Rapid antibiotic susceptibility testing and species identification for mixed samples

Area of Science:

• Microfluidics
• Antimicrobial Resistance
• Molecular Diagnostics

Background:

• Antimicrobial resistance (AMR) is a growing global health crisis, necessitating rapid diagnostic tools.
• Current phenotypic antibiotic susceptibility testing (AST) often lacks species identification, hindering targeted treatment.
• Existing methods require lengthy culturing or plating when species identification is crucial for accurate AST.

Purpose of the Study:

• To develop a rapid, single-cell phenotypic AST method integrated with species identification.
• To enable accurate susceptibility profiling of individual species within mixed microbial samples.
• To reduce the time required for AST from days to hours.

Main Methods:

• A microfluidic chip was engineered to perform phenotypic AST at the single-cell level.
• Fluorescence in situ hybridization (FISH) was employed for in situ genotyping of individual cells.
• The method was validated using four antibiotics against mixed samples containing seven bacterial species.

Main Results:

• Phenotypic AST was successfully performed on single cells within a microfluidic device.
• The integrated approach allowed for species identification and susceptibility determination simultaneously.
• Accurate species-specific susceptibility profiles were obtained for mixed samples in approximately 2 hours.

Conclusions:

• This novel microfluidic method enables rapid, single-cell phenotypic AST with concurrent species identification.
• The technique significantly reduces turnaround time for AST, facilitating timely clinical decision-making.
• This approach holds promise for personalized antibiotic prescriptions in high-resistance environments.