Impact of rapid diagnosis of Staphylococcus aureus bacteremia from positive blood cultures on patient management
We have performed a retrospective, before–after comparison of turnaround time and therapy adjustment parameters before and after the introduction of matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) plus mecA polymerase chain reaction (PCR) for the identification of methicillin-resistant Staphylococcus aureus (MRSA) in positive blood cultures. There were 227 episodes of S. aureus bacteremia during the study periods. The pre-MALDI-TOF and post-MALDI-TOF groups included 133 and 94 patients, respectively. The two rapid methods performed sequentially decreased the turnaround time of MRSA identification by nearly 50% (2.06 ± 1.95 vs. 3.95 ± 1.70 days). There was no significant reduction in the length of hospitalization (28.27 ± 32.16 vs. 28.62 ± 28.75 days). In both groups, the adequacy of the empirical antibacterial therapy was similar (59.49% vs. 51.31%), but the optimization of the therapy was more frequent in the post-MALDI-TOF group. Routine implementation of these techniques provides results earlier than conventional methods and increases the proportion of episodes with adequate change of empirical to directed antimicrobial therapy.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
This retrospective study is pending of approval by the ethical committee of the University Hospital La Paz.
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