[Rapid detection of extended-spectrum beta-lactamases by flow cytometry method]

Area of Science:

• Microbiology
• Molecular Biology
• Biotechnology

Context:

• Extended-spectrum beta-lactamases (ESBL) confer resistance to crucial cephalosporin antibiotics in Enterobacteriaceae.
• Current ESBL detection methods are time-consuming, delaying critical treatment and infection control decisions.
• Rapid and accurate ESBL detection is vital for effective antimicrobial stewardship.

Purpose:

• To develop and validate a rapid flow cytometry-based assay for detecting ESBL production in Enterobacteriaceae.
• To compare the efficacy of flow cytometry with conventional methods for ESBL identification.
• To assess the utility of specific flow cytometry-derived indices (CTX-CLA and CAZ-CLA) for ESBL detection.

Summary:

• A flow cytometry assay was developed using a combination of cephalosporins (ceftazidime/cefotaxime) and clavulanic acid.
• The assay measured cell death percentages to calculate CLA index values, differentiating ESBL-producing from non-producing strains.
• Genotypic analysis confirmed the presence of ESBL genes in most ESBL-positive isolates, correlating with flow cytometry results.

Impact:

• Flow cytometry provides a significantly faster and reliable method for ESBL detection compared to traditional techniques.
• This rapid detection can lead to quicker implementation of appropriate antibiotic therapy.
• The study highlights the potential of flow cytometry to enhance clinical microbiology laboratory workflows and patient outcomes.