensure safe feeding.

Airway Impedance: A Novel Diagnostic Tool to Predict Extraesophageal Airway Inflammation.

OBJECTIVE: To validate a novel biomarker, airway impedance for extraesophageal disease. STUDY DESIGN: We prospectively recruited patients with respiratory symptoms undergoing combined endoscopy and direct laryngoscopy for the evaluation of symptoms. The direct laryngoscopy was performed and videotaped for blinded scoring by 3 otolaryngologists and an impedance catheter was placed onto the posterior larynx to obtain measurements. Following this, an endoscopy was performed and impedance measurements and biopsies were taken at 3 esophageal heights. Impedance values were compared within and between patients. RESULTS: Eighty-eight patients were recruited, of which 73 had complete airway and endoscopic exams. There was no significant correlation between airway impedance values and mean reflux finding scores (r2 = 0.45, P = .07). There was no significant positive correlation between airway impedance and esophageal impedance values (r2 = 0.097-0.138, P > .2). Patients taking proton pump inhibitors had significantly lower mean airway impedance values (706 ± 450 Ω) than patients not taking them (1069 ± 809 Ω, P = .06). Patients who had evidence of aspiration on video fluoroscopic swallow studies had lower airway impedance (871 ± 615 Ω) than patients without aspiration (1247 ± 360 Ω, P = .008). Inhaled steroids did not impact airway impedance levels (P = .7). CONCLUSIONS: Airway impedance may be an important diagnostic tool to diagnose gastroesophageal reflux or aspiration, eliminating the subjectivity of airway appearance alone.