ImportanceThere is a clear benefit to body armor against firearms; however, it remains unclear how these vests may influence day-to-day patient encounters when worn by emergency medical services (EMS).ObjectiveTo determine the association of ballistic vests worn by EMS clinicians with workplace violence (WPV) and disparities in care among racial and/or ethnic minority patients.Design, Setting, and ParticipantsProspective cohort study of a volunteer-based sample of EMS clinicians at a large, multistate EMS agency encompassing 15 ground sites across the Midwest from April 1, 2023, to March 31, 2024. Data were analyzed from May to June 2024.ExposureExternal ballistic armor being used by a group of self-selected clinicians on every run.Main Outcomes and MeasuresPrevalence and characteristics associated with WPV and with declines of treatment and/or transport compared between crews with 1 or more vested vs no vested members.ResultsA total of 156 of 415 staff (37.6%) opted in to wear the vests, including 77 male participants (49.4%). Prevalence of WPV was higher for vested crews (1.11 vs 0.85 cases per 100 runs; adjusted risk ratio [aRR], 1.28; 95% CI, 1.10 to 1.50; P = .001) and was due to higher rates of verbal abuse. The presence of 1 or more vested crew members increased the likelihood of all patients declining EMS treatment and/or transport; however, effect size was highest among patients with an unknown race and/or ethnicity (2234 [21.1%] vs 2134 [16.5%] patients; aRR, 1.19; 95% CI, 1.10 to 1.27; P < .001), followed by racial and/or ethnic minority patients (708 [16.7%] vs 399 [13.8%] patients; aRR, 1.18; 95% CI, 1.05 to 1.33; P = .01). Analyses of individual minority groups revealed a significant increase only in Black or African American patients declining treatment and/or transport by vested crews (461 [17.6%] vs 223 [13.7%] patients; RR, 1.28; 95% CI, 1.10 to 1.49; P = .002).Conclusions and RelevanceIn this cohort study, vested crews experienced increased prevalence of WPV compared with nonvested crews. Use of vests increased the frequency of all patients declining EMS treatment and/or transport. Among minority groups, there was a significant increase in Black or African American patients declining treatment and/or transport. Agencies should consider benefits and unintended consequences of EMS clinicians wearing body armor.
P-1666. Hematology-Oncology Unit-Specific Antibiogram: A Decade of Experience at a Large Academic Medical Center
Abstract Background Antibiograms are an important stewardship tool that can inform optimal empiric therapy; most antibiograms are hospital-wide. Unit-specific antibiogram data for unique patient populations including intensive care unit and pediatrics is robust; however, published experience with unit-specific antibiograms in the hematology-oncology (heme-onc) population is limited. These patients are unique because of the common use of antimicrobial prophylaxis, prolonged broad-spectrum antibiotics, and an immunocompromised state. We sought to examine the trends in antibiogram antimicrobial susceptibility over time. Methods This retrospective quality initiative included microbiology results (first isolates per patient per timeframe) from Mayo Clinic Rochester from 2012 to 2022. Eligible cultures were those identified as being obtained from one of 8 hematology, oncology, or bone marrow transplant inpatient units. Agar dilution susceptibility testing and Clinical and Laboratory Standards Institute (CLSI) breakpoints were used. Screening PCRs (eg, VRE PCR) were excluded. Culture and susceptibilities were identified by an EMR based report, compiled annually, and reported for two-year periods. Susceptibility rates were compared using the Chi-square test and Chi-square analysis for trends. Results There were 4 gram-negative and 5 gram-positive organism groups that met CLSI antibiogram criteria of ≥ 30 isolates and were included (tables 1-4). There were several significant differences in comparison to the hospital-wide antibiogram, with lower antibiotic susceptibility rates in the heme-onc units for multiple organisms, notably fluoroquinolones to E.coli and P. aeruginosa and several cephalosporins to Enterobacterales as well as penicillin and levofloxacin to Viridans group Streptococcus and vancomycin to E. faecium (tables 1&2). Over the period of 2012-2013 to 2021-2022, susceptibility rates remained stable among the heme-onc antibiogram, with few significant changes (tables 3&4). Conclusion Heme-onc antibiograms illustrated susceptibility rate differences compared to our hospital-wide antibiograms, particularly for antimicrobials used as prophylaxis. Through population-specific antibiograms, providers may be able to improve empiric antibiotic selection. Disclosures Christina G. Rivera (O'Connor), Pharm.D, Gilead Sciences: Board Member
P-1713. Impact of an Evidence-Based Order Panel on Antimicrobial Prescribing in Ambulatory Patients with Complicated and Uncomplicated Cystitis
Abstract Background Optimizing antimicrobial prescribing for urinary tract infections (UTI) represents an area of opportunity for ambulatory antimicrobial stewardship programs. A pre-populated, ambulatory antibiotic order panel for UTI was implemented in the Mayo Clinic Enterprise on 5/16/2022. The order panel provides antimicrobial regimens which align with both institutional and national treatment guidelines based on patient comorbidities, complicating factors, and beta-lactam allergy status. We aimed to assess the impact of panel use on antibiotic prescribing for complicated and uncomplicated cystitis in the ambulatory setting. Methods This retrospective review included ambulatory encounters from the Mayo Clinic Enterprise in 2022 and 2023. Eligible encounters were randomly selected and included those with a primary ICD-10 code of cystitis performed by primary care or urgent care clinicians. Encounters were excluded if patients had symptoms indicative of pyelonephritis, underwent urinary instrumentation within 30 days, or had a urinary pathogen isolated within 90 days. The primary outcome was concordance with institutional guidelines. Secondary outcomes included repeat healthcare contact and therapy duration. Outcomes were analyzed with Pearson's chi-squared and Wilcoxon rank sum tests (α level = 0.05). Results 793 encounters (397 panel vs. 396 non-panel) were included. Prescribing was guideline concordant in 79.3% and 64.9% (p< 0.001) of panel and non-panel encounters, respectively. Inappropriate duration was the most common reason for non-concordance in the panel use cohort. There was no difference between groups for repeat healthcare contact incidence. Antimicrobials prescribed differed between panel and no-panel groups (Table 1), with higher use of sulfamethoxazole/trimethoprim and lower use of cefdinir in the panel cohort. Numerically shorter durations were seen in the panel group, with more 3- and 5-day regimens than the no-panel group. Conclusion Use of a pre-populated antimicrobial order panel for outpatient cystitis encounters resulted in greater adherence to institutional guideline recommendations, particularly in terms of antimicrobial selection, without adversely impacting repeat healthcare contact. Disclosures Paschalis Vergidis, MD, MSc, AbbVie: Advisor/Consultant|Ansun Biopharma: Grant/Research Support|Cidara Therapeutics: Grant/Research Support|F2G: Grant/Research Support|Scynexis: Advisor/Consultant|Scynexis: Grant/Research Support
Discovery of a MET-driven monogenic cause of steatotic liver disease
Background and Aims: Metabolic dysfunction–associated steatotic liver disease affects about a third of adults worldwide and is projected soon to be the leading cause of liver cirrhosis. It occurs when fat accumulates in hepatocytes and can progress to metabolic dysfunction–associated steatohepatitis, liver cirrhosis, and HCC. Metabolic dysfunction–associated steatotic liver disease pathogenesis is believed to involve a combination of genetic and environmental risk factors. Single nucleotide polymorphisms have been implicated, but non-syndromic monogenic causes are lacking. Approach and Results: We identified a novel genetic variant in a familial case of metabolic dysfunction–associated steatohepatitis and performed deep variant functional analysis, including protein modeling, dynamics, and cell-based assays to assess molecular mechanisms of dysfunction and altered cellular signaling. We analyzed exome sequencing data of 3904 individuals with steatotic liver disease (SLD) to identify additional cases and establish the link between specific gene variants and SLD diagnosis. We discovered and functionally validated the NM_000245.4:c.3505A>T; p.(Ile1169Phe) variant in the MET (mesenchymal-epithelial transition) kinase domain as a monogenic cause of SLD. Subsequently, we detected additional ultra-rare, previously uninterpreted, and likely deleterious variants in MET from screening sequencing data. Among individuals with confirmed SLD based on electronic record review, 1.1% (45/3904) had rare predicted deleterious MET variants. Eight of 45 (17.7%) individuals had predicted deleterious variants in the MET kinase domain confirmed to be functionally like the familial case variant. Conclusions: We report the first germline nonmalignant rare MET -driven disease, a monogenic form of SLD.
P-1869. Utilizing Large Language Models for Enhanced Decision Support in Travel Medicine Clinic: our experience at Mayo Clinic
Abstract Background The integration of Generative AI (GAI) into healthcare systems is increasingly recognized for its potential to transform patient management. The primary aim of this research was to evaluate and quantify the performance of large language models (LLMs) in generating actionable travel medicine advice. Architectural design of the Travel Clinic LLM project. Four phases of Discovery, Design, Evaluation, and Implementation/Deployment. Methods This study utilized two iterative phases of evaluation. In the initial phase, LLMs were prompted with detailed clinical scenarios including demographic data, medical and immunization histories, and specific travel plans. These prompts were designed to mimic typical inquiries encountered in travel consultations. The LLMs' initial responses were generated using the CDC’s Yellow Book as a foundational knowledge base. In the subsequent phase, the prompts were refined for greater specificity and clarity, and the knowledge base was enhanced by transitioning to Travax’s Travelers’ Health database. Additional structured data inputs included an exhaustive list of vaccines from our pharmacy formulary and a detailed table of vaccine contraindications. The responses were evaluated and scored by ID clinicians from the Mayo Clinic. Results Initial findings after first iteration revealed limited efficacy with recall at 23.9%, an F1 score of 38.6%, accuracy also at 23.9%, and precision maintained at 100%, utilizing the CDC's Yellow Book. With the implementation of Travax and refined prompting techniques, preliminary results suggest a notable improvement in the quality of responses, though detailed scoring is presently underway. Improvements in the LLM’s performance can be attributed to several key adjustments: the adoption of a more comprehensive knowledge base, refined prompt engineering, and the incorporation of structured data to support more accurate and detailed recommendations. The collaborative engagement of Mayo Clinic with Google and Travax facilitated a synergistic approach to optimizing the AI model's utility and integration. Future plans include embedding the LLM into our EMR system. Conclusion The findings from this study highlight the significance of strategic collaborations between large healthcare centers, IT industry, and specialized knowledge database firms in effectively harnessing GAI for clinical use. Disclosures All Authors: No reported disclosures
P-773. Mycobacterium Tuberculosis Liver Abscess in Kidney Transplant Recipients
Abstract Background Recipients of solid organ transplant (SOT) have higher risk for infections, and the prevalence of mycobacterium tuberculosis liver abscess (MTB-LA) without pulmonary/disseminated MTB is 0.34%. However, there is little research on MTB-LA in SOT recipients. Mycobacterium tuberculosis Liver Abscess Cases Upon extensive literature review, this chart details all published, English-language cases of mycobacterium tuberculosis liver abscess in solid organ transplant recipients. Methods We conducted an extensive literature review of MTB-LA in adult SOT recipients. Results Our review showed 4 cases of MTB-LA in SOT recipients (table below). We detail 1 additional case. A 58-year-old male with ESRD due to type 2 diabetes mellitus, and latent MTB underwent kidney transplantation in March 2023. He completed a 6-month course of isoniazid and vitamin B6 for latent MTB 1 month before transplant. His post-operative course was uncomplicated; he was discharged to follow up with his nephrologist. He later developed norovirus illness with fever, which was conservatively managed. He developed new fevers 3 months post-transplant and CT of the abdomen/pelvis revealed a liver abscess, which was treated with empiric broad spectrum antibiotics, and was not amenable to aspiration. At his 4-month post-transplantation, he complained of fatigue, night sweats, poor appetite, and weight loss requiring hospitalization, wherein an MRI of the abdomen/pelvis identified a 3.6 x 3.2 x 6.2 cm liver abscess. The liver abscess aspirate was positive on acid fast bacilli smear and MTB polymerase chain reaction. He was initiated on antituberculosis therapy with isoniazid, rifabutin, pyrazinamide, and ethambutol. Susceptibilities identified pyrazinamide resistance, and led to substitution with levofloxacin. Labs, imaging and microbiology testing were negative for evidence of pulmonary/disseminated MTB. His donor’s information was reviewed; no obvious risk factors for active MTB were found. The recipient of the mate kidney is doing well without evidence of MTB infection. After 2 months of 4-drug antituberculosis therapy, ethambutol was discontinued. CT scan of the abdomen and pelvis at 4 months post anti-tuberculosus therapy revealed a 3 cm area of residual inflammation at the site of prior MTB-LA, in the setting of resolution of prior symptoms. Conclusion Early imaging and diagnostic aspiration of liver abscess with specific stains, culture and PCR testing can facilitate rapid diagnosis and initiation of antituberculosis therapy. Disclosures All Authors: No reported disclosures
P-832. The Skip Phenomenon in Patients with Staphylococcus lugdunensis Bloodstream Infection
Abstract Background Staphylococcus lugdunensis (SL) is a coagulase-negative staphylococcus with virulence comparable to that of Staphylococcus aureus. The “skip phenomenon” (SP) is a pattern where blood cultures are intermittently negative before final clearance of bloodstream infection (BSI). SP is well-documented in S. aureus bacteremia but has not been described previously in SL. In this report, we present a cohort with SL BSI and describe its prevalence and their clinical features and outcomes. Methods We conducted a retrospective review of patients with blood cultures positive for SL in samples referred to the Mayo Clinic reference lab between June 2012 and June 2022. We assessed clinical characteristics, including time to positivity, prevalence of the skip phenomenon (defined by a positive culture after 24 hours of negative cultures), patient demographics including Charlson Comorbidity Index, mortality and length of hospital stay. Results We identified 55 patients with SL BSI and 33 of them had enough laboratory data to determine the prevalence of the skip phenomenon. SP was present in 5 of 33 (15.2%) patients. For all patients with SL BSI, the median age was 67 years (interquartile range [IQR] 61-79); mean CCI in the group with SP was 5.6 (standard deviation 2) and those without SP was 5.9 (standard deviation 2.7); median duration of bacteremia was 3 days (IQR 1-4); median hospital length of stay was 14 days (IQR 8-20); and 1-year mortality was 45%. Oxacillin susceptibility was present in 33 of 34 cases. Conclusion A total of 15% of patient cases with SL BSI demonstrated the SP. Recognition of the SP in patients with SL BSI is important as this may impact duration of antibiotic therapy and timing of long-term cardiovascular device placement. Disclosures Larry M. Baddour, MD, UpToDate, Inc.: Royalty payments (authorship duties).
P-70. Outcome of Gram-Negative Periprosthetic Joint Infection after Primary and Revision Total Hip and Knee Arthroplasty
Abstract Background Gram-negative bacteria (GNB) account for 5-23% of all periprosthetic joint infections (PJI), following total knee or hip arthroplasties (TKA, THA). Literature on the management of Gram-negative PJI is limited. This study aimed to describe our experience with the presentation, management, and outcomes of Gram-negative PJI.Table 1:Baseline characteristics (N = 126 cases)Data are N (%) unless otherwise specified. Abbreviations: BMT; Bone-marrow transplant, CCI; Charlson comorbidity index, CPPD; Calcium pyrophosphate crystal deposition, CRP; C-reactive protein, DMARDs; Disease-modifying antirheumatic drugs, ESR; Erythrocyte sedimentation rate, GERD; Gastroesophageal reflux disease, IQR; Inter-quartile range, PJI; prosthetic joint infection, SD; Standard deviation, TNF; Tumor necrotic factor, WBC; white blood cell Methods A retrospective review of our infected institutional total joint registry from 2012-2023 identified 125 patients with 126 GNB PJI (60 THA and 66 TKA) according to MSIS criteria for PJI. Seventy-two cases (57%) of GNB PJI in this series were classified as acute based on the duration of symptoms of less than 4 weeks. Treatment failure was defined as reoperation for any reason, persistent infection, or reinfection post-surgery. Baseline demographics, presenting symptoms, microbiological data, and treatment outcomes were reviewed.Table 2:Therapies (N = 126 joints)Data are N (%) unless otherwise specified. Abbreviations: DAIR; Debridement, antibiotics, and implant retention, IQR; Inter-quartile range Results For baseline demographics, see Table 1. Notably, 10% of patients included in the study were immunosuppressed. Fifty-five cases (43.6%) had a history of revision prior to the diagnosis of PJI, including 44 cases with history of prior PJI. Pseudomonas aeruginosa was the most commonly isolated pathogen (31.7%). Wound drainage was associated with polymicrobial growth (40.8%). Debridement, antibiotics, and implant retention (DAIR) was utilized in 42 cases with 9.8% failure rate. History of revision arthroplasty, chronic PJI and the presence of sinus tract were associated with higher odds of reoperation within 1 year. Eighty-four cases underwent resection arthroplasty (RA), 73 had antimicrobial spacer, of those, 60 patients completed two-stage revision (TSR). At the time of reimplantation, 45/60 (75%) of cases had negative cultures (Table 2). The overall failure rate in resection group failure rate was 45.2%. Wound drainage was associated with higher odds of reoperation in this group (Table 3). The Failure rate in this cohort was 33%. Fluoroquinolones had a 90% susceptibility rate but were used infrequently for chronic suppression (25%).Table 3:Predictor factors with reoperation for any reason within 1 yearData are N (%) unless otherwise specified.Abbreviations: DAIR; Debridement, antibiotics, and implant retention, PJI; Prosthetic joint infection Conclusion Pseudomonas aeruginosa was the predominant pathogen in GNB PJI, with a high failure rate observed in the resection group. History of revision arthroplasty, chronic PJI, sinus tracts and wound drainage were associated with increased risk of reoperation within 1 year.Figure 1:Distribution of failure events across the study Disclosures Nicholas Bedard, MD, Stryker: Advisor/Consultant
Artificial intelligence-enhanced electrocardiogram left ventricular diastolic function assessment for prognostic assessment in mitral annulus calcification
Abstract Background Moderate-severe mitral annulus calcification (MAC) and left ventricular (LV) diastolic dysfunction are both linked to increased risks of heart failure and mortality. Assessing LV diastolic function (LVDF) in moderate-severe-MAC by echocardiography is frequently challenging and unreliable. We recently validated an AI-ECG model for LVDF. We aimed to determine if this tool can predict long-term mortality in patients with moderate-severe-MAC and whether it can help establish MAC-specific echocardiographic LVDF parameter cutoffs. Methods This retrospective study included all patients from the AI-ECG LVDF study test cohort who underwent comprehensive transthoracic echocardiography confirming moderate-severe-MAC and ECG within fourteen days of each other at Mayo Clinic between 09/2001 and 06/2022. AI-ECG LVDF was determined based on the index ECG. Patients were categorized based on AI-ECG into groups representing normal/grade-1 LVDF, grade-2 LVDF, or grade-3 LVDG (DF-1, DF-2, and DF-3, respectively). Results Of 2,506 patients with moderate-severe-MAC [mean age 77, 64.1% females], 709 (28.3%), 1,510 (60.3%), and 287 (11.5%) were classified as DF-1, DF-2, and DF-3, respectively. Worse LVDF grade was associated with older age, male sex, lower LV ejection fraction, and higher rates of noncardiovascular and cardiovascular comorbidities. Over a median follow-up of 2.8 years, 1,059 (42.3%) patients died. In multivariable survival analysis, DF-2 [adjusted hazard ratio (aHR) 1.43, 95% confidence interval (95%CI) 1.21-1.68] and DF-3 (aHR 1.54, 95%CI 1.22-1.93) were independently associated with a higher risk of death (figure). Findings were also consistent after adjusting to mitral inflow gradients. When comparing LVDF echocardiographic parameters in controls without MAC matched by age, sex, left ventricular ejection fraction, and AI-ECG DF grade, significant differences were observed. Patients with moderate to severe MAC generally exhibited lower e' velocities, higher TR velocities, elevated E/e' ratios, and increased LAVi. Interestingly, the E/A ratio between MAC patients and their matched controls across AI-ECG LVDF grades remained consistent. Conclusion AI-ECG LVDF predicts mortality risk in patients with moderate-severe-MAC, regardless of mitral inflow gradients. Utilizing AI-ECG LVDF might aid in the risk stratification of patients with significant MAC.
Abstract Background Bezlotoxumab is a monoclonal antibody infusion approved to prevent recurrence of Clostridioides difficile infection (CDI). The objective of this study was to explore outcomes associated with bezlotoxumab use at three academic medical centers. Methods A retrospective cohort study was conducted with 180 patients who received bezlotoxumab from May 2018 through November 2023. The primary outcome was recurrence of CDI within 12 weeks of receipt of bezlotoxumab. The study also sought to evaluate risk factors for CDI recurrence in patients who received bezlotoxumab. Results Of the 180 patients who received bezlotoxumab at our institution, 165 were included in the study. Fifteen patients were excluded because they did not improve with standard of care CDI treatment. In the study cohort, 45% were immunosuppressed (n=75), 17% had a solid organ transplant (n=28), and 16% had a history of inflammatory bowel disease (n=27). Ninety-five percent of patients received bezlotoxumab as an outpatient (n=156). Recurrence of CDI within 12 weeks occurred in 16% of patients. Duration from diagnosis of CDI to bezlotoxumab infusion (p=0.022) and having greater than two prior CDI episodes (p=0.032) were statistically significant predictors for CDI recurrence within 30 days. Conclusion Our study demonstrated similar CDI recurrence rates for patients who received bezlotoxumab in a real-world setting compared to previous clinical trials. Patients with CDI may benefit from receiving bezlotoxumab earlier in the course of illness and prior to developing multiple recurrences. Disclosures Robert Orenstein, DO, FACP, Ferring: Advisor/Consultant|Ferring: Honoraria