title: The leukocyte count predicts the efficacy of treatment with azathioprine in inflammatory bowel disease.
abstract: BACKGROUND
  Azathioprine has variable efficacy in inflammatory bowel disease. Previous studies suggested that either neutropenia, an increase in the mean corpuscular volume, the assessment of thiopurine methyl-transferase activity or erythrocyte 6-thioguanine values might predict the treatment response. However, due to the conflicting results of the preceding studies there are yet no established laboratory values which allow an estimation of the clinical response.
  
  
  METHODS
  45 patients with Crohn's disease and 39 patients with ulcerative colitis were enrolled in this retrospective evaluation. After a minimum of six months therapy with azathioprine patients in remission were compared with those who did not achieve a stable remission with respect to the number of leucocytes, lymphocytes, neutrophil granulocytes and the mean corpuscular volume.
  
  
  RESULTS
  Patients who went into remission during treatment with azathioprine displayed significantly lower leukocyte counts if compared to patients who were not in remission (p = 0.004 in Crohn's disease and 0.003 in ulcerative colitis). A similar tendency was also observed with respect to the granulocyte count (p = 0.007 in Crohn's disease and 0.004 in ulcerative colitis). The mean corpuscular volume did not correlate with the response to purine analogues.
  
  
  CONCLUSIONS
  The absolute leukocyte count and the percentage of granulocytes seem to predict the response to purine analogues in inflammatory bowel disease and possibly offers a feasible and cost effective diagnostic tool for the assessment of therapeutic efficacy. Subsequent preferably prospective studies should aim to define the optimal cut-off value for the leukocyte count.
authors.affiliation: Medizinische Poliklinik - Innenstadt, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Glas
authors.forename: H-P
authors.initials: HP
authors.lastname: Török
authors.forename: J
authors.initials: J
authors.lastname: Daczo
authors.forename: L
authors.initials: L
authors.lastname: Tonenchi
authors.forename: M
authors.initials: M
authors.lastname: Folwaczny
authors.forename: Christian
authors.initials: C
authors.lastname: Folwaczny
mesh_terms: D000328:Adult; D001379:Azathioprine / Q000627:therapeutic use*; D003093:Colitis, Ulcerative / Q000097:blood / Q000188:drug therapy* / Q000473:pathology; D003424:Crohn Disease / Q000097:blood / Q000188:drug therapy* / Q000473:pathology; D005260:Female; D006098:Granulocytes / Q000187:drug effects; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D007958:Leukocyte Count; D007962:Leukocytes / Q000187:drug effects*; D008297:Male; D008499:Medical Records; D012074:Remission Induction; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D007166:Immunosuppressive Agents; D001379:Azathioprine