bluuebunny/crossref_metadata_2025_split huggingface dataset:
2956. Increased Microbiota Alpha Diversity is Associated with Decreased Hospital Mortality in Medical Intensive Care Unit Patients
Authors: Sansom Sarah E , Bassis Christine , Schoeny Michael , Thotapalli Lahari , Fukuda Christine , Dangana Thelma E , Bongu Jahnavi , Jaskowiak Anne , Bekele Selamawit , David Michael Z , Dubberke Erik R , Young Vincent B , Hayden Mary K 
Published: November 2023

Abstract

Background
Characteristics of the gut microbiome may be useful to predict resistance to colonization and expansion of pathogenic organisms such as C. difficile. In this study, we evaluated whether inclusion of microbiome characteristics improved a clinical prediction model for in-hospital mortality.

Methods
Rectal or fecal swab samples were collected daily from medical intensive care unit (ICU) patients from three hospitals between 2017-2019 and underwent 16S rRNA gene sequencing of the V4 region. Patient admissions with ≥1 rectal swab collected &lt; 48hrs from ICU admission were randomly selected 2:1 for calibration and validation analyses. Independent variables included Shannon Index, Microbiome Health Index, Community Type (CT) and relative abundance (RA) of specific bacterial taxa based on 3% sequence difference or class-level classification. The RA of each bacterial taxon was range-standardized (95%) and scaled to analyze a 10% relative difference within each taxon’s range. Logistic regression models identified microbiome characteristics at admission that were associated with in-hospital mortality. Fixed effects were included in all models to account for microbiome differences between facilities.

Results
There were 1365 patient admissions (910 calibration, 455 validation) analyzed (Table), of which 134 (96 calibration, 38 validation) died during hospitalization. Increase in Shannon Index by 1 [OR 0.66 (0.51-0.84), p=0.001], 10% relative increase in the RA of Bacilli [OR 1.15 (1.08-1.22), p&lt; 0.001] and 10% relative increase in the RA of Enterococcus [OR 1.10 (1.04-1.14), p=0.001] were associated with in-hospital mortality in calibration models after controlling for Charlson Comorbidity Index [OR 1.23 (1.15-1.32), p&lt; 0.001]. Increase in Shannon Index by 1 [OR 0.88 (0.57-1.38), p=0.581] had the same direction and similar odds in the validation cohort (Figure), supporting the findings of the calibration model.

Conclusion
In this secondary analysis of a large, multicenter, prospective medical ICU cohort, we found that higher alpha diversity of the gut microbiome was associated with decreased odds of in-hospital mortality.

Disclosures
Michael Z. David, MD PhD, Covance: Grant/Research Support|GSK: Advisor/Consultant|GSK: Grant/Research Support Erik R. Dubberke, MD, MSPH, Abbott: Advisor/Consultant|AstraZeneca: Advisor/Consultant|Ferring Pharmaceuticals: Advisor/Consultant|Ferring Pharmaceuticals: Grant/Research Support|Merck and Co.: Advisor/Consultant|Pfizer: Advisor/Consultant|Pfizer: Grant/Research Support|Seres Therapeutics: Advisor/Consultant|Summit: Advisor/Consultant|Theriva Biologics: Grant/Research Support Vincent B. Young, MD/PhD, ASM: Senior Editor|Debiopharm: Advisor/Consultant|Vedanta Biosciences: Advisor/Consultant
2331. Characteristics Associated with Hospital-Acquired COVID-19 Infections in Los Angeles County
Authors: Sato Heidi D , OYong Kelsey , Rubin Zachary 
Published: November 2023

Abstract

Background
Few studies have characterized nosocomial transmission of SARS-CoV-2. We examined factors associated with hospital-acquired infections (HAIs) rates for SARS-CoV-2 in Los Angeles County (LAC).

Methods
In this retrospective cohort study, data were collected from 70 acute care hospitals between July 1, 2020 and March 31, 2022. We defined COVID HAIs as a patient with laboratory-confirmed SARS-CoV-2 (PCR or antigen test), which was first positive 4 or more days after hospital admission and before discharge. Community transmission (CT) level was calculated by dividing new cases within the past 7 days by the population in the county (per 100,000). Variant predominant periods were defined as periods when the variant exceeded 50% of sequenced specimens during the specimen collection month. The percent of core healthcare personnel (HCP) receiving a completed COVID vaccination series (as of 11/28/2021) was obtained from the National Healthcare Safety Network (NHSN). Incidence rates were calculated using patient-days as a denominator, as reported to NHSN. Mantel-Haenszel test was performed to assess COVID HAIs and predominant variant periods, controlling for effect of CT level. We analyzed hospital characteristics associated with incidence rate using multiple regression (SAS 9.4).

Results
During the 21-month study period, 2107 patients were identified as having COVID HAIs at 70 hospitals using the standardized definition. COVID HAIs were more likely to occur during high CT levels (RR=6.2; 95% CI=4.9, 8.0) and when the Omicron variant was predominant (RRCMH = 1.2; 95% CI=1.1, 1.4). In multivariate analysis, a higher rate of COVID HAIs was associated with hospitals unaffiliated with medical schools (β= -30.9, p&lt; .05), lower HCP vaccination coverage (β= -0.6, p&lt; .05), more hospital beds (β= 0.1, p&lt; .05), and ownership type (β= 19.2, p&lt; .01). In comparison to government hospitals, HAIs were three times more likely to occur in for-profit hospitals (95% CI=2.6, 3.6) and 1.4 times more likely to occur in not-for-profit hospitals (95% CI=1.2, 1.7).

Conclusion
COVID HAIs are more likely to occur during high transmission periods and at hospitals without medical schools, with for-profit ownership, lower HCP vaccination rates, and with a higher number of beds.

Disclosures
All Authors: No reported disclosures
127. Evaluation of Real-Time Verigene Blood Culture Alerts on Time to Optimal Antibiotic Therapy
Authors: Adams David T , Kaur Satwinder S 
Published: November 2023

Abstract

Background
Verigene blood culture (VBC) results can help facilitate reductions in time to optimal antimicrobial therapy (TTOT), potentially leading to improved clinical outcomes. We sought to evaluate if TTOT could be further reduced by implementing automated real-time VBC alerts delivered to the antimicrobial stewardship (AMS) team.

Methods
A retrospective observational cohort study of adult patients with bacteremia and a VBC result from May to September 2021 comparing outcomes when alerts resulted while AMS team members were working compared to not working. AMS team members review all positive blood culture alerts and make recommendations to the treating physicians based on results and current antimicrobial regimens. Excluding patients with a VBC result of Staphylococcus species, Streptococcus species, S. epidermidis, or no target detected, patients with an opportunity for change in their empiric antimicrobial regimen based on the VBC result were included.

Results
In total, 207 patients met inclusion. The most frequent organisms encountered with an opportunity for intervention were E. coli (n=92) and S. aureus (n=49). The most common source was urinary (37.2%). Mean TTOT was shorter in the VBC+AMS group (41.4 hours) compared to the VBC only group (53.1 hours) regardless of whether the AMS team recommendation was accepted, P = .035. This difference was unsurprisingly larger when evaluating only those in the VBC+AMS group where the recommendation was accepted (18.9 hours) compared to all other patients (54.6 hours), P = &lt; .0001. All-cause in-hospital mortality was significantly lower in the VBC+AMS group (12.3%) compared to the VBC only group (26.9%), P = .02. Similar rates of change to optimal therapy at any point during the admission (91%) were observed in the VBC only and VBC+AMS groups.

Conclusion
The implementation of a real-time alert system to communicate VBC results to the AMS team resulted in a significant reduction in TTOT and in-hospital mortality when alerts occurred while AMS team members were working. Given the high antibiotic optimization rates in both groups but a difference in mortality, further studies are needed to identify if there is an association between TTOT and improved clinical outcomes beyond the benefits of timely effective antimicrobial therapy.

Disclosures
All Authors: No reported disclosures
2389. Surveillance evaluation of COVID-19 pharmacovigilance—Karakalpakstan, Uzbekistan, 2022
Authors: Tursinov Yunis , Kurbanov Botirjon , Denebayeva Alfiya , Horth Roberta , Nabirova Dilyara 
Published: November 2023

Abstract

Background
COVID-19 vaccines are safe and effective. Rapid rollout of vaccines reduced COVID-19 morbidity and mortality globally. Pharmacovigilance systems have ensured safety of these vaccines. Well-functioning vaccine safety surveillance builds public confidence in vaccine programs, but these systems may be lacking in limited-resource settings. To identify gaps in pharmacovigilance surveillance, we conducted an evaluation in Khojaly District, Uzbekistan, with population of 120 thousand people.

Methods
We reviewed regulatory documents related to COVID-19 vaccination and registration of side effects after immunization. We also conducted a survey in April 2022 of 30 healthcare providers in 5 of 10 polyclinics in Khojaly districts whose responsibilities included vaccination of the population. The survey asked about their knowledge and practices related to adverse events following immunization (AEFI). AEFI was defined as any health condition that occurs after immunization and does not necessarily have a causal relationship with vaccination.

Results
From April 2021 to March 2022, 78,453 doses of COVID-19 vaccines were given in Khojaly district. Of these, 70% of doses were from ZF-UZ-VAC-2001 (Zifivax) vaccine doses, an adjuvanted protein produced in Uzbekistan (Table 1), 9% Pfizer–BioNTech vaccine doses and 7% Moderna vaccine doses. All AEFIs are mandatorily reported by providers (Figure 1). Of 2,464 reported AEFI, majority (75%) were procedural errors, 1% were mild allergic reactions, and only 2 cases of anaphylactic shock. Among healthcare providers surveyed (Table 2), 33% did not know where to report the AEFI and 10% reported large patient load as a barrier to reporting. Half (50%) of providers had encountered a case of AEFI following COVID-19 vaccination, 10% encountered a severe AEFI, and 43% submitted an AEFI report. In record review, we identified cases of AEFI that had only been registered in patient medical charts, and not reported into the AEFI surveillance system.
Diagram of AEFI surveillance for COVID-19 vaccines in Uzbekistan
COVID-19 vaccine doses and reported AEFI, Khojaly district, Uzbekistan, 2021-22
Knowledge of AEFI and AEFI reporting among COVID-19 vaccine providers, Khojaly district, Uzbekistan, 2021-22

Conclusion
Important considerations were identified in COVID-19 pharmacovigilance surveillance. The system can be strengthened through increased training of healthcare providers in standard operating procedures for identifying, reporting and investigation AEFI cases associated with COVID-19 vaccines.

Disclosures
All Authors: No reported disclosures
2397. Infective Endocarditis is Associated With Higher Mortality and Worse Clinical Outcomes in Patients Hospitalized with a Concomitant Diagnosis of Heart Failure
Authors: Sharath Deepali Boothankad , Khokhlov Leonid , Fatuyi Michael , Patel Anar 
Published: November 2023

Abstract

Background
The United States has the highest incidence of infective endocarditis (IE) in the world at 15 per 100,000 people with increasing incidence due to the aging population and growing rates of intravenous drug use (IVDU). Heart failure (HF) is the most common complication and the main cause of death in patients with IE. There is limited evidence on the clinical outcomes in IE populations affected by HF. We sought to investigate the demographics and outcomes of this cohort of patients.

Methods
The Nationwide Inpatient Sample (NIS) database was queried between 2017-2020 for adult patients who were hospitalized with the primary diagnosis of IE. The secondary diagnosis was HF. The primary outcome evaluated was inpatient mortality. The secondary outcomes were severe sepsis, septic shock, cardiogenic shock, cardiac arrest, invasive mechanical ventilation, length of stay (LOS), and total hospital charge. Multivariable logistic and Poisson regression analyses were used to estimate clinical outcomes. P-value &lt; 0.05 was significant.

Results
We identified a total of 250,070 hospitalizations with the diagnosis of IE in 2017-2020, 95,320 of which also had HF (38%), 45% of which with specified systolic heart failure. Patient characteristics are shown in Table 1. Patients admitted with IE and concurrent HF had significantly higher inpatient mortality and worse clinical outcomes. (Table 2 and Figure 1).

Figure 1
Clinical Outcomes in Patients with IE and Concomitant HF

Conclusion
Our study showed that patients with IE and concurrent HF tended to be older males, Caucasians, and obese. This cohort was more likely to have atrial fibrillation, diabetes mellitus, dyslipidemia, acute coronary syndrome, ST elevation MI, acute renal failure, and chronic kidney disease (Table 1). Hence, cardiac dysfunction in IE patients is associated with renal and pulmonary impairment, higher rates of infectious complications, and a more severe hospitalization course. This can be explained by the myocardial dysfunction that predisposes to end-organ damage. When managing patients with IE and co-existing HF, clinicians should be aware of this predictor of negative outcomes. Further studies are necessary to describe the more recent trends given better antibiotic therapy, control of IV drug use, and earlier surgical interventions.

Disclosures
All Authors: No reported disclosures
2398. Short and Long-Term Outcomes of Patients Admitted with Infective Endocarditis Who Undergo Patient-Directed Discharge
Authors: Crooker Kyle , He YuTing , Hickey Tess , HoddWells Max , Sarathy Ashwini , Teng Torrance , Muniz Sean , Lor Jennifer , Chang Amy , Tompkins Bradley , HALE A N D R E W 
Published: November 2023

Abstract

Background
Infective endocarditis (IE) results in high morbidity and mortality. Guidelines for IE recommend prolonged intravenous antibiotics that can result in extended hospitalization, but some patients experience patient-directed discharges (PDD) prior to completion. There is a current lack of literature clearly defining long-term outcomes and optimal treatment strategies in patients with IE who experience PDD.

Methods
This is a retrospective cohort study comparing outcomes of adult patients with infective endocarditis at a single center from 2010 to 2020 who experienced patient-directed discharge versus those who did not. The primary outcomes were 30 day, 90 day, and 2 year re-admission and mortality rates related to IE. The secondary outcome was worsened IE, which encompassed pertinent clinical and microbiologic outcomes.

Results
391 patients were identified and included. Of these 47 (12%) experienced PDD and 344 (88%) did not. The PDD cohort was younger (mean age 33.3y (IQR 27.7 to 37.6) vs 60.1y (IQR 37.4 to 72.5 (p&lt; 0.01)); more likely to be on Medicaid (75% vs 29% (p&lt; 0.01)), undomiciled (17% vs 6.4% (p=0.01)), using intravenous drugs (87% vs 27% (p&lt; 0.01)), and have psychiatric comorbidities (53% vs 33% (p&lt; 0.01)). The PDD cohort received a mean of 17.3 days of IV antibiotics vs 36.5 days in the controls (p&lt; 0.01) with 26 (55%) of the PDD cohort getting oral antibiotics upon discharge with an average duration of oral antibiotics of 29.3 days. Compliance on oral antibiotics was low in the PDD cohort (46%). There was no significant difference in death related to IE (0% vs 4% (p=0.3)). 30 and 90 day readmission rates were significantly higher in the PDD cohort (38% and 47% vs 11% and 15% (p&lt; 0.01)). The PDD cohort was significantly more likely to be readmitted with new heart valves involved (21% vs 3% (p&lt; 0.01)), new paravalvular abscess (9% vs 1% (p&lt; 0.01)), different causative organisms (40% vs 18% (p&lt; 0.01)), and/or new metastatic sites of infection.

Conclusion
Adult patients with IE who experience PDD are more likely to be younger, undomiciled, to use intravenous drugs and to have a psychiatric comorbidity. These patients have significantly worse outcomes from IE. Further treatment and outreach strategies in this patient population are essential to improve outcomes.

Disclosures
All Authors: No reported disclosures
2424. Outcomes of vascular graft infections without graft removal treated via OPAT: A retrospective cohort study
Authors: Hennigan Oisin , Geoghegan Laoise , Reynolds Maura , Morrison Elaine , Clarke Susan 
Published: November 2023

Abstract

Background
Vascular graft infections (VGI) are a rare complication of endovascular aneurysm repair (EVAR) with significant associated morbidity and mortality. While surgical removal of infected material may be the preferred treatment, for patients who have inoperable VGIs conservative management with antibiotics may be the only option.
This study aims to investigate the outcomes including mortality, re-admissions, relapse within 12 months, microbiological data, bed days saved, and use of long term suppressive antibiotics in patients with VGI where the graft is retained.

Methods
This single centre retrospective study evaluated all patients with a VGI between 2013-2021 who were treated via OPAT. Patient information was gathered from the local OPAT database and via the patients’ electronic patient records.

Results
23/27 OPAT episodes were managed without graft removal. 52% were male. The median age was 70yrs (range 45-81). Median IV treatment of 6 weeks.
All patients received anti Staphylococcal cover while 14/23 episodes includes anti-MRSA agents.
6/23 episodes required re-admission over the course of OPAT treatment, of which 2 were OPAT related (1 DVT, 1 ADR) while 4 were disease related. 4/23 patients died within the first year of treatment all of which were secondary to their infected graft. In the remaining 19 patients there were no relapses by the 12 month follow up period.
13/16 patients who successfully completed their OPAT course were commenced on long term oral suppression.
32 bed days were saved per OPAT episode, a 77.0% reduction in overall hospital stay.
Type of infection
Pie chart breaking down the types of Vascular Graft Infections affecting the 23 patients included in this case series.
PO Suppressive Abx
Pie chart displaying the PO suppressive antibiotics chosen for the 19 patients who completed OPAT successfully.
Culture results
Bar chart displaying culture results. Sub categories include Gram-positive, Gram-negative, Fungal, Nil positive culture results and number of patients with polymicrobial culture results

Conclusion
Limited data shows mortality associated with VGIs ranges from 25-55%. This study demonstrates successful outcomes in our cohort of patients treated conservatively without surgery but focussed antibiotic therapy long term. It was well tolerated in the OPAT setting after initial stabilisation in hospital and OPAT can be considered a safe option for VGI infections. The small study shows a 1-year survival rate of 82% comparing very favourably with other published data.

Disclosures
All Authors: No reported disclosures
2463. Bacterial Infections in Intensive Care Unit patients in a large general hospital, Kazakhstan, 2022
Authors: Yergaliyeva Ademi , Gazezova Saya , Ayapova Gulzhan , Ibragimova Elvira , Nabirova Dilyara , Horth Roberta 
Published: November 2023

Abstract

Background
Between January and April 2022, an audit of surveillance data revealed five cases of bloodstream Acinetobacter baumannii infection in intensive care unit (ICU) patients in a large general hospital. Bacterial infections such as Acinetobacter baumannii contribute to significant mortality and complications of treatment in ICU patients. We aimed to describe bacterial pathogens and their resistance profile among ICU patients to inform infection prevention and control programs.

Methods
We conducted a cross-sectional study of patients admitted to the ICU of a large general hospital in Kazakhstan from January to April 2022. The study included all patients ≥ 18 years old diagnosed with a bacterial infection as detected in blood, urine or sputum samples. Demographic, clinical, and laboratory data were abstracted from medical records.

Results
Among 65 patients identified, 54% were male, mean age 64 years (range 20-93). Majority (35%) were admitted directly to the ICU, 15% had been transferred to the ICU from the infectious surgery department, 14% from the stroke department, and 5% from the gynecology department. Sixty-eight percent (44/65) of patients had surgery prior to transfer to the ICU. The most frequent pathogen in the study patients was Acinetobacter baumannii 63% (n=41). Of which, 15% was detected in blood, 41% in urine, and 44% in sputum. The hospital only tests for drug-resistance for the prescribed antibiotic, and 63% (26/41) of strains tested were resistant to their prescribed medicines. Klebsiella pneumoniae was detected in 22% (n=15) patients. Of which, 60% was detected in sputum, 20% in urine and 20% in blood. Also, 60% were drug-resistant. Staphylococcus aureus was detected in 11% of patients. Of which, 57% was drug-resistant in sputum. Overall 60% (39/64) of pathogens tested had resistance for the antibiotic prescribed, but there was no evidence that prescribed antibiotics changed based on resistance results.
Antimicrobial resitance and antibiotics prescribed to patients in an ICU of a large general hospital (n=65), Kazakhstan, 2022
Map of bacterial infection in ICU patients admitted from different wards in a large general hospital, Kazakhstan, 2022

Conclusion
The identification of infectious pathogens with demonstrated drug resistance reinforces the need for improved basic infection control practices and the need for improved antimicrobial stewardship. Increased surveillance and reporting of hospital-acquired infections is needed.

Disclosures
All Authors: No reported disclosures