bluuebunny/crossref_metadata_2025_split huggingface dataset:
1817. Characteristics and Outcomes in Patients with Staphylococcus lugdunensis Bacteremia Compared with Staphylococcus aureus and Staphylococcus epidermidis Bacteremia
Authors: Yukawa Satomi , Noguchi Taro , Shinohara Koh , Tsuchido Yasuhiro , Yamamoto Masaki , Matsumura Yasufumi , Nagao Miki 
Published: December 2022

Abstract

Background
Staphyococcus lugudnensis (SL) is a coagulase negative Staphylococcus species with a potential to cause invasive infection. Few studies have evaluated characteristics and outcomes of SL bacteremia (SLB) compared with Staphylococcus aureus (SA) and Staphylococcus epidermidis (SE).

Methods
We performed a single center retrospective case-control study of patients &gt; =18 years of age with SLB with at least two sets of positive blood cultures at Kyoto University Hospital, Japan from January 2005 to December 2021. Patients who had SA bacteremia (SAB) with at least one set of positive blood culture and those who had SE bacteremia (SEB) with at least two sets of positive blood cultures were randomly selected in a 1:5:5 (SL:SA:SE) ratio during the same period. Characteristics and clinical outcomes of SLB were compared with those of SAB and SEB.

Results
A total of 24 patients with SLB, 120 patients with SAB, and 120 patients with SEB were included. Patients’ median age (interquartile range) was 69 (60, 75), 68 (49, 77) and 65 (51, 73) in order of SL, SA, and SE. The rate of hospital-acquired infection in SL was similar to that of SA (54% vs 64%; p=0.86), lower than that of SE (54% vs 91%; p&lt; 0.01). Rates of methicillin resistance and intravascular catheterization were higher in SE (83% and 92%, respectively). Patients with SLB were more likely to be on hemodialysis (25%). Rates of polymicrobial bacteremia and blood cancer was lower in SA (7% and 8%, respectively). Echocardiography was done for 14 patients in SL, lower than in SA (58% vs 82%; p=0.01). The rate of infective endocarditis (IE) (primary and secondary) was not significantly different among three groups (SL 8.5%, SA 6.5%, SE 2%). There was no significant difference in rate of metastatic lesions between SL and SA (17% vs 20%, p=0.9), statically lower in SE than in SL (17% vs 4%; p&lt; 0.01). Seven-day mortality was similar between SL and SA (8% vs 7%; p=0.77), lower in SE than in SL (8% vs 0.5%; p=0.02). Thirty-day mortality in SL was not significantly different in other groups (SL 17%, SA 18%, SE 10%).

Conclusion
The rates of metastatic lesions and 7-day mortality in SL were similar to that of SA, higher than that of SE. Appropriate evaluation and treatment that are recommended for SAB may be warranted for patients with SLB.

Disclosures
All Authors: No reported disclosures.
1826. Comparative Use of Vancomycin versus Ampicillin for Blood Stream Infections Caused by Ampicillin-susceptible Enterococcus faecalis
Authors: Phan Michaele , Meredith Jacqueline , Ackley Renee , Ebeid Alex , Goodrich Kristen , Sampson Mindy 
Published: December 2022

Abstract

Background
Available studies assessing the efficacy of beta-lactam antibiotics compared to vancomycin (VAN) in the treatment of Enterococcal blood stream infections (BSI) have varying results and have not assessed the impact of rapid diagnostic testing. We aimed to compare clinical outcomes of ampicillin (AMP) vs. VAN for E. faecalis BSI treatment.

Methods
A multisite, retrospective evaluation of adults with E. faecalis BSI between 2017 to 2021 was performed. Patients who received at least four days of AMP or VAN as definitive therapy were analyzed; only initial episodes were included. All positive blood cultures underwent multiplex polymerase chain reaction blood culture identification (BCID). Patients with polymicrobial BSI were excluded, or if they received ≥ 50% concomitant use of AMP and VAN. The primary outcome was 30-day all-cause mortality. Secondary objectives included 90-day all-cause mortality, hospital length of stay, incidence of treatment failure, persistent BSI, change from initial definitive therapy, and adverse drug reactions (ADRs). Other microbiology endpoints included time to active treatment, BCID, beta-lactam coverage, definitive therapy, and culture clearance. A sample size of 208 patients was estimated to provide a 15% mortality difference with 80% power.

Results
In total, 123 patients with E. faecalis BSI were analyzed (AMP, n = 92; VAN, n = 31). Baseline characteristics were similar among both groups except gender and baseline penicillin allergy (p &lt; 0.001) (Table 1). All-cause 30-day mortality was not significantly different between patients treated with AMP and VAN (10.8% vs. 22.6%, p = 0.130). No difference was found in secondary objectives except time to definitive therapy was longer for the AMP treatment arm (56.7 hours vs. 15.8 hours, p &lt; 0.001) (Table 2). The incidence of ADRs were similar between the two groups (Table 3).

Conclusion
No difference in mortality was observed in the treatment with AMP or VAN for patients with E. faecalis BSI, but the study was not sufficiently powered. Despite the use of rapid BCID testing, earlier initiation of AMP was not observed. AMP or VAN may be reasonable options for treatment of E. faecalis BSI, but further research is warranted.

Disclosures
All Authors: No reported disclosures.
1833. Evaluating the Impact of Reported Beta-Lactam Allergies on Clinical Outcomes in Gram-Negative Bloodstream Infections: A Retrospective Cohort Study
Authors: Uzoma Joy , Patel Sonal , Athans Vasilios , Binkley Shawn , Degnan Kathleen , Dutcher Lauren , Hamilton Keith W , Lee Tiffany , Saw Steve 
Published: December 2022

Abstract

Background
Approximately 15% of hospitalized patients are labeled as beta-lactam (BL) allergic. Despite this, it is estimated that &gt; 90% of patients do not have clinically significant hypersensitivity reactions and are BL-tolerant. The BL allergy label is associated with a host of downstream consequences, including receipt of suboptimal antibiotic therapy, healthcare-associated infections, and bacterial resistance. There are limited data investigating the impact of this allergy label on clinical outcomes in bloodstream infections caused by Gram-negative pathogens (GN-BSI).

Methods
This was a retrospective, single center, cohort study evaluating the impact of BL allergies on clinical outcomes in patients with GN-BSI from January 2017 to August 2021. Adult inpatients with index blood cultures positive for Pseudomonas species or Enterobacterales who received intravenous antibiotics with Gram-negative activity were included. The primary endpoint was time to effective therapy (defined as treatment with in vitro activity against a causative pathogen, as determined by phenotypic susceptibilities) and the key secondary endpoint was 30-day all-cause mortality.

Results
Overall, 120 patients were included, representing 30 BL-allergic (BL-A) and 90 BL-non-allergic (BL-NA) patients. Blood cultures positive for Pseudomonas species or Enterobacterales were evenly distributed (Table 1). Among Enterobacterales, Escherichia coli was implicated in 25% of cases overall. The most common source of infection was intra-abdominal infection. Across groups, median quick Pitt Bacteremia Score was 1 (IQR 0-2). Infectious Diseases was consulted in 37% of BL-A patients vs. 29% of BL-NA patients. Of BL allergies reported, 86% were classified as likely immunoglobulin E (IgE) mediated reactions. Allergy was not consulted in any of these cases. Median time to effective therapy was 162 minutes (IQR 20-824 minutes) vs. 103 minutes (IQR 27-775 minutes) in the BL-A and BL-NA groups, respectively. Thirty-day mortality occurred in 31% of BL-A and 21% of BL-NA patients.

Conclusion
Increased time to effective therapy and mortality rates were observed among patients with reported BL allergies. These findings highlight the importance of allergy clarification in antibiotic stewardship.

Disclosures
Kathleen Degnan, MD, Gilead: Grant/Research Support.
1844. Mortality associated with Stenotrophomonas maltophilia bloodstream infection in patients with leukemia
Authors: Aitken Samuel L , Rudoni Joslyn , Marx Kayleigh R , Tverdek Frank P , Shelburne Samuel A , Okhuysen Pablo C 
Published: December 2022

Abstract

Background
Patients with leukemia are disproportionately vulnerable to infections caused by S. maltophilia and mortality approaches 100% in patients with hemorrhagic pneumonia. Trimethoprim-sulfamethoxazole (SXT) is the drug of choice for treatment of infections caused by S. maltophilia however allergies, toxicity, and resistance may preclude its use. We sought to characterize clinical outcomes of patients with leukemia and S. maltophilia bloodstream infection (BSI).

Methods
Patients with leukemia are disproportionately vulnerable to infections caused by S. maltophilia and mortality approaches 100% in patients with hemorrhagic pneumonia. Trimethoprim-sulfamethoxazole (SXT) is the drug of choice for treatment of infections caused by S. maltophilia however allergies, toxicity, and resistance may preclude its use. We sought to characterize clinical outcomes of patients with leukemia and S. maltophilia bloodstream infection (BSI).

Results
Ninety-six patients with leukemia and S. maltophilia BSI were identified. The most common diagnosis was acute myeloid leukemia (60%); 31% had prior stem cell transplant. The most common single identified source was respiratory (31%) followed by central venous catheter (CVC, 26%). A single clear source was unable to be identified in 33%.Overall 14-day mortality was 31%. After excluding eleven patients who died within 24 hours, most patients received SXT (72%), followed by ceftazidime (40%), tigecycline (TGC, 40%), and minocycline (26%). SXT was associated with reduced mortality (hazard ratio [HR] 0.15, 95% confidence interval [CI] 0.05 – 0.44, p &lt; 0.01) while TGC was associated with increased mortality (HR 3.13, 95% CI 1.00 – 9.73, p = 0.05). All patients who died were neutropenic at baseline and none had a CVC infection.

Conclusion
S. maltophilia BSI is associated with high mortality in patients with leukemia, particularly those with neutropenia at baseline. CVC infection alone was not associated with mortality. SXT is associated with reduced mortality relative to other antimicrobials. Alternative agents should be used with caution in these vulnerable patients.

Disclosures
Samuel L. Aitken, PharmD, MPH, Entasis Therapeutics: Advisor/Consultant|GlaxoSmithKline: Advisor/Consultant|Melinta: Grant/Research Support|Shionogi: Advisor/Consultant Pablo C. Okhuysen, MD, AstraZeneca: Stocks/Bonds|Beam Therapeutics: Stocks/Bonds|Biontech: Stocks/Bonds|Deinove: Grant/Research Support|Ferring: Advisor/Consultant|Glaxo Smith Kleine: Stocks/Bonds|Johnson and Johnson: Stocks/Bonds|Melinta: Grant/Research Support|Merck Sharp & Dohme Corp: Grant/Research Support|Moderna: Stocks/Bonds|Napo Pharmaceuticals: Advisor/Consultant|Napo Pharmaceuticals: Grant/Research Support|Novavax: Stocks/Bonds|Pfizer: Stocks/Bonds|Summit: Advisor/Consultant|Summit: Grant/Research Support.
1846. Outcomes in Intravenous to Oral Antimicrobial Therapy in Beta-Streptococcus Species
Authors: Keintz Mackenzie R , Torres Cristina J , Miller Molly M , Alexander Bryan T , Lyden Elizabeth , Lyden Elizabeth , Lyden Elizabeth , Ma Jihyun , Van Schooneveld Trevor C , Marcelin Jasmine R 
Published: December 2022

Abstract

Background
Uncomplicated bloodstream infections (uBSI) are common and often receive prolonged courses of intravenous (IV) antibiotics, increasing risk for catheter-associated complications and hospitalization costs. β-hemolytic Streptococcus spp. are a common cause of BSI and have reliable susceptibility to many oral antibiotics. Clinically improving patients without persistent BSI and a controlled source of infection are candidates for oral antimicrobial therapy (OAT) but despite anecdotal practice, there are few studies affirming the practice of OAT for gram-positive uBSI. We evaluated IV to OAT transitions for treating β-hemolytic streptococcal uBSI.

Methods
This retrospective cohort study included patients &gt;18 years old hospitalized between 1/1/2013 and 12/31/2019 diagnosed with uBSI due to β-hemolytic Streptococcus. Patients were excluded if BSI was due to endovascular, central nervous, or bone/joint infection without source control. We compared outcomes in patients treated with IV only to those transitioned to OAT including: 30-day mortality, antimicrobial therapy, BSI relapse, 30-day rehospitalization, adverse drug events, and reversion to IV therapy. Fisher’s exact test was used for categorical variables; Mann-Whitney test and independent t-test for continuous variables.

Results
A total of 238 Streptococcus BSI (of 321 BSI screened) were included (83 excluded as complicated, pediatric, or outpatient). OAT was used in 153 (64%). Cohort demographics were similar (table 1). Infectious disease (ID) consultation was not statistically associated with OAT transition; in fact, ID consults tended to use less OAT (66% IV vs. 54% OAT p=0.10). Hospital length of stay was statistically shortened in the OAT cohort with a median of 5 (interquartile range 4) vs. 7.5 (10.5) (p&lt; 0.0001). Patients transitioned to OAT were more likely to finish their antibiotic course outpatient (93 vs. 61% p&lt; 0.001). Thirty-day mortality was decreased in the OAT cohort (2% vs. 13% p&lt; 0.0001). Adverse events were not statistically significant between the groups.

Conclusion
Opportunities exist to modify practice management of uBSI. For β-hemolytic Streptococcus uBSI, OAT was associated with decreased length of stay without adverse clinical outcomes.

Disclosures
Bryan T. Alexander, PharmD, BCIDP, AAHIVP, Astellas Pharma: Advisor/Consultant Trevor C. Van Schooneveld, MD, bioMerieux: Advisor/Consultant|bioMerieux: Grant/Research Support|Insmed: Grant/Research Support|Merck: Grant/Research Support|Thermo-Fischer: Advisor/Consultant Jasmine R. Marcelin, MD, Pfizer (Grant reviewer): Honoraria.
1847. Overview of Infective Endocarditis in Patients with Enterococcus Bacteremia from National Standpoint
Authors: Patel Premalkumar M , Ostran Garrett Van , Camps Nicholas 
Published: December 2022

Abstract

Background
Enterococci are the third most common hospital-acquired infection responsible for high morbidity and mortality, and are associated with high-grade vascular infections like infective endocarditis (IE). Our objective of the study is to discuss the outcomes of IE among patients with Enterococcus Bacteremia (EB) using ICD-10 CM codes from the national database.

Methods
We conducted a retrospective cohort study using the publicly accessible National Inpatient Sample (NIS) database from October 2015 to December 2017. Adult patients ( &gt;/=18), who developed EB were included in the study. SAS 9.4 was used for univariate and multivariate logistic regression analyses.

Results
There were a total of 75,465 patients included in the study who developed EB, among them 5440 (7.21%) patients with IE. In this cohort, 3,620 were males and 1,820 females, among them 3,955 (68.2%) were Caucasians, 620 (11.7%) were African Americans, 6,445 (8.80%) were Hispanic, 100 (1.9%) were Asian and 285 (5.4 %) were native Americans with IE. The majority of them were suffering from congestive heart failure (39.0%), valvular disease (22.0%), peripheral vascular disease (14.8%), chronic lung disease (16%) neurological complications (9.2%), diabetes mellitus with complications (13%) renal failure (32%), obesity (11.0%), and/or drug abuse (8%). In-hospital mortality was 13.7% (p&lt; 0.0001), which was most likely due to the underlying co-morbidities, with an average length of stay of 15.8 (7-18) days and an economic burden of 48,850.3 (16,104–54,410) USD in comparison to patients without IE, who had in-hospital mortality 10.9%, average length of stay 13.6 (5-15) days, and economic burden 49,638 (11009-36665) USD. Age-adjusted mortality among the patients with Infective Endocarditis was 1.2 (1.07-1.28).

Conclusion
Based on the results from our study, we found that patients with enterococcus bacteremia in appropriate settings should be screened for infective endocarditis to decrease the in-hospital mortality, length of stay, and economic burden.

Disclosures
All Authors: No reported disclosures.
1850. Purpura Fulminans and Invasive Streptococcus pneumoniae in Immunocompetent individual
Authors: Perwez Talha , Zeineddine Nabil , Farooq Junaid , Duremala F N U , Khan Abrar 
Published: December 2022

Abstract

Background
Purpura Fulminans (PF) associated with invasive Streptococcus pneumoniae (ISP) is extremely rare. We present a case of PF associated with ISP in an immunocompetent person.

Methods
45-year-old male previously healthy, presented with fall, and dizziness for 1 day, preceded by bloody bowel movements and abdominal pain. On arrival to ED, he had shortness of breath, chest tightness and headache. He had a temperature of 101.7 F, HR 128 BPM, RR 37 BPM, and SpO2 94% RA. He had coarse breath sounds bilaterally, petechial and purpuric rash on chest, lips, bilateral upper and lower extremities. Laboratory findings were significant for WBC 39.3 10*3/uL, Hemoglobin 9.3 g/dL, platelets 33 10*3/uL, creatinine 2.8 mg/dl, AST 523, ALT 242, total bilirubin 3.2 with direct 1.5. INR was 2.86, PT 28.9, PTT 57.2, D dimer &gt;20, and fibrinogen 175. CK was 16,295, ferritin 5294, and LDH 1749. Blood smear revealed schistocytes. Blood cultures grew Streptococcus pneumoniae. He was found to be in DIC, with multi organ failure. Over the course of stay he required O2 support with HFNC of 30 L/min. CT chest showed bilateral ground glass opacities. CT A/P was unremarkable. Autoimmune work up including ANA, ANCA, completement and immunoglobulin levels were unremarkable. HIV and hepatitis panel were negative. TTE negative for vegetations. LP could not be performed due to low platelets. He was started on ceftriaxone 2gm IV Q12. He was given 2 doses of IVIG and 3 days of methylprednisolone 1gm due to initial concerns IgA vasculitis.

Results
However, skin biopsy revealed small vessel neutrophilic vasculitis with thromboses consistent with purpura fulminan.

Conclusion
PF is an acute purpuric rash characterized by coagulation of the microvasculature, leading to purpuric lesions and skin necrosis. It is rapidly progressive and is often accompanied by disseminated intravascular coagulation and circulatory collapse. However, it is extremely rare in immunocompetent individuals. Upon our literature review there are only handful of case reports that has described the association of ISP with PF in immunocompetent individual. Our case highlights such rare association and stress on early recognition and treatment as it can cause significant morbidity and mortality.

Disclosures
All Authors: No reported disclosures.
1881. Detection of SARS-CoV-2 Transmission on a College Campus using a Combined Contact Tracing and Molecular Strategy
Authors: Brewer Jesse T , Wang Wei , Aranovich Irina , Notterman Daniel , Daskalaki Irini 
Published: December 2022

Abstract

Background
SARS-CoV-2 has caused unprecedented global disruption following its introduction into the human population. Beginning in August 2021, a residential college initiated an asymptomatic testing protocol using PCR-based detection of human saliva samples (Thermofisher, TaqPath SARS-CoV-2 Assay; QuantStudio v1.3). In January 2021 all students were invited to campus and were required to test once or twice weekly in an effort to isolate those positive (cases) as early as possible and minimize transmission.

Methods
Cases were contacted within 12 hours by trained clinical staff and interviewed with a standardized questionnaire to determine contacts and exposures. Positive samples were submitted for RNA-Seq analysis (ARTIC amplicon sequencing protocol, Illumina MiSeq) and analyzed using Nextclade and USHER (comparison data from GISAID). Using this sequence data, we monitored the evolution, transmission, and emergence of variants over time in the campus community.

Results
In March 2022 a one-week break and the activities preceding it were followed by an outbreak of COVID among campus members. All cases were attributed to the Omicron variant. Based on traditional contact tracing 10 presumed clusters of transmission were identified (34 students). Sequence data from these 34 samples were assembled to identify phylogenetic and molecular patterns of similarity. Several molecular signatures were identified. In a group of 5 cases, all were Omicron BA.2.9; these individuals comprised a clinical cluster of students who had travelled together. Other lineages were BA.2 (N=26), BA.1(N=2), BA.2.12. (N=3), BA.2.3 (N=1) and an Omicron Clade 21M variant that appeared to be a BA.1/BA.2 recombinant (N=2). The BA.2.12 samples were contributed over 2 days; they were found in two different clusters (a social club and an artistic group), demonstrating likely transmission between members. The BA.2 samples were distributed across a wide number of student groups, and while not identical with one another, did not fall into the clusters identified by contact tracing, suggesting endemic transmission across our campus.

Conclusion
This analysis demonstrates that molecular analysis of SARS-CoV-2 transmission can supplement and inform the data provided by clinical/epidemiological analysis of cases.

Disclosures
All Authors: No reported disclosures.
1891. Repeated Assessment of SARS-CoV-2 Seroprevalence among Health Care Workers Early in the Pandemic: Relationship to Workplace Exposures
Authors: Demian Sherry , Awuah Dominic O , Osterholzer Danielle , Altameemi Lina , Rios-Bedoya Carlos , Taftaf Ahmad , Nguyen Hoang C 
Published: December 2022

Abstract

Background
Early in the pandemic, heath care workers (HCWs) were deemed to be at high risk of acquiring SARS-CoV-2 from their patients and distanced themselves from their families. This study aimed to estimate the seropositivity of a cohort of healthcare over time while also looking for associations between seroconversion and hospital and community SARS CoV-2 exposures.

Methods
This is a prospective cohort study of HCWs from patient care (PC) and non-patient care (NPC) areas conducted from April 2020 through Dec 2020 at Hurley Medical Center in Flint, Michigan (MI). The first case of SARS-CoV-2 was diagnosed in MI on 3/10/2020. In early April 2020, HCWs underwent serum testing for total SARS-CoV-2 anti-spike protein antibody and completed a questionnaire to collect data on demographics, travel, job characteristics, in and out of hospital SARS-CoV-2 exposures, and use of personal protective equipment (PPE). The serum testing and survey were offered to the same HCWs in late May 2020 and again in December 2020. Statistical analysis such as Fisher's exact test and Student's t-test were used to determine if there was an association with SARS-CoV-2 antibody status for categorical and continuous variables, respectively.

Results
At baseline, 20/192 (10.4%) of HCWs were seropositive for SARS-CoV-2 total antibody with 9/20 (45%) providing PC. Job title was known for all participants however, initial survey completion was 79.6%. Eight weeks later, 13/131 (9.9%) were positive of which 5/13 (38.4%) were new seroconversions, 2/5 (40%) in PC. Eight months after the initial draw, 16/120 (13.3%) were positive with 13/16 (81.3%) new, 7/13 in PC (54%). The number of HCWs who tested positive at any time during the study was 38/192 (19.8%). No significant associations were found between seroconversion and taking care of COVID patients, any direct patient care duties, or other variables collected at the two-sided threshold of 0.05.

Conclusion
No association in this small study was found between PC and SARS-CoV-2 antibody seroconversion. HCWs in NPC areas were as likely to test positive as those in PC likely reflecting community prevalence. Universal masking at the medical center and use of full PPE to care for probable and confirmed COVID patients likely prevented higher rates of PC acquisition.

Disclosures
All Authors: No reported disclosures.