bluuebunny/crossref_metadata_2025_split huggingface dataset:
1808. Treatment Adherence and Outcomes Associated with Partial Oral Therapy vs. Intravenous Therapy in Patients with Serious Staphylococcus aureus Infections: A Comparative Effectiveness Study
Authors: Craig Alexandra , Shihadeh Katherine C , Miller Whitney , Young Heather , Knepper Bryan , Aragon Deborah , Jenkins Timothy C 
Published: December 2022

Abstract

Background
Randomized trials found oral step-down therapy to be as effective as intravenous (IV) therapy for infective endocarditis and bone and joint infections. However, the comparative effectiveness of IV versus oral step-down therapy for deep seated Staphylococcus aureus infections outside of the clinical trial setting is unknown. The objectives of this study were to compare treatment adherence and clinical outcomes between these two approaches in clinical practice.

Methods
This was a retrospective comparative effectiveness study involving adults hospitalized at an academic, safety net hospital between January 2019 to June 2021 with bacteremia, endocarditis, osteomyelitis, or septic arthritis due to S. aureus. Based on initial treatment plans, patients were categorized and analyzed in two groups: all IV or IV followed by oral step-down therapy. The co-primary outcomes were antibiotic adherence (percent of planned course received) and the proportion who completed therapy. The key secondary outcome of clinical failure was a composite of all-cause mortality, recurrent or new metastatic site of S. aureus infection, or requirement of an unplanned source control procedure.

Results
Of 249 patients included, 101 were in the all IV and 148 were in the oral step-down groups. Indications for treatment were osteomyelitis (72%), complicated bacteremia (25%), endocarditis (22%), septic arthritis (11%), and uncomplicated bacteremia (8%). Active substance abuse was observed in 43% of the IV group and 55% in the oral group. Between the all IV and oral step-down groups, antibiotic adherence rates did not differ significantly (Table); antibiotic therapy was completed by 93% vs 87% of patients (p = 0.13), respectively. Clinical failure occurred in 25% of the all IV group and 26% of the oral step-down group (p = 0.87). The frequency of other secondary outcomes was similar between groups; however, hospital length of stay was significantly longer in the IV group (Table). Table 1
Note: data presented as n (%) unless otherwise specified
*within 6 months of hospital admission date for index infection

Conclusion
In clinical practice, oral step-down therapy for serious S. aureus infections was associated with similar rates of treatment adherence and completion, clinical outcomes and less health care resource utilization compared with IV therapy. Our findings support use of oral step-down therapy as an effective alternative to IV therapy.

Disclosures
All Authors: No reported disclosures.
1821. Clinical Characteristics of Staphylococcus aureus Bacteremia with the Skip Phenomenon: a Case Control Study.
Authors: Tsuchido Yasuhiro , Shinohara Koh , Yukawa Satomi , Noguchi Taro , Yamamoto Masaki , Matsumura Yasufumi , Nagao Miki 
Published: December 2022

Abstract

Background
Staphylococcus aureus bacteremia (SAB) is one of the most common causes of persistent bacteremia, which is associated with complicated disease and poor clinical outcome. “The skip phenomenon (SP)” was recently proposed concept which might exhibit fluctuating blood culture positivity, but its clinical significance remained to be clarified. The aim of the study was to evaluate the clinical characteristics of SAB with the SP.

Methods
This is a retrospective case-control study conducted at 1141-bed university hospital during 2006-2021. Adult inpatients with more than 3 days of SAB were included. Cases were patients with SP, and controls were the rest of the patients. Duration of bacteremia was defined as bacteremic days under active antibiotic therapy counting the first day as day 1. SP was defined as at least 1 day of negative blood cultures following documented S. aureus bacteremia and preceding recurrence of a positive blood culture, which was taken within 14 days from last positive culture. Patient characteristics including medical comorbidity, implanted hardware, and focus of infection were reviewed.

Results
Of the 149 patients, 17 (11.4%) had the SP. A total of 20 skip phenomenon episodes among 17 cases were observed. Three patients had 2 episodes of SP. Of the 20 episodes of the SP, 7 (35.0 %) were confirmed with single set, and 13 (65.0 %) were confirmed with 2 sets of negative blood culture. The median interval from first positive blood culture to first SP episode in each case was 7 days (interquartile range [IQR], 6-16 days). Of 20 episodes of SP, 18 (90.0 %) were accompanied with fever as an indication for taking blood culture. The cases (n=17) were more likely than controls (n=132) to have a longer duration of bacteremia (median [IQR], 14 [11–36] days, vs 4 [3–7] days; p &lt; 0.001), and diabetes mellitus (52.9 % vs 25.0 %, p=0.023). There was no significant difference in deep-seated infection (64.7 % vs 48.5 %, p=0.303), methicillin resistance rate (76.5 % vs 50.0 %, p=0.068), and 90-day mortality (17.6 % vs 27.3 %, p=0.561) between cases and controls.

Conclusion
Our findings suggest that we should consider to take blood culture repeatedly when clinically indicated, even if we confirmed the negativity once before.

Disclosures
All Authors: No reported disclosures.
1822. Clinical Outcomes Associated with Oral Beta-Lactam Therapy versus Oral Fluoroquinolones/TMP-SMX for Uncomplicated Gram-Negative Bacteremia
Authors: Kaur Satwinder S , Babic Jessica T , Nguyen Steven , Patel Shivani 
Published: December 2022

Abstract

Background
Agents commonly used as oral step-down therapy in Enterobacterales bacteremia include fluoroquinolones and TMP-SMX. The use of these oral agents have been associated with adverse events. Oral β-lactams are not recommended to treat Enterobacterales bacteremia because of concerns for sub-therapeutic serum concentrations. Given the limited data on clinical effectiveness of oral β-lactams and increased limitations with fluoroquinolones and TMP-SMX, oral β-lactams may be an alternative option. The purpose of this study is to evaluate the clinical effectiveness in patients transitioned to oral β-lactams versus fluoroquinolones or TMP-SMX for the step-down treatment of uncomplicated Enterobacterales bacteremia.

Methods
A multi-center, retrospective, propensity-score matched, observational cohort study was conducted from July 1, 2017 to December 31, 2020, at 11 Memorial Hermann Health System hospitals among 690 patients with uncomplicated Enterobacterales bacteremia. Patients were included if they received &gt; 1 day of intravenous antibiotic therapy followed by definitive oral step-down therapy with a β-lactam, fluoroquinolone, or TMP-SMX. The primary outcome was treatment failure within 30 days of starting oral antibiotics, defined as at least one of the following: recurrent bacteremia, transition to IV antibiotics, new-onset sepsis, 30-day readmission, or 30-day all-cause mortality.

Results
After the patients were propensity score matched 1:1, a total of 199 patients with uncomplicated Enterobacterales bacteremia were included in each group. Treatment failure occurred in 8 patients (4%) who received β-lactams and 10 patients (5%) who received fluoroquinolones or TMP-SMX (OR, 0.79 [95% CI, 0.306-2.04] p-value 0.629). Median length of hospital stay was 5 days for both groups (p-value 0.911), and median duration of oral antibiotics was 10 days in the fluoroquinolone or TMP-SMX group and 11 days in the β-lactam group (p-value 0.377).

Conclusion
Based on the results of this study, no significant difference in treatment failure was seen in patients who were transitioned to β-lactams versus fluoroquinolones or TMP-SMX as oral step-down therapy for uncomplicated Enterobacterales bacteremia. Oral β-lactams appear to be a safe and effective option.

Disclosures
All Authors: No reported disclosures.
1824. Combination therapy of daptomycin/colistin for extreme drug resistant Acinetobacter baumannii bacteremia
Authors: Lampada Charis , Kourti Maria , Charisi Konstantina , Iosifidis Elias , Zarras Charalambos , Roilides Emmanuel , Antachopoulos Charalambos 
Published: December 2022

Abstract

Background
There are experimental data demonstrating synergistic in-vitro activity of colistin and daptomycin against extremely drug-resistant (XDR) strains of Acinetobacter baumannii.Aim of this study is the description of a case-series of patients with confirmed XDR A. baumannii bloodstream infection (BSI) receiving an antimicrobial regimen including colistin and daptomycin.

Methods
Prospective study of patients with BSI caused by XDR A. baumannii from May 2021 to February 2022 in a tertiary level hospital. Demographic, clinical and laboratory data were recorded and evaluated from all patients. BacT Alert system (BiomerieuxR) was used for blood cultures and bacterial identification and susceptibility testing was performed using VITEK® 2. Colistin susceptibility testing (dilution method) were interpreted in accordance to Clinical and Laboratory Standards Institute (CLSI) criteria.

Results
A total of 16 episodes of XDR A. baumannii were recorded in 16 patients (14 males). Median age was 60 (range 38-85) years. Ten patients (56.2%) were hospitalized in medical wards, and 43.8% in surgery wards. One-third of patients had previously been admitted to the Intensive Care Unit, while all patients had an indwelling central vascular catheter. Fourteen of the 16 XDR strains of A. baumannii were also resistant to colistin. Also, 2 of the 16 strains had a MIC of 2μg/ml for tigecycline, while in the remaining 14 the MIC was &gt; 2μg/ml. All isolates had meropenem MIC &gt;16μg/ml. All patients received a combination of colistin -daptomycin -meropenem -tigecycline. Clinical and laboratory improvement was noted in 15 of the 16 patients within the 14 days of treatment. Fifteen out of the 16 patients showed a microbiological response: the mean duration between the start of treatment and the first negative blood culture was 12 days.Finally, no patient experienced a marked increase in CPK due to daptomycin use.

Conclusion
The outcome of this case series of patients receiving colistin-daptomycin combination as part of a broader synergistic antimicrobial regimen to treat XDR A. baumannii was satisfactory, with no significant adverse reactions. This potential clinical benefit of the colistin/daptomycin combination should be further evaluated in a larger comparative study.

Disclosures
All Authors: No reported disclosures.
2314. Hospitalizations and Antibiotic Use in the Year Prior to an Incident C. difficile Infection for Medicare Beneficiaries in Four States, 2016–2018
Authors: Hatfield Kelly M , Baggs James , Reddy Sujan , Aranmolate Rasaki , Meek James , Fridkin Scott , Szydlowski Jill , Hatwar Trupti T , Dumyati Ghinwa , Watkins Jasmine , Wilson Christopher , Clifford McDonald L , Jernigan John A , Guh Alice 
Published: December 2022

Abstract

Background
Studies describing risk factors for Clostridioides difficile infection (CDI) are often limited in their ability to identify potentially important exposures occurring long before diagnosis. We describe hospitalizations and antibiotic use (AU) occurring up to one year prior to CDI diagnosis among Medicare beneficiaries.

Methods
We studied incident CDI cases (positive C. difficile test in a person ≥65 years without a positive test in the prior 8 weeks) identified during 2016–2018 through population-based CDI surveillance from four states participating in the Centers for Disease Control and Prevention’s Emerging Infections Program. The analysis included specimens collected in all settings and was limited to case patients who were identified as having fee-for-service Medicare and Part D drug coverage for the year preceding specimen collection. Inpatient hospitalization data was extracted from Medicare Provider Analysis and Review (MEDPAR) files and outpatient AU (prescriptions filled) was determined using Part D drug event files. Timing of hospitalizations and antibiotic prescriptions were described as recent (0–3 months prior to specimen collection) or remote (4–12 months prior).

Results
Of 1,953 CDI cases, 1,594 (82%) filled ≥1 course of outpatient antibiotics in the prior year; 805 (41%) filled an antibiotic both recently and remotely, 497 (25%) only remotely, and 292 (15%) only recently.
Cases with outpatient AU received a median of 23.5 (IQR 12–46) total days supplied, and a median of 2 different antibiotic classes (IQR 1 – 3). The most frequent antibiotic classes filled include fluoroquinolones (17% of all antibiotics filled), 1st generation cephalosporins (10%), and folate pathway inhibitors (10%).
Overall, 1,314 (67%) cases were hospitalized in the prior year; 569 (29%) were hospitalized both recently and remotely, 446 (23%) only recently, and 299 (15%) only remotely. Median length of stay was 13 days (IQR 6–28).
A total of 142 cases (7%) did not have hospitalization or outpatient AU in the prior year, and 1,097 (56%) had both.

Conclusion
Incident CDI cases have substantial exposure to recent and remote hospitalization and outpatient AU. Understanding cumulative effects of multiple risk factors can guide prevention strategies, including antibiotic stewardship efforts.

Disclosures
Scott Fridkin, MD, Pfizer: Grant/Research Support Ghinwa Dumyati, MD, Pfizer: Grant/Research Support.
1835. Evaluation of Predicting Performance of POSITIVE, PREDICT and VIRSTA Score for Infective Endocarditis in Patients with Staphylococcus aureus Bacteremia
Authors: Pinargote Paulette , Salazar Wilmer , Katubbadi Ayeesha , Patel Neev , Alam Mohammad , Bhuiyan Mohammad , Vanchiere John 
Published: December 2022

Abstract

Background
Prompt identification of Infective Endocarditis (IE) in patients with Staphylococcus aureus bacteremia (SAB) is important as delayed diagnosis results in 15-20% increased mortality. Predictive clinical scoring strategies have been developed to optimize the diagnostic process, particularly the use of invasive methods such as Transesophageal Echocardiography(TEE), known to be superior to Transthoracic Echocardiography but is not suitable for all patients. Three scoring systems have been proposed to predict the risk of IE: VIRSTA, PREDICT and POSITIVE. We compared these scoring strategies in combination with other clinical data to test the hypothesis that inclusion of time to blood culture positivity(TTP) in the scoring strategies might improve the sensitivity and specificity of clinical risk stratification.

Methods
Adults (≥ 18y) with SAB admitted to Ochsner LSU Health Shreveport in 2020-2021 were retrospectively screened. Patients with polymicrobial bacteremia, with index blood cultures obtained at a different institution and without cardiac imaging were excluded. In this preliminary analysis, 60 patients (30 with and without IE) were studied. IE was defined as patients who met modified Dukes criteria for definite IE. The three scores were calculated for each subject. TTP, defined as the time from incubation to automated detection, was obtained from the microbiology laboratory. Clinical predictors of IE were identified using multivariable logistic regression analysis.

Results
The demographic, baseline characteristics and mode of presentation, was no different in both groups based on analysis of &gt;50 factors. The mean TTP for subjects with and without IE were no different (9.65h vs 11h, p=0.12) TTP≤13h as an independent variable was found to be sensitive but not specific. VIRSTA was found to be the most sensitive scoring method. POSITIVE, which includes TTP as a component, was the most accurate, but least sensitive method. Addition of TTP≤13h to VIRSTA and PREDICT increased sensitivity but lowered specificity.

Conclusion
While the sensitivity of scoring strategies is acceptable, none of the proposed methods has adequate specificity. Larger studies are needed for the development of a highly specific and accurate scoring method that includes classic risk factors and TTP.

Disclosures
All Authors: No reported disclosures.
1843. Intravenous versus Partial Oral Antibiotic Therapy in the Treatment of Uncomplicated Bloodstream Infection due to Streptococcus species
Authors: Broermann Lynn , Al-Hasan Majdi N , Al-Hasan Majdi N , Withers Sarah , Benbow Kristina L , Ramsey Taylor , Ogren Katelyn , McTavish Meghan , Webster William , Winders Hana R 
Published: December 2022

Abstract

Background
Effectiveness of oral antibiotics for transition of therapy in uncomplicated bloodstream infections (BSI) due to Streptococcus species remains unclear. This retrospective cohort study examines effectiveness of partial oral antibiotic regimens in patients with uncomplicated BSI due to Streptococcus species compared to standard intravenous (IV) only therapy.

Methods
Adult patients with uncomplicated BSI due to Streptococcus species from April 2016 through June 2020 in 7 hospitals within Prisma Health in South Carolina were evaluated. Patients who died within 7 days of BSI were excluded to reduce the impact of survival bias. Multivariate Cox proportional hazards regression was used to examine time to treatment failure, defined as a composite of all-cause mortality and BSI recurrence within 90 days.

Results
A total of 222 patients with Streptococcus species BSI were included in the analysis. Overall, the median age was 62 years, and 116 (52.3%) were men. Beta-hemolytic streptococci (87; 39.2%) were the most common bloodstream isolates, followed by S. pneumoniae (76; 34.2%) and viridans group streptococci (59; 26.6%). Among this cohort, 99 patients received only IV antibiotics, and the remaining 123 received partial oral therapy. The median duration of therapy in both groups was 14 days, and median duration of IV antibiotics prior to oral transition was 4 days. Most patients in the partial oral group were transitioned to either oral beta-lactams (62; 50.4%) or fluoroquinolones (47; 38.2%). Of the IV only group, 46 (46.5%) required outpatient IV antibiotics. Treatment failure rates were 12.0% and 4.4% in the IV only and partial oral therapy groups, respectively (p=0.04). After adjustments for age, chronic comorbidities, and initial response to therapy within the first 72-96 hours, there was no difference in the risk of treatment failure in the partial oral compared to IV only group (hazards ratio 0.55, 95% CI 0.19-1.64; p=0.28).

Conclusion
Transitioning patients from IV to oral antibiotics may be a reasonable strategy in the management of uncomplicated BSI due to Streptococcus species. Partial oral therapy does not seem to have a higher treatment failure rate than standard IV only therapy and may spare many patients from outpatient IV antibiotics.

Disclosures
All Authors: No reported disclosures.
2316. Impact of Surveillance and Decolonization on Methicillin-resistant Staphylococcus aureus Infection Rates in a Neonatal Intensive Care Unit
Authors: Hiermandi Nahid , Foster Catherine , Purnell Krystal , Campbell Judith R , Marquez Lucila 
Published: December 2022

Abstract

Background
Neonates colonized with methicillin-resistant Staphylococcus aureus (MRSA) are at high risk of developing life-threatening MRSA infection. In neonatal intensive care units, surveillance for MRSA colonization and decolonization of positive infants aims to interrupt MRSA transmission and progression to infection.

Methods
In this retrospective study, we compared rates of MRSA infections before and after implementation of an MRSA surveillance and decolonization protocol in a 42-bed neonatal intensive care unit. Infections from Jan 2014 to Dec 2020 were reviewed. The protocol was introduced in late October 2016 and fully implemented by Feb 2017. MRSA colonization was initially assessed with cultures of three body sites and later the methodology was changed to PCR. Colonized infants were treated with topical mupirocin and 2% chlorhexidine gluconate wipes. MRSA infection was defined as any specimen from which MRSA was isolated. Multiple positive specimens from the same site were considered the same infection if within a 14-day window. Infection rates were calculated as unique infections per 1000 patient days. An interrupted time-series analysis was performed on Stata 14.2. This study was approved through the Baylor College of Medicine Institutional Review Board.

Results
While we continued to identify colonized infants in the unit, monthly infection rates in the post-intervention period never reached the peak rates in the pre-intervention period and clusters of infections have been eliminated (Figure 1). Prior to the intervention in Feb 2017, the rate of infection increased by 0.06 infections per 1000 patient days every month (p=0.124, CI = -0.017, 0.137). During the first month after full implementation of the intervention, the infection rate decreased by 1.522 infections per 1000 patient days (p=0.145, CI = -3.579, 0.534) followed by a monthly rate decrease of 0.066 infections per 1000 patient days (p=0.088, CI = -0.142, 0.010) (Figure 2).

Conclusion
We found a sustained trend towards decreased MRSA infections after implementing MRSA surveillance and decolonization. Further studies should explore adherence to decolonization, whether decolonization is enduring and what risk factors lead to recurrence of colonization.

Disclosures
All Authors: No reported disclosures.
1851. Recurrence of Streptococcus agalactiae Bacteremia - Risk Factors and Complications
Authors: Wang Taylor B , Zimilover Adam , Garellek Jonathan , Mahvish Gull , Parvez Hina , Given Hafsa No Name , Singh Damanbir , Patel Pranavkumar , Patel Pranavkumar , Gorlin Margaret , Kim Angela , Flannery Sarah , Epstein Marcia , Smith Miriam A 
Published: December 2022

Abstract

Background
The primary objective was to identify the frequency of recurrent Streptococcus agalactiae (GBS) bacteremia and associated risk factors for recurrence. The secondary objective was to determine the source of the initial GBS bacteremia and complications.

Methods
This was a retrospective observational study evaluating patients who were admitted to any of the 12 hospitals within the Northwell Health System from 1/1/2016 to 1/1/2020. Non-pregnant patients ≥ 18 years of age with GBS bacteremia were included. Recurrence was defined as admission due to GBS bacteremia within 1 year after a positive blood culture. Statistical methods performed include t-test or Wilcoxon Rank Sum test, Chi-square, Fisher exact tests, and both univariable and multivariable logistic regressions.

Results
390 patients met inclusion criteria with a median age of 63 years old. Majority were white (61.5%) and male (54.1%). Recurrence was found in 18 of 390 patients (4.62%). There was a significant increase in recurrence for patients allergic to penicillin or cephalosporins (p&lt; 0.03), patients with implantable cardiac devices (ICDs) (p&lt; 0.03) and patients who did not receive β-lactams and/or vancomycin as initial treatment (p&lt; 0.05). 6 of the 18 patients were allergic to penicillin or cephalosporins. The estimated odds of recurrence in patients with ICDs were ∼5.4 times the odds of those without ICDs controlling for allergies (p&lt; 0.04, 95% CI 1.7 – 20.0) or controlling for initial antimicrobial treatment (p&lt; 0.04, 95% CI 1.5 – 18.7). The most common sources of GBS bacteremia were skin and soft tissue (35.1%), unknown (27.9%), and urinary tract (6.41%). Endocarditis was diagnosed in 8 patients (2.05%) via transesophageal echocardiogram. Other complications of GBS bacteremia included vertebral osteomyelitis (3.08%), epidural abscess (0.77%), and septic arthritis (0.77%). Median treatment duration was 15 days, with no significant difference in recurrence (p=0.75).

Conclusion
GBS bacteremia recurred in 4.62% of patients. Recurrence was significantly associated with ICDs, penicillin or cephalosporin allergies, and not receiving β-lactam and/or vancomycin-based regimens as initial therapy. The substantial rate of recurrent GBS bacteremia has important clinical implications.

Disclosures
All Authors: No reported disclosures.