Antimicrobial Resistance and Risk-Stratified Empiric Therapy in Community-Onset Sepsis

Presenter: Winnie Lee

This retrospective study evaluated empiric antimicrobial prescribing patterns and outcomes in community-onset sepsis across a large UK hospital network.

A total of 3,338 patients met sepsis criteria. Overall, 30-day mortality was 11.1%, increasing with higher National Early Warning Score 2 (NEWS2) scores (p<0.05). Extended spectrum β-lactamase-producing pathogens (ESBL) accounted for 7% of cases.

Empiric therapy patterns:

Ceftriaxone was the most commonly used empiric antibiotic (12.5%). Dual therapy was frequent, most commonly amikacin + ceftriaxone in both ESBL (20.6%) and non-ESBL (30.6%) infections. Antibiotic regimens were frequently modified within 48 hours, with 17.9% of patients undergoing escalation in WHO AWaRe category within 24 hours.

ESBL subgroup:

30-day mortality was 12.1%, with no significant difference compared to non-ESBL patients. Ceftriaxone remained the most common empiric agent (15.8%), while meropenem use was 5.1% higher than in non-ESBL cases. AWaRe escalation within 24 hours occurred in 21.6% of ESBL-positive patients.

Overall, empiric prescribing was variable, with frequent early escalation and adjustments in therapy.

Modeling A Point-Of-Care Diagnostic Panel Implementation for Rapid Bloodstream Infection Identification in Remote Settings: A Cost-Effectiveness Analysis

Presenter: Kristian Bagge

This retrospective study evaluated the potential impact of implementing a rapid molecular diagnostic panel (QIAstat-Dx® BCID Plus AMR) for blood culture analysis in a remote hospital setting.

A total of 46,546 blood cultures from 6,119 patients (2020–2024) were analysed, with 2,392 positive bottles from 851 patients, representing 996 bacteremic events. The mean workflow times were: sampling to positivity 18.6 hours, positivity to microscopy 6.8 hours, and microscopy to MALDI-TOF 11.2 hours, resulting in a total delay of ~18 hours post-positivity.

The rapid panel would have detected 79.9% (796/996) of initial bacteremic events. Among follow-up samples (day 2–30), 95.2% (20/21) of discrepant Gram stain cases and 86.7% (78/90) of consistent cases were detectable, although only 4/78 represented new findings.

Implementation of the rapid test could reduce identification time by at least 10 hours. The incremental cost-effectiveness ratio (ICER) was €124.6 per sample achieving rapid identification. Overall, rapid molecular testing demonstrated high detection rates with reduced turnaround time in a remote setting.

Rapid Pathogen and Antimicrobial Resistance Detection in Bloodstream Infections Using Short Subculture and Nanopore Sequencing

Presenter: Mariana Pitombeira Liborio

This experimental study evaluated early pathogen identification and resistance detection in bloodstream infections (BSIs) using short incubation and Oxford Nanopore sequencing. Blood samples spiked with CTX-M-15-producing E. coli (EC958) (<50 CFU/mL) were incubated and analysed hourly up to 7 hours. Two extraction methods were compared: MolYsis + DNeasy (B5+D) and MolYsis + BiOstic (B5+B).

Bacterial growth increased with time, reaching 10² CFU/mL at 3 hours and 10⁶ CFU/mL at 7 hours. With increasing incubation, cycle threshold values decreased for both methods, indicating higher bacterial load.

Using the B5+B method, E. coli was detected within 5 minutes of sequencing at 5 hours incubation (~10⁴ CFU/mL), and the resistance gene CTX-M-15 was identified in just over 3 hours of sequencing at 7 hours (~10⁶ CFU/mL). In contrast, the B5+D method did not detect the organism within the first hour of sequencing for any sample. Overall, rapid detection of pathogen and resistance markers was achievable within hours using optimized extraction and sequencing workflows.

ESCMID 2026, 17-21 April, Munich, Germany.