Phenotypic demonstration of β-lactamase (ESβLs, MβLs, and Amp-C) among MDR Pseudomonas aeruginosa isolates obtained from burn wound infected in Yemen

Abstract

In 2017, the World Health Organization published its first-ever list of antimicrobial-resistant bacteria “priority pathogens,” a catalog of 12 families of bacteria posing the greatest threat to human health. This list focuses on the risk of Gram-negative bacteria for multiple drug-resistant. Pseudomonas aeruginosa was at the top of the list and critical. A current study aiming to demonstrate the prevalence of β-lactamase among multidrug-resistant P. aeruginosa strains isolated from burn wound patients phenotypically. The isolates were identified then antibiotic susceptibility tested against 10 antipseudomonal agents, finally, phenotypically β-lactamase (ESβLs, MβLs, and Amp-C) production screened by combined disk diffusion test and Imipenem-ethylenediaminetetraacetic acid. Results in the current study identified 98 P. aeruginosa isolates from 200 clinical specimens obtained from burn wound patients. Our result showed 65 (66.3%) of the 98 P. aeruginosa isolates were multiple drug-resistant (MDR) strains. Out of 65 isolates, 37 (56.9%), 21 (32.3%), and 40 (61.5%) were ESβLs, MβLs, and Amp-C producing P. aeruginosa, respectively, according to phenotypic detection method. We found co-expression of various β-lactamases. In the present study, 16 isolates showed co-existence of AmpC + ESBL, 16 isolates were having ESBL + MBL + AmpC, and five isolates were having co-existence of ESBL + MBL. The occurrence of ESβLs, MβLs, and Amp-C producing P. aeruginosa was demonstrated, calling for phenotypical determination of antibiotic resistance mechanisms should be performed regularly to guide antibiotic selection during therapy. Significant conclusions drawn from this work include a rise in the rate of β-lactamase (ESβLs, MβLs, and Amp-C) in MDR P. aeruginosa. Later research should, therefore, focus on the study of molecular characterization.