title: Toxic bile acids in gastro-oesophageal reflux disease: influence of gastric acidity.
abstract: BACKGROUND
  Bile acid toxicity has been shown in the gastric, colonic, and hepatic tissues; the effect on oesophageal mucosa is less well known.
  
  
  OBJECTIVE
  To determine the spectrum of bile acids refluxing in patients with gastro-oesophageal reflux disease and its relation to oesophageal pH using a new technique of combined oesophageal aspiration and pH monitoring.
  
  
  METHODS
  Ten asymptomatic subjects and 30 patients with symptoms of gastro-oesophageal reflux disease (minimal mucosal injury, erosive oesophagitis (grade 2 or 3 Savary-Miller), Barrett's oesophagus/stricture; n=10 in each group) underwent 15 hour continuous oesophageal aspiration with simultaneous pH monitoring. Bile acid assay of the oesophageal samples was performed using modified high performance liquid chromatography.
  
  
  RESULTS
  The peak bile acid concentration and DeMeester acid scores were significantly higher in the patients with oesophagitis (median bile acid concentration 124 micromol/l; acid score 20.2) and Barrett's oesophagus/stricture (181 micromol/l; 43. 3) than patients with minimal injury (14 micromol/l; 12.5) or controls (0 micromol/l; 11.1). The predominant bile acids detected were cholic, taurocholic, and glycocholic acids but there was a significantly greater proportion of secondary bile acids, deoxycholic and taurodeoxycholic acids, in patients with erosive oesophagitis and Barrett's oesophagus/stricture. Although bile acid reflux episodes occurred at variable pH, a temporal relation existed between reflux of taurine conjugates and oesophageal acid exposure (r=0.58, p=0.009).
  
  
  CONCLUSIONS
  Toxic secondary bile acid fractions have been detected in patients with extensive mucosal damage. Mixed reflux is more harmful than acid reflux alone with possible toxic synergism existing between the taurine conjugates and acid.
authors: Singleton Hospital, Swansea, UK.
authors: D
authors: D
authors: Nehra
authors: P
authors: P
authors: Howell
authors: C P
authors: CP
authors: Williams
authors: J K
authors: JK
authors: Pye
authors: J
authors: J
authors: Beynon
mesh_terms: D000328:Adult; D000368:Aged; D001471:Barrett Esophagus / Q000209:etiology / Q000378:metabolism; D001647:Bile Acids and Salts / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D004942:Esophagitis, Peptic / Q000378:metabolism; D004947:Esophagus / Q000378:metabolism; D005260:Female; D005745:Gastric Acidity Determination; D005764:Gastroesophageal Reflux / Q000150:complications / Q000378:metabolism*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D008875:Middle Aged
chemical_list: D001647:Bile Acids and Salts