title: Therapeutic drug monitoring based on early measurements of serum teicoplanin levels in Japanese patients.
abstract: BACKGROUND
  The serum level of teicoplanin (TEIC) is immediately elevated following administration of the recommended dose. In this study, the predictability of the serum trough for TEIC was investigated at day 2 or 3 (C(2-3)), and the authors performed a simulation based on the Bayesian method using C(2-3) in Japanese patients.
  
  
  METHODS
  Patients whose the serum trough level was measured within 48 hours (C(2-3)) and at steady state (Css) were eligible for the study. C(2-3) was compared with the predicted level based on the population mean method, and Css was compared with the predicted Css based on both the Bayesian method using C(2-3) and the population mean method. Bias and prediction accuracy were evaluated by the mean prediction error and the mean absolute prediction error (MAE), respectively.
  
  
  RESULTS
  The observed and predicted C(2-3) values were 13.2 ± 4.2 μg/mL and 10.4 ± 2.1 μg/mL, respectively. The observed Css was 17.1 ± 3.7 μg/mL, and the predicted Css values based on the Bayesian method and the population mean method were 16.8 ± 2.4 μg/mL and 15.3 ± 2.1 μg/mL, respectively. The mean prediction error and MAE for Css based on the population mean method were -1.87 μg/mL (not significant) and 3.45 μg/mL, respectively, and those based on the Bayesian method were -0.35 μg/mL (not significant) and 2.27 μg/mL, respectively. The change in MAE was 1.18 μg/mL (P < 0.05).
  
  
  CONCLUSIONS
  A simulation based on the Bayesian method using C(2-3) of TEIC is acceptable in clinical settings.
authors.affiliation: *Department of Pharmacy, Social Insurance Medical Association, Omuta Tenryo Hospital, Omuta-shi, Fukuoka, Japan; †Department of Pharmacy, Omuta City Hospital, Omuta-shi, Fukuoka, Japan; and ‡Department of Circulation, Social Insurance Medical Association, Omuta Tenryo Hospital, Omuta-shi, Fukuoka, Japan.
authors.forename: Kazutaka
authors.initials: K
authors.lastname: Oda
authors.forename: Takashi
authors.initials: T
authors.lastname: Kasada
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yoshikawa
authors.forename: Mitsunori
authors.initials: M
authors.lastname: Tanoue
authors.forename: Takuro
authors.initials: T
authors.lastname: Yamashita
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Takeshita
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000097:blood / Q000493:pharmacokinetics*; D001499:Bayes Theorem; D001835:Body Weight; D003198:Computer Simulation; D003404:Creatinine / Q000378:metabolism; D016903:Drug Monitoring / Q000379:methods*; D005260:Female; D006801:Humans; D007564:Japan; D008297:Male; D008657:Metabolic Clearance Rate; D008875:Middle Aged; D008954:Models, Biological; D017334:Teicoplanin / Q000097:blood / Q000493:pharmacokinetics*
chemical_list: D000900:Anti-Bacterial Agents; D017334:Teicoplanin; D003404:Creatinine