Rapid pathogen-specific phenotypic antibiotic susceptibility testing using digital LAMP quantification in clinical...

Area of Science:

• Microbiology
• Molecular Diagnostics
• Antimicrobial Resistance

Background:

• Urgent need for rapid antimicrobial susceptibility testing (AST) to guide treatment and curb antibiotic resistance.
• Current phenotypic AST methods are time-consuming, exceeding single patient visit durations.
• Antimicrobial resistance is a growing global health threat due to antibiotic misuse.

Purpose of the Study:

• To develop and validate a rapid phenotypic AST method for clinical samples.
• To achieve AST results within 30 minutes for informed clinical decision-making.
• To utilize digital nucleic acid quantification for precise measurement of bacterial response to antibiotics.

Main Methods:

• Developed an ultrafast digital real-time loop-mediated isothermal amplification (dLAMP) assay.
• Measured the phenotypic response of *Escherichia coli* in clinical urine samples to antibiotics.
• Utilized SlipChip microfluidic devices for sample processing and analysis.
• Compared dLAMP assay performance against a commercial digital polymerase chain reaction (dPCR) assay.

Main Results:

• Achieved AST results for *E. coli* in clinical urine samples in under 30 minutes.
• The dLAMP assay demonstrated high accuracy (AUC, 0.96) compared to dPCR (AUC, 0.98).
• Successfully measured phenotypic antibiotic susceptibility directly from clinical samples.

Conclusions:

• Rapid digital AST (dAST) using dLAMP is feasible for *E. coli* in urine samples.
• This technology enables faster clinical decisions and improves antimicrobial stewardship.
• Further development could extend dAST to other pathogens, antibiotics, and sample types.