Acquired Ibla/I[sub.VIM] and Ibla/I[sub.GES] Carbapenemase-Encoding Genes in IPseudomonas aeruginosa/I: A Seven-Year Survey Highlighting an Increasing Epidemiological Threat

• Published in: Pathogens (Basel) Vol. 12; no. 10
• Main Authors: Martínez-Zavaleta, María Guadalupe, Fernández-Rodríguez, Diana, Hernández-Durán, Melissa, Colín-Castro, Claudia A, de Lourdes García-Hernández, María, Becerra-Lobato, Noé, Franco-Cendejas, Rafael, López-Jácome, Luis Esaú
• Format: Journal Article
• Language: English
• Published: MDPI AG 01-10-2023
• Subjects: Analysis; Control; Disease susceptibility; Drug resistance in microorganisms; Identification and classification; Prevention; Pseudomonas aeruginosa; Mexico
• ISSN: 2076-0817; 2076-0817
• DOI: 10.3390/pathogens12101256

(1) Background: Pseudomonas aeruginosa is a Gram-negative bacterium with several intrinsic and acquired antimicrobial resistance mechanisms. The spread of carbapenemase-encoding genes, an acquired mechanism, enables carbapenem resistance in clinical settings. Detection of the carbapenemase-producer strains is urgent. Therefore, we aimed to characterize carbapenemase production in the clinical strains of P. aeruginosa at a tertiary-care center. (2) Methods: We included clinical strains of P. aeruginosa (from August 2011 to December 2018) with resistance towards at least one carbapenem. Strains were isolated in a tertiary-care center in Mexico City. Antimicrobial susceptibility profiles were determined by broth microdilution. Screening for carbapenemase-encoding genes was performed in all strains. Phenotypic assays (CarbaNP and mCIM) were conducted. Additional modifications to mCIM were also tested. (3) Results: One-hundred seventy-one P. aeruginosa strains out of 192 included in this study were resistant towards at least one of the carbapenems tested. Forty-seven of these strains harbored a carbapenemase-encoding gene. VIM (59.6%) and GES (23.4%) were the most frequently found carbapenemases in our study, followed by IMP (14.9%). (4) Among the most frequent carbapenemase genes identified, metallo-ß-lactamases were the most prevalent, which impair new treatment options. Searching for carbapenemase genes should be performed in resistant isolates to stop transmission and guide antimicrobial treatment.