Abstract Background: Seasonal variation in bacterial epidemiology and antimicrobial resistance (AMR) has been reported across healthcare settings. We evaluated seasonal variation in community-onset bacterial detection and AMR in a multicenter healthcare system. Methods: We conducted a retrospective cohort study of clinical cultures obtained on hospital days 0–2 across 4 hospitals from 2012 to 2016. Six bacterial organisms were evaluated. Summer was defined as July–August and winter as January–February. Multivariable logistic regression evaluated associations between season and organism detection, specimen source, and AMR, adjusting for age, admission source, diabetes mellitus, chronic dermatitis, and wounds. Results: Among 95,964 community-onset clinical cultures from 48,133 patients, 2,820 (2.9%) yielded a study-target organism. In unadjusted analyses, summer was associated with increased odds of Klebsiella pneumoniae (odds ratio (OR), 1.51; 95% confidence interval (CI), 1.31–1.73) and Pseudomonas aeruginosa detection (OR, 1.30; 95% CI, 1.10–1.54). Acinetobacter baumannii demonstrated a similar but statistically uncertain pattern (OR, 1.74; 95% CI, 0.99–3.05). Season was not associated with overall target-organism detection after adjustment (adjusted odds ratio (aOR), 0.96; 95% CI, 0.88–1.04; P = .28). Resistant/intermediate isolates accounted for 386 of 1,531 (25.2%) summer and 331 of 1,289 (25.7%) winter isolates. Season was not associated with overall AMR after adjustment (aOR, 1.07; 95% CI, 0.89–1.28; P = .47). Conclusions: Seasonal differences occurred in unadjusted detection of selected gram-negative organisms, but season was not associated with overall target-organism detection or AMR after adjustment. These findings support interpreting seasonal microbiologic surveillance in the context of local epidemiology and patient and healthcare-related characteristics.
Abstract Background: Fungal blood cultures (fungal-isolator cultures) (FBCs) require extended incubation (4–6 wk) and substantial laboratory resources. However, their diagnostic yield is limited in solid organ transplant (SOT) recipients. Understanding the utilization patterns and yield of FBCs in SOT recipients is essential to inform diagnostic stewardship. Methods: A retrospective, single-center study was conducted at Duke University Hospital (July 2021–January 2025) evaluating all FBCs collected from adult SOT recipients. Demographics, clinical indications, culture results, antifungal use, infectious diseases (ID) involvement, and outcomes were extracted from electronic medical records (EMRs). Results: A total of 137 FBCs from 104 SOT recipients were analyzed. The cohort demonstrated high acuity, with a median hospitalization of 32 days and a 23% 6-month mortality. Heart transplant recipients accounted for the largest proportion (37%) of FBCs, as well as the largest proportion (46%) of inappropriate FBCs. Only 1 of 137 cultures (0.7%) yielded a fungal organism (Histoplasma capsulatum); 5 grew bacterial organisms. Two-thirds of cultures were collected, although patients were already receiving antifungals. ID was consulted in 91% of cases, but recommended FBC collection in only 42%. Sixty-nine percent of cultures were collected without a suspected fungal pathogen documented in the chart. Conclusions: FBCs had an extremely low yield (0.7%) in SOT recipients with the sole positive isolate being a dimorphic fungus. Most cultures were collected without a targeted fungal pathogen and without ID recommendation, representing an opportunity for diagnostic stewardship interventions to reduce unnecessary utilization and associated laboratory burden and cost.
Abstract The Veterans Health Administration was an early adopter of antimicrobial stewardship, with dedicated programs required since 2014. Here we describe how antimicrobial stewardship at the Minneapolis VA Health Care System (MVAHCS) has grown from this requirement and the emergence of diagnostic stewardship, which aims to modify the ordering and reporting of diagnostic tests to improve treatment. We describe examples where diagnostic stewardship has been implemented and how it fits into the overall goal of antimicrobial stewardship: coordinated interventions to optimize antimicrobial treatment.
Abstract Background: Some clinical documentations, including surgical antibiotic administration data and hand-written notes, are only captured in non-digitized scanned documents, limiting their accessibility. Commercially available artificial intelligence (AI) tools may offer a means of extracting such data from scanned-in images, however, little is known about their accuracy for this application. Thus, the objective of this study was to evaluate the performance of two commercially available, protected AI tools for extracting antibiotic administration data as part of a larger study evaluating the sustainability of stewardship goals achieved during the Surgical Care Improvement Project mandatory reporting period. Methods: A sample of surgical cases with antibiotic administration data documented only in non-digitized scanned records was manually reviewed and submitted to two commercially available AI tools (Claude Sonnet version 4.6 and OpenAI version 5.0). The AI tools were prompted to extract data about antibiotic name, dose, and administration time. Results: The total accuracy across all three metrics (drug, dose, timing of administration) was limited (3/14, 21.4% for Claude and 2/14, 14.3% for OpenAI), but overall excellent for identifying that an antibiotic had been administered and the type of drug administered (Claude, 100%, OpenAI, 92.8%). AI tools struggled to identify total dose administered (Claude, 50%, OpenAI, 42.9%), primarily due to challenges distinguishing aliquots from administered doses. Accuracy for identifying timing was also variable, particularly when administration time was documented using a graphic scale rather than written text. Conclusions: Potential utility of these commercial tools for extracting antimicrobial use data from scanned-in records depends upon review goals and what level of precision is necessary.
Abstract Before Taiwan’s national outpatient parenteral antimicrobial therapy (OPAT) reimbursement, we retrospectively evaluated 241 OPAT episodes among 173 patients at a cancer hospital. Median parenteral therapy duration was 7 days, with 73.0% clinical improvement and 24.9% unplanned admission. Modeled costs estimated savings of approximately US$137 per OPAT case when treatment days replaced hospitalization.
