Background: S. aureus bacteremia is associated with high morbidity and mortality. Standard of care utilizes empiric coverage with broad spectrum antibiotics such as vancomycin until MRSA is excluded. Prompt communication of gram stains (GS), organism identification (ID), and susceptibility results should allow faster use of targeted therapy. We sequentially evaluated 2 methods of reporting positive blood cultures (pBCs) for gram-positive cocci in clusters (GPCCL).
Methods: We conducted a prospective study of BC reporting at Robert Wood Johnson University Hospital from 2/1/14 – 12/31/14. pBCs with GPCCL on GS were called to the patient's primary nurse (pRN) (standard practice). From 2/1/14-7/22/14, intervention (INT) 1 was conducted in which ID and direct susceptibility testing (dAST) from the pBC vial was done, and ~ 24 hours later, the pRN was called with the results (MSSA, MRSA, or CoNS).
In INT 2 (7/23/14-12/31/14), the GeneXpert MRSA/MSSA PCR method, with results in 1-2 h, replaced ID/dAST. PCR was performed as soon as GS results showed GPCCL, and the results (MSSA, MRSA, not S. aureus) were called to the pRN.
Electronic chart review on patients included in the rapid ID protocols was conducted to assess the time to report results of ID/dAST or PCR, and time to change in antibiotics.
We assessed time to ID from GS, time to directed therapy (DT), and length of stay (LOS). We then compared end points between each INT and pre-INT data (10/1/13-1/31/14).
Results: ID/dAST reduced the time to full ID of MSSA and MRSA by ~22 h and 29 h, respectively, and PCR reduced the times by ~48 h and 40 h respectively. However, there was little or no significant reduction in time to DT and LOS. See charts for further details.
Conclusion: There was improvement in mean time to ID from GS in both INT groups. However, the mean time to DT did not improve. The results suggest that an additional INT should be implemented wherein a stewardship team (STEW) contacts the responsible physician to suggest a change of therapy after review of dAST. Whether LOS can be reduced by rapid reporting will depend on the results of this added INT. We conclude that rapid reporting of MRSA, MSSA, and CoNS from pBCs is feasible, but the effect on patient care may require active INT by a STEW.
T. Bhowmick, None
J. Cornett, None
T. Kirn, None
M. Weinstein, None