Sedimentation field-flow fractionation for rapid phenotypic antimicrobial susceptibility testing: a pilot study

Area of Science:

• Microbiology
• Analytical Chemistry
• Clinical Diagnostics

Background:

• Antibiotic resistance poses a significant global public health threat.
• Rapid antimicrobial susceptibility testing (AST) is crucial for timely and effective antibiotic treatment.

Purpose of the Study:

• To assess sedimentation field-flow fractionation (SdFFF) as a rapid AST method.
• To achieve AST results in under 3 hours.

Main Methods:

• SdFFF analyzes early bacterial biophysical changes using chromatographic technology.
• One hundred clinical Escherichia coli strains were tested against five antibiotics.
• Comparison of retention times and elution profiles between treated and untreated bacteria determined susceptibility.

Main Results:

• SdFFF yielded AST results in less than 3 hours.
• High categorical agreement (99.8%), sensitivity (99.5%), and specificity (100.0%) were observed compared to broth microdilution.
• Performance metrics met ISO 20776-2 recommendations for antimicrobial testing.

Conclusions:

• Sedimentation field-flow fractionation (SdFFF) is a validated rapid phenotypic AST method.
• The technique offers accuracy and reliability with a turnaround time under 3 hours.
• SdFFF supports prompt clinical decisions in managing bacterial infections.