title: High vancomycin MICs predict the development of infective endocarditis in patients with catheter-related bacteraemia due to methicillin-resistant Staphylococcus aureus.
abstract: It has been suggested that there is an increased risk of treatment failure in episodes of MRSA bloodstream infection (BSI) caused by strains with high vancomycin MICs. However, it is unknown if this phenomenon may also act as a risk factor for the development of infective endocarditis (IE).
  
  
  
  We analysed 207 episodes of catheter-related (CR)-BSI recruited from June 2008 to December 2009 within a prospective study on MRSA BSI in 21 Spanish hospitals. Vancomycin susceptibility was centrally tested. The impact of high vancomycin MIC values (≥1.5 mg/L by Etest) on the subsequent development of IE was investigated by Cox regression.
  
  
  
  High vancomycin MIC values were observed in 46.9% of the isolates. Initial therapy consisted of vancomycin [99 episodes (44.7%)], daptomycin [25 (12.1%)], linezolid [18 (8.7%)] and other antistaphylococcal agents [16 (7.7%)]. Haematogenous complications occurred in 41 patients (19.8%), including 10 episodes complicated by IE. Early (48 h) and late (30 day) all-cause mortality were 3.4% and 25.1%, respectively. High vancomycin MIC isolates were more common among patients that developed IE compared with those free from this complication [90.9% (9/10) versus 44.7% (88/197); P  = 0.007]. This association remained significant after adjusting for multiple confounders (including initial antibiotic therapy and catheter removal) in different models (minimum hazard ratio: 9.18; 95% CI: 1.16-72.78; P  = 0.036). There were no differences in mortality according to vancomycin MIC values.
  
  
  
  Decreased susceptibility to vancomycin acted as a predictor of the development of IE complicating MRSA CR-BSI.
authors.affiliation: Unit of Infectious Diseases, Hospital Universitario '12 de Octubre', Instituto de Investigación Hospital '12 de Octubre' (i?+?12), Universidad Complutense, Madrid, Spain.
authors.forename: Rafael
authors.initials: R
authors.lastname: San-Juan
authors.affiliation: Unit of Infectious Diseases, Hospital Universitario '12 de Octubre', Instituto de Investigación Hospital '12 de Octubre' (i?+?12), Universidad Complutense, Madrid, Spain.
authors.forename: Mario
authors.initials: M
authors.lastname: Fernández-Ruiz
authors.affiliation: Department of Infectious Diseases, Corporació Sanitària Parc Taulí, Sabadell, Spain.
authors.forename: Oriol
authors.initials: O
authors.lastname: Gasch
authors.affiliation: Department of Microbiology, Hospital Universitari de Bellvitge, Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain.
authors.forename: Mariana
authors.initials: M
authors.lastname: Camoez
authors.affiliation: Unit of Infectious Diseases, Hospital Universitario '12 de Octubre', Instituto de Investigación Hospital '12 de Octubre' (i?+?12), Universidad Complutense, Madrid, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: López-Medrano
authors.affiliation: Department of Microbiology, Hospital Universitari de Bellvitge, Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain.
authors.forename: María Ángeles
authors.initials: MÁ
authors.lastname: Domínguez
authors.affiliation: Department of Infectious Diseases, Hospital Universitari Vall d'Hebron, Universitat Autònoma de Barcelona, Barcelona, Spain.
authors.forename: Benito
authors.initials: B
authors.lastname: Almirante
authors.affiliation: Department of Clinical Microbiology and Infectious Diseases, Hospital General Universitario 'Gregorio Marañón', Universidad Complutense, Madrid, Spain.
authors.forename: Belén
authors.initials: B
authors.lastname: Padilla
authors.affiliation: Department of Infectious Diseases, Hospital Universitari de Bellvitge, Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain.
authors.forename: Miquel
authors.initials: M
authors.lastname: Pujol
authors.affiliation: Unit of Infectious Diseases, Hospital Universitario '12 de Octubre', Instituto de Investigación Hospital '12 de Octubre' (i?+?12), Universidad Complutense, Madrid, Spain.
authors.forename: José María
authors.initials: JM
authors.lastname: Aguado
mesh_terms: D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D016470:Bacteremia / Q000188:drug therapy* / Q000382:microbiology; D055499:Catheter-Related Infections / Q000150:complications* / Q000188:drug therapy / Q000382:microbiology; D052978:Disk Diffusion Antimicrobial Tests; D004696:Endocarditis / Q000382:microbiology* / Q000401:mortality; D005260:Female; D006801:Humans; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects* / Q000302:isolation & purification; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D011446:Prospective Studies; D012044:Regression Analysis; D012307:Risk Factors; D013203:Staphylococcal Infections / Q000188:drug therapy* / Q000382:microbiology / Q000401:mortality; D014640:Vancomycin / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D014640:Vancomycin