title: Kinetics of primary bile acids in patients after proctocolectomy and ileal pouch-anal anastomosis.
abstract: BACKGROUND
  The high incidence of cholesterol gallstones in patients after proctocolectomy with ileal pouch-anal anastomosis (IPAA) may be due to an increased loss of bile acids. We aimed to evaluate the kinetics of the primary bile acids cholic acid (CA) and chenodeoxycholic acid (CDCA) in these patients.
  
  
  METHODS
  Pool sizes, synthesis rates, and fractional turnover rates of CA and CDCA were determined by combined capillary gas chromatography/isotope ratio mass spectrometry in serum samples after administration of [¹³C]CA and [¹³C]CDCA in 6 patients and 9 healthy volunteers.
  
  
  RESULTS
  In patients with IPAA, pool sizes of CA and CDCA were 11.5 (8.2-23.8) and 12.1 (6.7-20.1) µmol/kg, respectively, and were significantly lower than in healthy controls [36.0 (24-47) and 29.0 (21-42) µmol/kg, respectively; p < 0.05, each]. Fractional turnover rates of CA [1.19 (1.06-1.82) vs. 0.31 (0.13-0.54) per day] and CDCA [1.01 (0.50-1.63) vs. 0.23 (0.09-0.36) per day] were increased fourfold in patients with IPAA (p < 0.05, each). Synthesis rates of CDCA [10.2 (5.2-32.9) vs. 6.6 (2.7-10.5) µmol/kg per day, p = 0.05] and CA [15.1 (9.3-39.4) vs. 11.5 (3.1-20.5) µmol/kg per day, n.s.] tended to be higher in patients with IPAA than in controls.
  
  
  CONCLUSIONS
  The reduced pool size of primary bile acids may contribute to the high incidence of cholesterol gallstones in patients after proctocolectomy and IPAA.
authors.affiliation: Department of Gastroenterology, University of Heidelberg, Heidelberg, Germany.
authors.forename: Daniel Nils
authors.initials: DN
authors.lastname: Gotthardt
authors.forename: Peter
authors.initials: P
authors.lastname: Sauer
authors.forename: Anja
authors.initials: A
authors.lastname: Schaible
authors.forename: Josef
authors.initials: J
authors.lastname: Stern
authors.forename: Adolf
authors.initials: A
authors.lastname: Stiehl
authors.forename: Ulrich
authors.initials: U
authors.lastname: Beuers
mesh_terms: D000328:Adult; D001003:Anal Canal / Q000601:surgery*; D000714:Anastomosis, Surgical; D016022:Case-Control Studies; D002635:Chenodeoxycholic Acid / Q000493:pharmacokinetics*; D019826:Cholic Acid / Q000493:pharmacokinetics*; D039021:Colonic Pouches; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016737:Proctocolectomy, Restorative
chemical_list: D002635:Chenodeoxycholic Acid; D019826:Cholic Acid