Il fenomeno dell’antibiotico resistenza nelle patologie ad eziologia infettiva. La gestione del paziente critico

Inglese

Antimicrobial resistance (AMR) is one of the most relevant threats to global public health, with negative consequences in morbidity and mortality of infections caused by AMR bacteria. Understanding the mechanisms of AMR is key for the adoption of preventive strategies and the management of patients. This study describes the rapid nosocomial spread of K. pneumoniae ST512 (endemic in Italy), characterized by the co-production of class A and D carbapenemases. Clinical records analysis revealed that Intensive Care Unit admission is a risk factor for the development of Hospital Acquired Infections (HAIs). After novel antibiotic therapies (ceftazidime/avibactam, meropenem/vaborbactam, imipenem/relebactam) became available, concerns about the emergence of resistant strains were expressed, thus it is crucial to identify possible resistance patterns among strains. The comparison between phenotypic and genotypic profile of K. pneumoniae strains cause of HAIs gave useful information to guide therapeutic choices. Although preliminary, the data highlighted differences (p-value<0.0001) of the phenotypic profiles when considering the expression of different carbapenemases. This is consistent with Antimicrobial Resistance Index (ARI) values calculated for the strains included in the study, demonstrating the effectiveness of ARI for the comparison of strains based on AMR profile. Whole Genome Sequencing (WGS) analysis showed the presence of more than 20 AMR genes, including carbapenemase encoding genes blaKPC-3, blaKPC-31 and blaOXA-181.Plasmid location allows their spread, contributing to selection and diffusion of AMR bacteria, as seen with phenotypic analysis. WGS implementation could provide an important tool to contrast AMR and provide tailored therapies in case of HAIs. Moreover, the adoption of rapid antimicrobial susceptibility test, based on the genotypic profile of strains can be useful to guide therapeutic choices, mainly for the management of critically ill patients