Objective Sternal wound infection (SWI) is a devastating complication following cardiac surgery. Although most SWI are bacterial and well described, Candida SWI remains poorly characterized. This study aimed to examine the clinical characteristics, management, and outcomes of Candida SWI. Methods We retrospectively reviewed the data of patients with Candida SWI following cardiac surgery at Baylor St. Luke's Medical Center between 2013 and 2024. Results Of the 11,108 cardiac surgeries, 55 Candida SWI were identified: superficial (10.9%), deep (21.8%), sternal osteomyelitis (40.0%), and mediastinitis (27.3%). Most occurred within 90 days postoperatively (70.9%). Candida albicans was most common (69.1%), followed by C. parapsilosis (12.7%), C. glabrata (9.1%), and C.tropicalis (7.3%). Surgical intervention was performed in 87.3% of the patients, and 60.0% received antifungal therapy for >6 weeks. The ninety-day mortality was 20.0%. In-hospital mortality was significantly associated with postoperative mechanical ventilation >48 hours [100% (in-hospital death group) vs. 63.9% (survivor group), OR: 17.38, 95% CI, 0.95-316.99; P =.008] and a lack of surgical debridement [26.4% (in-hospital death group) vs. 6.8% (survivor group), OR: 0.14, 95% CI, 0.02-0.79, P =.023]. However, it was not associated with mediastinitis [54.5% (in-hospital death group) vs. 20.5% (survivor group), OR: 4.41, 95% CI, 1.15-16.90; P =.052]. Mediastinitis was associated with a longer cardiopulmonary bypass time [213 min (mediastinitis group) vs. 142.5 min (non-mediastinitis group), P =.005] and extended postoperative hospital stays [55 days (mediastinitis group) vs. 36 days (non-mediastinitis group), P =.027]. Conclusions Candida SWI presented with variable extents and onsets. Despite aggressive surgical management and prolonged antifungal therapy, the prognosis remains challenging.

Background:Emergency department (ED) urine culture stewardship may reduce low-value testing, but downstream effects on antibiotic use and postdischarge utilization remain uncertain. Methods:We evaluated an intervention in which an infectious diseases physician and microbiologist reviewed pyuric urinalysis-with-reflex encounters, assessed culture indications, and contacted clinicians to recommend cancellation when absent. Adult ED encounters from February-July 2025 to September 2025-February 2026 were included; August was washout. Outcomes were urinalysis with reflex within 24 hours, urine culture within 24 hours, antibiotic days of therapy (DOT) per 100 patient-days, length of stay (LOS), and 30-day ED revisit among ED discharges. We fit biweekly interrupted time series models. Results:Among 17,621 encounters, the intervention was associated with lower postintervention slopes for urinalysis with reflex within 24 hours (-0.5 percentage points per biweekly period; 95% CI, -0.9 to -0.1) and urine culture within 24 hours (-0.2 percentage points; 95% CI, -0.4 to -0.0). DOT showed no sustained change (postintervention slope change, 0.00; 95% CI, -0.23 to 0.24). LOS showed a lower postintervention slope (-0.05 d; 95% CI, -0.08 to -0.02). Thirty-day ED revisit showed a higher postintervention slope (0.8 percentage points; 95% CI, 0.3 to 1.3). Conclusions:The intervention reduced urinary testing but did not reduce antibiotic DOT and was associated with increased 30-day ED revisit. Diagnostic stewardship in the ED may need to be paired with antimicrobial stewardship and prospective safety monitoring.

Background: Asymptomatic bacteriuria (ASB) is common in older adults; however, its treatment in this population is not beneficial and can be harmful. We developed an intervention to update the indications on a urinalysis and urine culture order set according to recent Infectious Diseases Society of America (IDSA) guidelines recommending against testing and treatment for bacteriuria in older adults with altered mental status (AMS) or falls. Methods: This retrospective quasi-experimental study included adult patients > 65 years who presented to an Emergency Department (ED) in Southeast Texas from July 2018 to February 2024. The intervention, implemented in June 2020, included a change in the urinalysis (UA) with reflex to urine culture order set that replaced “AMS” as an indication for UA with “AMS and fever or leukocytosis” and provider education. The study’s primary outcome was whether urine studies were obtained within 24 hours of presentation to the ED. Secondary outcomes were antibiotic days of therapy (DOT) for suspected UTI, length of stay (LOS), and 30-day hospital readmission. The difference in differences (DID) technique was used to assess the impact of the intervention on older adults who presented with AMS or a fall (cases) compared to those with other chief complaints (controls). Outcomes were evaluated using multiple regression models (logistic for urinary studies ordered and readmission, linear for log LOS, and zero-inflated negative binomials for DOT) adjusted for patient demographics and comorbidities. Results: The study included 31,626 patients. Almost a third of older adult patients who presented to the ED with a fall or AMS (31.5%) received urinary testing, and 5.9% received antibiotics. 20.2% of control patients received urinary testing in the ED, and 6.3% received antibiotics. After adjusting for confounders, the intervention did not impact the percentage of tests ordered [(DID OR 1.14, 95% CI 0.93 – 1.40), (Figure 1)]. The incident rate ratio (IRR) of not receiving antibiotics was similar after the intervention (IRR 0.78, 95% CI 0.54 – 1.13), while the baseline number of antibiotics a patient received increased (IRR 1.54, 95% CI 1.05 – 2.27). Conclusions: Modifying UA indications on the urinalysis order set did not reduce testing or treatment for bacteriuria in older adults presenting with AMS or a fall. Longer-term or repetitive educational interventions could be an effective way to improve long-term stewardship outcomes in this population, especially for providers with less exposure to guidelines. Further discussion and investigation are needed.

Abstract Background The management of bloodstream infections (BSIs) may be improved with rapid diagnostic identification. The updated Biofire FilmArray blood culture identification (BCID) 2 panel is able to detect extended-spectrum beta-lactamase and additional carbapenemase encoding genes amongst other resistance markers, allowing for earlier antimicrobial stewardship interventions. The purpose of this study was to evaluate the time to optimal antimicrobial therapy. Methods This was a single-center retrospective chart review of patients before and after the implementation of the updated BCID panel (BCID1 vs. BCID2, respectively). Adult patients were eligible for inclusion if they had a positive blood culture with an accompanying BCID panel result. Patients were excluded if they received concomitant treatment for an unrelated infection or had monomicrobial BSI with Staphylococcus species. The primary endpoint was time to initiation of optimal antimicrobial therapy from index blood culture, defined as pathogen and resistance gene directed therapy per hospital treatment algorithm. Secondary endpoints included time to active antimicrobial therapy, defined as empiric therapy shown to be active against index isolate(s) with an antimicrobial susceptibility report, and 30-day mortality. Results Overall, 143 patients were included in the BCID1 group and 175 patients in the BCID2 group. Time to optimal antimicrobial therapy was shorter in the BCID2 group compared to the BCID1 group (17.1 hours vs. 29.3 hours; p < 0.05). Time to active therapy was shorter in the BCID2 group compared to the BCID1 group (3.1 hours vs. 5.9 hours; p=0.03). Thirty-day mortality rate was lower in the BCID2 group compared to the BCID1 group (9.7% vs. 20.9%; p < 0.05). Conclusion Time to optimal and active antimicrobial therapy were significantly shorter after the implementation of the BCID2 panel. Furthermore, 30-day mortality was lower, indicating that optimized therapy per local hospital treatment algorithms may improve outcomes. Disclosures All Authors: No reported disclosures

We developed an intervention to update the indications on a urinalysis and urine culture order set according to recent guidelines recommending against testing and treatment for bacteriuria in older adults with altered mental status or falls. The intervention had no impact on diagnostic or antibiotic stewardship.

BACKGROUND:Vancomycin ranks among the most utilized antimicrobial agents in the treatment of serious β-lactam-resistant gram-positive infections, but its use has been associated with nephrotoxicity. Reduction of acute kidney injury (AKI) has been reported in preclinical models with adjuvant montelukast. The purpose of the study was to ascertain if montelukast was associated with a reduction in the prevalence of vancomycin-associated AKI. METHODS:This retrospective cohort study examined adult patients who received intravenous vancomycin between January 2020 and January 2024. The RIFLE criteria (risk, injury, failure, loss, and end-stage kidney disease) were employed in identifying cases of AKI. Additionally, a preclinical vancomycin-associated nephrotoxicity model was established to provide insights into possible renal protective mechanisms. RESULTS:Patients receiving montelukast (n = 110) were compared with controls (n = 330), of which AKI was observed in 3 (2.7%) vs 35 (10.6%), respectively (P = .01). A multivariate logistic regression analysis revealed that weight (odds ratio [OR], 1.02; 95% CI, 1.006-1.03; P = .005) and intensive care unit admission (OR, 6.88; 95% CI, 2.96-18.8; P < .001) were independently associated with AKI, while montelukast (OR, 0.26; 95% CI, .06-.77; P = .03) and male gender were protective (OR, 0.41; 95% CI, .19-.85; P = .02). Our in vitro model also revealed that adjuvant montelukast can reduce injury to proximal tubule cells through activation of the p62/KEAP-1/HO-1 antioxidant pathway. CONCLUSIONS:Our study suggests that montelukast during vancomycin therapy may be protective against AKI, which may reduce patient harm and hospitalization costs. Further studies are warranted to validate our findings prospectively.

Background:Invasive candidiasis including candidemia is a common healthcare-associated infections with significant morbidity and mortality. The USA does not have mandatory national surveillance for mucocutaneous or invasive candidiasis which complicates estimation of epidemiology and outcomes. The aim of this project was to describe the epidemiology, mortality, and Candida-associated hospital readmissions in hospitalized patients with Candida species infections. Methods:This secondary database analysis used clinical microbiology data from adults hospitalized at three large health systems (25-hospitals) in the Greater Houston area totaling over 1.6 million hospitalization days per year from 2018 to 2023. Proportion and rates of Candida cultures per 10,000 hospitalization days were calculated. Risk factors for mortality and Candida-associated readmissions were assessed by multivariable logistic regression. Results:Within the study period, 7514 hospitalized patients aged 64 ± 16 years (mean± standard deviation (SD)) with 10,183 unique Candida cultures were identified. Majority of Candida cultures were nosocomial (59%) with wide variability in mean time to positive culture (9 ± 44 days) after admission. Candida specimens were from blood (32%), abdomen (29%), or mucocutaneous (24%) cultures and most commonly C. albicans (44%) or C. glabrata (21%). C. auris increased significantly from 2% of cultures from 2018-20 to 5% in 2021-23 (p < 0.0001). Length of hospital stay was 21 ± 34 days and inpatient mortality was 17%. Multivariable analyses identified hospitalization variables and Candida species predictive of inpatient all-cause mortality and Candida-associated readmissions after initial hospitalization. Conclusion:These analyses highlight the significant burden of candidiasis and the emergence of new strains, including C. auris. Ongoing surveillance can refine burden estimates and assess the impact of stewardship and infection control interventions.

Abstract Background Vancomycin is the most common antimicrobial used for the treatment of serious infections implicated by β-lactam resistant Gram-positive bacteria but has been associated with acute kidney injury (AKI) in up to 43% of cases. Reduction in renal injury associated with nephrotoxins has been reported in an animal model with adjuvant montelukast. However, it is unclear if this protective effect could be translated to improve patient outcomes. The objective of this study was to ascertain if montelukast is correlated with reduced vancomycin-associated AKI. Methods We conducted a retrospective study of adults (≥ 18 years) who received intravenous vancomycin at our institution between 01/2020-01/2024. Patients were included if they met these criteria: vancomycin therapy ≥ 3 days and baseline serum creatinine (SCr) < 1.5 mg/dL. Patients who received concomitant montelukast (intervention) were compared to those without (control). The primary outcome was the prevalence of AKI (rise in SCr ≥ 1.5x baseline) as defined by Risk, Injury, Failure, Loss, or End-stage kidney disease (RIFLE) criteria. The primary outcome was compared using the Fisher’s exact test while the duration of vancomycin therapy was compared by the Student’s t test. Independent risk factors associated with AKI were identified by multivariate logistic regression. Results Of 1739 patients screened, 110 patients were included in the intervention arm and 330 in the control. Patients received vancomycin for similar durations (mean ± SD, 5.1 ± 4.1 vs 5.9 ± 3.3 days, respectively; P = 0.06) and serum trough concentrations were comparable (P = 0.39). The intervention cohort experienced 2.7% AKI compared with 10.6% in the control (P = 0.01). The multivariate logistic regression analysis revealed that weight (OR, 1.02; 95% CI, 1.004 to 1.03; P = 0.011) and intensive care unit admission (OR, 6.9; 95% CI, 2.8 to 17.1; P < 0.001) were independently associated with acute kidney injury, while montelukast was protective (OR, 0.29; 95% CI, 0.09 to 0.98; P = 0.046). Conclusion This study suggests that montelukast may be protective against vancomycin-associated nephrotoxicity, which may reduce patient harm and healthcare costs. Additional studies to investigate the nephroprotective mechanism will be conducted to corroborate these findings. Disclosures All Authors: No reported disclosures

Cefiderocol is a siderophore cephalosporin designed to target multi-drug-resistant Gram-negative bacteria. Previously, the emergence of cefiderocol non-susceptibility has been associated with mutations in the chromosomal cephalosporinase (PDC) along with mutations in the PirA and PiuA/D TonB-dependent receptor pathways. Here, we report a clinical case of cefiderocol-resistant P. aeruginosa that emerged in a patient during treatment. This resistance was associated with mutations not previously reported, suggesting potential novel pathways to cefiderocol resistance.

Abstract Background Ceftriaxone (CRO) is commonly utilized for the treatment of Gram-negative infections. However, there are limited data on the appropriate dose of CRO for the treatment of Gram-negative bacteremia. This study aimed to assess the clinical outcomes of CRO 2 grams versus 1 gram daily for Gram-negative bacteremia. Methods This was a retrospective, single-center study of patients with Gram-negative bacteremia that received CRO for ≥ 72 hours or over 50% of treatment duration as definitive treatment. Patients were excluded if they had polymicrobial bacteremia, had bacteremia with a Gram-negative organism that was resistant to CRO, or received empiric antibiotics other than CRO for ≥ 72 hours. Definitive treatment was defined as antibiotic utilized after the antibiotic susceptibility report was available to the clinician. Treatment failure was defined as antibiotic escalation due to clinical worsening at any time during CRO therapy. The primary endpoint for this study was 30-day hospital mortality. Secondary endpoints were treatment failure, readmission rates, and adverse reactions. Results Of 127 patients included, 57% received CRO 2 grams and 43% received 1 gram. The mean APACHE-II score did not differ between the 2 grams and 1 gram groups (13.8 ± 5.97 versus 12.5 ± 5.61, respectively; p = 0.238). Hypoalbuminemia was present in 21% of patients in the 2 grams group compared to 20% in the 1 gram group (p = 1.00). The most common Gram-negative bacteria isolated were Escherichia coli and Klebsiella species in 68% and 24% of patients, respectively. Hospital mortality in the entire cohort was 4% (n = 127). Patients receiving 2 grams had a numerically higher 30-day hospital mortality rate (7% versus 0%; p = 0.069). Patients receiving 2 grams also had numerically higher rates of treatment failure (15% versus 5%; p = 0.094). Readmission due to infection did not differ between groups (8% versus 5%; p = 0.731). Overall, ceftriaxone was well tolerated in both groups with no reported adverse reactions. Conclusion There was no significant difference in hospital mortality among patients treated with ceftriaxone 2 grams versus 1 gram for Gram-negative bacteremia. Disclosures All Authors: No reported disclosures

Abstract Background Stenotrophomonas maltophilia can cause nosocomial infections in immunocompromised hosts and patients with indwelling devices or broad-spectrum antibiotic exposure. Treatment of S maltophilia infections poses a challenge due to intrinsic resistance mechanisms, including inducible L1 metallo and L2 cephalosporinase beta-lactamases. Trimethoprim-sulfamethoxazole (SXT) is recognized as the agent of choice for S maltophilia infections. Outcomes with alternative antimicrobials are not well described. Methods We conducted a retrospective study of adults with positive blood cultures with S maltophilia who received ≥48h of directed antimicrobials at our institution between 3/2013 and 6/2022. Patients were stratified by their antimicrobial treatment, including levofloxacin, SXT, minocycline, ceftazidime, or combination therapy. The primary outcome was 30d all-cause mortality. Secondary outcomes were microbiological and clinical cure. Microbiological failure was defined as blood cultures growing S maltophilia during or within 7d of discontinuing therapy. Clinical failure was defined as a lack of resolution of signs or symptoms of infection requiring therapy adjustment. Results Of 67 patients with positive S maltophilia blood cultures, 53 patients treated with levofloxacin (n = 27), SXT (n = 10), minocycline (n = 8), combination (n = 5) or ceftazidime (n = 3) were included. The remaining 14 patients were excluded for receiving < 48h of therapy. The median Charlson comorbidity index was 4 [IQR 3-6]. The most common source of bacteremia was catheter-related (n = 27). Overall, 30d mortality was 26.4%. There was no significant difference in 30d mortality among patients treated with levofloxacin, SXT, minocycline, combination or ceftazidime (p = 0.23). Interestingly, patients with monomicrobial S maltophilia bacteremia had statistically higher 30d mortality (35.3% versus 11.8%, p < 0.05). Microbiological and clinical cure rates were similar between treatment groups (p = 0.06 and p = 0.16, respectively). Conclusion Treatment options for S maltophilia bacteremia resulted in similar 30d mortality; however, findings were limited by the small sample size. Larger, prospective studies are warranted to detect differences in treatment alternatives. Disclosures All Authors: No reported disclosures

Abstract Background Cefiderocol is a novel siderophore cephalosporin that demonstrated in vitro activity against carbapenem-resistant Enterobacterales, Acinetobacter baumannii (AB), Pseudomonas aeruginosa (PA), and Stenotrophomonas maltophilia. Cefiderocol demonstrated promising efficacy in randomized, clinical trials; however, real-world utilization of cefiderocol is not well characterized. Methods This was a retrospective study of adults who received cefiderocol for ≥72h for serious meropenem-resistant Gram negative infections at our institution between 11/2021 and 12/2022. Patients with all sources of infection were considered for inclusion. Clinical failure was defined as all-cause 90d or in-hospital mortality, or the lack of resolution of signs or symptoms of infection. Microbiological failure was defined as positive cultures growing the index pathogen after ≥7d of initiating therapy or ≤60d of completing therapy. Descriptive statistics were used to compare outcomes by the index pathogen. Results Of 55 patients who received cefiderocol, 35 patients were included. The remaining 20 patients were excluded for receiving < 72h of therapy. The most common infections were pneumonia (n = 17, 48.6%), skin and skin structure infections (n = 6, 17.1%), and osteomyelitis (n = 5, 14.3%) wherein PA (n = 17, 48.6%) and AB (n = 14, 40%) were isolated most frequently. The overall 90d and in-hospital mortality rates were 9 (25.7%) and 11 (31.4%) patients, respectively. Clinical failure, assessed in 34 patients, occurred in 10 (29.4%) patients and was similar between pathogens (p = 0.71). Microbiological failure, assessed in 26 patients, occurred more commonly in infections caused by PA (n = 11/12, 91.7%) compared to all other pathogens (n = 3/14, 21.4%; p < 0.01). Notably, most microbiological failures due to PA were in the setting of pneumonia (n = 6/11, 54.5%). Conclusion Real-world experience demonstrated that most patients receiving cefiderocol for serious Gram-negative infections did well; however, microbiological failure among patients with PA infections may be attributed to the difficulty in differentiating true pathogens and colonizers in respiratory infections. Disclosures All Authors: No reported disclosures

PURPOSE:Stenotrophomonas maltophilia has emerged as a critical opportunistic pathogen associated with significant morbidity and mortality. Tetracycline derivatives have been recognized as alternative treatment options, but they have varied pharmacokinetic properties. An integrated approach to different tetracycline derivatives for formulary decisions is reported.METHODS:The minimum inhibitory concentration (MIC) data from clonally diverse bloodstream S. maltophilia isolates were examined, along with the pharmacokinetic profiles of 4 tetracycline derivatives, to predict achievable pharmacodynamic exposures with standard intravenous dosing regimens. Antimicrobial therapy was assessed using the ratio of daily drug acquisition cost relative to the ratio of the free-drug area under the time-concentration curve (fAUC) to minimum inhibitory concentration (MIC) for 90% of isolates (fAUC/MIC90).RESULTS:In our analysis, minocycline had the greatest fAUC/MIC90. Doxycycline was the most financially preferred agent, as calculated using 2020 average wholesale price for base-case estimates of drug acquisition cost.CONCLUSION:An integrated evaluation for antimicrobial formulary decision-making addressed local susceptibility data, pharmacokinetics, pharmacodynamics, dosing regimens, and drug acquisition costs. This comprehensive method is more objective than the conventional approach and warrants validation.

Abstract Background Ventricular assist devices (VAD) prolong life expectancy or serve as a bridge to heart transplant in end stage heart failure but are not without risks. These patients are at high risk for device-related infections with a propensity for relapse. Indications and efficacy of chronic antimicrobial suppression (CAS) to prevent relapse are not well defined. Methods We conducted a retrospective study of all adult patients with VAD infections at our institution between 1/1/2013 and 10/31/2020. VAD-specific or VAD-related infections were defined by the International Society for Heart and Lung Transplantation criteria. Patients were stratified by receipt of CAS or no CAS after completing index infection treatment. Relapsed infections were defined as those recurred at the same site caused by the same organism seen in the index infection. Time-to-relapse infection was defined as the time in days between the index infection and first relapse. The primary outcome was CAS efficacy measured by time-to-relapse in VAD-specific or -related infections. Results A total of 83 patients were included with a documented VAD-specific (n = 68) or VAD-related (n = 15) infection. Driveline (n = 66) and bloodstream (n = 13) infections were the most common VAD-specific and VAD-related infections, respectively. For the index infection, all patients received antimicrobial treatment and 16.4% required incision and drainage. Staphylococcus aureus was most frequently isolated in 46 cases. Oral minocycline was the most commonly utilized agent in 22 of 47 patients receiving CAS. Agent-specific CAS efficacy was unable to be assessed due to the small sample. In patients who received CAS, 57% experienced a relapse infection compared to 81% in patients not receiving CAS (p = 0.03). The median time to relapse was 151 days (IQR 78-247) and 57 days (IQR 36-114) in the CAS and non-CAS groups, respectively (p < 0.01). Conclusion The incidence of relapse infection in the setting of CAS was lower compared to those not receiving CAS. Patients receiving CAS were relapse-free for a significantly longer duration. Larger studies are warranted to assess if one agent confers a benefit over another. Disclosures M. Rizwan Sohail, MD, Aziyo Biologics: Honoraria|Boston Scientific Corporation: Honoraria|Medtronic: Grant/Research Support|TRYX: Grant/Research Support.

Although all chronic wounds are colonized by microbes and not all wounds are infected, antibiotics are widely prescribed in wound care settings. Antibiotic misuse in wound care occurs for many reasons, including diagnostic uncertainty regarding the presence of a bacterial infection, insufficient clinician knowledge about when antibiotics are necessary, clinicians' fear of achieving unfavorable patient outcomes, and patient demand. Understanding wound infection stages and proper wound assessment are essential to differentiate infected wounds from colonized wounds. Adequate knowledge of microbiology and commonly prescribed antibiotics in wound care settings is critical to optimize antimicrobial management. In this article, the authors review wound infection stages, host resistant factors, and microbial virulence factors that affect the progression of wound infection, specimen collection, common causative organisms, and commonly prescribed antibiotics in wound care settings.

Abstract Background Treatment options against Enterococcus spp., a common nosocomial pathogen, are limited due to intrinsic resistance to multiple antibiotics. Ampicillin is considered drug of choice if susceptible, but data comparing outcomes between ampicillin, daptomycin, and vancomycin for ampicillin-sensitive Enterococcus spp. bacteremia are limited. Methods This was a single-center retrospective cohort study of adults with confirmed ampicillin-sensitive Enterococcus spp. bloodstream infection (BSI) who received definitive treatment with intravenous ampicillin, daptomycin, or vancomycin from January 2013 to December 2021. Polymicrobial BSI were excluded. Definitive treatment was defined as the active antibiotic used for more than 50% of the total treatment duration following availability of susceptibility results. The primary outcome was 28-day all-cause hospital mortality; secondary outcomes were 90-day readmission due to microbiological recurrence and all-cause hospital mortality. Multivariate Cox regression analysis was performed to identify independent risk factors for 28-day hospital mortality. Results A total of 199 patients (ampicillin, n = 141; daptomycin, n = 17; vancomycin, n = 41) were evaluated. Overall in-hospital all-cause mortality was 15.1% (n = 30). Twenty-eight-day hospital mortality was numerically lower with ampicillin and daptomycin compared to vancomycin (9.2%, 11.8%, and 22%, respectively; p = 0.088). Ninety-day readmission due to microbiological recurrence (4.3%, 5.9%, and 7.3%; p = 0.722) and all-cause hospital mortality (12.8%, 17.6%, and 22%; p = 0.335) were not significantly different between treatment groups. Independent risk factors for 28-day hospital mortality included age (hazard ratio [HR] 1.05, 95% confidence interval [CI] 1.02 to 1.09; p = 0.003), E. faecium BSI (HR 3.94, 95% CI 1.39 to 11.1; p = 0.010), and definitive treatment with vancomycin (HR 2.54, 95% CI 1.04 to 6.21; p = 0.040). Conclusion Vancomycin used as definitive therapy for ampicillin-sensitive Enterococcus spp. bacteremia was found to be an independent risk factor for 28-day mortality. Further studies evaluating the role of daptomycin in this setting are warranted. Disclosures All Authors: No reported disclosures.

Abstract Background Sternal wound infections (SWI) are a devastating complication of cardiac surgery. The majority of SWI are bacterial infections; however, Candida species are a less common cause and have not been well described. The purposes of this study were (1) to describe clinical characteristics, management and outcomes of Candida SWI and (2) to compare the risk factors and outcomes for Candida to bacterial SWI. Methods Our study reviewed medical records of 41 patients with Candida SWI after cardiac surgeries between 2013 - 2020 at our medical center, then compared them to 76 patients with bacterial SWI during the same timeframe via univariate analysis. We defined superficial SWI as positive culture isolates involving the skin or subcutaneous tissues, deep SWI as involving deep soft tissues or bone, and mediastinitis as involving the mediastinum. Results Of the 41 Candida SWI patients, relevant comorbidities included previous cardiac surgery (46.3%), heart failure (65.9%), and diabetes (58.5%). Candida SWI was diagnosed at an average of 123.6 days after cardiac surgery, with the majority being deep SWI (70.7%). Candida albicans was most common (70.7%). Bacterial co-infections were found in 53.7% (Table 1). Longer bypass and operative times for the initial cardiac surgery were found to be positively correlated to disease severity. Clinical cure rate after completion of antimicrobial treatment was 100% in superficial SWI, 72.4% in deep SWI and 25.0% in mediastinitis. Overall mortality was 29.3%: 25%, 24.1% and 50.0%, respectively. When compared to bacterial SWI, factors significantly associated with Candida SWI included: previous cardiac surgery (46.3% vs. 7.9%, odds ratio (OR): 5.9; 95% confidence interval (CI): 2.2-15.9), heart failure (65.9% vs. 11.8%, OR: 5.6; 95% CI: 2.4-12.9), and >48 hours of postoperative antibiotics (39.0% vs. 3.0%, OR: 9.9; 95% CI: 2.7-35.9). Mortality rates were higher with Candida than with bacterial infections (29.3% vs. 1.3%, OR: 22.2, 95% CI 2.8-177.2) (Table 2). Conclusion This study showed Candida SWI as a serious complication of extensive cardiac surgery with higher mortality rates. Prior history of cardiac surgery and heart failure, prolonged surgeries, and complicated postoperative course were significant risk factors for the development of Candida SWI. Disclosures Barbara Trautner, MD, PhD, Genetech: Advisor/Consultant.