Abstract
The typing of epidemic bacterial pathogens in hospitals relies on DNA-based, expensive, and time-consuming techniques, that are often limited to retrospective studies. However, the quick identification of epidemic pathogens in the routine of the microbiology laboratories would expedite infection control procedures that limit the contamination of new patients. IR Biotyper (Bruker Daltonics GmbH) is a new typing machine based on Fourier-transform infrared (FTIR) spectroscopy which generates spectra, aiming at typing the micro-organisms within 3 h. This technique discriminates the isolates by exploring the differences of the surface cell polysaccharides. In this work, we evaluated the ability of the FTIR spectroscopy to recognize Gram-negative bacilli clones responsible for hospital outbreaks. Isolates of Pseudomonas aeruginosa (n = 100), Klebsiella pneumoniae (n = 16), Enterobacter cloacae (n = 23), and Acinetobacter baumannii (n = 20) were typed by the reference methods Multi-Locus Sequence Typing (defining sequence types – STs) along with or without pulsed field gel electrophoresis (PFGE) (defining pulsotypes), and by FTIR spectroscopy. The congruence of FTIR spectroscopy clustering was compared to those of MLST and PFGE by Adjusted Rand index and Adjusted Wallace coefficient. We found that FTIR spectroscopy accurately clustered P. aeruginosa, K. pneumoniae, and E. cloacae isolates belonging to the same ST. The performance of the FTIR spectroscopy was slightly lower for A. baumannii. Furthermore, FTIR spectroscopy also correctly clustered P. aeruginosa isolates having a similar pulsotype. Overall, the IR Biotyper can quickly (in less than 3 h) detect the spread of clones of P. aeruginosa, K. pneumoniae, E. cloacae, and A. baumannii. The use of this technique by clinical microbiology laboratories may help to tackle the spread of epidemic clones by the quick implementation of infection control measures.
Highlights
Gram-negative bacilli are involved in the four most frequent healthcare-associated infections (Peleg and Hooper, 2010)
To assess the concordance between typings with multilocus sequence typing (MLST) and Fourier-transform infrared (FTIR) spectroscopy, Adjusted Rand index (AR) was calculated at different cut-off of clustering (Figure 1)
We found that FTIR spectroscopy can type isolates of Gram-negative bacilli responsible for hospital outbreaks in 3 h
Summary
Gram-negative bacilli are involved in the four most frequent healthcare-associated infections (i.e., urinary tract infections, surgical site infections, pneumonias, and bloodstream infections) (Peleg and Hooper, 2010). Infection control aims at limiting the spread of multidrug-resistant bacterial strains Such outbreaks could be controlled with reinforced hygiene control measures that are quickly implemented after early detection of cross-transmissions (Woodford et al, 2011). Pulsed-field gel electrophoresis (PFGE), which clusters the isolates at the clonal level after macrorestriction of the total DNA (Talon et al, 1996), has been used for decades and is still used to investigate local outbreaks. These highly accurate techniques are laborious, time consuming and require trained staff. A quick and reliable typing technique that detects pathogen cross-transmissions in the routine of the clinical microbiology laboratory is still needed
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
