Strategies to improve time to administration of appropriate, effective antimicrobial therapy can improve patient outcomes. We sought to retrospectively assess if the earlier identification of blood pathogens and their resistance determinants with multiplex PCR platforms could have an impact on time to initiate appropriate antimicrobial therapy.
All patients with monomicrobial positive blood cultures from March to June 2013 were included in the retrospective chart review analysis. We assessed time to effective therapy (time from positive blood culture Gram stain result to change in therapy), time to optimal therapy (time from Gram stain result to the final change in therapy based on susceptibility), and compared to time to targeted therapy (time from rapid multiplex PCR results to modification of therapy).
One hundred and forty-nine patients were included. The average time to effective therapy was 7.6 hours, and time to optimal therapy 52.3 hours. Time to targeted therapy would be 1.15-2.5 hours with availability of multiplex PCR results (P < 0.001). A total of 28 patients would have received targeted therapy (1 with CTX-M K. pneumoniae, 1 with KPC K. pneumoniae, 3 with MRSA, 20 with MSSA and 3 with VRE infection) in significantly less time.
Use of the rapid multiplex PCR systems, had the greatest potential to improve timeliness to appropriate therapy in the patients where the presence or absence of drug resistance markers such as mecA, vanA/B, CTX-M, and KPC was determined.