bluuebunny/crossref_metadata_2025_split huggingface dataset:
1839. Impact of Hypoalbuminemia on Ceftriaxone Treatment Failure in Patients With Enterobacterales Bacteremia
Authors: Steere Evan , Eubank Taryn , Greenlee Sage , Cooper Megan , Drake Ty C 
Published: December 2022

Abstract

Background
Ceftriaxone (CRO) is a third-generation cephalosporin that is commonly prescribed due to its robust Gram-negative activity and lack of renal dose adjustments. It is also highly protein bound allowing for once daily dosing. In patients with hypoalbuminemia, however, the proportion of free drug is increased thus increasing the rate at which CRO is renally eliminated. This increased clearance could lead to lower serum concentrations and increased risk of treatment failure.

Methods
We performed a retrospective, cohort study to assess the impact of hypoalbuminemia (serum albumin ≤ 2.5 g/dL) on treatment failure among patients with monomicrobial Enterobacterales bacteremia. Adult patients who received &gt; 72 hours of CRO therapy for susceptible Enterobacterales bacteremia between May 1, 2016 and April 30, 2021 were eligible for inclusion. The primary outcome of treatment failure was a composite of inpatient mortality or escalation to an intravenous anti-pseudomonal antibiotic or ertapenem. Secondary outcomes included hospital length of stay, total duration of antibiotic therapy, and time to infection resolution. Baseline characteristics and outcomes were compared using R Studio (Version 4.1.0) in a 1:1 propensity-matched cohort.

Results
After propensity score matching, 142 patients were included in each study group. The most common organisms in our cohort were Escherichia coli (71.5%), Klebsiella pneumoniae (14.1%), and Proteus mirabilis (5.3%). The most frequently implicated source of infection was the urinary tract (71.5%). Interestingly, treatment failure was numerically higher in the hypoalbuminemia group but was not statistically significant (12.0% vs. 7.7%, p = 0.23). All secondary outcomes were similar between groups. Among the subgroup of patients admitted to the ICU at baseline, the difference in treatment failure was even greater between patients with hypoalbuminemia and those without (23.3% vs. 7.5%, P = 0.07).

Conclusion
Hypoalbuminemia did not appear to have a significant impact on clinical outcomes among patients with Enterobacterales bacteremia treated with CRO. However, critically ill patients may be subject to higher incidence of treatment failure in the presence of hypoalbuminemia.

Disclosures
All Authors: No reported disclosures.
2315. Impact of MSSA Surveillance and Decolonization on Invasive Infection in the Neonatal ICU
Authors: Reich Patrick J , Ikpeama Geoffrey , Niesen Angela , Liviskie Caren , McPherson Christopher , Fritz Stephanie A 
Published: December 2022

Abstract

Background
Invasive methicillin-susceptible Staphylococcus aureus (MSSA) infections are an important cause of morbidity and mortality in neonatal intensive care unit (NICU) infants. MSSA colonization (asymptomatic carriage in the nose, skin, or gut) is a risk factor for subsequent invasive infection (e.g., pneumonia, bone infections, bloodstream infections, etc). Active surveillance programs coupled with decolonization measures for MSSA-colonized infants have been associated with decreased invasive MSSA infection rates in the NICU setting.

Methods
In June 2020, an active surveillance program was implemented to detect MSSA nasal colonization for infants admitted to the St. Louis Children’s Hospital NICU, a 140-bed quaternary NICU. MSSA-colonized infants were decolonized with a 7 day course of intranasal mupirocin twice daily plus topical chlorhexidine baths on days 1, 4, and 7 (for infants greater than 30 weeks postmenstrual age). MSSA bloodstream infection (BSI) rates were followed quarterly pre- (September 2018-May 2020) and post- (June 2020-March 2022) implementation of MSSA surveillance and decolonization. Mean MSSA BSI rates pre- and post-implementation were compared via paired T-test. The number of infants treated with mupirocin was calculated pre- and post-implementation.

Results
After implementing MSSA surveillance and decolonization there was no significant change in the mean MSSA BSI rate (Figure): 0.22 per 1000 patient-days pre-implementation, 0.16 per 1000 patient-days post-implementation (p=0.37). Since initiating MSSA decolonization in June 2020, the number of NICU infants exposed to mupirocin increased nearly fourfold: mean 10 infants treated per month pre-implementation, mean 38 infants treated per month post-implementation.

Conclusion
Implementing an MSSA surveillance and decolonization program in the NICU was not associated with a sustained decrease in invasive MSSA infections. However, mupirocin use in the NICU nearly quadrupled following implementation. Additional investigation is warranted to identify potential contributing factors for unchanged invasive MSSA infection rates despite active surveillance and decolonization (e.g., emerging mupirocin resistance).

Disclosures
All Authors: No reported disclosures.
1845. Oritavancin Compared to the Standard-of-Care for the Treatment of Gram-positive Blood Stream Infections
Authors: Moenster Ryan P , Wallace-Lacey Ashleigh , Lorenz Michael , Skouby Danielle , Fong Rebecca , Abdulbasir Anosha , Abner Hartley , Alberts Justin , Doty Johnathan , Tiefenauer Seth , Western Hannah , Linneman Travis W 
Published: December 2022

Abstract

Background
Data is limited comparing oritavancin (ORT) to the standard-of-care (SOC) for the treatment gram-positive blood stream infections (BSI).

Methods
This was a retrospective study of all patients in the Veteran’s Affairs Health Care System treated with at least 1 dose of oritavancin or at least 5 days of vancomycin, daptomycin, ceftaroline, ampicillin, ampicillin-sulbactam, nafcillin, oxacillin, or cefazolin for a documented gram-positive BSI from 1 January 2015 to 30 June 2021. Patients with polymicrobial blood cultures or positive cultures from other sites were included if the organisms were sensitive to the incident antimicrobial; no concomitant antimicrobials could be used once the incident agent was started. Individuals were also excluded if they were diagnosed with endocarditis, had a neutrophil count &lt; 500 cells/mm3, or had a diagnosis of Human Immunodeficiency Virus (HIV) on their problem list.
The primary composite outcome was clinical failure, defined as all-cause mortality within 30-days from the end of therapy, or blood cultures positive for the incident organisms ≥72 hours after administration of the first dose and ≤30 days after the administration of the final dose of the study antimicrobial, or any drug or line-related readmissions within 30-days of hospital discharge. Secondary outcomes included all-cause 30-day readmission and rates of acute kidney injury (AKI).

Results
Two hundred-forty patients were identified for screening with 96 meeting criteria (27 in ORT and 69 in SOC groups). Baseline characteristics were generally balanced between groups except more patients in the ORT group received &gt; 96-hours of treatment before the incident antimicrobial was started (70.3% (19/27) vs. 13.04% (9/69); p&lt;0.001). The pathogen most prevalent was methicillin-susceptible Staphylococcus aureus (MSSA) (ORT 33.3% (9/27) vs. SOC 46.4% (32/69)). Clinical failure occurred in 7.4% (2/27) in the ORT group and 17.4% (12/69) in SOC (p=0.34). No components of the primary outcome were significantly different between groups, but AKI did occur more commonly in the SOC group (27.5% (19/69) vs. 3.7% (1/27); p=0.01).

Conclusion
ORT appears to be a safe and effective option when directly compared to the SOC for non-endocarditis BSIs.

Disclosures
Ryan P. Moenster, Pharm.D., FIDSA, Melinta Therapeutics: Grant/Research Support|Melinta Therapeutics: Honoraria.
1848. Predictors of 6-Month Mortality in Staphylococcus aureus Bacteremia: A Population-Based Study in Olmsted County, Minnesota, from 2006 to 2020
Authors: Hindy Joya-Rita , Quintero-martinez Juan A , Lahr Brian D , DeSimone Daniel C , Baddour Larry M 
Published: December 2022

Abstract

Background
Staphylococcus aureus has high mortality rates, which is influenced by several factors related to the host-pathogen interaction. The current study aims to provide a contemporary evaluation of predictors of 6-month mortality rate in a population-based cohort of incident Staphylococcus aureus bacteremia (SAB) cases.

Methods
Retrospective population-based study of 541 adult residents of Olmsted County, MN with monomicrobial SAB from January 1, 2006 through December 31, 2020. The study’s primary outcome was 6-month mortality rate, and a survival analysis was prepared by the Kaplan-Meier method. Multivariable Cox regression was used to investigate risk factors associated with 6-month mortality.

Results
The median (IQR) age of 541 patients with SAB was 66.8 (54.4-78.5) years and 39.6% were female. The median Charlson Comorbidity Index (CCI) was 2 (1-4). SAB cases were healthcare-associated in 49.2% and 56.2% were methicillin-susceptible. Twenty percent of SAB cases had an unknown infection source and 38.3% had complicated bacteremia. There were 7 relapses within the first 12 weeks of follow-up, corresponding to a cumulative incidence rate of 1.3%. There were no re-infections through the remainder of the 6-month follow-up, although there were 2 recurrences after 7 months. Eighty-nine (16.5%) patients died within 1 month of SAB diagnosis and 144 (26.7%) patients died during the 6-month follow-up period. In a multivariable analysis, older age, elevated CCI, unknown source of SAB, and intensive care unit (ICU) admission were significant predictors of an increased 6-month mortality rate. In contrast, presence of diabetes mellitus was significantly associated with a decreased 6-month mortality rate; also, undergoing infectious diseases consultation was associated with reduced mortality in the first 2 weeks, but not for the remainder of the 6-month follow-up period.

Conclusion
To our knowledge, the current investigation represents the only contemporary population-based study determining significant predictors of mortality in SAB patients, namely, older age, higher CCI, unknown source of SAB, and ICU admission. This study also described one of the lowest 30-day mortality rates reported over the past 2 decades. Figure 1.Survival and reinfection rates of patients with SAB over 6 months.
Abbreviations: SAB, Staphylococcus aureus bacteremia.
Foot notes: The overall survival curve was derived by the Kaplan-Meier estimator, while the curve for reinfection was estimated by the cumulative incidence function taking into account the competing risk of death.

Disclosures
Larry M. Baddour, M.D., Boston Scientific: Advisor/Consultant|Botanix Pharmaceuticals: Advisor/Consultant|Roivant Sciences: Advisor/Consultant|UpToDate, Inc.: Royalty payments - authorship duties.
1853. Relevance of Actinomyces Bacteremia
Authors: Sharma Mamta , Arcobello Jonathan T , Tanveer Farah , Revankar Sanjay , Bhargava Asish 
Published: December 2022

Abstract

Background
Actinomyces species are Gram-positive anaerobic bacilli colonizing the human oropharynx, gastrointestinal tract, and urogenital tract asso­ciated with a wide range of infections. The isolation of Actinomyces spp. from sterile clinical samples is regarded as significant. We reviewed the risk factors, clinical features, and outcomes in patients with Actinomyces bacteremia.

Methods
We conducted a retrospective study of all inpatients with Actinomyces bacteremia from two tertiary care centers from 1/1/06 -9 /26/19 . Data were collected on demographic and clinical characteristics, co-morbidities, primary source of infection, treatment received and duration of therapy and outcomes. True bacteremia was defined as Actinomyces bacteremia with systemic manifestations of infection.

Results
A total of 82 cases of positive blood cultures were identified of which 33 were true bacteremia, based on clinical criteria among 19 females and 14 males ranging from 19-93 years (63.8 ±19.5). Majority of patients were blacks (70%). Clinical risk factors predominantly were diabetes mellitus (21%), chronic renal failure (18%) and active malignancy (12%). Majority of blood cultures were positive within 48 hrs. of admission 84.8%. Skin and soft tissue (27%) was the most common source followed by respiratory (15%), intrabdominal (15%), osteomyelitis (12%), odontogenic (6%), endovascular (6%) genitourinary (3%) and unknown source (16%). In 27 (81%) cases, bacteremia was isolated to species level: A.meyeri 8 (30%), A.odontolyticus 7 (26%), A.israelli 7 (26%), A.turicensis 4 (15%) and A.neuii 1 (4%). The infectious diseases service was consulted in 20 cases of true bacteremia. Duration of antibiotics ranged between 0-84 days (17.6 ±20.7). All-cause mortality during hospitalization was 24% (8).

Conclusion
Not all Actinomyces bacteremia may be relevant and can represent transient bacteremia. Better awareness and involvement of infectious disease service is recommended in understanding of the clinical significance, to ensure appropriate therapy for patients thereby implementing antibiotic stewardship to improve antibiotic use and, patient safety and improve outcomes. Further research will help to identify the true significance of these isolates.

Disclosures
All Authors: No reported disclosures.
1862. Time to Therapeutic Goal is Faster with Continuous Infusion Vancomycin for Methicillin-Resistant Staphylococcus aureus Bloodstream Infections
Authors: Gilliam Diari , Acosta Dominic , Carvour Martha , Walraven Carla 
Published: December 2022

Abstract

Background
Continuous infusion vancomycin (CIV) is an attractive alternative to intermittent infusion vancomycin (IIV) as it may result in more rapid attainment of target serum drug concentrations, provide ease of monitoring, and decreased risk of nephrotoxicity. At our institution CIV has been the preferred infusion method for over 20 years. The purpose of this study was to examine the time to therapeutic goal among patients receiving IIV compared to CIV for methicillin-resistant Staphylococcus aureus (MRSA) bacteremia. Secondary objectives included all-cause readmission, relapse, and mortality 30 days after completion of therapy.

Methods
This was a single-center, retrospective study of patients who received vancomycin for MRSA bacteremia between January 2018 and December 2021. Included patients were ≥ 18 years of age, had ≥ 1 blood culture positive for MRSA, received vancomycin for &gt; 10 days, and had follow-up in the outpatient parenteral antimicrobial therapy clinic. Patients who were pregnant, received vancomycin for ≤ 10 days, or were diagnosed at an outside hospital were excluded. All patients were started on IIV then transitioned to CIV. Patients on IIV with an appropriately drawn trough between 15-20 mcg/mL were considered therapeutic. For patients on CIV, a single random level between 17-25 mcg/mL, corresponding to an AUC/MIC of 400-600 mcg·h/mL, was considered therapeutic.

Results
Sixty-three patients with 65 MRSA bacteremia episodes were included. Significantly fewer patients achieved a therapeutic goal on IIV compared to patients on CIV (52.3% vs. 83.1%, p-value &lt; 0.01). Of the 31 patients who did not reach the IIV trough goal, 87.1% became therapeutic when switched to CIV. Patients on IIV took 3.6 days, on average, to reach the target goal, compared to 1.9 days when patients were switched to CIV (95% confidence interval 0.50 – 2.96, p-value &lt; 0.01). No patients experienced relapse or mortality 30 days after completion of therapy. Six patients (9.2%) were readmitted 30 days after completion of therapy.

Conclusion
CIV enabled patients with MRSA bacteremia to achieve the AUC/MIC goal significantly faster than when receiving IIV. Patients who were unable to achieve a therapeutic goal on IIV became therapeutic once switched to CIV.

Disclosures
Martha Carvour, MD, PhD, The Suga Project/The Suga Project Foundation: I provide consultation and support but do not receive compensation.
1863. Treatment and Outcomes of Cefoxitin-Non-Susceptible Serratia marcescens, Klebsiella aerogenes, Citrobacter freundii, Enterobacter cloacae, and Morganella morganii Bacteremia with Piperacillin/Tazobactam Versus Cefepime or Carbapenem in Immunocompromised Patients
Authors: Lu Brian , Wong Miranda , Diep Calvin , Ha David R , Bounthavong Mark , Banaei Niaz , Deresinski Stan 
Published: December 2022

Abstract

Background
A recent guidance suggested “caution if prescribing piperacillin-tazobactam for serious infections caused by organisms at high risk of significant AmpC production” and that the preferred antibiotic choice should be either cefepime or a carbapenem, despite an admitted lack of definitive evidence. Examination of this question in immunocompromised patients may provide such evidence.

Methods
This was a retrospective, single-center study conducted from January 2016 to December 2021. We included immunocompromised patients aged 18 years or older who had a laboratory confirmed blood culture positive for Enterobacterales showing non-susceptibility to cefoxitin and were definitively treated with piperacillin-tazobactam, cefepime, or a carbapenem. The primary endpoint was a composite of clinical or microbiological failure, which was comprised of in-hospital 30-day mortality, white blood count &gt;12 x 109/L or temperature &gt;38°C on days 5-7, microbiological failure on days 3-5, or microbiological recurrence/relapse on days 5-30.

Results
We identified 81 patients who were included for analysis. Baseline characteristics between arms were similar between groups except for more frequent severe neutropenia (p=0.010) and higher Pitt bacteremia scores (p=0.042) in the cefepime/carbapenem group. Within the piperacillin/tazobactam arm, 17 of 35 (48.6%) had clinical or microbiological failure, compared to 17 of 46 (37.0%) patients in the carbapenem/cefepime arm (p=0.294). Microbiological failure occurred in 4 of 35 (11.4%) patients treated with piperacillin/tazobactam compared to 0 of 46 (0%) patients treated with a carbapenem/cefepime (p=0.019). In multivariate analysis, patients treated with a carbapenem/cefepime had a 69% lower odds of clinical or microbiological failure compared to those treated with piperacillin/tazobactam (OR = 0.31; 95% confidence interval, 0.10-0.98).

Conclusion
In immunocompromised patients with bacteremia due to cefoxitin-non-susceptible Serratia marcescens, Klebsiella aerogenes, Citrobacter freundii, Enterobacter cloacae, or Morganella morganii, definitive treatment with piperacillin/tazobactam was associated with a higher likelihood of microbiological failure compared with treatment with a carbapenem or cefepime.

Disclosures
All Authors: No reported disclosures.
1865. Analysis of National Surveillance Data to Support Case Definition Revisions for Multisystem Inflammatory Syndrome in Children (MIS-C), United States, February 2020–April 2022
Authors: Campbell Angela P , Miller Allison D , Yousaf Anna R , Lee Ellen H , Lim Sarah , Brown Catherine M , Oster Matthew , Abrams Joseph , Lindsey Katherine , Wu Michael J , Cato Shana Godfred , Ermias Belay , Zambrano Laura D , Melgar Michael 
Published: December 2022

Abstract

Background
Classification of MIS-C, COVID-19, and other pediatric inflammatory conditions is challenged by phenotypic overlap and absence of diagnostic laboratory evidence. Due to public health need and based on limited data from early cases, CDC developed a necessarily broad MIS-C surveillance case definition in May 2020. Studies have since shown that some criteria do not distinguish between MIS-C and other conditions and may contribute to misclassification. To inform planned revision to the CDC definition, we evaluated the impact of narrowing these criteria on case inclusion in national MIS-C surveillance.

Methods
Of state and local health-department reported cases meeting the current MIS-C case definition as of 04/14/2022, we describe the proportion that met revised criteria under consideration including fever duration, C-reactive protein (CRP) elevation using a defined cutoff, and organ involvement represented by specific criteria. We also evaluated cases identified using potential combinations of revised criteria.

Results
Of 8,096 MIS-C cases fulfilling the original case definition, 6,332 (78%) had sufficient data for evaluation of criteria. Of these, 96% had fever for ≥2 days and 94% had a CRP ≥ 3.0 mg/dL (Table 1). Cardiac involvement defined by key features of MIS-C was present in 84% of cases (62% if BNP/proBNP elevation was excluded); 43% had shock. Dermatologic, gastrointestinal (GI) and hematologic involvement were present in 75%, 89% and 37% of cases, respectively. Neurologic (excluding headache), renal, and respiratory involvement were present in 16%, 20%, and 63% of cases, respectively. The number of cases with ≥ 2 of cardiac (without BNP/proBNP elevation), shock, dermatologic, GI, or hematologic involvement was 5,733 (91%). SARS-CoV-2 testing results are shown in Table 2.

Conclusion
The CDC MIS-C case definition is intentionally broad. Using national surveillance data, we evaluated case inclusion under narrower criteria, prioritizing features of MIS-C that distinguish it from similar pediatric inflammatory conditions. A surveillance case definition may not capture all cases and is not intended to replace clinical judgment. We plan to assess additional criteria combinations, describe potentially excluded cases, and incorporate findings into a revised definition.

Disclosures
All Authors: No reported disclosures.
1875. Continued demographic shifts in hospitalised COVID-19 patients from migrant workers to a vulnerable and more elderly local population at risk of severe disease
Authors: Nicholas Ngiam Jinghao , Chhabra Srishti , Goh Wilson , Sim Meng Ying , Liong Tze Sian , Chew Nicholas W S , Sia Ching Hui , Cross Gail Brenda , Tambyah Paul Anantharajah 
Published: December 2022

Abstract

Background
In the early months of the COVID-19 pandemic, the vast majority of infected persons were migrant workers living in dormitories who were young and with few medical co-morbidities. In 2021, this shifted to the more vulnerable and elderly population within the local community. We examined trends amongst the hospitalised cases, in order to demonstrate changes in disease severity in association with the evolving demographics.
Demographic shifts in hospitalised patients with COVID-19.
Proportion of hospitalised patients with COVID-19 requiring intensive care over time in Singapore

Methods
All patients with PCR-positive SARS-CoV-2 admitted from February 2020 to October 2021 were included, and subsequently stratified by their year of admission (2020 or 2021). Demographics were also classified by sex, ethnicity, as well as mode of transmission, namely i) imported cases, ii) locally-transmitted cases outside of migrant worker dormitories, and iii) migrant worker dormitory cases. We compared the baseline clinical characteristics, clinical presentation and outcomes.

Results
A majority of cases were seen in 2020 (n=1359), compared with 2021 (n=422), due to the large outbreaks in migrant worker dormitories. Nevertheless, the greater proportion of locally-transmitted cases outside of dormitories in 2021 (78.7% vs 12.3%) compared with 2020 meant a significantly older population with more medical co-morbidities were exposed to COVID-19. This led to an observably higher proportion of patients with severe disease, presenting with raised inflammatory markers, need for therapeutics, supplemental oxygenation and higher mortality.
Baseline characteristics of hospitalised patients with COVID-19 in Singapore over time.

Conclusion
Changing demographics and the characteristics of the exposed populations are associated with distinct differences in clinical presentation and outcomes. Understanding demographic shifts may be crucial in appropriate allocation of healthcare resources in managing hospitalised patients with COVID-19.

Disclosures
All Authors: No reported disclosures.