Impact of the blue-carba rapid test for carbapenemase detection on turnaround time for an early therapy against Pseudomonas aeruginosa

• Published in: American journal of infection control 2021-03, Vol.49 (3), p.352-354
• Main Authors: da Cunha, Rick Shandler Rodrigues, Carniel, Eliana, Narvaez, Gabriel Azambuja, Dias, Cícero Gomes, Perez, Leandro Reus Rodrigues
• Format: Article
• Language: English
• Subjects: Antimicrobial stewardship; Carbapenem-resistance; Early intervention; Infection control; Phenotypic test
• ISSN: 0196-6553; 1527-3296
• DOI: 10.1016/j.ajic.2020.08.018

•Carbapenem-resistant Pseudomonas aeruginosa is a major concern.•Different resistance mechanisms to carbapenems may influence the therapeutic choice.•Blue-carba is an easy and feasible phenotypic test to detect carbapenemases.•Blue-carba anticipated in approximately 1.4 days the final antimicrobial susceptibility report.•Carbapenemase notification significantly reduced the time for a first intervention for antimicrobial adequacy as well as for better infection control management. To determine the turnaround time from a blue-carba result until a final microbiological report (bacterial identification plus antimicrobial susceptibility profile) and to infer the impact of an early therapeutic intervention based on the blue-carba results. Pseudomonas aeruginosa isolates were recovered from hospitalized patients from Porto Alegre, Brazil, and tested by blue-carba test. Time required for a blue-carba result, right after the sample processing, was compared with those required to get final report (specie identification and antimicrobial susceptibility profile) Isolates blue-carba positive were tested by phenotypically and genotypically for Klebsiella pneumoniae carbapenemase and metallo-β-lactamase genes. A total of 199 isolates were analyzed and 23 (11.6%) were blue-carba positive and harboring the blaSPM-1-like gene. Fifty-two (26.1%) isolates were blue-carba negative but resistant to meropenem and/or imipenem. Polymyxin B and ceftolozane/tazobactam (this latter except for SPM-1 producers) were 100% active for all P. aeruginosa isolates, a blue-carba test allow an earlier intervention or adequacy of therapy. Early adequacy can be promoted by blue-carba test for 11.6% of SPM-1-producing P. aeruginosa isolates, polymyxin B could be prior associated and ceftolozane/tazobactam withdrawn from therapy. For the remaining isolates, empirical therapy involving ceftolozane/tazobactam can be maintained with greater likelihood of adequacy. An active communication between laboratory and clinical services is necessary to better explore these earlier blue-carba results, significantly reducing the time for a first intervention.