Typhoidal and para-typhoidal Salmonella are major causes of bacteraemia in resource-limited countries. Diagnostic alternatives to laborious and resource-demanding serotyping are essential. Fourier transform infrared spectroscopy (FTIRS) is a rapidly developing and simple bacterial typing technology. In this study, we assessed the discriminatory power of the FTIRS-based IR Biotyper (Bruker Daltonik GmbH, Bremen, Germany), for the rapid and reliable identification of biochemically confirmed typhoid and paratyphoid fever-associated Salmonella isolates. In total, 359 isolates, comprising 30 S. Typhi, 23 S. Paratyphi A, 23 S. Paratyphi B, and 7 S. Paratyphi C, respectively and other phylogenetically closely related Salmonella serovars belonging to the serogroups O:2, O:4, O:7 and O:9 were tested. The strains were derived from clinical, environmental and food samples collected at different European sites. Applying artificial neural networks, specific automated classifiers were built to discriminate typhoidal serovars from non-typhoidal serovars within each of the four serogroups. The accuracy of the classifiers was 99.9%, 87.0%, 99.5% and 99.0% for Salmonella Typhi, Salmonella Paratyphi A, B and Salmonella Paratyphi C, respectively. The IR Biotyper is a promising tool for fast and reliable detection of typhoidal Salmonella. Hence, IR biotyping may serve as a suitable alternative to conventional approaches for surveillance and diagnostic purposes.

Recently Candida auris has emerged as a multi-resistant fungal pathogen, with a significant clinical impact, and is able to persist for a long time on human skin and hospital environments. It is a critical issue on the WHO fungal priority list and therefore it is fundamental to reinforce hospital surveillance protocols to limit nosocomial outbreaks. The purpose of this study was to apply Fourier transform infrared spectroscopy (FT-IR) to investigate the phylogenetic relationships among isolated strains from a C. auris outbreak at the University Intensive Care Unit of a Tertiary University hospital in Turin (Italy). To calculate a clustering cut-off, intra- and inter-isolate, distance values were analysed. The data showed the presence of a major Alfa cluster and a minor Beta cluster with a defined C. auris clustering cut-off. The results were validated by an external C. auris strain and Principal Component and Linear Discriminant Analyses. The application of FT-IR technology allowed to obtain important information about the phylogenetic relationships between the analysed strains, defining for the first time a “not WGS-based” clustering cut-off with a statistical–mathematical approach. FT-IR could represent a valid alternative to molecular methods for the rapid and cost-saving typing of C. auris strains with important clinical implications.

Recently Candida auris has emerged as a multi-resistant fungal pathogen, with a significant clinical impact, and has become a critical issue in WHO fungal priority list, due to its unique ability to persist for long time on human skin and hospital environments. It is therefore fundamental to reinforce hospital surveillance protocols to limit nosocomial outbreaks. The study purpose was the Fourier-Transform Infrared Spectroscopy (FT-IR) application to investigate the phylogenetic relationships between isolated strains within the C. auris outbreak at the university Intensive Care Unit of a Tertiary University hospital in Turin (Italy). In order to calculate a clustering cut-off, intra- and inter-isolates distance values were analysed. Data showed the presence of a major cluster Alfa and a minor cluster Beta with a defined C. auris clustering cut-off. The results were validated by an external C. auris strain and Principal Component and Linear Discriminant Analysis. The application of FT-IR technology had allowed to obtain important information about the phylogenetic relationships between the analysed strains, defining for the first time a “not WGS-based” clustering cut-off with a statistical-mathematical approach. FT-IR could represent a valid alternative to molecular methods for rapid and cost saving typing of C. auris strains with important clinical implications.

Background and Aims: patients suffering from systemic mycobacterial spread are at high risk of unfavorable clinical outcomes. Rapid microbiological diagnosis, however, is complicated due to the very slow cultural growth of mycobacteria. To facilitate the diagnostic workflow, we assessed a workflow allowing mass spectrometry-based identification and molecular resistance testing of mycobacteria directly from blood culture pellets. Materials and Methods: for this study, 50 blood cultures spiked with n=10 Mycobacterium tuberculosis (MTC) isolates and n=40 isolates belonging to 12 other species of non-tuberculous mycobacteria (n=13 M. abscessus complex, n=5 M. avium, n=3 M. chimaera, n=5 M. fortuitum, n=5 M. intracellulare, n=2 M. lentiflavum and n=2 M. mucogenicum, n=1 for each one of the species M. elephantis, M. hassiacum, M. marseillense, M. nebraskense and M. parascrofulaceum) were used next to two clinical cases of a disseminated infection in HIV patients. Results: the application of the MBT Sepsityper® kit allowed the correct species level identification by applying mass spectrometry as well as correct molecular resistance testing results as compared to the diagnostic reference approach applied with mycobacterial culture material. Conclusions: in conclusion, the results provide a proof-of-principle of the suitability of the assessed potential workflow in order to achieve a shortened time-to-result for the diagnosis of systemic mycobacterial infections. Future studies in high endemicity settings are desirable to assess the clinical applicability and impact of such a shortened workflow.