title: Tacrolimus therapeutic drug monitoring in Tunisian renal transplant recipients: effect of post-transplantation period.
abstract: BACKGROUND
  Most previous studies having focused on therapeutic drug monitoring of tacrolimus in renal transplant recipients have assessed the clinical response of patients. The aim of this study is to investigate the influence of post-transplant delay on tacrolimus dose, trough levels (C0) and dose/C0 ratio in a Tunisian renal transplant population.
  
  
  METHODS
  A retrospective study including 110 renal transplant patients has been performed. Tacrolimus trough concentrations were adjusted according to the target range proposed by the European consensus conference on tacrolimus optimization. Samples for determination of tacrolimus blood level were subdivided according to the post-transplantation period into three groups.
  
  
  RESULTS
  The initial dose required was 0.17 ± 0.05 mg/kg/day during the first 3 months after transplantation. A reduction of 36 and 65% of tacrolimus initial dose during the second (3-12 months) and third period after transplantation (>12 months), respectively, was required to maintain the concentration level within therapeutic range. These results were different from those found in other studies performed in different populations. We hypothesize that these differences in dosing requirement may be due to an interethnic polymorphism in the expression of enzymes involved in tacrolimus metabolism.
  
  
  CONCLUSIONS
  These results could provide a simple therapeutic strategy to optimize tacrolimus prescription after renal transplantation in Tunisian population.
authors.affiliation: Service de Pharmacologie, Faculté de Médecine, Monastir, Tunisia. benfredj.nadia@gmail.com
authors.forename: N
authors.initials: N
authors.lastname: Ben Fredj
authors.forename: A
authors.initials: A
authors.lastname: Chaabane
authors.forename: Z
authors.initials: Z
authors.lastname: Chadly
authors.forename: M
authors.initials: M
authors.lastname: Hammouda
authors.forename: S
authors.initials: S
authors.lastname: Aloui
authors.forename: N A
authors.initials: NA
authors.lastname: Boughattas
authors.forename: H
authors.initials: H
authors.lastname: Skhiri
authors.forename: K
authors.initials: K
authors.lastname: Aouam
mesh_terms: D000328:Adult; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D016903:Drug Monitoring; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D016030:Kidney Transplantation; D008297:Male; D009173:Mycophenolic Acid / Q000627:therapeutic use; D011184:Postoperative Period; D011241:Prednisone / Q000627:therapeutic use; D012189:Retrospective Studies; D016559:Tacrolimus / Q000008:administration & dosage / Q000627:therapeutic use*; D014416:Tunisia
chemical_list: D007166:Immunosuppressive Agents; D009173:Mycophenolic Acid; D011241:Prednisone; D016559:Tacrolimus
keywords: Kidney transplantation; Post-transplantation time; Tacrolimus; Therapeutic drug monitoring