Prediction of Failure in Vancomycin-Treated Methicillin-Resistant Staphylococcus aureus Bloodstream Infection: A Clinically Useful Risk Stratification Tool.
Antimicrob Agents Chemother. 2011 Aug 8;
Authors: Moore CL, Lu M, Cheema F, Osaki-Kiyan P, Perri MB, Donabedian S, Haque NZ, Zervos MJ
Methicillin-resistant Staphylococcus aureus (MRSA) is a common cause of bloodstream infection (BSI), often associated with invasive infections and high rates of mortality. Vancomycin has remained the mainstay of therapy for serious Gram-positive infections, particularly MRSA BSI, however, therapeutic failures with vancomycin have been increasingly reported. We conducted a comprehensive evaluation of the factors (patient, strain, infection, treatment) involved in the etiology and management of MRSA BSI to create a risk stratification tool for clinicians. This study included consecutive patients with MRSA BSI treated with vancomycin over two years in an inner-city hospital in Detroit, MI. Classification and regression tree analysis (CART®) was used to develop a risk prediction model which characterized vancomycin-treated patients at high risk of clinical failure. Of all factors, APACHE-II score, with a cutoff point of 14, was found to be the strongest predictor of failure, thereafter splitting the population into two groups. Forty-seven percent of the population had an APACHE-II <14, which was associated with a low rate of clinical failure (11%) and mortality (4%). Fifty-four percent of the population had an APACHE-II ? 14, which was associated with a high rate of clinical failure (35%) and mortality (23%). The risk stratification model identified the interplay of three other predictors of failure including vancomycin MIC by Vitek® 2, risk level of the source of BSI and USA300 strain type. This model can be a useful tool for clinicians to predict the likelihood of success or failure in vancomycin-treated patients with MRSA bloodstream infection.
PMID: 21825294 [PubMed - as supplied by publisher]