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Background: The aim of this study was to compare two different Bacterial Vaginosis diagnosis criteria, Nugent's score system and Hay/Ison criterion, by using Gram-stained vaginal smears. Materials and findings:Gram-stained smears were prepared with 10 µl and 30 µl of 100 vaginal samples, collected in ESwab ® , by the WASP ® automatic system. All smears were examined at 1000X magnification and assessed using both Nugent and Hay/Ison criteria. In addition, the presence of clue cells was recorded. All the slides were assessed by three independent expert readers in a blinded manner. Conclusions:The Hay/Ison criterion is a credible alternative to the Nugent's score system for the diagnosis of Bacterial Vaginosis. Furthermore, the combination of WASP ® automatic system and the Hay/Ison criterion can represent a fast and reliable workflow, especially in those laboratories where the request of vaginal culture tests is extremely high.

Aim: Carbapenemase-resistant Enterobacteriaceae represents a major concern in hospital setting. Materials & methods: The evolutionary history of carbapenem-resistant Klebsiella pneumonia strains was analyzed by core genome multilocus sequence typing and Bayesian phylogenesis by whole genomes sequencing. Results: A great increase carbapenem-resistant K. pneumoniae causing blood stream infection was observed in the years 2015–2016. At multilocus sequence typing (MLST), they were prevalently ST512 and ST101. ST512 were core genome (cg)MLST 53, while ST101 mainly cgMLST453. The minimum-spanning tree, based on cgMLST, showed strains clustering based on the different STs. By Bayesian phylogenetic analysis, maximum clade credibility tree showed that strains were introduced in the year 2005 with the most probable location in the ICU ward. Two outbreaks by ST101 and ST512 strains with Tower T8 as the probable location were evidenced. Conclusion: Molecular epidemiology is a powerful tool to track the way of transmission of resistant bacteria within the hospital setting.

The rapid diagnosis of carbapenemase-producing (CP) bacteria is essential for the management of therapy and infection control. In this study, RAPIDEC® CARBA NP (RCNP) was evaluated for the rapid screening of CP Enterobacteriaceae, Acinetobacter baumannii complex, and Pseudomonas aeruginosa from clinical specimens collected at five Italian hospitals. Firstly, each site tested 20 well-characterized strains in a blinded fashion. Secondly, each center prospectively tested 25 isolates from blood cultures processed with a rapid workflow (6h after subculture) and 25 isolates from other specimens processed after an overnight culture. The presence of carbapenemases was confirmed by multiplex real-timePCRs targeting carbapenemase genes. RCNP presented an overall sensitivity, specificity, positive predictive value, and negative predictive value of 70%, 94%, 82%, and 89%, respectively, with a higher performance in detection of CP Enterobacteriaceae and a poorer performance in detection of CP A. baumannii complex. With isolates from blood cultures, RCNP could significantly reduce the time required for identification of CP Enterobacteriaceae (less than 9h since the positivization of blood cultures).

Bloodstream infection (BSI) caused by carbapenemase-producing Enterobacteriaceae (CPE) is a major public health concern, particularly in the hospital setting. The rapid detection of resistance patterns is of paramount importance for establishing the proper antibiotic regime. In addition, in countries where CPE are endemic, it is also important to evaluate genetic relationship among the isolates in order to trace pathogen circulation and to improve the infection control programs. This study is an application of a rapid blood culture (BC) workflow consisting of fast reporting of Gram stain results, rapid pathogen identification (using MALDI TOF technology), and a molecular assay for the detection of the major genes conferring resistance, all of them performed directly from positive BCs. The application of phylogenetic and phylodynamic analyses to bacterial whole-genome sequencing (WGS) data have become essential in the epidemiological surveillance of multidrug-resistant nosocomial pathogens. We analyzed 40 strains of Klebsiella pneumoniae subsp. pneumoniae (KP) carrying blaKPC (KP-KPC), randomly selected among 147 CPE identified from BCs collected from consecutive patients from 2013 to 2016. The number of BSIs-related CPE were 23, 31, 43, and 50 in 2013, 2014, 2015, and 2016, respectively. Among 147 CPE isolates, 143 were KP and four were Escherichia coli (EC). The gene blaKPC was detected in 117 strains of KP and in four strains of EC. Other carbapenemase genes, such as blaVIM and blaOXA-48, were detected in four and nine different isolates of KP, respectively. Moreover, 13 KP strains carried two resistance genes: twelve vehicled blaKPC plus blaVIM and one blaKPC plus blaOXA-48. Phylogenetic analysis of bacterial WGS data was used to investigate the evolution and spatial dispersion of KP in support of hospital infection control. The maximum likelihood tree showed two main clades statistically supported, with statistical support for several subclusters within as well. The minimum spanning tree showed mixing between sequences from different years and wards with only few specific groups. Bayesian analyses are ongoing, as the aid of Bayesian genomic epidemiology in combination with active microbial surveillance is highly informative regarding the development of effective infection prevention in healthcare settings or constant strain reintroduction.