bluuebunny/crossref_metadata_2025_split huggingface dataset:
175. Concordance of UTI Antibiotic Treatments with Facility-Specific Antibiograms in Nursing Homes
Authors: Langenstroer Madeline C , Jolles Sally , Crnich Christopher J , Jump Robin , Wilson Brigid , Bej Taissa A , Kowal Corinne , Hicks Oteshia , Taylor Lindsay , Multhauf Grace , Furuno Jon P , Santos Evita T , Shilling Hailey , Zhou Michelle H , Nace David A , Murillo Theresa N , Mangal Krishnendu 
Published: January 2025

Abstract

Background
Empiric antibiotic treatment of urinary tract infections (UTI) in nursing homes (NHs) is complicated by increasing antibiotic resistance. Antibiograms may enhance empiric antibiotic treatment decisions in this setting. We conducted a pilot study of a urine-specific antibiogram in 9 NHs in Oregon and Pennsylvania. The objectives of this study were to (1) characterize patterns of antibiotic resistance among uropathogens recovered from study NHs and (2) determine the concordance between antibiotic prescriptions and facility-specific antibiograms.Table 1.WISCA-Concordant Antibiotics across 9 NHs

Methods
We developed a facility-specific weighted incidence syndromic cumulative antibiogram (WISCA) using two years of urine culture results for each study NH. The WISCA conveyed the cumulative susceptibility of facility-collected uropathogens to 7 antibiotics in three susceptibility strata ( &gt;90%, 80-89%, and &lt; 80%). Data on antibiotic prescriptions for the empiric treatment of UTI during the 6-month pilot were abstracted from facility health records and entered into a REDCap database. Antibiotic prescriptions with a probability of activity exceeding the 80% susceptibility threshold were classified as WISCA-concordant.Figure 1.Concordance of Empiric Antibiotic Selection with Facility-Specific WISCAs

Results
WISCA susceptibility patterns varied considerably across NHs and regions (Table 1). On average, two oral antibiotic options with projected activity exceeding 80% were available in most Oregon NHs. In contrast, oral antibiotic options with activity exceeding 80% were uncommon in Pennsylvania NHs. Ceftriaxone and Ciprofloxacin were the only antibiotics with activity in these facilities. There were 173 empiric antibiotic treatments for UTI in study NHs during the pilot. A minority of the antibiotics chosen were concordant with the facility-specific WISCA (n = 69, 39.9%), although this varied by facility (Figure 1).

Conclusion
Our study demonstrates wide variability in antibiotic susceptibility of uropathogens at both the facility and regional levels. Antibiotics selected for the empiric treatment of UTI in study NHs were projected to have limited activity based on facility-specific WISCAs. Further studies to examine the factors influencing antibiotic choice and level of concordance with patient-specific culture results are ongoing.

Disclosures
Robin Jump, MD, PhD, Abacus: Grant/Research Support|Merck: Grant/Research Support|Pfizer: Advisor/Consultant|Pfizer: Grant/Research Support Jon P. Furuno, PhD, Merck & Co., Inc: Grant/Research Support
176. A Quality Improvement Endeavor to Improve Antibiotic Prescribing for Children with Acute Otitis Media in Emergency and Urgent Care Settings
Authors: Dimo Joana , Weber Matthew J , Birkholz Meghan C , Topoz Irina , Poole Nicole M 
Published: January 2025

Abstract

Background
Acute otitis media (AOM) self-resolves without antibiotics in 60-75% of cases. This study evaluates the impact of a quality improvement intervention on antibiotic prescribing for pediatric AOM.Figure 1.Proportion of antibiotics prescribed per all AOM diagnoses in patients 61 days to 18 years old.

Methods
A bundled intervention for AOM included (1) an electronic health record (EHR) order set that preselected a 5-day antibiotic duration for children 24 months and older (April 2021) and (2) creation of a local clinical care pathway (CCP) for AOM (December 2022). The CCP encouraged observation and pain management in children 24 months and older, as well as children 6-23 months with unilateral, non-severe AOM. A retrospective review of patients 61 days to 18 years old presenting to emergency and urgent care centers between January 2019 through September 2023 was conducted. Outcomes were (1) rates of antibiotic prescribing (enteral or ceftriaxone) in patients 61 days to 18 years old, (2) treatment duration of 5 or fewer days (excluding azithromycin) in patients 24 months to 18 years old, and (3) first-line antibiotic choice (amoxicillin) in patients 61 days to 18 years old. Statistical process control charts with upper and lower control limits and “special cause” variation by standard definitions were used to analyze outcomes.Figure 2.Proportion of patients with duration of 5 or fewer days compared to all duration in patients 2 years to 18 years old.

Results
A total of 34,324 patients were included. Rates of antibiotic prescribing remained high throughout the study (88 to 93%), with special cause variation detected (Figure 1). After EMR order-set development, increased compliance with recommended duration of 5 or fewer days was observed (3% to 83%), with special cause variation throughout the study (Figure 2). Rates of amoxicillin prescribing decreased throughout the study (77 to 74%), with special cause variation detected (Figure 3).Figure 3.Proportion of amoxicillin prescribed per all antibiotics in patients 61 days to 18 years old.

Conclusion
Implementation of an EHR order set resulted in shorter durations of prescribed antibiotics for AOM in patients older than 24 months. Antibiotic prescribing rates increased, and amoxicillin prescribing decreased throughout study period. The effect of the amoxicillin shortage, which started in October 2022, likely played a role in decreased amoxicillin prescribing rates. This project indicated that further dissemination of the new CCP and de-implementation of previous practices is needed to achieve improvement in antibiotic prescribing and first line antibiotic use.

Disclosures
All Authors: No reported disclosures
177. AMR-Informed Antibiotic Use Metrics
Authors: Goodman Reid , Bewley Alice , Atkinson Andrew , Fraser Victoria J , Vazquez Guillamet M Cristina 
Published: January 2025

Abstract

Background
Antimicrobial resistance (AMR) poses a significant public health threat, and efforts are underway to monitor and reduce unnecessary antibiotic usage. The Standardized Antibiotic Administration Ratio (SAAR) measures unit and hospital consumption of antibiotics by adjusting for facility characteristics. However, SAAR currently does not consider the prevalence rates of AMR that could justify or challenge antibiotic usage. Our objective is to develop an optimization function that identifies the best antibiotic choice for sepsis caused by Gram-negative bacilli (GNB). Optimization functions determine the optimal solution given specific constraints.

Methods
This observational cohort study included all adult patients meeting the CDC sepsis criteria and admitted to any of the 10 BJC acute care hospitals between 2016 and 2021. We focused on GNB isolated from clinical cultures, specifically the 17 most common species. We selected 15 commonly used antibiotics with activity against GNB (Table 1). Initially, we calculated the antibiotic weights to determine the relative coverage of each antibiotic, expressed as the ratio of GNB susceptible to all cultured GNB. The optimization function then constrained the optimal choice to the antibiotic with the lowest weight that still exhibited activity against the ultimately isolated strain. The resulting optimal antibiotic weights were averaged per hospital and study year and reported as a ratio to the weights of antibiotics used, akin to SAAR.

Results
Our study included 11,515 GNB cultures obtained from 9,531 patients. GNB were isolated from urine (40.5%), blood (20.5%), and respiratory specimens (20.3%). We present the antibiotic weights in Table 1, along with the representative ratios of empiric and directed observed-to-optimal antibiotic weights across BJC hospitals during the study period (Figs 1 and 2). Additionally, we contrast the SAAR trends for the same hospitals in Fig. 3.

Conclusion
Our optimization function selects the narrowest spectrum antibiotic and facilitates comparisons in antibiotic spectrum usage while considering existing AMR dynamics. It provides actionable insights and complements SAAR's metric of antibiotic duration.

Disclosures
M Cristina Vazquez Guillamet, MD, BNGO: Stocks/Bonds (Public Company)|Carisma Therapeutics: Stocks/Bonds (Public Company)|Ocugen: Stocks/Bonds (Public Company)
204. Clostridioides difficile screening among asymptomatic carriers admitted for bone marrow transplantation: Navigating optimal stewardship strategies
Authors: Hofmann Justin , Habib Alma , Tran Nikki , MacDowell Sarah , Choe Hannah , Liscynesky Christina , El Boghdadly Zeinab 
Published: January 2025

Abstract

Background
Toxigenic Clostridioides difficile (CD) approximately colonizes 11-39% of allogeneic and 13% of autologous hematopoietic stem cell transplantation (HCT) candidates. Colonization increases risk for CD infection (CDI). Thus, in 2018, our institution established universal CD PCR screening on admission to the HCT unit to decrease hospital onset CDI rates. CD colonized patients received primary prophylaxis with twice daily oral vancomycin (OV) if antibiotics were initiated. Here, we share our experience with this process and subsequent diagnostic and therapeutic stewardship interventions.

Methods
We retrospectively analyzed adult HCT patients who had stool CD PCR screening within 72 hours of HCT admission between 12/2018 to 8/2021. Outcomes were stratified by CD screen positive vs negative within 100 days post-HCT. CD PCR was the methodology used for CDI diagnosis during this time frame.

Results
We reviewed 237 patients (autoHCT, n=154; alloHCT, n=83). Patient characteristics are described in Table 1. Thirty alloHCT and 52 autoHCT patients screened positive for CD. Prior antibiotic use was observed more in the CD colonized group. Nine (11%) screen-positive patients developed CDI in 100 days versus 13 (8.4%) screen-negative. No significant differences in other outcomes were noted (Table 2). Diarrhea occurred in 76 (92.7%) of the screen-positive patients and 144 (92.9%) of the screen-negative. A second CD PCR test was ordered in 18 patients from the positive group and 129 from the negative group; 16 of 18 (88.9%) converted to a negative result without any CD-directed treatment and 9 of 129 (7%) became positive. In 9/2023, CD screening policy ceased in lieu of a 2-step CD PCR plus toxin A/B enzyme immunoassay (EIA) for clinical suspicion of CDI. This change reduced CDI rate and antibiotic utilization (Figures 1,2).Figure 1.Decrease in anti-CDI antimicrobial utilization in the bone marrow transplant unit over time following two-step CD testing implementation in 9/2023

Conclusion
Regardless of CD carrier status, diarrhea is an inevitable early post-HCT adverse effect due to commonly used conditioning chemotherapies for autoHCT and alloHCT. Screening for CD carriage on HCT admission may not accurately assess risk of future CDI and may only reflect transient carriage in some patients. Better CDI diagnostic tools such as 2-step test is needed in this population to avoid over diagnosis and treatment of CDI.Figure 2.Decrease in anti-CDI antimicrobial utilization and CDI rate of all patients (including non-transplant patients) admitted to the cancer center over time following two-step CD testing implementation

Disclosures
Hannah Choe, MD, Abbvie: Advisor/Consultant|Actinium: Advisor/Consultant|Incyte: Advisor/Consultant|Ironwood: Advisor/Consultant|Regimmune: Advisor/Consultant|Sanofi: Advisor/Consultant
303. The A-Stop Study: Rapid Tests for Candida Infection in Non-neutropenic Critically-ill Patients - A Multicentre Diagnostic Test Accuracy Study
Authors: McMullan Ronan 
Published: January 2025

Abstract

Background
Among critically-ill patients, antifungal therapy is usually driven by risk rather than a confirmed diagnosis. This leads to overtreatment, due to both low confidence in culture-based diagnostics and the time-critical nature of antifungal treatment. Such overtreatment undermines antimicrobial stewardship which could be improved if rapid, non-culture, tests reliably exclude disease.

Methods
This was a prospective multicentre diagnostic test accuracy study of three rapid tests for Candida infection: beta-D-glucan (BDG), Associates of Cape Cod, and two PCR-based tests (Fungiplex Candida, Bruker Corporation; & T2Candida, T2 Biosystems). In brief, patients were eligible for recruitment within 24hr of being started empirically on antifungal therapy for suspected Candida infection if they were not neutropenic. In the primary analysis, diagnostic accuracy metrics were derived by comparing index test results to the EORTC/MSGERC definition of proven Candida disease for patients in intensive care units (ICU). In a secondary analysis, the tests were compared with a constructed reference standard for proven + probable Candida disease. Since the purpose of these tests was to rule-out disease, sensitivity and negative predictive value (NPV) were the focus.

Results
Of 4005 patients screened for eligibility, 1251 participants were recruited from 57 UK ICUs between 2018-2023. Of these, 1223 were evaluable against the definition of proven disease and 54 met that definition. In total, 1215, 1217, and 507 participants had an evaluable BDG, Fungiplex, and T2Candida test, respectively. For proven disease, the most sensitive test was BDG (69%), followed by T2Candida (44%) and Fungiplex (28%); the NPV of each of these three tests was 97%. The sensitivity was predictably lower for the proven + probable disease group (N=124), ranging from 18%-58%, yet NPV remained above 90% for all three tests.

Conclusion
There is an opportunity to reduce unnecessary antifungal prescribing in this patient group. Each of the tests evaluated had lower sensitivity than previously reported but, because of low disease prevalence, they had high NPV. Modelling the effects of using the tests to stop empiric treatment may further guide how best to apply the tests in practice.

Disclosures
All Authors: No reported disclosures
304. Global Incidence of Viral Lower Respiratory Tract Disease (LRTD) Episodes and Hospitalizations (2010–2021)
Authors: Maslova Ekaterina , Fageras Malin , Gillespie Kate W , White Lisa , Raferty Quinn , Oros Andrei , Sinha Pratik 
Published: January 2025

Abstract

Background
The COVID-19 pandemic highlighted the impact of viruses on lower respiratory tract diseases (LRTD); however, the global burden of viral LRTD is undefined. To bridge this gap, we estimated the global incidence of viral LRTD and hospitalizations in 2010–21.
Figure 1. Global incident count of viral LRTD episodes by viral etiology (2010–2021). Non-viral causes are shown for comparison.

Methods
We used the Global Burden of Diseases, Injuries, and Risk Factors 2021 (GBD) framework and a Bayesian meta-regression tool (DisMod-MR 2.1) to estimate the global incidence of viral LRTD. We defined viral LRTD as clinician-diagnosed pneumonia/bronchiolitis, capturing symptoms such as cough, difficulty breathing, fever, and chest discomfort. Viral LRTD were categorized by pathogen (SARS-Cov2; influenza; respiratory syncytial virus [RSV]; ‘other’). We estimated hospitalizations by applying a country-specific scalar, informed by inpatient admission data and a country-specific healthcare access and quality index from the GBD, on pathogen-specific estimates of LRTD for each country. In data sparse regions, estimates were generated by extrapolation.Figure 2.Global incident count of viral LRTD hospitalizations, by viral etiology (2010–2021). Non-viral causes are shown for comparison.

Results
Average global incidence (per 100,000 person-years [PY]) of viral-associated LRTD episodes was 1,198 in 2010–19 and 25,716 in 2020–21. The number of viral LRTD cases was 880 million in 2010–19 and 4 billion in 2020–21. Average overall global incidence (per 100,000 PY) of viral LRTD hospitalizations was 170 (123 in 2010–19; 388 in 2020–21). The total number of hospitalizations was 90 million in 2010–19 and 61 million in 2020–21. Influenza and ‘other’ viruses accounted for most viral LRTD episodes (Figure 1) and hospitalizations in 2010–19 (Figure 2). Viral LRTD episode rates remained stable until 2019, while hospitalization rates increased. A decrease in influenza- and RSV-related episodes and hospitalizations was noted in 2020–21.

Conclusion
Viral LRTD are common and incur substantial global healthcare burden. Year-on-year increases in severe cases requiring hospitalization, most recently compounded by the COVID-19 pandemic, are alarming. Given the previously underappreciated scale of the problem, increased surveillance and novel therapeutic options may help reduce the burden of viral LRTD.

Disclosures
Ekaterina Maslova, ScD, AstraZeneca: Employee of AstraZeneca|AstraZeneca: Stocks/Bonds (Private Company) Malin Fageras, PhD, AstraZeneca: Full time employee|AstraZeneca: Stocks/Bonds (Private Company) Lisa White, PhD, AstraZeneca: Advisor/Consultant Pratik Sinha, MBChB/PhD, AstraZeneca: Advisor/Consultant|Prenosis Inc: Board Member
P-809. Evaluating the Usage, Safety, and Accuracy of Vancomycin Dosing Practices at VA Eastern Colorado Health Care System (VA ECHCS)
Authors: Hart Caitlin , Christoffersen James , Scott Catherine 
Published: January 2025

Abstract

Background
Vancomycin is a glycopeptide antibiotic used as a mainstay of therapy for gram positive bacterial infections, including MRSA (methicillin-resistant staphylococcus aureus). Vancomycin requires pharmacokinetic calculations to determine dosing and close therapeutic drug monitoring to achieve goal trough between 15-20 mg/L (AUC/MIC goal between 400-600 mg ■h/L) and prevent nephrotoxicity. The purpose of this study is to assess our current vancomycin usage patterns, including empiric dosing accuracy & safety outcomes to help inform a decision whether a change to our current practice is indicated.

Methods
This retrospective, observational cohort study evaluated 117 vancomycin trough levels from 63 patients who received at least two doses of vancomycin between August 1, 2022 and July 31, 2023. Patients were excluded if they received hemodialysis or were dosed by random levels in the setting of severe renal dysfunction. Collected demographics included age, sex, weight, height, BMI, indication for vancomycin, dosing, trough levels, source of infection, MRSA nares, concomitant nephrotoxic medications, spinal cord injury diagnosis, serum creatinine, and cystatin C. Estimated AUC was calculated using VancoPK.com based on the reported trough using patient specific pharmacokinetic parameters. This study is exempt from IRB approval.

Results
A total of 58 trough levels from 49 patients were included. The majority of patients were male (87.7%) with an average age 61±13 years old. Out of the 58 trough levels evaluated, 20 (41%) were at goal. Of the levels not a goal 27 (71%) were subtherapeutic, and 11 (29%) were supratherapeutic. The estimated AUC was at goal for 35 (60%) of the 58 total troughs. Of the 27 patients who had a subtherapeutic trough 21 (77%) had an AUC at goal, and 14 of them increased the dose despite having a therapeutic AUC. Only 1 patient (2%) developed possible vancomycin associated AKI (acute kidney injury).

Conclusion
A higher number of patients were within therapeutic range when evaluating AUC compared to trough. The low incidence of vancomycin associated AKI was likely due to low frequency of supratherapeutic troughs in this study. Further analysis of these results will be used to identify opportunities for education and improvement of our current vancomycin dosing process.

Disclosures
All Authors: No reported disclosures
P-814. Utility of PET-CT Scan in Staphylococcus aureus Bacteremia
Authors: Peterson Christopher , Tokala Mamata Reddy , Ndolo Ruth , Stocki Christopher , Stayrook Sydney , O’Shea John-Paul , Bansal Ekta , Espriella Mariana Gomez de la , Fazili Tasaduq 
Published: January 2025

Abstract

Background
Staphylococcus aureus bacteremia is a common yet serious infection with high morbidity and mortality. The timely identification of the primary source of infection and any associated metastatic foci is crucial for guiding appropriate management strategies and improving patient outcomes. Positron emission tomography-computed tomography (PET-CT) scans offer a non-invasive imaging modality that combines the metabolic information provided by PET with the anatomical detail provided by CT. Our investigation aims to show that PET-CT is a useful modality for improving mortality in patients with S. aureus bacteremia.Table 1:Demographic Variables of Participants

Methods
Patients with S. aureus bacteremia who underwent PET-CT at Roanoke Memorial Hospital between November 2020 and November 2022 were identified through electronic health records. These were matched with a control group comprised of patients with S. aureus bacteremia who did not undergo PET-CT scans. Logistic regression analysis was employed for statistical comparison between groups.Table 2:PET Group Results

Results
A total of 132 patients were included in the study, with 66 in both the PET group and the group without PET (Table 1). Patients undergoing PET-CT had significantly lower odds of mortality compared to those without the scan (OR=0.404, 95% CI: 0.167 - 0.980, p=0.0451). In the PET-CT group, PET-CT detected a new foci of infection in 57.6% of cases and a source control procedure was performed in 25.8% of cases as a result of PET-CT findings (Table 2). Subgroup analysis within the PET group showed positive PET scan uptake in the majority of patients (93.94%), with whole-body PET-CT being the most commonly performed imaging protocol. Antibiotic duration was adjusted in 33% of patients based on PET-CT findings. Patients in the PET-CT group received a longer course of antibiotics (36.8 vs 29.3 days)(Table 3).Table 3:Primary and secondary outcomes

Conclusion
These results underscore the potential clinical utility of PET-CT in guiding therapeutic interventions. Here we observed a lower mortality in patients with S. aureus bacteremia who underwent PET-CT imaging, as well as increased performance of source control procedures and longer antibiotic duration. PET-CT scans offer a comprehensive assessment of infection localization assisting clinicians in identifying occult foci of infection.

Disclosures
All Authors: No reported disclosures