Clinical impact of implementation of rapid diagnostic testing of blood cultures with Staphylococcus aureus on patient outcomes.

Gritte, Anndee S; Morneau, Kathleen M; Frei, Christopher R; Cadena-Zuluaga, Jose A; Walter, Elizabeth A; Hopkins, Teri L

Rapid diagnostic testing in microbiology labs shortens the time to identification of bacteria in blood cultures. Cepheid® GeneXpert® MRSA/SA PCR can be used to distinguish MRSA and MSSA from non-Staphylococcus aureus organisms in blood cultures. This study aims to determine if implementation of MRSA/SA PCR for blood culture pathogen identification, plus daily antimicrobial stewardship intervention, can reduce time to appropriate therapy, vancomycin duration, 30 day mortality, and 90 day recurrence in veterans. A total of 113 patients in the pre-implementation cohort and 73 patients in the post-implementation cohort were evaluated. Time to appropriate therapy was decreased from 49.8 (pre-implementation) to 20.6 (post-implementation) hours. There was a numerically shorter median duration of vancomycin therapy in the post-implementation group. There was no difference in 30 day mortality or 90 day recurrence between groups. Use of MRSA/SA PCR can improve antimicrobial use when combined with once-daily antimicrobial stewardship review.