title: Tioguanine in patients with Crohn's disease intolerant or resistant to azathioprine/mercaptopurine.
abstract: BACKGROUND
  Tioguanine (TG) is an antimetabolite which may be regarded as an alternative to azathioprine (AZA)/mercaptopurine (MP) in patients with inflammatory bowel diseases.
  
  
  OBJECTIVE
  : To evaluate the tolerance and efficacy of TG in patients with Crohn's disease, intolerant or resistant to AZA/MP.
  
  
  METHODS
  An open prospective study was made on Crohn's disease patients treated with TG. Intolerance to AZA/MP was defined as a reaction occurring within 1 month after introduction of AZA/MP, including pancreatitis, abdominal pain, fever, arthralgia, myalgia, cutaneous rash, fatigue, alopecia, hepatitis and digestive intolerance. Resistance to AZA/MP was defined as the persistence of activity after at least 3 months of AZA/MP therapy.
  
  
  RESULTS
  Forty-nine Crohn's disease patients (36 women, 13 men; intolerance: n = 39; resistance: n= 10) were treated with TG (20 mg/day). Clinical pancreatitis did not recur under TG. Five patients (10%) had to stop TG due to intolerant reactions observed 13-21 days after TG was started. No haematological side-effects were observed under TG. The probability of clinical remission without corticosteroids or infliximab at 6 and 12 months was 46% and 79%, respectively, in the 40 patients with active disease at baseline. The probability of clinical relapse during maintenance TG therapy at 6 and 12 months was 29% and 53%, respectively, in the 28 patients in remission at baseline or who had achieved remission on TG.
  
  
  CONCLUSIONS
  TG is a possible alternative treatment in Crohn's disease patients, intolerant (especially for pancreatitis) or resistant to AZA/MP.
authors.affiliation: Département d'Hépato-Gastroentérologie, CHU de Grenoble, France. Bruno.Bonaz@uif-grenoble.fr
authors.forename: B
authors.initials: B
authors.lastname: Bonaz
authors.forename: J
authors.initials: J
authors.lastname: Boitard
authors.forename: P
authors.initials: P
authors.lastname: Marteau
authors.forename: M
authors.initials: M
authors.lastname: Lémann
authors.forename: B
authors.initials: B
authors.lastname: Coffin
authors.forename: B
authors.initials: B
authors.lastname: Flourié
authors.forename: J
authors.initials: J
authors.lastname: Belaiche
authors.forename: G
authors.initials: G
authors.lastname: Cadiot
authors.forename: E-H
authors.initials: EH
authors.lastname: Metman
authors.forename: A
authors.initials: A
authors.lastname: Cortot
authors.forename: J-F
authors.initials: JF
authors.lastname: Colombel
mesh_terms: D000328:Adult; D000963:Antimetabolites / Q000627:therapeutic use*; D001379:Azathioprine / Q000627:therapeutic use*; D003424:Crohn Disease / Q000188:drug therapy*; D004351:Drug Resistance; D005260:Female; D006801:Humans; D008297:Male; D015122:Mercaptopurine / Q000627:therapeutic use*; D008875:Middle Aged; D011446:Prospective Studies; D012008:Recurrence; D012074:Remission Induction; D013866:Thioguanine / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D000963:Antimetabolites; D015122:Mercaptopurine; D013866:Thioguanine; D001379:Azathioprine