Adding Advanced Molecular Techniques to Standard Blood Cultures May Improve Patient Outcomes
Clinical question: Does the addition of rapid multiplex polymerase chain reaction molecular techniques to standard blood culture bottle (BCB) processing, with or without antimicrobial stewardship recommendations, affect antimicrobial utilization and patient outcomes?
Background: Standard BCB processing typically requires two days to provide identification and susceptibility testing results. PCR-based molecular testing is available to test positive BCB and deliver specific susceptibility results more rapidly, typically within one hour. Earlier results could improve antimicrobial utilization, limit antimicrobial resistance, decrease the risk of Clostridium difficile colitis, improve patient outcomes, and decrease healthcare costs. The impact of these techniques on outcomes is uncertain.
Study design: Prospective, randomized controlled trial (RCT).
Setting: Single large tertiary academic medical center.
Synopsis: Nearly 750 patients were randomized to conventional BCB processing (control), BCB with rapid multiplex PCR and templated recommendations (rmPCR), or BCB with rapid multiplex PCR and real-time antimicrobial stewardship provided by an infectious disease physician or specially trained pharmacist (rmPCR/AS). Time to microorganism identification was reduced from 22.3 hours in the control arm to 1.3 hours in the intervention arms. Both intervention groups had decreased use of broad spectrum piperacillin-tazobactam, increased use of narrow spectrum β-lactam, and decreased treatment of contaminants. Time to appropriate empiric treatment modification was shortest in the rmPCR/AS group.
Groups did not differ in mortality, length of stay, or cost, although an adequately powered study may show beneficial effects in these outcomes.
Bottom line: The addition of rapid multiplex PCR, ideally combined with antimicrobial stewardship, improves antimicrobial utilization in patients with positive blood cultures.
Citation: Banerjee R, Teng CB, Cunningham SA, et al. Randomized trial of rapid multiplex polymerase chain reaction-based blood culture identification and susceptibility testing. Clin Infect Dis. 2015;61(7):1071-1080.
