© The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. Background: It has been suggested that there is an increased risk of treatment failure in episodes of MRSA bloodstreaminfection (BSI) caused by strains with high vancomycin MICs. However, it is unknown if this phenomenonmay also act as a risk factor for the development of infective endocarditis (IE).Methods: We analysed 207 episodes of catheter-related (CR)-BSI recruited from June 2008 to December 2009within 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 investigatedby Cox regression.Results: 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 antistaphylococcalagents [16 (7.7%)]. Haematogenous complications occurred in 41 patients (19.8%), including 10 episodes complicatedby IE. Early (48 h) and late (30 day) all-cause mortality were 3.4% and 25.1%, respectively. High vancomycinMIC isolates were more common among patients that developed IE compared with those free from thiscomplication [90.9% (9/10) versus 44.7%(88/197); P=0.007]. This association remained significant after adjustingfor multiple confounders (including initial antibiotic therapy and catheter removal) in different models (minimumhazard ratio: 9.18; 95% CI: 1.16-72.78; P=0.036). There were no differences in mortality according tovancomycin MIC values.Conclusions: Decreased susceptibility to vancomycin acted as a predictor of the development of IE complicatingMRSA CR-BSI.
|Journal||Journal of Antimicrobial Chemotherapy|
|Publication status||Published - 1 Jul 2017|