Evaluation of the IR Biotyper for Klebsiella pneumoniae typing and its potentials in hospital hygiene management

Klebsiella pneumoniae has emerged as one of the most important pathogens that frequently encounter in community-acquired or hospital-acquired infections. Timely epidemiological surveillance could greatly facilitate infection control of K. pneumoniae and many deadly pathogens alike. In this study, we evaluated the performance of the IR Biotyper, a Fourier transform infrared (FTIR) spectroscopy system for K. pneumoniae isolates typing through (i) optimizing the culture scheme and defining the cutoff value (COV) range and (ii) comparing with commonly used typing tools such as multi-locus sequence typing (MLST), pulsed-field gel electrophoresis (PFGE) and whole-genome sequencing (WGS). We found that a non-selective and non-chromogenic medium with 24 ± 2 h incubation gives the best discriminatory power for the IR Biotyper (IRBT). COV evaluation indicated that the IRBT is a robust typing method with good reproducibility. Besides, we observed that the modified H₂O-EtOH suspensions preparation method could enhance the quality of the spectrum, especially for those hypermucoviscous strains. For the method comparison study, our data demonstrated that FTIR spectroscopy could accurately cluster K. pneumoniae strains. The typing results of the IRBT were almost entirely in concordance with those from PFGE and WGS. Together with the advantages such as low costs and short turnaround time (less than 3h), the IRBT is a promising tool for strain typing that could make real-time outbreak investigation a reality.