Professor Maurizio Sanguinetti
In recent years, antimicrobial resistance (AMR) has reached proportions of such significance to propel national and global health authorities to regard AMR as today’s “serious threat” worldwide.
Targeting AMR has important clinical implications not only related to diagnosis and management1 but also prevention of infectious diseases2, particularly those causing sepsis3.
Determinants of deaths associated with antimicrobial-resistant pathogens known as causative agents of community and hospital-acquired bloodstream infections (BSIs) remain not fully explained4. However, in a meta-analysis of sepsis treatment, the mortality rate in patients who were receiving inappropriate antibiotic therapy was higher than among patients who were appropriately treated6.
Innovations in diagnostics
Infectious diseases diagnostic innovations7 are broadening the capability for rapid identification and characterisation of BSI pathogens, defining the makeup of antimicrobial-resistant organisms in order to ensure maximal impact at the patient level8.
This is particularly true for Gram-negative bacteria (e.g. Enterobacteriaceae), which cause difficult-to-treat infections in immunosuppressed and hospitalised patients, because of multiple resistance mechanisms contributing to each observed phenotype in antibiotic-resistant isolates. In some settings, clinicians are routinely obliged to treat patients with broad-spectrum antibiotics – even when bacterial infection is microbiologically absent1 – thereby implying the emergence of antibiotic-resistant bacterial organisms.
The role of precision medicine
We agree that the new “precision medicine” paradigm – which has extensively been used in cancer chemotherapy – should be ever increasingly applied to antimicrobial chemotherapy1.
In this context, it is worth noting that T2Resistance™ panel has recently been marketed as a nonculture diagnostic test that uses T2 magnetic resonance to detect encoding genes in whole blood samples (https://www.t2biosystems.com/products-technology/pipeline/t2resistance-panel/). The information available from rapid diagnostic testing can be immediately incorporated into clinical decision-making regarding the therapy of Gram-negative bacterial BSIs. Specifically, algorithms for the interpretation of AMR testing and treatment of BSIs may be adopted to achieve a rapid, effective and “molecularly-targeted” antimicrobial chemotherapy regime for any individual patient.
In conclusion, use of rapid diagnostic approaches for AMR detection will likely provide an important means for achieving the balance between administration of new and existing antibiotics and emergence of antimicrobial-resistant BSI pathogens. Studies that measure the impact of rapid diagnostics-based interventions on both antimicrobial utilisation and time to effective treatment, as well as that determine if use of rapid diagnostics improves BSI patients’ outcomes are needed.