Ralstonia species are environmental Gram-negative bacilli increasingly linked to healthcare-associated bloodstream infection (BSI) outbreaks from contaminated medical solutions. We describe an outbreak of Ralstonia mannitolilytica BSI in which the source was identified and withdrawn within 24 hours.

Following an unusual cluster of R. mannitolilytica blood cultures on 29 September 2024 at a 700-bed tertiary-care hospital in Oman, we conducted a multidisciplinary investigation including chart review, hospitalwide surveillance, environmental and product sampling, antimicrobial susceptibility testing, and pulsed-field gel electrophoresis (PFGE) of clinical and product isolates.

Between 29 September and 8 October 2024, 21 patients met the case definition (median age 9 yr; 62% pediatric; 62% male; 95% immunocompromised; 86% with central venous access). Newly introduced pre-filled 10 mL 0.9% sodium chloride vials from a single manufacturer yielded R. mannitolilytica with concordant clinical and product antimicrobial susceptibility profiles. PFGE of 18 clinical isolates and one product isolate demonstrated 100% genetic relatedness, confirming a single-clone outbreak. The implicated product was withdrawn within 24 hours of cluster recognition. Thirteen of 21 patients had their central catheters removed; all received intravenous trimethoprim–sulfamethoxazole. Two patients experienced bacteremia recurrence after initial line retention; no outbreak-related deaths occurred.

Prefilled saline vials can serve as the source of clonal R. mannitolilytica BSI outbreaks in immunocompromised patients. Laboratory-driven cluster detection, multidisciplinary coordination, and rapid product suspension enabled source identification within 24 hours and limited outbreak size and severity. Vigilance after introduction of new pharmaceutical products and prompt catheter removal in catheter-associated Ralstonia BSI are essential.

We evaluated usability of a web-based clinical decision support tool designed to support antibiotic stewardship by helping clinicians differentiate asymptomatic bacteriuria from true urinary tract infections.

Mixed methods usability evaluation with qualitative think-aloud sessions and survey.

Private academic medical center.

Clinicians who evaluate and treat older adults with suspected asymptomatic bacteriuria or urinary tract infections.

Participants used the tool to assess three standardized clinical scenarios, verbalizing their thoughts as they used the tool, followed by a short debrief interview and survey. Transcripts of audio recordings were analyzed using qualitative content analysis across four usability domains: navigation, content, functionality, and layout.

Seven clinicians (four attending physicians, three advanced practice providers) practicing in primary care, outpatient, and inpatient settings participated. The mean System Usability Score was 85.4 (SD = 10.5; range 75–100), indicating “excellent” usability. Three qualitative themes emerged: (1) positive responses to the tool’s speed, simple entry, and reassuring guidance; (2) content-related challenges, including missing symptoms, unclear fever thresholds, undefined terminology, and absent caveats for allergies, resistant organisms, or unique populations; and (3) suggested navigational changes, including links opening in new tabs, preserving entered clinical data, and reorganizing the symptom checklist. Participants highlighted electronic health record integration as necessary for sustained use.

Participants found the tool usable and clinically valuable, particularly when infectious disease expertise is limited. Targeted refinements will be addressed before testing in a randomized study with a larger more representative sample. Future work will also pursue electronic health record integration via an embedded hyperlink for broader deployment.

Antimicrobial stewardship programs (ASPs) are crucial in reducing healthcare-associated infections caused by multidrug-resistant organisms (MDROs). Integrating rule-based decision support systems into ASPs may enhance antimicrobial prescribing practices.

This retrospective study evaluated the implementation of a rule-based decision support “Smart ASP” at Queen Mary Hospital in Hong Kong. Changes in antimicrobial consumption [defined daily dose (DDD) per 1,000 patient days] were assessed using interrupted time series (ITS) analysis. Time-lag dynamics between broad-spectrum antimicrobial use and MDRO incidence, including carbapenem-resistant Acinetobacter (CRA) and carbapenemase-producing Enterobacterales (CPE), were examined using double-prewhitened cross-correlation function (CCF) following autoregressive integrated moving average (ARIMA) modeling.

From 2016 to 2025, median targeted antimicrobial consumption was 188 DDD per 1,000 patient days (IQR, 169–204). Smart ASP implementation was associated with a significant immediate reduction in overall antimicrobial use by 27 DDD per 1,000 patient days (P = .012). The subsequent long-term consumption trend remained unchanged, reflecting appropriate broad-spectrum use in response to rising MDRO incidence. Increased piperacillin-tazobactam use was ecologically associated with higher CPE incidence one month later (Lag +1: CCF = +0.211, P = .022). Conversely, rising CPE incidence was associated with subsequent reduced imipenem-cilastatin use the following month (Lag −1: CCF = −0.182, P = .047). Overall CPE incidence exhibited a marked upward trend.

The rule-based Smart ASP was associated with a significant but transient reduction in antimicrobial consumption, demonstrating the need for continuous evaluation. Advanced statistical approaches, particularly ARIMA modeling, improved understanding of ecological, time-lagged associations between antimicrobial use and resistance, informing future stewardship strategies.

Management of shigellosis is increasingly complicated by antimicrobial resistance, yet susceptibility testing is rarely performed, and the role of broad-spectrum empiric therapy in hospitalized adults remains unclear.

We conducted a multi-center retrospective cohort study of adults hospitalized with stool-confirmed Shigella spp. from October 2023 to August 2024 across five hospitals in the Portland metropolitan area. The primary outcome was time from antibiotic initiation to symptom resolution (less than 3 stools in 24 h) and the secondary outcome was length of hospital stay.

Of 45 patients included in the outcome analyses, 29 (64%) received carbapenems and 16 (36%) received non-carbapenem antibiotics. Median time from antibiotic initiation to symptom resolution was 18 hours (IQR 9–37) in the carbapenem group and 29 hours (IQR 15–36) in the non-carbapenem group, with no significant difference between groups (P = .89). The median length of hospital stay was significantly longer in the carbapenem group, at 5.4 days (IQR 3.6–8.3), compared with 3.9 days (IQR 2.6–4.4) in the non-carbapenem group (P = .02). Only 26% of patients had susceptibility testing ordered.

Carbapenem use was not associated with faster symptom resolution and was associated with significantly longer hospitalization. Susceptibility testing was underutilized and may be essential to guide local empiric and targeted therapy decisions.

Carbapenem-resistant Enterobacterales (CRE) infections carry high mortality and limited treatment options. We evaluated outcomes among adults with CRE infections at Ministry of National Guard-Health Affairs facilities in Saudi Arabia, comparing monotherapy with combination therapy.

This multicenter retrospective cohort study included adults (≥18 years) with CRE infections during 2020–2024 at King Abdulaziz Medical City (Jeddah and Riyadh). CRE was defined phenotypically per CLSI criteria (first isolate per patient). Bivariate analyses, multivariate logistic regression, and Kaplan–Meier survival analysis compared monotherapy and combination therapy.

Among 224 patients (median age 70 years; 62.5% male), overall mortality was 43.3%, and Klebsiella pneumoniae accounted for 96.0% of isolates. Combination therapy was associated with higher mortality than monotherapy (44.5% vs. 26.7%; P = .047) and remained independently associated with mortality after adjustment for age, gender, and comorbidities (adjusted OR = 2.28, 95% CI: 1.08–4.83; P = .032). A significant treatment–mortality difference was seen in patients without solid tumors (P = .031) but not in those with solid tumors (P = 1.000). Respiratory and blood infections carried the highest mortality (58.3% and 55.3%).

CRE infections carry a high mortality burden among adults in Saudi Arabia. The higher mortality with combination therapy may, in part, reflect confounding by indication, with broader-spectrum regimens prescribed for sicker patients whose severity was not captured. Prospective studies with disease-severity scoring and individualized treatment are needed, particularly for immunocompromised patients.

To investigate the factors associated with mortality and the outcomes of an antimicrobial stewardship program (ASP) in pediatric patients with sepsis.

Retrospective cohort study.

A tertiary care teaching hospital in Thailand.

Pediatric patients with sepsis.

This study reviewed electronic medical records of pediatric patients. A computer-generated random sequence was used to select 240 patients who met the inclusion criteria for the analysis.

Between January 1, 2021, and December 31, 2024, a total of 1,777 patients were enrolled in the ASP. Of 240 eligible patients, males accounted for 56.7% of the cohort, with a median age of 1.0 year (interquartile range 0–6). Positive blood cultures were identified in 72 patients (30.0%). ASP interventions identified antibiotic-related problems in 93 patients (38.8%), with primary physicians adhering to ASP recommendations in 55 cases (59.1%). Septic shock was the only factor significantly associated with 30-day mortality (adjusted odds ratio 4.064; 95% confident interval: CI 1.265–13.061; P = .019). Mortality rates were not different between groups regarding ASP compliance or blood culture results. The day of therapy/1,000 PD for vancomycin and meropenem were significantly lower in the compliance group compared to the non-compliance group (81.9 vs 135.4, P = .026; and 169.9 vs 260.3, P = .012, respectively).

Septic shock was the only factor associated with 30-day mortality. ASP help detected antibiotic-related problems and reduced meropenem and vancomycin consumption in pediatric patients with sepsis.

This systematic review aims to describe the impact of specific antimicrobial stewardship program (ASP) strategies on implementation and stewardship-related outcomes.

Systematic literature review.

We systematically searched multiple databases using search terms that focused on stewardship and implementation. An original search was completed on October 29, 2021, and then updated on February 26, 2025. Studies were eligible for inclusion if they were in English, reported an antimicrobial resource outcome, and using either a comparison group or a pre/post design as a minimum level of rigor. Data from articles were extracted to understand the context and design of the evaluation, the types of approaches used, and outcomes assessed.

Out of 2035 studies that were identified, we included 250 full-text peer-reviewed manuscripts. Of the 250 studies included, 52% were conducted in the USA. The majority (80%) of studies were conducted in inpatient settings, particularly in adult academic hospitals (29%). Programs were often implemented hospital-wide or across multiple specialties, with a focus on emergency medicine and intensive care units. Education or learning (64% of studies) and handshake stewardship (56% of studies) were by far the most common ASP strategies used. Mortality (36% of studies) and drug choice (57% of studies) were the most tracked patient and resource outcomes, respectively.

Our review highlights the variability in approaches as part of ASPs, indicating a need for a more systematic understanding of how different approaches are implemented and their subsequent impact on antimicrobial use.

This study evaluated differences in total cost of care (TCC) and length of stay (LOS) among patients with potentially preventable catheter-related infections (PPCRIs).

A retrospective cohort analysis was conducted using the Premier Healthcare Database for calendar years 2022 and 2023. PPCRI cases and at-risk non-PPCRI cases were identified using the Solventum Potentially Preventable Complications (PPC) v38 grouper methodology, which identifies complications occurring during inpatient stays while applying clinical exclusions to avoid capturing progression of preexisting conditions. Each PPCRI case was matched to an at-risk non-PPCRI case based on age, race, sex, diagnosis-related group, and severity of illness.

PPCRI cases experienced significantly higher TCC and LOS in both study years. Mean TCC for PPCRI cases was approximately $162,000 in 2022 and $187,000 in 2023, compared with $44,000 and $40,000 for non-PPCRI cases, respectively (P < .0001). Average excess LOS was 38 days in 2022 and 44 days in 2023 for PPCRI cases, versus 6 and 5 days for non-PPCRI cases (P < .0001). LOS exceeded expected values in 97% of PPCRI cases compared with 63% of non-PPCRI cases in both years. Mortality was significantly higher among PPCRI cases (17% vs 6% in 2022; 12% vs 2% in 2023; P < .0001). Discharge to home occurred more frequently in non-PPCRI cases (48% vs 21% in 2022; 52% vs 23% in 2023; P < .0001).

PPCRIs are associated with substantial excess LOS, which drives markedly higher TCC. Targeted prevention of PPCRIs could yield savings of approximately $100,000 per case.

To evaluate the impact of the HemoAlert program—a notification system providing pathogen identification and antimicrobial susceptibility results—on the time to initiation of appropriate antimicrobial therapy in patients with bacteremia.

Pre–post-quasi-experimental study.

Siriraj Hospital, the largest tertiary care hospital in Bangkok, Thailand.

Adult hospitalized patients with at least one positive blood culture between December 2021–February 2022.

A quasi-experimental study was conducted to assess the impact of the HemoAlert program, which delivered SMS notifications of final microbiology results to the responsible physician and updated the patient’s medical record. The primary outcome was the time to appropriate antimicrobial therapy. Secondary outcomes included appropriateness of antimicrobial therapy at 72 and 120 hours, favorable clinical outcome, 28-day mortality, and length of hospital stay.

A total of 150 patients were included in both periods. Demographics and pathogen distribution were similar between groups. The most common pathogens were Escherichia coli, followed by Klebsiella pneumoniae, and Staphylococcus aureus. The postimplementation group also showed a trend toward a shorter time to appropriate antimicrobial therapy (81.38 ± 61.38 vs 66.17 ± 51.81 h; P = .08). Patients in the postimplementation group were more likely to receive appropriate therapy within the first 72 hours (34.0% vs 22.7%; P = .03). Favorable clinical response was more frequent after implementation (74.0% vs 85.3%; P = .02), whereas 28-day mortality was similar (24.0% vs 18.0%; P = .20).

The HemoAlert program improved the timeliness and appropriateness of antimicrobial therapy and enhanced clinical response in patients with bacteremia, supporting the utility of simple notification systems in optimizing management.

Antimicrobial resistance (AMR) is a global public health concern. In Japan, outpatient dental practice frequently involves antimicrobial prescriptions, with oral third-generation cephalosporins prescribed more often than the guideline-recommended amoxicillin. We examined the association between dentists’ multidimensional AMR-related attitudes and selection of oral third-generation cephalosporins.

Cross-sectional secondary analysis of a questionnaire survey.

The questionnaire survey was administered to 406 dentists affiliated with the Kagawa Dental Association (November 2024–January 2025), and 111 responses were analyzed (response rate, 27.3%).

The primary outcome was self-reported selection of oral third-generation cephalosporins. AMR attitudes were quantified as overall and domain-specific scores for sense of crisis, self-efficacy, and role awareness. Multivariable logistic regression analysis was performed, adjusting for years of clinical experience, sex, post-treatment prophylactic antimicrobial use, and practice type (in-house vs. external pharmacy dispensing). Domain-specific scores were analyzed separately to avoid multicollinearity.

High overall AMR attitude scores were associated with a low likelihood of selecting third-generation cephalosporins (odds ratio [OR], 0.82; 95% confidence interval [CI], 0.72–0.92). Self-efficacy (OR, 0.50; 95% CI, 0.34–0.73) and role awareness (OR, 0.59; 95% CI, 0.42–0.84) showed strong negative associations. Post-I treatment prophylactic antimicrobial use and practice type involving external pharmacy dispensing were positively (OR, 2.69; 95% CI, 1.07–6.75) and negatively (OR, 0.34; 95% CI, 0.15–0.77) associated with selection of third-generation cephalosporins, respectively.

Dentists’ AMR-related attitudes, particularly self-efficacy and professional role awareness, were strongly associated with antimicrobial prescription choices. Interventions targeting these factors may promote appropriate antimicrobial use in dental practice.

To evaluate the clinical impact of the BioFire® FilmArray® Pneumonia Panel (BFPP) in sputum specimens from non-intensive care unit (ICU) patients with suspected lower respiratory tract infection.

Retrospective cohort study.

1400-bed tertiary referral academic medical center.

Patients who had a sputum specimen with BFPP and standard of care (SOC) culture between 9/1/2022 and 8/31/2024 while on a non-ICU floor were included. An antibiotic change evaluation of actual versus theoretically possible therapy changes was completed at two time points, after BFPP results and after SOC results, overall and by various characteristics, in addition to an assessment of the appropriateness of antibiotic regimens.

189 specimens were included. 48.7% of theoretical changes were acted upon based on BFPP results compared to 87.8% of theoretical changes acted upon based on SOC results. Actual compared to theoretical de-escalation of gram-positive agents occurred more frequently compared to gram-negative agents post-BFPP (43.1% vs 32%) and post-SOC (60.5% vs 38.7%). De-escalation was more frequent in non-neutropenic patients compared to neutropenic patients (39.5% vs 26.1% post-BFPP; 54.7% vs 21.1% post-SOC) and in medicine floor patients compared to oncology floor patients (52.5% vs 23.8% post-BFPP; 72.5% vs 30.2% post-SOC). Appropriateness of antibiotic regimens was higher post-SOC results (77.8%) compared to post-BFPP results (66.1%).

Higher rates of theoretical antibiotic changes were acted upon post-SOC results compared to post-BFPP results, suggesting a disconnect between BFPP results and provider action. Further research is needed to assess factors associated with actionability of the BFPP.