Administration Of Antibiotics Research Articles

Prophylactic antibiotic use in trauma patients with non-operative facial fractures: A prospective AAST multicenter trial.

Craniofacial trauma affects approximately 3 million individuals in the United States annually. Historically, low overall data quality and inadequate sample size have limited the development of clinical practice guidelines for prophylactic antibiotic use in facial fractures. We sought to examine the current use patterns and effects of prophylactic antibiotics in non-operative facial fractures. A prospective analysis of adult patients with nonoperative facial fractures was conducted across 19 centers from January 2022 to December 2023. Kruskal-Wallis H, Mann-Whitney U, Pearson's χ2, Fisher's exact tests, and logistic regression models were used to evaluate the association between antibiotic duration (no antibiotics, ≤24 hours, and >24 hours) and facial fracture-associated infectious complications. Among 1,835 patients, 1,168 (63.7%) received no antibiotics and 667 (36.4%) received antibiotics (≤24 hours, n = 264 (14.4%); >24 hours, n = 403 (22.0%). Nineteen (1.0%) patients developed infectious complications (0.7% in the no antibiotic group vs. 1.7% with antibiotics). Most patients (99.0%) did not develop an infection despite the majority (63.7%) receiving no antibiotics. Injuries were predominately closed fractures (86.3%), without mucosal disruption (83.9%) or foreign bodies (97.7%). Antibiotic administration had a statistically significant association with the occurrence of infectious complications (p = 0.050). However, no significant association was seen between antibiotic duration and infectious complications following multivariable logistic regression, adjusting for confounders (≤24 hours: adjusted odds ratio, 1.24; 95% confidence interval, 0.30-5.14; p = 0.766; >24 hours: adjusted odds ratio, 1.32; 95% confidence interval, 0.37-4.69; p = 0.668). Despite most patients not receiving antibiotics, infection rates remained low. This indicates prophylactic antibiotic use does not reduce the risk of fracture-associated infections for most injury patterns. While a randomized trial is optimal to validate these data, at this time, there is no evidence to support presumptive antibiotics for closed non-operative facial fractures. Therapeutic/Care Management; Level II.

Renal Abscess Associated with SGLT2 Inhibitors Administration in Heart Failure Without Other Previous Risk Factors: A Case Report

Background and Clinical Significance: Renal abscess represents one infectious urological complication with lethal potential. The treatment of this pathology may differ depending on the severity of the symptoms and the size of the infectious collection. Diabetes, immunosuppression, and associated urinary pathologies are most frequently responsible for the development of abscesses. This case report presents the first documented case of a renal abscess associated with Sodium-glucose cotransporter 2 (SGLT2) inhibitors in a person without previous predisposing pathologies. Case Presentation: A 62-year-old patient presented to the emergency department for pain in the right flank, vomiting, and dysuria. The patient’s medical history revealed Heart Failure New York Heart Association (NYHA) Class II, Coronary Artery Disease (CAD) with prior angioplasty, and permanent Atrial Fibrillation. No prior urological or immunosuppressive conditions were detected. The Computed Tomography (CT) evaluation confirmed the ultrasound suspicion of a right renal abscess performed in the emergency room. The only risk factor identified was the initiation of SGLT2 inhibitor therapy for cardiac pathology approximately 2 months before. According to the small dimensions and urine culture, the abscess was successfully treated with antibiotic administration in collaboration with the urology department. The infectious process was remitted within 2 weeks. Conclusions: To our knowledge this is the first documented case of a renal abscess associated with SGLT2 inhibitor administration in a person without previous predisposing risk factors. Despite the relatively low incidence of urinary tract infections (UTIs) associated with SGLT2 inhibitors, their widespread use in the treatment of various socially significant conditions highlights the need for both patients and medical specialists to be aware of all potential risks and pay increased attention to these cases.

Focused Review of Enhanced Recovery After Abdominal Trauma Surgery in the Pediatric Population and Development of a Pediatric Enhanced Recovery After Trauma Surgery Pathway.

Traumatic injuries are the leading cause of morbidity and mortality amongst pediatric patients; improving outcomes after pediatric abdominal trauma surgery could be quite impactful. Although enhanced recovery after surgery (ERAS) pathways have been successfully employed in adult trauma patients, there are few studies on pediatric enhanced recovery after abdominal trauma surgery and no consensus post trauma surgery guidelines for children. A systematic search of the existing literature for pediatric enhanced recovery after trauma surgery pathways was performed by two independent authors. However, no pediatric enhanced recovery after trauma surgery pathways were found. Therefore, we reviewed the pediatric and adult enhanced recovery after trauma surgery literature to identify potential impactful elements of care that could be part of a pediatric pathway. The existing literature supports the incorporation of several elements into pediatric trauma ERAS pathway. We propose a pediatric enhanced recovery after trauma surgery pathway, which highlights several principles of ERAS pathways (multimodal analgesia, goal-directed fluid therapy, early initiation of nutrition, timely administration of antibiotics, avoidance of hypothermia, DVT prophylaxis, the early removal of drains and indwelling catheters, and patient education).

Modern Management of Severe Open Fractures of the Extremities

➢ The administration of antibiotics, revascularization, effective initial debridement, stabilization, and dead-space management are important time-dependent, acute actions.➢ Following the adequate resuscitation of the patient and the local soft tissues, the first stage of the Masquelet technique is performed together with the definitive coverage of the soft-tissue defect.➢ The optimal time for the second stage (grafting of the bone defect) depends on the progress of the soft-tissue reconstruction and the overall state of the patient. It is usually at 6 to 14 weeks.➢ Bone graft involves cancellous autograft; depending on the volume of the defect, it can be acquired using different donor sites and methods and can be combined with cancellous allograft, bone substitutes, bone marrow aspirate, and inductive molecules.➢ Bone healing is independent of the size of the defect, assuming that revascularization of the graft material has not been disturbed.➢ The development of signs of a fracture-related infection in the clinical setting of a severe open fracture dictates surgical treatment and pathogen-specific antibiotics, debridement of the membrane and the surrounding soft tissues, and reinitiation of the staged process of limb salvage.➢ The results of staged management of severe open fractures with bone defects are reproducible and good.

Understanding and mapping the antibiotic prescribing and administration process in assisted living facilities

Understanding and mapping the antibiotic prescribing and administration process in assisted living facilities

Antimicrobial Treatment Options for Multidrug Resistant Gram-Negative Pathogens in Bone and Joint Infections

Multidrug (MDR) and extensive drug (XDR) resistance in Gram-negative bacteria (GNB) emerges worldwide. Although bone and joint infections are mostly caused by Gram-positive bacteria, mainly Staphylococci, MDR GNB substantially increase also as a complication of hospitalization and previous antibiotic administration. This narrative review analyzes the epidemiological trend, current experimental data, and clinical experience with available therapeutic options for the difficult to treat (DTR) GNB implicated in bone and joint infections with or without orthopedic implants. The radical debridement and removal of the implant is adequate therapy for most cases, along with prompt and prolonged combined antimicrobial treatment by older and novel antibiotics. Current research and clinical data suggest that fluoroquinolones well penetrate bone tissue and are associated with improved outcomes in DTR GNB; if not available, carbapenems can be used in cases of MDR GNB. For XDR GNB, colistin, fosfomycin, tigecycline, and novel β-lactam/β-lactamase inhibitors can be initiated as combination schemas in intravenous administration, along with local elution from impregnated spacers. However, current data are scarce and large multicenter studies are mandatory in the field.

Change in Vancomycin Absorption after Intraperitoneal Injection and Correlation between Intraperitoneal Vancomycin Absorption and Peritoneal Equilibration Test Score in Mice with Peritoneal Injuries

Peritonitis is a serious complication in peritoneal dialysis patients and requires antibiotic administration. Intraperitoneal vancomycin is an empiric therapy for peritonitis caused by Gram-positive cocci; however, there is no way to predict vancomycin absorption after intraperitoneal administration. Therefore, we aimed to evaluate the changes in vancomycin absorption after intraperitoneal injection into mice with chlorhexidine gluconate (CG) induced peritoneal injuries. Additionally, we examined the correlation between intraperitoneal vancomycin absorption and peritoneal equilibration test (PET) score. PET score was determined using glucose concentration in the peritoneal dialysis fluid at each dwell time (Dt) and D2 (2 h of dwell time)/D0 (0 h of dwell time) glucose ratio. Vancomycin was injected into the peritoneal cavity of mice, blood was collected after 1-8 h, and peritoneal fluid was recovered. The residual ratio of intraperitoneal vancomycin was significantly decreased in the CG group at all time points compared to that in the vehicle group. CG group significantly exhibited higher serum vancomycin concentrations than the vehicle group, and the maximum serum concentration increased depending on CG concentration, with 0.05 and 0.1% CG groups showing 3.9- and 6.1-times higher vancomycin concentrations, respectively, than the vehicle group. A significant correlation was observed between the Dt/D0 glucose ratios and residual vancomycin ratios in the peritoneal fluid 2 or 6 h after intraperitoneal injection. A good correlation was observed between the D2/D0 glucose and residual vancomycin ratios 6 h after intraperitoneal vancomycin injection. Thus, PET score can predict residual intraperitoneal vancomycin, aiding in dosing decisions.

P-2235. Implementation of a Host-Protein Test (MMBV) Into Routine Care for Children Hospitalized with Symptoms of Lower Respiratory Tract Infection

Abstract Background Infectious etiology is often unclear in children hospitalized with symptoms of lower respiratory tract infection (LRTI), driving antibiotic misuse. A host-protein test (MMBV) exhibits high diagnostic accuracy for differentiating bacterial from viral etiology. Best practices for test implementation should be established. We evaluate the effectiveness of implementing MMBV into routine care without specific antimicrobial stewardship (AMS) education by assessing impact on antibiotic administration to children hospitalized with LRTI symptoms. Patient flow Eligibility required age 3 months to 5 years old and hospitalized with 1 or more of the following signs or symptoms that concern for lower respiratory tract infection (LRTI): accessory muscle use, chest pain, cough, crepitation or rales, decreased breath sound, dyspnea, prolonged expiration, wheezing. MMBV, MeMed BV. Methods Retrospective pragmatic study of MMBV implementation at a single medical center without specific AMS education. Children 3 months to 5 years old hospitalized with LRTI symptoms were included. In the non-interventional arm (2014-2017) MMBV results were not available in time to impact antibiotic decisions. In the interventional arm (2021-2022) MMBV results were rapidly available. Patients were assigned into discharge diagnosis classes: bronchiolitis, community acquired pneumonia (CAP), viral diagnosis and other diagnosis. Antibiotic administration was compared between arms per diagnosis class. The relative reduction in antibiotic administration in the interventional arm versus the non-interventional arm according to discharge diagnosis class There was a relative reduction in antibiotic administration in the interventional arm relative to the non-interventional arm from 60.0% (12/20) to 22.5% (9/40) for bronchiolitis; from 98.7% (74/75) to 97.3% (71/73) for CAP; from 15.0% (12/80) to 13.3% (6/45) for viral diagnosis; and from 60.7% (51/84) to 51.8% (43/83) for other diagnosis. P-values were calculated using Richardson’s method. CAP, community-acquired pneumonia. Results Age, sex and MMBV results were similar across arms. Viral MMBV rates were high (39%-90%) across all diagnosis classes in the non-interventional (n=259) and interventional (n=241) arms. A significant relative reduction in antibiotic administration of 62.5% (p=0.004) was attained in patients discharged with bronchiolitis without impacting length of stay (p=0.530). Non-significant reductions in antibiotic administration were observed for CAP, viral diagnosis and other diagnosis. Conclusion MMBV availability is associated with judicious antibiotic administration to children hospitalized with bronchiolitis without AMS education. Combining MMBV introduction with AMS education is required to reduce potentially unwarranted antibiotics in children hospitalized with CAP. Disclosures All Authors: No reported disclosures

P-1776. Impact of Sepsis Recognition Tools and Pharmacy Workflow on Sepsis Management and Outcomes

Abstract Background CDC 2023 Hospital Sepsis Program Core Elements prioritizes protocolized care, timely and effective antibiotics and de-escalation. At NYULH, robust sepsis tools integrated into Epic since July 2021 include the Sepsis Indicator Column on the Emergency Department (ED) Track Board for patient identification, nurse and physician-driven Best Practice Advisory (BPA), ED Sepsis Quick List for antimicrobial orders, and Sepsis Guidelines. Sepsis antibiotics in the ED are administered as IV push over 3 minutes followed by IV piggyback since March 2021. Methods We conducted a retrospective review of adult patients with community-onset sepsis and confirmed bacteremia who presented to ED between 9/2022 and 5/2023. The primary outcomes were time to antibiotics and the percent of patients with ineffective empiric antibiotics. Secondary outcomes included time to de-escalation and sepsis outcomes. As a process measure, we evaluated sepsis guidelines adherence and pharmacy interventions. Results During 9/2022 to 8/2023, 1682 ED sepsis cases were recorded, and 22% had bacteremia. Among 109 included patients, median Charlson Comorbidity Index was 6 (IQR 3-8) and Pitt bacteremia score 0 (IQR 0-1). Median time from ED sepsis recognition to antibiotic verification by pharmacy was 9 min (IQR 0-27) with median time to antibiotic administration of 29 min (IQR 15-50). Ineffective initial therapy occurred in 11% of cases with median time to effective antibiotics at 24 h. De-escalation was seen in 84% of cases with median time of 2 days for both MRSA and atypical coverage discontinuation and 4 days for Pseudomonas coverage. Initial therapy adhered to guidelines in 70.6% of cases, and deviation primarily occurred due to the administration of vancomycin in the absence of MRSA risk factors. Antibiotic-related pharmacy and stewardship (ASP) recommendations were made in 40% of patients while in ED and 96% of patients during hospital stay. In-hospital mortality, ICU admission, 30-day infection related re-admission and C. difficile infection within 6 months were 8.3%, 42.2%, 8.3% and 1.8%, respectively. Conclusion The integration of Epic sepsis recognition tools with ASP and pharmacy workflows led to high rates of timely and effective antibiotic administration in the ED and de-escalation during hospitalization. Disclosures All Authors: No reported disclosures

P-424. Challenges in Developing a Non Ventilator Hospital-Acquired Pneumonia Surveillance System

Abstract Background Pneumonia has been identified as the leading cause of hospital-acquired infections (HAI) with Non Ventilator Hospital-Acquired Pneumonia (NVHAP) making up the majority of cases. The ambiguity of definitions and subjective diagnostic criteria make defining and tracking NVHAP cases a challenge. We attempted to duplicate a previously validated electronic medical record (EMR) based NVHAP surveillance systems at a Midwest Academic Medical Institution. Defining NV HAP Inclusion criteria for NVHAP. Methods Using previously established criteria a surveillance system was designed to determine possible cases of NVHAP using data from our institution’s EMR (Table 1). Institutional review board approval was obtained, and the surveillance system was retrospectively applied to adult patients hospitalized throughout 2023 at two Midwest academic hospitals. A validation study was conducted to compare ten percent of cases reported by the NVHAP surveillance system to that of a single physician reviewer. Interim analysis was conducted in instances of inclusion criteria failure to allow for refinement of the NVHAP surveillance system. Results The NVHAP surveillance system generated a list of 425 possible NVHAP events in 2023. Single reviewer analysis of 20 patients revealed 12 patients who did not meet CDC pneumonia criteria and three that did not meet all inclusion criteria: two for lack of chest imaging within 48 hours of recorded oxygen deterioration event and two with no documentation of new antibiotic administration. Additional lists of 338, 322, and 76 NVHAP episodes were generated after coding changes were implemented with repeat interim analysis demonstrating further issues with adherence to inclusion criteria and errors with reproducibility of data extraction. Conclusion The development of a NVHAP surveillance system would allow an objective way to track this significant HAI. Potential models exist for creating such a system. However, multiple challenges are still present from determining EMR specific coding for complex medical issues, such as oxygen deterioration events, to reproducibility of electronic extracted data. Our efforts show that even when attempting to replicate validated methodologies site specific challenges will pose significant barriers to the development of EMR based NVHAP surveillance systems. Disclosures Kelly Cawcutt, MD, MS, BD: Advisor/Consultant|BMJ: Honoraria

P-1699. Antimicrobial Administration and 30-Day Outcomes in Patients Hospitalized with MRSA-Related Infections who Self-Discharge

Abstract Background Management of serious infectious diseases typically includes hospitalization and IV antibiotics, particularly where methicillin-resistant Staphylococcus aureus (MRSA) is the causative organism. When patients with these infections decide to self-discharge, it presents a challenging clinical decision for their providers. Here we describe antimicrobial prescribing practices for patients hospitalized with different infectious disease diagnoses and their 30-day outcomes. Methods This retrospective cohort study included patients 18 years and older admitted between January 1, 2010, and December 31, 2019, with admission blood cultures growing MRSA. Veterans Affairs (VA) electronic health data was extracted from the Veterans Informatics and Computing Infrastructure, microbiology data, inpatient antibiotic administration, discharge antibiotic prescriptions, ICD-9- and ICD-10-CM coded infectious disease discharge diagnoses, discharge type (self-discharge or regular discharge), as well as 30-day all-cause mortality and readmission. Descriptive statistics were used to compare antibiotic prescribing for specific infectious diseases between self- and regular discharges. Results While hospitalizations with patients self-discharging were lower for each infectious disease, their total antibiotic days were similar for most listed MRSA-related infections. However, for 30-day readmission rates, there was a higher rate among self-discharged patients for most all infections except cardiovascular. Conversely, 30-day mortality appeared to be higher among regular discharges for most infectious disease diagnoses except central nervous system and bloodstream infections. Conclusion While this analysis is preliminary, there is a concerning trend towards higher 30-day readmissions for patients with MRSA infections who self-discharge, despite similar durations of MRSA-directed antibiotic prescribing. This suggests additional factor(s) than antibiotic administration that play a role in readmissions for this patient population. Further research is needed to elucidate what factors contribute to readmission for patients who self-discharge from hospitalization for serious MRSA-related infections. Disclosures All Authors: No reported disclosures

P-1746. Evaluating Microbiology Reporting on Time to Appropriate Therapy for Organisms Producing Extended-spectrum and AmpC β-lactamases

Abstract Background Our Antimicrobial Stewardship Program (ASP) implemented specific treatment recommendations and suppression of select susceptibility results for microbiology reports positive for extended-spectrum β-lactamases (ESBL) and AmpC producing organisms. These statements also recommend Infectious Diseases (ID) consult if needed. This change is in alignment with the Clinical and Laboratory Standards Institute (CLSI) recommendations.Figure 1:Microbiology lab reporting statementsA. ESBL organism statements. B. AmpC organism statements. Methods This study was a single-center, retrospective cohort of adult patients with monomicrobial infections due to organisms at high-risk for AmpC or ESBL production. The intervention was effective February 28th, 2023. See Figure 1. Data was collected by chart review for pre- and post-intervention groups from April 1st to September 30th, 2022, and April 1st to September 30th, 2023, respectively. The primary outcome was the time to appropriate definitive antibiotic administration. Appropriate antibiotic therapy was defined by the Infectious Diseases Society of America (IDSA) 2023 Guidance on the Treatment of Antimicrobial Resistant Gram-Negative Infections guidelines. Secondary outcomes included guideline-adherent antibiotic therapy, frequency of ID consultations, and inappropriate antibiotic de-escalation. Results Time to appropriate antibiotic administration was not significantly different between the pre- and post-intervention group (median time 8.6 hours vs. 8.3 hours, respectively). The frequency that patients received guideline-adherent therapy significantly increased between groups (pre- 67% vs post- 81%, p = 0.024). ID consultations also significantly increased (pre- 52% vs post- 77%, p = 0.005). Inappropriate de-escalation of therapy based on susceptibilities significantly decreased between groups (pre- 12% vs post- 2%, p = 0.047). Conclusion The implementation of microbiology reporting statements increased guideline-adherent definitive antibiotic therapy, increased ID consultations and decreased inappropriate antibiotic de-escalation. Disclosures All Authors: No reported disclosures

P-846. A Single-Institution Retrospective Analysis on the Administration of Beta-lactam Antibiotics Prior to Vancomycin in Bacteremic Patients

Abstract Background According to the 2021 IDSA Surviving Sepsis Guidelines, prompt administration of antibiotics is an essential recommendation for patients with bacteremia. Similarly to a recent study published by Amoah et al., we sought to determine if the sequence of antibiotic administration impacted 30-day mortality. Methods We conducted a single-institution retrospective study at Baylor Scott & White Medical Center in Temple, Texas, on patients greater than 18 years of age admitted with sepsis and confirmed bacteremia from January 1st, 2021, to July 1st, 2023 who received sequential antibiotic administration with a Beta-lactam and vancomycin within the first 6 hours of admission time. Our primary endpoint was odds ratio for 30-day mortality. Results Of 6143 patients generated from electronic search, 222 patients were included in the Beta-lactam first group and 16 were included in the vancomycin first group. Of these 238 patients, 132 patients were admitted to the ICU upon admission. The most common Beta-lactam antibiotic administered was piperacillin-tazobactam (58.40%) followed by Cefepime (25.47%), then Ceftriaxone (13.03%). For patients with monomicrobial bacteremia, the most common organisms isolated were Escherichia coli (25.21%), Methicillin resistant Staphylococcus aureus (MRSA) (13.45%), Methicillin sensitive Staphylococcus aureus (MSSA) (11.34%), and Proteus mirabilis (7.56%). The calculated odds ratio for 30-day mortality was 0.40 (95% CI 0.089-1.831), indicating a decreased occurrence of mortality within 30 days for patients who received Beta-lactam antibiotics first, though this result was not statistically significant due to limited sample size, particularly within the vancomycin first group. Conclusion Although not statistically significant, our results suggest that prompt administration of Beta-lactam antibiotics prior to vancomycin may have mortality benefit in patients with bacteremia. Further confirmatory studies will be required to investigate this principle. Disclosures All Authors: No reported disclosures

P-884. A Scenario-Based Survey of Clinician Recommendations for Follow-up Blood Cultures in Patients with Varying Risk of Persistent Gram-Negative Bacteremia

Abstract Background Studies examining the impact of follow-up blood cultures (FUBCs) in patients with gram-negative bacteremia (GNB) have shown mixed results. In practice, FUBCs are variably obtained. Understanding practice variation and motivation for ordering FUBCs is important to determine how providers stratify patients at high risk for persistent GNB.Figure 1:Global distribution of survey respondents (n=864). Methods We surveyed clinicians (physicians, pharmacists, clinical microbiologists, physician assistants, nurses, medical trainees) globally between 2/21/24-4/9/2024 to understand when they would obtain FUBCs in patients with GNB using 10 hypothetical patient scenarios. Scenarios were generated by varying age, clinical status after 48 h of antibiotics, and risk of persistent GNB based on our published AIMS scoring tool (Antibiotics, Infection source, Medical conditions, Serratia). The survey contained 4 low-risk cases (AIMS 0-1), 3 intermediate-risk cases (AIMS 2-3), and 3 high-risk cases (AIMS 4-6). This anonymous web-based survey was distributed through listservs, email, and social media.Table 1:Demographic characteristics of survey respondents (n=864). Results In total, 864 respondents from 50 different countries and 6 continents (Figure 1) opened the survey and provided 791 recommendations on FUBC ordering (791/864; 91.5%). Respondent demographics are described in Table 1. Most respondents were physicians (86.5%) specializing in infectious diseases (79.7%) who were within 10 years of training completion (52.3%); a plurality managed least 6-10 cases of GNB/month (22.7%). FUBCs were frequently recommended, with >40% of respondents recommending FUBCs in 7/10 scenarios. Fair inter-respondent agreement was seen across all scenarios (Fleiss kappa 0.27), with notable agreement for cases with high AIMS scores (Fleiss kappa 0.24) (Figure 2). Patient age and clinical status after antibiotic administration were not associated with FUBC recommendations. Survey results of FUBC recommendations by individual case scenario (1-10) stratified by low, intermediate, and high risk AIMS scores. Bar graphs represent percentage of recommendations in favor (yes) or not in favor (No) of FUBCs in patients with GNB. Conclusion In this survey study, clinicians risk stratified hypothetical patients with GNB when assessing the need for FUBC. There was fair agreement among clinicians that high risk patients should get FUBCs. Future studies should focus on variables which prompt FUBC ordering in low-risk patients, an area of disagreement among responders, and ideally in the form of randomized clinical trial. Disclosures Joshua T. Thaden, MD, PhD, National Institutes of Health K08 AI171183 (Thaden): Grant/Research Support Vance G. Fowler, MD, MHS, Affinergy: Advisor/Consultant|ArcBio: Stocks/Bonds (Private Company)|Armata: Advisor/Consultant|Astra Zeneca: Advisor/Consultant|Astra Zeneca: Grant/Research Support|Basilea: Advisor/Consultant|Basilea: Grant/Research Support|ContraFect: Advisor/Consultant|ContraFect: Grant/Research Support|Debiopharm: Advisor/Consultant|Destiny: Advisor/Consultant|EDE: Grant/Research Support|Genentech: Advisor/Consultant|Genentech: Grant/Research Support|GSK: Advisor/Consultant|Janssen: Advisor/Consultant|Karius: Grant/Research Support|MedImmune: Grant/Research Support|Merck: Grant/Research Support|sepsis diagnostics: Patent pending|UptoDate: Royalties|Valanbuio: Stocks/Bonds (Private Company)|Valanbuio: Stocks/Bonds (Private Company) Sonali Advani, MBBS, MPH, FIDSA, Biomerieux: Advisor/Consultant|GSK: Advisor/Consultant|Locus Biosciences: Advisor/Consultant|Sysmex America: Advisor/Consultant Stacey Maskarinec, MD, PHD, National Institutes of Health K23 HL159275 (Maskarinec): Grant/Research Support

P-1409. Differential Impact of a Penicillin Allergy Assessment Tool on Orthopedic Surgical Patients from Areas of High Social Vulnerability

Abstract Background Penicillin allergy labels (PAL) have been associated with increased risk of surgical site infections. Many penicillin allergy assessment tools are being trialed to improve perioperative β-lactam utilization. We report on the sociodemographic characteristics associated with receipt of β-lactam antibiotics (BLA) in orthopedic surgical patients with a PAL after implementation of a penicillin allergy assessment tool built into the electronic health record (EHR).Table 1:Clinical and Sociodemographic Characteristics of Penicillin Allergy Label Patients by Preoperative β-Lactam Antibiotic (BLA) Administration Following Implementation of Penicillin Allergy Assessment Tool in the Electronic Health Record Methods We performed a retrospective cohort study of patients who underwent hip (HPRO) and knee arthroplasty (KPRO) procedures in a large health system between August 2022 and December 2023. Patients with a PAL were identified and demographic, clinical and antibiotic administration data were obtained from the EHR. Clinical data was merged with Social Vulnerability Index (SVI) census-track data comprising 4 subthemes (socioeconomic status, household characteristics, racial/ethnic minority status and housing type/transportation). Higher SVI indicates higher vulnerability. Patients with a PAL who did and did not receive a BLA post protocol implementation were compared.Figure 1:Impact of a Penicillin Allergy Assessment Tool on Beta Lactam Utilization in Patients who Live in High vs Low Social Vulnerability Index Census Tracks*Statistically significant p<0.05 Results 1851 patients with a PAL who had undergone a HPRO and/or KPRO were identified. After implementation of the penicillin allergy assessment tool, 443 (24%) did not receive a BLA preoperatively. PAL Patients that did not receive a BLA after implementation of the tool were more likely to be female and less likely to have an admit status at the time of surgery. Other clinical characteristics including surgical site infection rates were similar between the groups. (Table 1) PAL patients who did not receive BLA were more likely to live in areas with higher socioeconomic status SVI (26% vs 20%), higher household characteristics SVI (27% > vs 22%), and higher housing type SVI (20% vs 15%) than those who did receive BLA. (Figure 1) Conclusion Following implementation of an electronic penicillin assessment tool, most patients with a PAL were able to receive BLA safely. The subset of PAL patients who still did not receive BLA more frequently lived in areas with increased social vulnerability. Additional efforts may be needed to ensure the full benefit of tools is achieved in operative patients from areas with high SVI. Disclosures All Authors: No reported disclosures

P-1490. Evaluating the Impact of Inadequate Empiric Gram-Negative Antibiotic Therapy on Clinical Outcomes

Abstract Background Many clinicians select broad-spectrum antibiotic therapy based on the concern that inadequate empiric coverage will be associated with a worse outcome. To explore this concern, we compared outcomes between patients started on empiric narrow-spectrum antibiotics and later escalated to broad-spectrum antibiotics v. patients started empirically on broad-spectrum antibiotics and then continued on broad-spectrum antibiotics.Figure 1.Antibiotic Classification Methods We conducted a retrospective observational cohort study of adult patients discharged in 2019 from 120 hospitals in the Premier Healthcare Database. Encounters for adult patients were included if associated with (1) initiation of narrow- or broad-spectrum Gram-negative antibiotics on hospital day 0-2 and (2) administration of a broad-spectrum Gram-negative antibiotic as definitive therapy (see Fig. 1 for classification of antibiotics as narrow v. broad). Patients who received empiric narrow-spectrum antibiotics were matched to patients who received empiric broad-spectrum antibiotics using propensity scores. A win ratio was estimated to compare a ranked composite outcome including mortality, readmission, and adverse drug events between the two groups (see Fig. 2 for outcome structure).Figure 2.Components of Overall Clinical Outcome including Desirability of Outcome Ranking (DOOR) Results 81,826 patients who received empiric narrow-spectrum antibiotics were matched to 81,826 patients who received empiric broad-spectrum antibiotics (see Table 1 for patient characteristics). Mortality was lower (8.9% v. 9.2%, p = 0.022), readmission was less frequent (11.1% v. 12.7%, p < 0.0001), and adverse events were more frequent (10.5% v. 9.0%, p < 0.0001) after empiric narrow-spectrum antibiotics than empiric broad-spectrum antibiotics (see Table 2 for outcomes). Head-to-head comparison of ranked outcomes between the two groups suggested better clinical outcomes associated with empiric narrow-spectrum antibiotics (win ratio 1.04, p = 0.0007).Table 1.Characteristics of Patients in the Overall and Matched Cohorts Conclusion In a large propensity score-matched analysis of observational clinical data, starting empiric narrow-spectrum antibiotic therapy and needing to escalate to broad-spectrum antibiotic therapy later was not associated with worse clinical outcomes. Our findings challenge traditional guidance on how to select empiric antibiotic coverage.Table 2.Distribution of DOOR by Empiric Treatment Group in the Matched Cohort Disclosures Kimberly C. Claeys, PharmD, PhD, bioMérieux: Advisor/Consultant|bioMérieux: Honoraria Anthony Harris, MD, MPH, Innoviva: Advisor/Consultant|UpToDate: Infection Control Editor

P-1249. Analysis of Drug Interaction Between Valproic acid and Carbapenems

Abstract Background Carbapenems are broad spectrum antibiotics widely used for treatment of various infectious disease such as pneumonia, sepsis, and urinary tract infection. Carbapenems have been linked to a possible drug interaction which can lead to subtherapeutic levels of valproate and increase the risk of patients experiencing seizures. In this study, we reviewed cases of concomitant use of valproic acid and carbapenems, and investigated the impact of drug-drug interactions and effects. Methods The electronic medical records of patients treated with carbapenems and valproic acid at Seoul National University Bundang Hospital from 2017 to 2022 were reviewed. Results During the study period, a total of 183 patients were prescribed concomitantly with valproic acid and carbapenems. The average age was 64 years, 172 (94%) were >18 years of age and 11 (6%) were ≤ 18 years. The most common reason for carbapenem prescription were urinary tract infection (48.1%), pneumonia (38.3%), sepsis (24.6%), and intra-abdominal infection (5.5%). Among carbapenems, ertapenem was most common by 61.8%, followed by meropenem (39.9%), and imipenem (3.3%). Of the total cases, valproic acid monotherapy accounted for 42.6% and concomitant use with other anticonvulsants accounted for 57.4%. During concomitant use of carbapenem and valproic acid, 35.0% of patients were consulted to the infectious diseases or neurology departments about drug interactions, and 44.8% monitored the therapeutic drug concentration. During the concomitant treatment, valproic acid dosage was increased in 19.1% and other anticonvulsants were added in 12.0%. Seizure occurred in 15 cases (8.2%) of the total cases. Conclusion As a result of investigating drug-drug interactions between carbapenem and valproic acid, serum concentrations of valproic acid were significantly decreased, some of which actually led to convulsions. Care should be taken when administering carbapenem to patients receiving valproic acid. If concomitant administration is unavoidable, it is important to monitor serum concentrations and consider alternative anticonvulsants. Continuing education and monitoring of therapeutic drug concentrations are required for the concomitant administration of carbapenem antibiotics and valproic acid. Disclosures All Authors: No reported disclosures

P-1614. Verigene's Impact on Time to Preferred Antibiotics in Gram Positive Bacteremia

Abstract Background Utilization of rapid identification methods for positive blood cultures has been instrumental in the efforts of antimicrobial stewardship programs (ASPs). Studies have shown that the use of molecular testing techniques on positive blood cultures, which identify select bacteria and their genetic resistance, have enabled timelier initiation of targeted therapy. Type of Bacteremia Species of bacteremia identified in both the standard identification period and the identification by Verigene period Methods Data was collected via chart review over two separate 6-month periods (7/1/2021- 1/1/2022 and 7/1/2022-1/1/2023), with Verigene BCID having been implemented in June 2022. The primary endpoint was the time to preferred therapy for organisms reported in the Verigene gram-positive panel, including MSSA, MRSA, Enterococcus species (faecalis and faecium), VRE, and Streptococcus species. Demographic variables, the source of bacteremia when established (i.e., skin/soft tissue, urinary, etc), as well as interventions for source control were also collected. Source of Bacteremia Results In this study, we analyzed a total of 168 cases of gram-positive bacteremia. Among these, 94 cases occurred between 7/1/2021-1/1/2022 with identification via the standard method, while 74 cases occurred between 7/1/2022-1/1/2023 with identification via Verigene BCID. The average age of patients at the onset of bacteremia was 68 years, with a predominance of males (94.6%). Common underlying comorbidities included diabetes (50%) and coronary artery disease (48.7%). Regarding bacteremia etiology, 29.8% were caused by MSSA, 22.6% by MRSA, 32.7% by Streptococcus species, 11.3% by Enterococcus spp, and 6% by VRE. The most common primary source of bacteremia was identified as skin and soft tissue (34.5%). The time to administration of preferred antibiotics, as defined by our ASP recommendations, showed improvement across all gram-positive bacteremia types, decreasing from a mean of 61.5 hours with standard identification methods to 36 hours with Verigene identification. Time to preferred therapy decreased from 81.4 hours to 39.8 hours for MSSA bacteremia, and from 61.9 hours to 39.5 hours for Strep bacteremia. Time to Preferred Antibiotics Time in hours to preferred antibiotics for all cases analyzed, Streptococcus species, and MSSA. Conclusion The implementation of rapid blood culture identification utilizing Verigene BCID technology lead to a significant improvement in time to preferred antibiotics in cases of gram positive bacteremia. Disclosures All Authors: No reported disclosures

P-403. Incidence of Surgical Site Infections in Selected Tertiary Care Hospitals in Bangladesh: Findings From A Pilot Surveillance Project

Abstract Background Surgical site infections (SSI) are the most frequent type of healthcare-associated infections (HAI) and SSIs have substantial healthcare ramifications. In Bangladesh, most hospitals lack surveillance systems for HAIs, including SSI. We conducted this SSI surveillance to assess the rate and determine measures of SSI burden in Bangladesh Common Organisms for Surgical Site Infections in Bangladesh Common Organisms for Surgical Site Infections in Bangladesh Methods From January to August 2021, we piloted SSI surveillance in four tertiary care hospitals. Participants included undergoing cesarean section (C-section) or abdominal surgery. We enrolled SSI cases if any infection occurred within 30 days of the surgery and contained the skin, subcutaneous tissue and/or deep soft tissue, in or on any part of the anatomy. We also collected data on symptoms, antibiotic consumption, diagnosis, and treatment Results We enrolled 1,760 patients, with a majority (75.7%) undergoing C-sections. Within 30 days of surgery, 33.2% (585) of patients developed SSI symptoms. Abdominal surgery patients had a higher rate of SSI (40.9%, 175/426) compared to C-section patients (30.7%, 410/1334). Most patients (90.9%, 532/585) acquired SSI symptoms during hospital stay. Two-thirds (66.4%) of patients were prescribed antibiotics on admission, and 70.1% were given surgical antibiotic prophylaxis. Rates of SSI did not differ between those who received antibiotics or not. The most frequently prescribed antibiotics were ceftriaxone 57.5%, on admission and the combination of ceftriaxone and metronidazole (84.1%) in postoperative patients. Only 10. 7% (63/585) of participants performed wound cultures, of which 76.2% (48/63) demonstrated growth. The most frequently reported organisms were Escherichia coli (37.2%), Staphylococcus aureus (30.2%), and Klebsiella pneumoniae (20.9%). Conclusion Further study of the factors contributing to this high incidence and timing for surgical antibiotic prophylaxis administration is needed. The high rate of antibiotic consumption also suggests a need for examination of whether appropriate treatment is being administered and/or if antibiotic prophylaxis is targeting the correct organisms. Additionally, strengthening IPC practices, establishing antimicrobial stewardship programs, and updating antibiotic guidelines could help prevent SSIs and AMR in Bangladeshi hospitals Disclosures All Authors: No reported disclosures

Assessment of viable Enterobacteriaceae and Enterococcus spp. across the agro-ecosystem of an antibiotic-free swine farm.

Agricultural practices, specifically the use of antibiotics and other biocides, have repercussions on human, animal and plant health. The aim of this study was to evaluate the levels of Enterobacteriaceae and Enterococcus, as antibiotic resistant marker bacteria, in various matrices across the agro-ecosystem of an antibiotic-free swine farm in Quebec (Canada), namely pig feed, feces, manure, agricultural soil, water and sediment from a crossing stream, and soil from nearby forests. Samples were collected in fall 2022, spring and fall 2023 and spring 2024. All samples were subjected to counts of total, cefotaxime- and ciprofloxacin-resistant Enterobacteriaceae as well as total and vancomycin-resistant Enterococcus spp. The frequency of total and cefotaxime-resistant Enterobacteriaceae along with the vancomycin-resistant Enterococcus decreased with age in pig feces, from weaning to the end of the fattening period. High proportions of the Enterobacteriaceae recovered from feces and environmental samples were resistant to cefotaxime. Application of manure on fields contributed a significant input of Enterococcus, but those resistant to vancomycin were under the detection limit. This study shows the prevalence of antibiotic-resistant bacteria in a farm agro-ecosystem even without the administration of antibiotics to the animals, and highlights the complexity of components influencing antimicrobial resistance in the environment.