Activity of imipenem/relebactam and comparators against KPC-producing Klebsiella pneumoniae and imipenem-resistant Pseudomonas aeruginosa.
Eur J Clin Microbiol Infect Dis
; 43(3): 445-457, 2024 Mar.
Article
en En
| MEDLINE
| ID: mdl-38157139
ABSTRACT
PURPOSE:
Relebactam is a novel ß-lactamase inhibitor, which, when combined with imipenem/cilastatin, is active against both class A and class C ß-lactamases. To evaluate in vitro antimicrobial activity of imipenem/relebactam against a collection of recent clinical isolates of carbapenem-non-susceptible P. aeruginosa and K. pneumoniae ST258 and ST512 KPC producers belonging to different lineages from hospitals in Southern Spain.METHODS:
Six hundred and seventy-eight isolates were tested 265 K. pneumoniae (230 ST512/KPC-3 and 35 ST258/KPC-3) and 413 carbapenem-non-susceptible P. aeruginosa. Imipenem, piperacillin/tazobactam, ceftazidime, cefepime, aztreonam, ceftolozane/tazobactam, meropenem, amikacin, ciprofloxacin, colistin, and ceftazidime/avibactam were used as comparators against P. aeruginosa. Against K. pneumoniae ceftazidime, cefepime, aztreonam, and ceftolozane/tazobactam were not tested, and tigecycline was studied instead. MICs were determined in duplicate by broth microdilution according to EUCAST guidelines.RESULTS:
Imipenem/relebactam displayed potent in vitro activity against both sequence types of KPC-3-producing K. pneumoniae. MIC50 and MIC90 values were 0.25 mg/L and 1 mg/L, respectively, with percent of susceptible isolates >97%. Only three K. pneumoniae ST512/KPC-3 isolates and one ST258/KPC-3 were resistant to imipenem/relebactam. Relebactam sensitized 98.5% of K. pneumoniae isolates resistant to imipenem. The activity of imipenem/relebactam against P. aeruginosa was moderate (susceptibility rate 62.7%). Analysis of the acquired and mutational resistome of isolates with high levels of resistance to imipenem/relebactam has not shown a clear association between them.CONCLUSION:
Imipenem/relebactam showed excellent activity against K. pneumoniae KPC-3. The activity of imipenem/relebactam against imipenem-resistant P. aeruginosa was moderate.Palabras clave
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Infecciones por Pseudomonas
/
Cefalosporinas
/
Imipenem
/
Compuestos de Azabiciclo
Límite:
Humans
Idioma:
En
Año:
2024
Tipo del documento:
Article