title: Risk factors associated with high linezolid trough plasma concentrations.
abstract: OBJECTIVE
  The major concern of linezolid is the adverse events. High linezolid trough serum concentration (Cmin) has been associated with toxicity. The aim of this study was to analyze factors associated with high Cmin.
  
  
  METHODS
  Main clinical characteristics of 104 patients treated with 600 mg/12 hours of linezolid were retrospectively reviewed. Samples were obtained just before the next dose after at least three doses and within the first 8 days of treatment. High Cmin was considered when it was >8 mg/L. Univariate and multivariate analysis were performed.
  
  
  RESULTS
  34.6% patients had a Cmin >8 mg/L, and they were older and had more frequently an estimated glomerular filtration by MDRD <40 mL/min. There were more patients co-treated with rifampin in the group with low Cmin. The only factor independently associated with Cmin >8 was the renal function. Patients with an eGF < 40 mL/min had significantly higher Cmin than those with eGF > 80 mL/min (OR: 4.273) and there was a trend towards a high Cmin in patients with eGF between 40-80 mL/min (OR: 2.109).
  
  
  CONCLUSIONS
  High Cmin were frequent, especially in patients with MDRD <40 mL/min. Therapeutic drug monitoring could be useful to avoid toxicity in patients with renal dysfunction.
authors.affiliation: a Department of Infectious Diseases , Hospital Clínic of Barcelona , Barcelona , Spain.
authors.forename: L
authors.initials: L
authors.lastname: Morata
authors.affiliation: a Department of Infectious Diseases , Hospital Clínic of Barcelona , Barcelona , Spain.
authors.forename: C
authors.initials: C
authors.lastname: De la Calle
authors.affiliation: a Department of Infectious Diseases , Hospital Clínic of Barcelona , Barcelona , Spain.
authors.forename: J M
authors.initials: JM
authors.lastname: Gómez-Cerquera
authors.affiliation: a Department of Infectious Diseases , Hospital Clínic of Barcelona , Barcelona , Spain.
authors.forename: L
authors.initials: L
authors.lastname: Manzanedo
authors.affiliation: b Department of Pharmacology and Toxicology , Hospital Clínic of Barcelona , Barcelona , Spain.
authors.forename: G
authors.initials: G
authors.lastname: Casals
authors.affiliation: b Department of Pharmacology and Toxicology , Hospital Clínic of Barcelona , Barcelona , Spain.
authors.forename: M
authors.initials: M
authors.lastname: Brunet
authors.affiliation: a Department of Infectious Diseases , Hospital Clínic of Barcelona , Barcelona , Spain.
authors.forename: N
authors.initials: N
authors.lastname: Cobos-Trigueros
authors.affiliation: a Department of Infectious Diseases , Hospital Clínic of Barcelona , Barcelona , Spain.
authors.forename: J A
authors.initials: JA
authors.lastname: Martínez
authors.affiliation: a Department of Infectious Diseases , Hospital Clínic of Barcelona , Barcelona , Spain.
authors.forename: J
authors.initials: J
authors.lastname: Mensa
authors.affiliation: a Department of Infectious Diseases , Hospital Clínic of Barcelona , Barcelona , Spain.
authors.forename: A
authors.initials: A
authors.lastname: Soriano
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000009:adverse effects* / Q000097:blood* / Q000493:pharmacokinetics; D001424:Bacterial Infections / Q000097:blood / Q000188:drug therapy; D004305:Dose-Response Relationship, Drug; D016903:Drug Monitoring; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007674:Kidney Diseases / Q000097:blood / Q000139:chemically induced; D000069349:Linezolid / Q000008:administration & dosage / Q000009:adverse effects* / Q000097:blood* / Q000493:pharmacokinetics; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors
chemical_list: D000900:Anti-Bacterial Agents; D000069349:Linezolid
keywords: Glomerular filtration; linezolid; therapeutic drug monitoring; toxicity