Risk of target non-attainment in obese compared to non-obese patients in calculated linezolid therapy.
Clin Microbiol Infect
; 26(9): 1222-1228, 2020 Sep.
Article
em En
| MEDLINE
| ID: mdl-32311473
ABSTRACT
OBJECTIVES:
The aim was to characterize linezolid population pharmacokinetics in plasma and interstitial space fluid of subcutaneous adipose tissue (target site) of obese compared with non-obese patients and to determine dosing regimens enabling adequate therapy using Monte Carlo simulations.METHODS:
In this prospective, parallel group, open-label, controlled, single-centre trial, 30 surgery patients (15 obese, 15 non-obese) received 600 mg of intravenous linezolid. A population pharmacokinetic analysis characterizing plasma and microdialysis-derived target site pharmacokinetics was followed by Monte Carlo simulations using twice/thrice daily 600-1200 mg short-term and extended infusions of linezolid. Adequacy of therapy was assessed by the probability of pharmacokinetic/pharmacodynamic target attainment for time and exposure-related indices.RESULTS:
In the model, lean body weight and obesity status largely explained between-patient variability in linezolid PK parameters (12.0-44.9%). Both factors caused lower area under the concentration-time curve in typical obese patients in plasma (-20.4%, 95% CI -22.0% to -15.9%) and at target-site (-37.7%, 95% CI -47.1% to -24.2%) compared with non-obese patients. Probability of target attainment showed improvement with increasing linezolid doses. Depending on lean body weight, adequate therapy was partially attained for 900- and 1200-mg linezolid doses and minimum inhibitory concentrations (MICs) ≤2 mg/L (probability of target attainment 62.5-100%) but could not be reached for MIC = 4 mg/L (probability of target attainment ≤82.3%). Additionally, lower linezolid distribution into the target site in obese patients as described above might compromise the plasma-based probability of target attainment analysis.DISCUSSION:
This analysis revealed risks of linezolid underdosing in empirical antibiotic therapy of most resistant bacteria for obese and non-obese patients. Doubling the standard dose is associated with adequate probability of target attainment throughout most body masses for MIC ≤2 mg/L. Further clinical studies with adjusted dosing regimens in for example intensive care patients are needed.Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Linezolida
/
Antibacterianos
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Obesidade
Tipo de estudo:
Clinical_trials
/
Etiology_studies
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Prognostic_studies
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Risk_factors_studies
Limite:
Adult
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Aged
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Female
/
Humans
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Male
/
Middle aged
Idioma:
En
Revista:
Clin Microbiol Infect
Assunto da revista:
DOENCAS TRANSMISSIVEIS
/
MICROBIOLOGIA
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
Alemanha