title: Vancomycin versus linezolid in the treatment of methicillin-resistant Staphylococcus aureus meningitis in an experimental rabbit model.
abstract: BACKGROUND
  The aim of this study was to compare the antibacterial efficacy of vancomycin and linezolid in a rabbit model of methicillin-resistant Staphylococcus aureus (MRSA) meningitis.
  
  
  METHODS
  Meningitis was induced by intracisternal inoculation of ATCC 43300 strain. After 16 h incubation time and development of meningitis, the vancomycin group received vancomycin 20 mg/kg every 12 h. The linezolid-10 and linezolid-20 groups received linezolid in 10 and 20 mg/kg dosages every 12 h, respectively. The control group did not receive any antibiotics. Cerebrospinal fluid bacterial counts were measured at the end of 16-h incubation time and at the end of 24-h treatment.
  
  
  RESULTS
  Bacterial counts were similar in all groups at 16 h. At the end of treatment the decrease in bacterial counts in the vancomycin group was approximately 2 logs higher than the linezolid-20 group (p>0.05) and approximately 4 logs higher than in the linezolid-10 group (p: 0.037) (Vancomycin group: -2.860 ± 4.495 versus Linezolid-20: -0.724 ± 4.360, versus Linezolid-10: 1.39 ± 3.37). Full or partial bacteriological response was higher in vancomycin versus linezolid-10 (p: 0.01), but not vancomycin versus linezolid-20 or linezolid-10 versus-linezolid-20 groups.
  
  
  CONCLUSIONS
  Our results suggest that linezolid is not statistically inferior to vancomycin in the treatment of MRSA meningitis in an experimental rabbit model in 20 mg/kg q12 h dosage; however, it is inferior in 10 mg/kg q12 h dosage. Additional data should gathered to confirm these findings in advance of clinical trials to assess efficacy in humans.
authors.affiliation: Department of Infectious Diseases and Clinical Microbiology, Urla State Hospital, Izmir, Turkey. sebnemozkoren@yahoo.com
authors.forename: Sebnem
authors.initials: S
authors.lastname: Calik
authors.forename: Tuncer
authors.initials: T
authors.lastname: Turhan
authors.forename: Taskin
authors.initials: T
authors.lastname: Yurtseven
authors.forename: Oguz Resat
authors.initials: OR
authors.lastname: Sipahi
authors.forename: Cagri
authors.initials: C
authors.lastname: Buke
mesh_terms: D000081:Acetamides / Q000494:pharmacology* / Q000627:therapeutic use*; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology / Q000627:therapeutic use; D015169:Colony Count, Microbial; D004195:Disease Models, Animal; D000069349:Linezolid; D016920:Meningitis, Bacterial / Q000188:drug therapy* / Q000382:microbiology; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects* / Q000254:growth & development; D023303:Oxazolidinones / Q000494:pharmacology* / Q000627:therapeutic use*; D011817:Rabbits; D013203:Staphylococcal Infections / Q000188:drug therapy* / Q000382:microbiology; D014640:Vancomycin / Q000494:pharmacology* / Q000627:therapeutic use*
chemical_list: D000081:Acetamides; D000900:Anti-Bacterial Agents; D023303:Oxazolidinones; D014640:Vancomycin; D000069349:Linezolid