bluuebunny/crossref_metadata_2025_split huggingface dataset:
427. Trends in Hospital-onset Escherichia coli Infections Resistant to Fluoroquinolones and Extended-spectrum Cephalosporins, 2012-2020
Authors: Hood Nicole , Wolford Hannah , Olubajo Babatunde , Rose Ashley , Baggs James , Reddy Sujan 
Published: December 2022

Abstract

Background
Inpatient and outpatient fluoroquinolone (FQ) use has decreased substantially in the last decade; however, the impact of this trend on FQ resistance is less clear. During this period, extended-spectrum β-lactamase (ESBL) Escherichia coli infections have increased. We examined hospital-onset (HO) E. coli clinical culture trends and resistance patterns among hospitalized adult patients in the United States.

Methods
We measured the incidence of positive clinical cultures from inpatient encounters in a cohort of hospitals submitting data to the Premier Healthcare Database from 2012-2020. We included E. coli cultures with susceptibility testing to FQs or extended-spectrum cephalosporins (ESC). ESC resistance was defined as non-susceptibility to cefotaxime, ceftriaxone, ceftazidime, or cefepime and FQ resistance as resistance to ciprofloxacin, levofloxacin, or moxifloxacin. Co-resistance was defined as both ESC and FQ resistance in the same E. coli isolate. Isolates were classified as FQ resistant only (and not ESC), ESC resistant only (and not FQ), co-resistant, or neither FQ nor ESC resistant.

Results
The overall proportion of HO E. coli with any FQ resistance decreased 12.3% (from 36.7% in 2012 to 32.2% in 2020). The proportion of HO E. coli with only FQ resistance decreased by 39.8% (from 27.9% in 2012 to 16.8% in 2020); the proportion with only ESC resistance increased by 112.5% (from 2.4% to 5.1%), and co-resistance increased by 75.0% (from 8.8% to 15.4%) (Figure). Figure.Proportion of hospital-onset E. coli infections with selected antibiotic resistance patterns, 2012-2020

Conclusion
These results suggest that declining FQ use has been accompanied by declining FQ resistance in E. coli. Increases in FQ and ESC co-resistance may be due to factors including increases in the use of non-FQ antibiotics such as cephalosporins and increased transmission of E. coli strains such as ST131 in which co-resistance is prevalent. Antibiotic stewardship across multiple antibiotic classes combined with infection control measures are likely necessary to reduce multidrug resistant E. coli infections.

Disclosures
All Authors: No reported disclosures.
428. Deep-Learning Based Predictive Model for Patients with Positive MRSA Cultures Using Time-Series Electronic Health Records
Authors: Nigo Masayuki , Rasmy Laila , Xie Ziqian , Septimus Edward J , Zhi Degui 
Published: December 2022

Abstract

Background
Methicillin-resistant Staphylococcus aureus (MRSA) is one of the common pathogens leading to significant morbidity and mortality in the hospital. This pathogen requires specific empirical antibiotics. Hence, identifying the personalized risks of this pathogen likely optimizes the usage of those antibiotics. Deep-learning based (DL) models are shown to be useful for modeling time-series electronic health record (EHR) data, and thus offering potential for predicting individualized risk for MRSA infection.

Methods
Longitudinal data were retrospectively retrieved from EHR in Memorial Hermann System, Houston, Tx. Patient encounters, demographics, diagnostic & procedure codes, antibiotics use, and microbiology data were extracted between 1/2018 and 4/2021. Inpatient and outpatient data were included. We randomly identified roughly equal numbers of patients with positive culture (Cx) for MRSA, MSSA, other pathogens, and negative Cx. We set a 2-week window for the prediction, and any first culture within the window was used as an index Cx. Some patients had multiple predictions over time and were included into both MRSA vs. non-MRSA groups. Our team developed a DL model platform (Pyorch_EHR) for clinical outcomes predictions using structured EHR data. In this project, the outcome is MRSA positivity taken within 2 weeks from the index Cx. Datasets are split into 50, 30, and 20% for training, validation, and test, respectively. Other machine learning models; logistic regression (LR) and light GBM (LGBM) were used for comparison. Pytorch ver. 1.7.1 and Sklearn ver. 0.24.2 are used.

Results
A total of 8164 patients and 22,563 patients were identified as MRSA and non-MRSA groups, respectively. Table 1 summarizes the key features of the patient’s characteristics. After model training using train and validation datasets, our model achieved an AUC of 91.8 in test dataset, whereas AUC of 86.0 and 88.2 in LR and LGBM, respectively. Figure 1 shows the cumulative incidence of 2 week MRSA positivity. Our model precisely stratified the risks. Figure 1:Cumulative Incidence of Positive MRSA Cultures Based on Risk Stratificationa

Conclusion
Our DL based model exhibited excellent performance in the prediction of 2 week MRSA positivity. Our model precisely categorized patients into low, medium, and high-risk. This work should be validated with other data sources and high-risk subgroups.

Disclosures
All Authors: No reported disclosures.
431. Screening and Targeted Staphylococcus aureus Decolonization of Acute and Intensive Care Patients and Invasive Infections in an Academic Medical Center
Authors: DiTullio David J , Takats Courtney , Hochman Sarah 
Published: December 2022

Abstract

Background
Staphylococcus aureus is a common cause of healthcare associated infections and is associated with high mortality. Universal S. aureus decolonization reduces methicillin-resistant S. aureus (MRSA) and other bloodstream infections among ICU patients. However, universal decolonization in acute care settings has not shown a similar benefit. We describe a screening and targeted decolonization protocol implemented at an academic hospital across acute and intensive care settings. The goal of this study was to assess the impact of decolonization on rates of S. aureus invasive infections.

Methods
Adult Medicine, Oncology, Transplant, and ICU patients were screened by nasal swab for S. aureus colonization on admission and change in level of care. Colonized patients received 5 days of chlorhexidine 2% applied to the body and mupirocin for the nares. We compared decolonized patients with patients who received no decolonization. The primary outcome was S. aureus invasive infection from hospital day 5 until discharge, defined by positive cultures from sterile sites. Secondary outcomes included 30-day readmission and 30-day mortality.

Results
Between 2018-2020, 3,835 (23%) out of 16,467 hospitalized patients screened positive for MSSA (74%) or MRSA (26%). Among colonized patients, median age was 67 years (interquartile range [IQR] 54-79) and median LOS was 6 days (IQR 4-11). Among patients with LOS ≥ 5 days, 977 (37%) received decolonization. There were 122 invasive infections, 56 (46%) occurring in patients who received decolonization. Wound infections were most common (28; 23%), followed by bacteremia (27; 22%). In multivariate regression analysis controlling for confounding factors including comorbidities and length of stay, decolonization was not significantly associated with incident invasive infections (p = 0.395).

Conclusion
We report on a S. aureus screening and targeted decolonization program; our initial analyses do not demonstrate an association between decolonization and reduced invasive S. aureus infections. Further investigations will examine subsets of high-risk patients and transmission events to assess if specific populations may benefit from this program.

Disclosures
All Authors: No reported disclosures.
432. Ward-level Variation in Transmission of MRSA in Veterans Affairs Hospitals
Authors: Khader Karim , Stevens Vanessa W , Thomas Alun , Toth Damon , Keegan Lindsay T , Rubin Michael , Samore Matthew H 
Published: December 2022

Abstract

Background
In 2007, the Department of Veterans Affairs (VA) implemented the methicillin-resistant Staphylococcus aureus (MRSA) Prevention Initiative nationally in acute care facilities (ACFs). Since that time, numerous publications have reported declining transmission rates and infection rates due to MRSA across the VA. Recent estimates of the impact of contact precautions (CP) on transmission suggest that the infectiousness of patients while on CP was 50% lower than patients not on CP. We extend that work by estimating the variation and trend in transmission while accounting for the estimated impact of CP on transmission.

Methods
We analyzed ten years of data from 108 VA ACFs from 1/1/2008 – 12/31/2017 using a Bayesian transmission model. The data included admission, discharge, and surveillance and clinical test results for MRSA. Data were partitioned into five 2-year analysis periods to allow for estimates of transmission to change over time, including all facilities with complete data spanning the 10-year study period. We estimated person-to-person transmission rates for each ward assuming the classic mass-action transmission framework, while accounting for the impact of CP on transmission, and used random effect models with inverse variance weights to derive pooled estimates of the transmission rates and trends across ward-types and over time.

Results
In this cohort study of 108 VA hospitals during the 10-year period, more than 2 million unique individuals had over 5.6 million admissions with more than 8.4 million MRSA surveillance tests (9.3% of which were positive). We observed a decline in the overall transmission rate over time, with the reduction driven by declining rates of transmission in the ICU setting (Figure 1). We observed that the transmission rate in medical/surgical wards remained constant during the 10-year period.
Transmission trend by ward

Conclusion
We observed that in addition to the two-fold reduction in transmission of MRSA associated with CPs, that over the study period, the transmission rate declined in VA hospitals driven largely by reductions in the ICU setting. The secular trend downward in ICUs might reflect improved hand hygiene, changes in antibiotic use, or enhancements to other infection control practices. Additional work is needed to better understand and identify these factors.

Disclosures
Karim Khader, PhD, BioFire Diagnostics: Grant/Research Support.
439. Anal Dysplasia Screening Cascade within a Single-Center Outpatient HIV Clinic
Authors: Modlin Chelsea , Rockney Danica , Cherian Jerald , Zhong Diana , Krishnan Sonya , Karanika Styliani , Jones Joyce 
Published: December 2022

Abstract

Background
HIV-positive men who have sex with men (MSM) are recommended to have anal Pap tests annually to screen for high-grade anal squamous intraepithelial lesions (HSIL). In this population, removal of HSIL reduces the risk of progression to anal cancer. This study aims to assess the effectiveness of the anal dysplasia screening cascade in a single-center outpatient clinic.

Methods
We conducted a single-center retrospective cohort study at Johns Hopkins. All adult HIV-positive MSM patients who had in-person encounters in the Bartlett Clinic between October 1, 2019-April 30, 2021 were included. Clinical information and dates of anal pap smears and HRAs were provided via an Epic data extraction. Manual chart review was conducted for anal pap and HRA pathology results. Descriptive analysis was performed. The primary outcome was successful navigation of the institutional anal dysplasia screening cascade, defined as annual anal Pap testing and completion of HRA if pap results were abnormal. This study was IRB exempt.

Results
779 HIV-positive MSM patients were seen for in-person visits during the study period. 24% (190/779) of patients underwent at least one screening anal Pap, with 29 having multiple anal pap smears leading to a total of 219 anal pap smears done. 40% (87/219) were abnormal. Among those with an abnormal pap, 72% (63/87) had a referral for HRA placed but only 26% (23/87) underwent HRA. 39% (9/23) of HRAs identified HSIL in patients with lower-grade lesions on Pap test and one patient with HSIL on Pap had anal cancer detected on HRA. In total, 120 patients navigated the anal cancer screening cascade appropriately. This compromised 15% (120/779) of eligible MSM patients seen for at least one in-person clinic visit and 63% (120/190) of patients who underwent an anal Pap.

Conclusion
Completion of a screening cascade for anal dysplasia among HIV-positive MSM at our clinic was low. The largest gaps were seen in initiating annual anal Pap screening and scheduling referrals for HRA in surgical subspecialty clinics. Increased attention and clinic resources should be directed toward narrowing these gaps to ensure HSIL and anal cancers are detected early within this high-risk population.

Disclosures
All Authors: No reported disclosures.
470. Changing Urgent Care Patterns of Diagnosing Coccidioidomycosis in a Highly Endemic Urban Population
Authors: Pu Jie , Miranda Valerie , Minior Devin , Raynolds Shane , Rayhorn Benjamin , Galgiani John N 
Published: December 2022

Abstract

Background
We found previously (Pu et al. Clin Infect Dis, 2021: PubMed 32511677) that only 0.2% of ICD10 codes for coccidioidomycosis (CM) in our health care system were associated with patients (pts) managed at an urgent care (UC) visit. Since 2020, during onboarding, at quarterly meetings, and in periodic emails, UC clinicians were encouraged to test for CM in patients with pneumonia (PNA).

Methods
For 2018 through 2021, Banner Health UC System increased clinics from 41 to 48, clinicians from 89 to 193 (Nurse Practioners, 49.2% ± 2%, Physician Assistants, 39% ± 2%, MDs/DOs 13% ± 1%), and total visits from 787 to 1,290 thousand. Average visits were 1.6 per pt. All UCs used a common electronic medical record (Cerner) during the study period. Data were downloaded in January 2022 to analyze UC clinician patterns of coccidioidal serologic testing (CST, 98% were EIAs), CST results, and their relation to ICD10 codes.

Results
For the study period, CST orders increased from 8.0 to 19.0 per 10,000 UC visits (chi-squared p&lt; 0.001). The percent of clinics testing &gt;10 per year increased from 16% to 78%, and the percentage of clinicians testing increased from 37% to 67%. Percent positive CSTs were highest for August, November, and December (27.4%) and lowest from April through July (8.1%). PNA ICD10 codes (J18.9 or J18.1) were most frequently associated with positive CSTs (374 positive of 1,872 tested), and the ICD10 code for Erythema nodosum (EN, L52, 176 total pts) had the highest positivity rate (61.4%, 27 positive of 44 tested). Only 6 pts had both EN and PNA codes. As indicated in the table, testing of PNA pts over time increased on first visits, decreased on second visits, and increased on second visits when the first CST was negative. Testing also increased for EN pats. Despite these favorable changes, CST was still not done on over three quarters of pts where recommended.
Coccidioidal serologic testing in urgent care clinics by month for 2018-2021. Open circles are percentage of total visits that involved a test; closed squares are percentage of tests that are positive.

Conclusion
Routine quality improvement activities have significantly but only partially improved rates of testing pts with PNA or EN for CM in UC clinics located in an endemic area. Innovative strategies to change clinical practices may be needed to achieve greater success.

Disclosures
All Authors: No reported disclosures.
473. Diabetes Mellitus as a Risk Factor for Cryptococcosis — a Multicenter Research Network Study
Authors: Kung Vanessa , Henao-Martínez Andrés F , Tagawa Alex , Kennis Matthew , Franco-Paredes Carlos , Vargas Barahona Lilian , Shapiro Leland , Chastain Daniel B 
Published: December 2022

Abstract

Background
Diabetes mellitus type 2 (DM2) is a common medical condition that increases the risk of bacterial infections, and is often present in patients with cryptococcosis. The role of DM2 as an independent risk factor for cryptococcosis is debatable. We aim to better characterize the natural history of cryptococcosis in patients with DM2 as their only comorbidity.

Methods
We utilized TrinetX, a federal national network, to identify HIV-negative patients who had cryptococcosis without known risk factors. Demographic characteristics and outcomes were compared between patients with DM2 and those without DM2, who tested positive or had ICD based diagnoses of Cryptococcus infection within five years of diagnosis of DM2.

Results
Sixty patients with DM2 (as the sole risk factor) and 707 patients without DM2 had cryptococcosis. Patients with DM2 and cryptococcosis were older (61 ± 13.6 years vs. 55.8 ± 16.2 years, p=0.0219), and more likely to be Hispanic or Latino (18% vs. 9%, p=0.023). They had higher rates of hypertension (77% vs 44%, p&lt; 0.0001), cystic fibrosis (18% vs 1%, p&lt; 0.0001), tuberculosis (18% vs 1%, p&lt; 0.0001), and chronic kidney disease (33% vs 18%, p=0.0026). The mean HbA1c among patients with DM2 who developed cryptococcosis was 8.16 (SD 2.62). The most common sites of cryptococcus infection were pulmonary (56% vs 55%, p=0.8930) and cerebral (36% vs 40%, p=0.5589), in both groups. The two groups had similar mortality (20% vs 25.47%, p=0.3676) (Figure 1), and hospitalization rates (20% vs 31.3%, p=0.08). The overall annual cryptococcosis risk among HIV-negative patients with DM2 without any additional risk factors was 0.001%.

Conclusion
Cryptococcosis occurs rarely in HIV-negative patients with DM2 and without additional risk factors. Hispanic or Latino ethnicity, uncontrolled hyperglycemia, and chronic kidney disease may increase the risk of cryptococcosis among patients with DM2. Cryptococcosis in patients whose only comorbidity is DM2 have as high of mortality as that seen with more established comorbitidies.

Disclosures
All Authors: No reported disclosures.
474. Differences In Clinical Manifestation, Prognostic Factors, and Outcomes Between Patients With Community-onset And Nosocomial Candidemia
Authors: Chen Yung-chun , Chang Chao-chin 
Published: December 2022

Abstract

Background
Candidemia is an invasive and deadly infectious disease. The associated risk factors of candidemia include immunosuppression, broad-spectrum antibiotics, catheters, glucocorticoids, critical illness, surgery, neonates, previous candida colonization, and illicit drug use. In previous studies, the characteristic of community-onset candidemia was distinct from nosocomial candidemia.

Methods
We selected patients who were admitted for equal or more than two days in Taichung Veterans General Hospital of Taiwan from 2015 to 2018 with electronic medical charts. The diagnosis of candidemia was defined as Candida species identified in blood cultures by commercial identification systems. We applied Kaplan-Meier survival curves with a log-rank test and built multivariate Cox proportional-hazards models for risk factors associated with in-hospital mortality. The purpose of this study is to investigate the difference in the characteristics, outcomes, and associated risks of death between community-onset and nosocomial candidemia.

Results
A total of 339 patients were included for analysis. The incidence was 1.50 per 1000 admission person-years. 64.60% of patients were male, and the mean age was 64.24-year-old. The characteristics of patients were similar in both groups except for the status of port-A, glucocorticoid usage, and diabetes mellitus. In the community-onset group, a higher proportion of C. glabrata and C. parapsilosis, but fewer C. albicans and C. tropicalis were identified than in the nosocomial group. The all-cause mortality rate was 55.75%. Multivariate Cox proportional-hazards model showed that nosocomial (hazard ratio; HR, 1.96; 95CI, 1.291 - 2.97 ; p =0.002), glucocorticoids within seven days before candidemia (HR, 1.68; 95CI, 1.21 -2.32, p = 0.002), and septic shock (HR, 1.85; 95CI, 1.292 - 2.641, p &lt; 0.001) were associated with poor outcome whereas treatment with an echinocandin within two days after candidemia was a protective factor (HR, 0.65; 95CI, 0.466 - 0.911, p = 0.012).
Survival curves analysis between community-onset candidemia and nosocomial candidemia
A log-rank test was applied to assess the statistical significance, and a p-value less than 0.05 was considered statistically significant.

Conclusion
In conclusion, candidemia is a lethal disease with a better outcome noted in those with community-onset candidemia. Species diversity existed in both groups, and Early initiation of echinocandin therapy within two days could reduce 35% mortality.

Disclosures
All Authors: No reported disclosures.
481. Risk Factors and Clinical Outcomes of Candidemia Associated with Severe Coronavirus Disease 2019 (COVID-19)
Authors: Bhowmick Tanaya , Jagpal Sugeet , Varughese Tilly , Patel Purvi , Jen Polly , Maxwell Tyler , Tatem Luis , (Claudia) Choi Seohyun , Walker Amanda , Eidensohn Yehuda , Smoke Steven , McCracken James A , Cardinale-King Maria , Haribhakti Aditi , Cani Eris , Dixit Deepali 
Published: December 2022

Abstract

Background
COVID-19 can cause serious illness requiring multimodal treatment of the viral infection and its associated complications, including the potential for secondary infections. Studies have suggested an increased risk of fungal infections, including candidemia following severe COVID-19 though understanding of risk factors and clinical outcomes remains unclear.

Methods
A multi-center, case-control study of patients with severe COVID-19 was conducted to evaluate risk factors and clinical outcomes in patients who developed candidemia between August 2020 to August 2021. Risk factors associated with candidemia and mortality were characterized using multivariate analyses.

Results
A total of 275 patients were enrolled in the study, including 91 patients with severe COVID-19 and subsequent candidemia and 184 patients with severe COVID-19 without candidemia. Most patients received antibiotics prior to candidemia episode (93%), while approximately one-quarter of all patients received biologic for COVID-19. In-hospital mortality was significantly higher in the case group compared to the control group (68% vs 40%, P &lt; 0.01). Multivariable logistic regression revealed that the use of central lines, biologic and paralytic therapy were independent risk factors for candidemia. The presence of candidemia, older age, central line use, and intensive care unit admission were significantly associated with mortality.
Demographics and Baseline Characteristics of Study Patients with SARS-CoV-2 Positive With or Without Candidemia
Hospitalization Details and Outcomes

Conclusion
Clinicians should be aware of the possibility of development of candidemia in hospitalized older patients with severe COVID-19 and should closely monitor those patients at risk. Risk factors for developing candidemia in the setting of COVID-19 are largely consistent with classic risk factors previously identified.

Disclosures
Tanaya Bhowmick, MD, Gilead: Grant/Research Support|Shinogi: Advisor/Consultant Steven Smoke, PharmD, BCPS, BCIDP, Karius: Advisor/Consultant|Shionogi: Advisor/Consultant.