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Treatment assessment and patient outcome for sepsis depend predominantly on the timely administration of appropriate antibiotics 1-3 . However, the clinical protocols used to stratify and select patient-specific optimal therapy are extremely slow 4 . In particular, the major hurdle in performing rapid antimicrobial susceptibility testing (AST) remains in the lengthy blood culture procedure, which has long been considered unavoidable due to the limited number of pathogens present in the patient's blood. Here we describe an ultra-rapid AST method that bypasses the need for traditional blood culture, thereby demonstrating potential to reduce the turnaround time of reporting drug susceptibility profiles by more than 40-60 h compared with hospital AST workflows. Introducing a synthetic beta-2-glycoprotein I peptide, a broad range of microbial pathogens are selectively recovered from whole blood, subjected to species identification or instantly proliferated and phenotypically evaluated for various drug conditions using a low-inoculum AST chip. The platform was clinically evaluated by the enrolment of 190 hospitalized patients suspected of having infection, achieving 100% match in species identification. Among the eight positive cases, six clinical isolates were retrospectively tested for AST showing an overall categorical agreement of 94.90% with an average theoretical turnaround time of 13 ± 2.53 h starting from initial blood processing., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

Accelerate Pheno™ (ACC) is a fully automated system providing rapid identification of a panel of bacteria and yeasts, and antimicrobial susceptibility testing of common bacterial pathogens responsible for bloodstream infections and sepsis. Diagnostic accuracy for identification ranges from 87.9 to 100%, and antimicrobial susceptibility testing categorical agreement is higher than 91%. The present review includes peer-reviewed studies on ACC published to date. Both interventional and hypothetical studies evidenced the potential positive clinical role of ACC in the management and therapy of patients with bloodstream infections and sepsis, due to the important reduction in time to report, suggesting a crucial impact on the therapeutic management of these patients, provided the presence of a hospital antimicrobial stewardship program, a 24/7 laboratory operating time and a strict collaboration between clinical microbiologist and clinician. Further prospective multicenter studies are necessary to explore the impact of this system on mortality, length of stay and spread of multidrug-resistant organisms.

The diagnosis of bloodstream infection requires the optimum combination of media in an automated blood culture system for maximum recovery of pathogens with the earliest time to detection. In a previous work, we showed that for patients admitted to the Emergency Department of our hospital, the combination of BACTEC lytic anaerobic and BACTEC aerobic vials was more efficient than BACTEC anaerobic and BACTEC aerobic vial. In this study, we extended the work including a broader patient population, representative of all hospital. A total of 8629 cultures were collected during the pre-lytic phase, from 01 July 2013 to 30 June 2014 and 7940 cultures during the post-lytic phase, ranged from 01 July 2015 to 30 June 2016. The number of positive blood cultures was higher during the post-lytic phase (19.74%) than in the pre-lytic phase (17.52%), particularly for Escherichia coli, Staphylococcus spp., Enterococcus spp., and anaerobes. We also observed a significant decreased of the time to detection, with the mean and median in the post-lytic phase of 17.68 and 13.05 h compared with 19.49 and 14.47 h in the pre-lytic phase. Whereas the time to detection was the same for organisms recovered in the aerobic Plus bottles for both time periods, time to detection for the anaerobic lytic bottles was significantly faster than with the anaerobic Plus bottles. This study carried out on a long time observation reported that a simple modification of composition of blood culture set could lead to better results in bloodstream infection detection.

Background: Advances in medicine have improved our understanding of sepsis, but it remains a major cause of morbidity and mortality. The detection of pathogens that cause sepsis remains a challenge for clinical microbiology laboratories., Content: Routine blood cultures are time-consuming and are negative in a large proportion of cases, leading to excessive use of broad-spectrum antimicrobials. Molecular testing direct from patient blood without the need for incubation has the potential to fill the gaps in our diagnostic armament and complement blood cultures to provide results in a timely manner. Currently available platforms show promise but have yet to definitively address gaps in sensitivity and specificity., Summary: Significant strides have been made in the detection of pathogens directly from blood. A number of hurdles, however, remain before this technology can be adapted for routine use., (© 2018 American Association for Clinical Chemistry.)