MỨC ĐỘ NHẠY CẢM VỚI KHÁNG SINH MỚI CEFTAZIDIME/AVIBACTAM VÀ CEFTOLOZANE/TAZOBACTAM CỦA CÁC CHỦNG KLEBSIELLA PNEUMONIAE VÀ PSEUDOMONAS AERUGINOSA KHÁNG CARBAPENEM

Abstract

Objectives: To determine the in vitro susceptibility to CZA and C/T of carbapenem-resistant P. aeruginosa (CRPA) and K. pneumoniae (CRKP) isolates negative for class B carbapenemase-encoding genes, isolated at Hanoi Medical University Hospital from 2021 to 2024.

Methods: A cross-sectional descriptive study was conducted on 322 CRPA and 401 CRKP strains isolated and archived at the Microbiology Department, Hanoi Medical University Hospital. Carbapenemase-encoding genes (blaKPC, blaNDM, blaVIM, blaIMP, blaOXA-48) were identified using PCR. Isolates negative for class B carbapenemase-encoding genes (blaNDM, blaVIM, blaIMP) underwent antimicrobial susceptibility testing using the disk diffusion method for CZA and C/T (for P. aeruginosa) and CZA (for K. pneumoniae).

Results: A total of 114/322 P. aeruginosa strains and 152/401 K. pneumoniae strains negative for class B carbapenemase genes were tested. For P. aeruginosa, the susceptibility rates to C/T and CZA were 42.1% and 62.3%, respectively. For K. pneumoniae, the susceptibility rate to CZA was 75.7%. Notably, P. aeruginosa and K. pneumoniae strains carrying only the blaKPC gene demonstrated high susceptibility rates to CZA, at 88% and 91.1%, respectively.

Conclusion: Ceftolozane/tazobactam and ceftazidime/avibactam remain potential treatment options for carbapenem-resistant P. aeruginosa and K. pneumoniae. However, the selection of antibiotics should be guided by antibiotic susceptibility testing and identification of carbapenemases.