Performance Comparison Between Fourier-Transform Infrared Spectroscopy-based IR Biotyper and Matrix-Assisted Laser...

Area of Science:

• Microbiology
• Molecular Biology
• Infectious Diseases

Background:

• Routine evaluation of bacterial strain clonality is crucial for microbiology laboratories.
• Existing methods require comparison for discriminatory power and accessibility.
• Fourier-transform infrared (FTIR) spectroscopy-based IR Biotyper offers a potential new approach.

Purpose of the Study:

• To compare the discriminatory power of IR Biotyper and MALDI-TOF MS for bacterial strain typing.
• To validate these methods against whole-genome sequencing (WGS) as the reference standard.
• To assess the accessibility and utility of IR Biotyper in routine laboratory settings.

Main Methods:

• Eighty-three extended-spectrum β-lactamase-producing *Escherichia coli* isolates were analyzed.
• Methods employed included whole-genome sequencing (WGS), MALDI-TOF MS, and IR Biotyper.
• Discriminatory power was assessed using Simpson's diversity index (SDI) and adjusted Rand index (aRI).

Main Results:

• IR Biotyper demonstrated a Simpson's diversity index (SDI) of 0.974, comparable to WGS (0.969).
• MALDI-TOF MS showed a lower SDI of 0.865, indicating reduced discriminatory power.
• Concordance with WGS improved significantly from 66.3% (MALDI-TOF MS) to 84.3% (IR Biotyper).

Conclusions:

• IR Biotyper offers improved discriminatory power for bacterial strain typing compared to MALDI-TOF MS.
• The method is accessible and suitable for evaluating strain clonality in routine diagnostics.
• IR Biotyper can aid epidemiological analysis and research on resistant bacteria transmission.