title: Measurement of colonic mucosal concentrations of 5-aminosalicylic acid is useful for estimating its therapeutic efficacy in distal ulcerative colitis: comparison of orally administered mesalamine and sulfasalazine.
abstract: OBJECTIVE
  Oral 5-aminosalicylic acid (5-ASA) preparations have been used frequently in the treatment of ulcerative colitis. However, there have been few reports investigating the relationship between colonic mucosal concentrations of 5-ASA and its clinical efficacy when oral sulfasalazine or 5-ASA compounds were administered. The aim of this study is to compare the mucosal concentrations of 5-ASA ensured by sulfasalazine or mesalamine, and to define the clinical significance of the measurement of 5-ASA concentrations in the treatment of distal ulcerative colitis.
  
  
  METHODS
  Biopsies were taken from the rectum and sigmoid colon of the oral sulfasalazine group (n = 13) and the slow-release 5-ASA (mesalamine) group with (n = 5) or without (n = 11) rectal administration of 5-ASA. High-pressure liquid chromatography was used to measure the tissue concentrations of 5-ASA and its metabolites. We compared the 5-ASA concentrations of the sulfasalazine group with the mesalamine group. Furthermore, we analyzed the relationship between tissue 5-ASA concentrations and the Disease Activity Index (DAI).
  
  
  RESULTS
  The concentrations of 5-ASA and acetyl-5-ASA in the sulfasalazine group were higher than those in the group taking oral mesalamine alone (p < 0.01). The concentration of 5-ASA was much higher in the patients who received oral and rectal mesalamine in an enema than in the patients who had oral mesalamine alone. There was a significant inverse correlation between the DAI and concentrations of 5-ASA in the rectum (r = 0.712, p < 0.001).
  
  
  CONCLUSIONS
  We demonstrated that the colonic mucosal concentration of 5-ASA was significantly higher in the sulfasalazine group than in the mesalamine group. Furthermore, the concentrations of mucosal 5-ASA may be a good marker for the estimation of its efficacy in the treatment of ulcerative colitis.
authors.affiliation: Department of Internal Medicine, School of Medicine, Keio University, Tokyo, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Naganuma
authors.forename: Y
authors.initials: Y
authors.lastname: Iwao
authors.forename: H
authors.initials: H
authors.lastname: Ogata
authors.forename: N
authors.initials: N
authors.lastname: Inoue
authors.forename: S
authors.initials: S
authors.lastname: Funakoshi
authors.forename: S
authors.initials: S
authors.lastname: Yamamoto
authors.forename: Y
authors.initials: Y
authors.lastname: Nakamura
authors.forename: H
authors.initials: H
authors.lastname: Ishii
authors.forename: T
authors.initials: T
authors.lastname: Hibi
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D003093:Colitis, Ulcerative / Q000188:drug therapy*; D005260:Female; D006801:Humans; D007413:Intestinal Mucosa / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D019804:Mesalamine / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D008875:Middle Aged; D012460:Sulfasalazine / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D012460:Sulfasalazine; D019804:Mesalamine