title: Higher clinical success in patients with ventilator-associated pneumonia due to methicillin-resistant Staphylococcus aureus treated with linezolid compared with vancomycin: results from the IMPACT-HAP study.
abstract: BACKGROUND
  Controversy exists regarding optimal treatment for ventilator-associated pneumonia (VAP) due to methicillin-resistant Staphylococcus aureus (MRSA). The primary objective of this study was to compare clinical success of linezolid versus vancomycin for the treatment of patients with MRSA VAP.
  
  
  METHODS
  This was a multicenter, retrospective, observational study of patients with VAP (defined according to Centers for Disease Control and Prevention criteria) due to MRSA who were treated with linezolid or vancomycin. MRSA VAP was considered when MRSA was isolated from a tracheal aspirate or bronchoalveolar lavage. Clinical success was evaluated by assessing improvement or resolution of signs and symptoms of VAP by day 14. After matching on confounding factors, logistic regression models were used to determine if an association existed between treatment arm and clinical success.
  
  
  RESULTS
  A total of 188 patients were evaluated (101 treated with linezolid and 87 with vancomycin). The mean ± standard deviation Acute Physiology and Chronic Health Evaluation (APACHE) II score was 21 ± 11 for linezolid- and 19 ± 9 for vancomycin-treated patients (P = 0.041). Clinical success occurred in 85% of linezolid-treated patients compared with 69% of vancomycin-treated patients (P = 0.009). After adjusting for confounding factors, linezolid-treated patients were 24% more likely to experience clinical success than vancomycin-treated patients (P = 0.018).
  
  
  CONCLUSIONS
  This study adds to the evidence indicating that patients with MRSA VAP who are treated with linezolid are more likely to respond favorably compared with patients treated with vancomycin.
authors.forename: Paula
authors.initials: P
authors.lastname: Peyrani
authors.forename: Timothy L
authors.initials: TL
authors.lastname: Wiemken
authors.forename: Robert
authors.initials: R
authors.lastname: Kelley
authors.forename: Marcus J
authors.initials: MJ
authors.lastname: Zervos
authors.forename: Daniel H
authors.initials: DH
authors.lastname: Kett
authors.forename: Thomas M
authors.initials: TM
authors.lastname: File
authors.forename: Gary E
authors.initials: GE
authors.lastname: Stein
authors.forename: Kimbal D
authors.initials: KD
authors.lastname: Ford
authors.forename: Ernesto G
authors.initials: EG
authors.lastname: Scerpella
authors.forename: Verna
authors.initials: V
authors.lastname: Welch
authors.forename: Julio A
authors.initials: JA
authors.lastname: Ramirez
mesh_terms: D018806:APACHE; D000081:Acetamides / Q000009:adverse effects / Q000627:therapeutic use*; D000328:Adult; D000740:Anemia / Q000139:chemically induced; D000900:Anti-Bacterial Agents / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007674:Kidney Diseases / Q000139:chemically induced; D000069349:Linezolid; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus; D023303:Oxazolidinones / Q000009:adverse effects / Q000627:therapeutic use*; D053717:Pneumonia, Ventilator-Associated / Q000188:drug therapy* / Q000382:microbiology / Q000401:mortality; D012189:Retrospective Studies; D013921:Thrombocytopenia / Q000139:chemically induced; D016896:Treatment Outcome; D014640:Vancomycin / Q000009:adverse effects / Q000627:therapeutic use*
chemical_list: D000081:Acetamides; D000900:Anti-Bacterial Agents; D023303:Oxazolidinones; D014640:Vancomycin; D000069349:Linezolid