title: Simultaneous prolonged recordings of proximal and distal intraesophageal pH in children with gastroesophageal reflux disease and respiratory symptoms.
abstract: OBJECTIVE
  To characterize both proximal and distal esophageal acid exposure in children with gastroesophageal reflux-related respiratory disease and to investigate the usefulness of dual-channel intraesophageal pH monitoring in these patients.
  
  
  METHODS
  Continuous simultaneous recording of distal and proximal esophageal pH was performed in 40 patients with gastroesophageal reflux disease and respiratory symptoms (wheezing, nocturnal cough, obstructive bronchitis) (age range 3-168 months) (group A), in 20 patients with reflux disease alone (age range 7-156 months) (group B), and in 14 controls (age range 5-108 months) (group C).
  
  
  RESULTS
  (expressed as median +/- SD) 1) The two groups of patients did not differ with regard to distal and proximal esophageal acid exposure (percentage of reflux) during both the total recording period [distal, A: 9.2 +/- 4, B: 10.7 +/- 7 (NS), C: 1.9 +/- 1.0; and proximal, A: 4.8 +/- 3.3, B: 4.0 +/- 3.3 (NS), C: 1.0 +/- 0.7] and during nighttime [distal, A: 8.0 +/- 6.2, B: 10.4 +/- 6.1 (NS), C: 0.9 +/- 0.65; and proximal, A: 3.72 +/- 3, B: 3.6 +/- 3.0 (NS), C: 0.75 +/- 0.45]. 2) The two groups did not differ with regard to the ratio between proximal and distal esophageal acid exposure during both total and nocturnal periods of analysis. 3) No significant correlation was found between distal and proximal esophageal acid exposure during total and nocturnal recording periods. 4) In patients with reflux-related respiratory disease, the respiratory symptomatic index was significantly higher during distal esophageal acid exposure alone (47.0 +/- 28.6%) than during simultaneous reflux at the two esophageal levels (26.9 +/- 27%) (p < 0.05). Furthermore, reflux episodes associated with respiratory symptoms reached lower pH values than those in patients without symptoms at the two recording sites.
  
  
  CONCLUSIONS
  Gastroesophageal reflux into the proximal esophagus does not discriminate between patients with reflux disease alone and those with reflux disease complicated by respiratory symptoms. Symptoms of asthma in reflux patients appear to be elicited more by a reflex mechanism than by aspiration of gastric refluxate into the airways. Intraesophageal acidification seems to be involved in eliciting respiratory symptoms related to reflux disease, and prolonged intraesophageal two-level pH measurement does not seem to be useful in the approach to patients with reflux disease associated with respiratory symptoms.
authors.affiliation: Department of Pediatrics, Faculty of Medicine, University of Naples Federico II, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Cucchiara
authors.forename: F
authors.initials: F
authors.lastname: Santamaria
authors.forename: R
authors.initials: R
authors.lastname: Minella
authors.forename: E
authors.initials: E
authors.lastname: Alfieri
authors.forename: A
authors.initials: A
authors.lastname: Scoppa
authors.forename: F
authors.initials: F
authors.lastname: Calabrese
authors.forename: M T
authors.initials: MT
authors.lastname: Franco
authors.forename: B
authors.initials: B
authors.lastname: Rea
authors.forename: G
authors.initials: G
authors.lastname: Salvia
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004947:Esophagus / Q000378:metabolism*; D005764:Gastroesophageal Reflux / Q000150:complications* / Q000378:metabolism* / Q000503:physiopathology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007223:Infant; D008991:Monitoring, Physiologic; D012140:Respiratory Tract Diseases / Q000209:etiology* / Q000503:physiopathology