title: Intestinal pH and gastrointestinal transit profiles in cystic fibrosis patients measured by wireless motility capsule.
abstract: OBJECTIVE
  The effect of the cystic fibrosis transmembrane conductance regulator protein (CFTR) defect in pancreatic insufficient (PI) patients with cystic fibrosis (CF) on the gastrointestinal pH profile is poorly defined. Adequate and efficient neutralization of the gastric acidity in the duodenum is important for nutrient absorption and timely release of pancreatic enzyme replacement therapy (PERT). We utilized a wireless motility capsule (WMC) to study intestinal pH profile and gastrointestinal transit profile in CF subjects.
  
  
  METHODS
  WMC studies were done on ten adult CF patients with PI while off acid suppression medication and ten age, gender and BMI matched healthy controls. Mean pH over 1 min increments and area under the pH curve over 5 min increments was calculated for the first hour post gastric emptying. Paired t-test was used to compare means of the pH recordings, transit profiles and analysis of time interval required to reach and maintain pH >5.5 and 6.0.
  
  
  RESULTS
  A statistically significant difference was observed between mean pH values during the first 23 min of small bowel transit (p < 0.05). In CF subjects, there was a significant delay in time interval required to reach and sustain pH 5.5 and pH 6.0 (p < 0.001), which is required for PERT dissolution. Only small bowel transit in CF subjects was noted to be significantly delayed (p = 0.004) without a compensatory increase in whole gut transit time.
  
  
  CONCLUSIONS
  We have demonstrated a significant delay in the small intestinal transit and a deficient buffering capacity required to neutralize gastric acid in the proximal small bowel of patients with CF.
authors.affiliation: Department of Pediatrics, Digestive Diseases and Nutrition Center, Women and Children's Hospital of Buffalo, State University of New York at Buffalo School of Medicine and Biomedical Sciences, 219 Bryant Street, Buffalo, NY 14222, USA. dgelfond@upa.chob.edu
authors.forename: Daniel
authors.initials: D
authors.lastname: Gelfond
authors.forename: Changxing
authors.initials: C
authors.lastname: Ma
authors.forename: Jack
authors.initials: J
authors.lastname: Semler
authors.forename: Drucy
authors.initials: D
authors.lastname: Borowitz
mesh_terms: D000293:Adolescent; D000328:Adult; D053704:Capsule Endoscopy / Q000295:instrumentation*; D003550:Cystic Fibrosis / Q000378:metabolism*; D005260:Female; D005769:Gastrointestinal Motility; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007422:Intestines / Q000737:chemistry*; D008297:Male; D010865:Pilot Projects; D055815:Young Adult