bluuebunny/crossref_metadata_2025_split huggingface dataset:
191. Oral Antibiotic Step-Down Therapy for Non-Staphylococcal Gram-Positive Bloodstream Infections
Authors: Gandhi Kelvin , Wrzesinski Magdalena , Bunnell Kristen , Long Ashley , Hutzley Vanessa , Hamilton Rachel , Sundsbak John , Gibble Allison 
Published: December 2021

Abstract

Background
Bloodstream infections are traditionally treated with intravenous (IV) antimicrobial therapy, which may increase length of stay and healthcare costs. The purpose of this study is to evaluate if oral antibiotic step-down therapy for non-staphylococcal gram-positive bloodstream infections (GP-BSIs) is non-inferior to IV antibiotics.

Methods
This single-center, retrospective cohort study included patients with a non-Staphylococcus aureus, non-Staphylococcus lugdunensis GP-BSI from January 2017 to December 2019. Patients were excluded if they fit any of the following criteria: organism identified as contaminant, polymicrobial BSI, recurrent BSI within the past 90 days, or receipt of an effective antibiotic for a duration longer than what is indicated for BSI treatment. Patients were categorized into those who received an IV antibiotic for the total duration of therapy and those who received an oral step-down antibiotic for at least one-third of the treatment course. The primary composite outcome was the incidence of 90-day clinical failure consisting of 90-day all-cause mortality, change in therapy due to inadequate clinical response, and 90-day BSI recurrence. The secondary outcomes included the individual components of the primary composite outcome, line-related complications, and hospital length of stay. Bivariate analysis was conducted to assess for predictors of 90-day clinical failure.

Results
A total of 308 patients were included (oral group, n=94; IV group, n=214). Pitt Bacteremia Scores were low overall, but higher in the IV group (0 vs 1, p=0.045). The oral group had a higher proportion of GP-BSI caused by streptococcal species (76% vs 61%, p&lt; 0.001). The oral group had a lower incidence of 90-day clinical failure and was found to be noninferior to the IV group (9% vs 14%; mean difference -5%, 90% CI -12.7 to 2.6). The IV group had a longer hospital length of stay (4 vs 6 days, p&lt; 0.001), however there were no other significant differences in secondary outcomes. Bivariate analysis found no significant predictors of 90-day clinical failure.

Conclusion
Oral antibiotic step-down therapy was found to be non-inferior to IV antibiotic therapy, and thus may be an alternative option for the treatment of non-staphylococcal GP-BSIs.

Disclosures
All Authors: No reported disclosures
193. Evaluation of Severity Scores in Patients with Methicillin-Susceptible Staphylococcus aureus Bloodstream Infections
Authors: Craig Alexandra , Wagner Jamie , Barber Katie 
Published: December 2021

Abstract

Background
Staphylococcus aureus bloodstream infections (BSIs) are associated with increased morbidity, mortality, and healthcare costs. Severity of illness scores help stratify critically ill patients and assist providers in making decisions. The quick Pitt (qPitt) score is a reliable predictor of mortality in patients with Gram-negative BSIs (AUROC 0.85); however, limited data exist for using the qPitt in methicillin-susceptible S. aureus (MSSA) BSIs.

Methods
This retrospective cohort evaluated patients with MSSA BSIs. The primary outcome was the discrimination of the qPitt in predicting hospital mortality compared to the Pitt bacteremia score (PBS). Secondary outcomes were clinical failure and the predictive discrimination of the qPitt score in comparison to other severity scoring modalities. Categorical data were analyzed using chi-square test or Fisher’s exact test. Continuous data were analyzed using Student’s t-test or Mann-Whitney U. Predictive discrimination was determined by the area under receiver operating characteristic curve.

Results
One hundred patients were included with the mean age of 52 years (p=0.84) and a BMI of 30 kg/m2. Males were predominant (70%). Mortality occurred in 13 patients who had more ICU admissions (92% vs. 37%; p&lt; 0.01) and longer ICU LOS (10 vs. 5 days; p=0.03) despite similar baseline comorbidities. Time to definitive therapy was longer in the mortality group than non-mortality group (28 vs. 23 hours; p=0.79) though antimicrobial use did not differ. As outlined in Figure 1, the mortality group had higher severity of illness scores. The qPitt had a ROC of 0.83, indicating high discrimination. Overall, qPitt was found to be similarly predictive than PBS, equally as predictive as qSOFA, and more predictive than SIRS and APACHE II (Figure 1). Clinical failure occurred in 23% of patients; 54% of the mortality group experienced persistent BSI vs. 11% in the non-mortality group (p&lt; 0.01), and 3% of the non-mortality group had recurrent infection (p=1.00).

Conclusion
Compared to previous studies on Gram-negative BSIs, the qPitt performed similarly in MSSA BSIs. The qPitt can be considered for use in predicting mortality for patients with MSSA BSIs; however, further studies are needed to confirm these results.

Disclosures
All Authors: No reported disclosures
194. Antimicrobial Susceptibility Data of Staphylococcus lugdunensis After the Implementation of Rapid Molecular Blood Culture Diagnostics (Verigene® Gram-Positive Blood Culture Nucleic Acid Test)
Authors: Constance Kristin , Hunt Alauna , Karimaghaei Sam , Chijioke Juliet , Chavez Violeta , Wanger Audrey , Masayuki Nigo 
Published: December 2021

Abstract

Background
S. lugdunensis is a coagulase negative staphylococci (CoNS) demonstrating high level pathogenicity. In contrast to other CoNS, S. lugdunensis (SL) remains susceptible to most antibiotics. Prior to the implementation of Verigene®, SL was identified by provider request only. We sought to describe the susceptibility data of SL isolated from blood culture after the implementation of multiplex PCR, as well as to determine the correlation of the mecA gene provided by Verigene® and oxacillin resistance.

Methods
Retrospective review of all blood culture isolates positive for SL from two major hospital systems, Memorial Hermann Hospital System (14 hospitals) and HarrisHealth System (two acute care hospitals) identified on Verigene® PCR. Multiple isolates detected from the same patients were excluded from this analysis. Memorial Hermann utilized Microscan®, and HarrisHealth utilized BD Phoenix® for susceptibility testing.

Results
Between 2017 – 2021, 157 patients were identified with SL positive blood cultures. Of them, 141 isolates had susceptibility data collected, which is summarized in table 1. Resistance rates were highest amongst clindamycin 97/141 (68.8 %) susceptible, erythromycin 98/141 (69.5%) susceptible, and oxacillin 120/141 (85.1%) susceptible. 127/141 (90.1%) of isolates were tested for mecA on Verigene®. 13 of 21 oxacillin resistant isolates were from pure culture, of these isolates, none had mecA detected.

Conclusion
In our study, clindamycin and erythromycin demonstrated similar susceptibility compared to prior studies in the literature, however oxacillin susceptibility rate was lower than expected at 85.1%, compared to 95.3% in a prior large-scale United States based study in 2017. Absence of mecA gene detection on multiplex PCR did not correlate with oxacillin susceptibility suggesting that oxacillin susceptibility cannot be accurately predicted by the use of multiplex PCR systems, such as Verigene®, as demonstrated in Table 2. Our study also suggested that increased prevalence of oxacillin resistant SL isolates may be emerging.

Disclosures
All Authors: No reported disclosures
197. A Predictive Model for the Prompt Identification of Suspected Sepsis Patients with High Death Risk
Authors: Vrandecic Erika , Oliveira Joel T , Couto Bráulio R G M 
Published: December 2021

Abstract

Background
How to improve the high mortality rate of sepsis? The prompt identification of at-risk patients, and the interdisciplinary sepsis treatment protocol implementation are interventions that can reverse such unacceptable outcome. The objective of our study is to summarize main results of the protocol for the management of sepsis and septic shock, implemented at Biocor Instituto, a general hospital in Belo Horizonte, a 3,000,000 inhabitants city from Brazil.

Methods
Prospective cohort study of patients with sepsis, evaluated between May/2018-Apr/2020. Univariate and multivariate analysis by logistic regression to identify risk factors for hospital death.

Results
Over 28 months, 220 patients were included in sepsis protocol: 121 hospital deaths, a crude mortality = 121/220 = 55% (95%C.I. = [48%;62%]). 136 patients (62%) came from the emergency room. In 97 cases (44%) it was possible to isolate 111 microorganisms, with a predominance of Klebsiella, E.coli, and S.aureus. 75% of the cases (165) had definition of APACHE, with the absolute majority of these (88%) having APACHE between 25 and 40. Most patients (52%) received antibiotic (ATB) in 15 minutes and only 4% received ATB after 60 minutes of waiting time. In 198 patients (90%) it was possible to identify the focus of sepsis, with a predominance of pulmonary (47%), urinary (21%) and abdominal (15%). Hospital mortality varied from 30 to 62%, when the focus was pulmonary (p-value = 0.045). In univariate analysis (Figure 1), pulmonary sepsis, creatinine, lactate, and APACHE were significantly associated with hospital death. The time for ATB administration was typically close to 20 minutes, and time to receive the therapeutic antibiotic were not associated with the patient’s death. By using the logistic model (Figure 2) to assign cases of predicted hospital death for probabilities &gt;= 0.5 and controls for probabilities &lt; 0.5, the prediction model had a sensitivity of 0.68 (0.59–0.76), a specificity of 0.58 (0.48–0.67), an area under the curve of the receiver operating characteristic curve of 0.75 (0.68–0.82). There was no significant difference between observed versus expected mortality by APACHE (Figure 3).
Figure 1. Univariate analysis to identify risk factors for hospital death.

Figure 2. Logistic model for predicting hospital death.

Figure 3. Observed X Expected/severity-adjusted mortality (APACHE).

Conclusion
The logistic model developed uses only creatinine and lactate data to predict suspected sepsis patients with high death risk.

Disclosures
All Authors: No reported disclosures
199. Prospective Observational Cohort Of Transition to Oral Antibiotics in Persons Who Inject Drugs with Invasive Infections
Authors: Lewis Sophia , Marks Laura , Stephen Liang , Nolan Nathan , Durkin Michael 
Published: December 2021

Abstract

Background
Persons who inject drugs (PWID) are at increased risk of invasive bacterial infections. Increasing data supports the efficacy of transition to oral antibiotic therapy to complete treatment of invasive bacterial infections including osteomyelitis and endocarditis. The aim of this study is to evaluate the impact of transition to oral antibiotics on a prospective observational cohort of PWID.

Methods
We prospectively analyzed PWID admitted 2/2020 - 2/2021 at Barnes-Jewish Hospital in St. Louis with osteomyelitis, endocarditis, epidural abscesses or septic arthritis. All patients were offered multidisciplinary support during their inpatient hospitalization including addiction medicine consultation and medications for opioid use disorder, if appropriate. Health coaches and case managers met with patients during their hospitalization and followed patients for up to 90 days after discharge. Patients were offered the option of transition to oral antibiotics if they were not able to complete recommended IV antibiotics. Patients discharged on oral antibiotics were offered post-discharge infectious diseases follow-up. Antibiotic adherence was documented by health coaches through phone out-reach. We collected data on demographics, comorbidities, microbiologic data, antibiotic selection, mortality and readmission rates. We compared 90-day readmission rates between PWID who completed IV antibiotics inpatient and those who discharged early with oral antibiotics.

Results
Of 166 PWID, 61 completed IV antibiotics inpatient (37%) while 105 were discharged with oral antibiotics (63%). Causative pathogens were not significantly different between inpatient IV vs oral antibiotics; MSSA (34.4% vs 35.2%, p= 0.92), MRSA (34.4% vs. 28.6%, p=0.43), or streptococcal species (26.6% vs. 24.8%, p=0.85). Of patients discharged on oral antibiotics 7.6% had documented non-adherence to therapy, 23% had unknown adherence and 67% had documented adherence. There was no significant difference in all-cause 90-day readmission rates (p=0.819) (Figure 1).
All-cause readmissions by antibiotic strategy

Conclusion
Oral antibiotic regimens provided similar efficacy to IV antibiotics in our prospective cohort analysis of PWID.

Disclosures
All Authors: No reported disclosures
202. The Impact and Safety of Discontinuing Routine Surveillance Blood Culture Monitoring in Allogeneic Hematopoietic Cell Transplant Recipients
Authors: Garner Will , Oleksiuk Louise-Marie , Malek Elisa , Reinecke Kristen , Dorritie Kathleen , Im Annie , Ito Sawa , Rothenberger Scott , Agha Mounzer , Haidar Ghady 
Published: December 2021

Abstract

Background
Bloodstream infections (BSI) cause significant morbidity and mortality after hematopoietic cell transplant recipients (HCT). Surveillance blood cultures (SBC) are commonly used to decrease the risk of developing BSI but prior data suggest limited clinical utility. At our center, SBC monitoring was discontinued on 12/1/2019. This is a single center study evaluating the impact and safety of discontinuing routine SBC monitoring.

Methods
Retrospective review of allogeneic hematopoietic cell transplant recipients (HCTR) seen before (12/1/2017 – 11/30/2019) and after (12/1/2019 - 12/1/2020) discontinuation of SBC. We evaluated utility of SBC and the impact of discontinuation of SBC on admissions, mortality, and other variables.

Results
One hundred thirty-six and 133 HCTR were followed before and after discontinuation of SBC, respectively. Median (range) ages were 58 (22-73) and 56 (19-73); 60 (44%) and 59 (44%) were female, respectively. The most common cancer was acute myelogenous leukemia (71 (52%) and 61 (46%)); 87 (64%) and 77 (58%) had graft-versus-host disease respectively. Pre-intervention, 1946 SBCs were drawn; 81/1946 (4.2%) were positive. Post-intervention, 29 SBC were drawn; 1/29 (3.4%) were positive. Of the 82 positive SBCs, 63 (77%) were skin flora, and 9 (11%) were gram negative rods. No cultures grew Staphylococcus aureus or fungi. Fifty-one (63%) of the positive SBC resulted in an admission; median (range) length of stay (LOS) was 3 days (1-11). Following discontinuation of SBC, median monthly blood culture-related admissions decreased from 3 (0-6) to 1 (0-3) shown in Figure 1. In the pre-intervention period, there were 2 BSI-related deaths, and 0 following cessation of SBCs.
Figure 1. Monthly Hospital Admissions for Positive Outpatient Blood Cultures

Conclusion
SBCs were infrequently positive and often resulted in unnecessary antibiotic use, admission, and clinical interventions. After SBC monitoring was discontinued, there was a decrease in hospital admissions and health care utilization for positive blood cultures drawn in the outpatient setting. This intervention did not negatively impact clinical outcomes, including BSI-related mortality. Discontinuation of SBC appears to be safe and results in a reduction in healthcare utilization. Centers performing SBC should consider eliminating this practice.

Disclosures
Ghady Haidar, MD, Karuys (Grant/Research Support)
203. Gardnerella vaginalis Bacteremia in Male Patients: A Case Series and Review of the Literature
Authors: Akamine Christine , Tavakoli-Tabasi Shahriar , Chou Andrew , Musher Daniel M 
Published: December 2021

Abstract

Background
Introduction: Gardnerella vaginalis is a colonizer of the female genitourinary tract and can cause serious morbidity as a pathogen. It is an uncommon cause of infection in men and bacteremia with this organism is rare. We describe two cases of G. vaginalis bacteremia in male patients. A literature search was performed for cases of G. vaginalis bacteremia in men. A total of 13 patients were identified and discussed.

Methods
Case 1: A 52-year-old man with diabetes and prior nephrolithiasis presented for dysuria, hematuria, and left sided flank pain. He was febrile and tachycardic with mild left costovertebral angle tenderness, leukocytosis and acute kidney injury. Urinalysis revealed pyuria. Computed tomography of the abdomen and pelvis showed pyelonephritis and a small calculus of the proximal left ureter. He was treated with ceftriaxone and then piperacillin-tazobactam. Aerobic culture of the urine yielded &lt; 10,000 cfu/mL of mixed gram-positive flora. Blood cultures yielded G. vaginalis after 48 hours. He was treated with ciprofloxacin 500 mg orally twice daily for 7 total days and clinically recovered. Case 2: A 61-year-old man with alcohol use disorder and gout, presented with altered mental status. He had leukocytosis and acute kidney injury and was treated with vancomycin and cefepime with clinical improvement. Admission blood cultures demonstrated G. vaginalis in the anaerobic bottle of 1 of 2 cultures, reported 96 hours after collection. Urine culture was negative. The patient was treated with amoxicillin-clavulanate on discharge to complete a 14-day course with clinical resolution.

Results
see above
Gram stain of G. vaginalis on blood culture

Conclusion
Discussion: G. vaginalis is a facultative anaerobic gram-positive pleomorphic rod, which can be gram variable due to poor staining of the thin peptidoglycan cell wall. Isolation and identification are often delayed. Bacteremia in men is rare but nearly all have originated in the genitourinary tract. The most severe cases of G. vaginalis bacteremia implicate endocarditis, urethral stricture and an empyema as the sources. Collection of blood cultures and speciation are often delayed, ranging from 48 hours to 7 days. Selection and duration of treatment have ranged widely in previously reported cases, likely due to the lack of guidance regarding effective treatment.

Disclosures
Andrew Chou, MD, bluebird bio (Shareholder)
204. Clinical Outcomes with Ceftaroline Monotherapy versus Daptomycin-Ceftaroline Combination Therapy in the Treatment of Methicillin-Resistant Staphylococcus aureus Bacteremia
Authors: Andonie Gabriela , Hand Elizabeth O , Reveles Kelly R , Traugott Kristi A 
Published: December 2021

Abstract

Background
Methicillin-resistant Staphylococcus aureus (MRSA) bacteremia is associated with poor outcomes and increased mortality. Daptomycin (DAP) and ceftaroline (CPT) in combination has been explored as a potential treatment option and showed improved outcomes compared to vancomycin/standard therapy. CPT monotherapy has been evaluated as salvage therapy for MRSA bacteremia but, to our knowledge, not as a comparator to DAP-CPT combination therapy. The purpose of this study is to compare the clinical outcomes of DAP and CPT combination therapy to CPT monotherapy in the setting of MRSA bacteremia.

Methods
A retrospective chart review of adult patients (≥ 18 years of age) admitted to University Health from January 2017 to December 2020 with a diagnosis of MRSA bacteremia was performed. Patients received either CPT monotherapy or DAP-CPT combination therapy for a minimum of 48 hours during their course of therapy.

Results
Thirty-two patients met inclusion criteria and were evaluated. Primary source of infection was pulmonary in the CPT monotherapy group (n=7/24; 29.2%) and osteomyelitis in the DAP-CPT combination group (n= 4/8; 50.0%). Median duration of bacteremia was 8 days and 9 days in the CPT monotherapy and DAP-CPT combination group, respectively. Microbiological cure was achieved in 95.8% (n=23/24) of patients in the CPT monotherapy and 100% (n=8/8) of patients in the DAP-CPT combination group. Bacteremia relapse (30 day, p=0.62; 60 day, p=0.63), readmission rates (30 day, p=0.62; 60 day, p=0.63), and mortality rates (30 day, p=0.70; 90 day, p=0.85) were similar in both groups. There was no statistically significant difference in safety parameters, including incidence of acute kidney injury (p=1.00) and creatine kinase elevations (p=1.00). Bone marrow suppression after at least 72 hours of therapy, including anemia, leukopenia, and thrombocytopenia, was also not statistically significant between groups.

Conclusion
This study was unable to find a statistically significant difference in clinical outcomes between patients receiving CPT monotherapy or DAP-CPT combination therapy. A large prospective, randomized controlled trial to assess CPT monotherapy and DAP-CPT combination therapy for the treatment of persistent MRSA bacteremia is warranted.

Disclosures
All Authors: No reported disclosures
206. Clinical and Molecular Characteristics of Community-associated Staphylococcus aureus Bacteremia in Injection and Non-injection Drug Users at a New York City Medical Center
Authors: Shoucri Sherif , Gomez-Simmonds Angela , Lankarani Amir , Shi Qiuhu , Lowy Franklin D , Uhlemann Anne-Catrin 
Published: December 2021

Abstract

Background
The opioid epidemic has resulted in a dramatic resurgence of bacterial infections, most notably those due to Staphylococcus aureus (SA). We compared the demographic, clinical, and molecular factors of injection drug users (IDUs) and non-IDUs with SA bacteremia.

Methods
Patients with SA bacteremia were identified through a query of the electronic medical record EMR from January 2018 to December 2019 at a New York City medical center. All cases of community-associated (CA) SA bacteremia among adults with a history of active injection drug use were evaluated. Patients with positive SA blood cultures ≤ 72 hours of admission were considered CA. IDUs were identified with keyword searches and were deemed active if they had a history of use in the 12 months prior to admission. A randomly selected group of non-IDUs with CA SA bacteremia was used for comparison at a 4:1 ratio. Available SA isolates underwent Illumina whole genome sequencing (WGS). Using SRST2 multilocus sequence types (MLST), antimicrobial resistance genes and putative virulence factors were extracted.

Results
From January 2018 to December 2019, 669 patients with SA bacteremia were identified. 29 patients were active IDUs. Compared to 112 randomly selected non-IDUs, IDUs were significantly younger and more likely to be unstably housed (Table 1). Rates of MRSA were similar in IDUs (31%) and non-IDUs (32.1%). Endocarditis (44.8% vs 11.6%) and abscesses (27.6% vs 8.9%) were diagnosed more frequently in IDUs than non-IDUs. A positive hepatitis C antibody was strongly associated with SA bacteremia in IDUs (62.1% vs 6.3%, p&lt; 0.001). WGS demonstrated comparable proportions of sequence types across IDUs and non-IDUs. ST8 accounted for the majority of infections in both groups (Table 2). MRSA bacteremia due to ST8 occurred in a higher proportion of IDUs (7/29, 24.1%) than non-IDUs (14/112, 12.5%).

Conclusion
IDUs with CA SA bacteremia have unique demographic and clinical features that differentiate them from non-IDUs. Endocarditis rates in IDUs are of particular concern. Use of these risk factors could allow hospitals to rapidly identify IDUs and offer them necessary medical and social services. WGS revealed a majority of MRSA bacteremia was due to one sequence type in IDUs (ST8). Further analysis of virulence genes in this cohort are ongoing.

Disclosures
Franklin D. Lowy, MD, GlaxoSmithKline (Advisor or Review Panel member)UpToDate (Other Financial or Material Support, Topic Writer and Editor) Anne-Catrin Uhlemann, MD, PhD, Merck (Grant/Research Support)