bluuebunny/crossref_metadata_2025_split huggingface dataset:
1204. Assessing Perceptions and Efficacy of COVID-19 Case and Contact Investigations – Dallas County, Texas, 2020
Authors: Serrano Jose , Clouston Harper R , Wiegand Jared , Shim Kyoo , Popper Nathan , Maaraoui Kayla , Limsenben Joshua , Hum Maxwell , Roseman Robert , Gomez Ivorry , Chung Wendy 
Published: December 2021

Abstract

Background
During 2020, a total of 193,318 cases of COVID-19 were reported in Dallas, with daily average case rates exceeding 50 per 100,000 for over 7 weeks. An adaptable survey functionality within a newly implemented COVID-19 surveillance system provided an opportunity to assess case knowledge and attitudes about isolation and contact tracing efforts.

Methods
COVID-19 illnesses were classified using the 2020 CSTE case definitions. Cases were interviewed and records reviewed for exposures and illness characteristics. Supplemental questionnaires assessing knowledge of public health recommendations were given to a convenience sample of 987 cases during the month of December 2020. Fishers exact and chi-square analyses were performed using SAS 9.4.

Results
Of the 987 respondents, 99% reported beginning isolation on or before receipt of test results, and 1% were not in isolation at the time of public health interview. Of cases reporting contacts, 92% had advised household members to quarantine prior to interview, and 91% did not want public health to call their household. Of cases reporting non-household close contacts, 75% had advised these contacts to quarantine prior to interview, and 91.3% did not want the health department to call these persons. Cases ≥ 65 years were less likely to have notified their own close contacts (OR: 0.2; 95% CI=0.1-0.8) of their test results, and more likely to prefer the health department to notify their household contacts of their positive result (OR: 4.1; 95% CI=1.3-12.5). Compared with White cases, Hispanic cases were less likely to be aware that their test was positive at the time of interview (OR: 0.3; 95% CI=0.1-0.7). Non-White cases were less likely to be aware of resources for food, rent and utility assistance prior to interview (OR: 0.25; 95% CI=0.1-0.7). All respondents perceived the public health interview to have been of some value to them, most often to answer their questions about retesting (51%) and duration of isolation (48%).

Conclusion
The aversion of a majority of COVID-19 cases for health department notification of their contacts is a significant deterrent to name-based contact tracing approaches. Acknowledgement of this limitation could better focus existing resources on the delivery of expedited notifications and information to contacts by proxy.

Disclosures
All Authors: No reported disclosures
140. Antibiotic Prophylaxis for Upper Gastrointestinal Bleed in Liver Cirrhosis: Less May Be More
Authors: Mansoor Armaghan-e-Rehman , Hadi Yousaf B , Naqvi Syeda Fatima Z , Khan Ali Y , Khan Raja S , Singal Ashwani , Kupec Justin 
Published: December 2021

Abstract

Background
Antibiotics in patients with cirrhosis and upper gastrointestinal bleeding are shown to improve outcomes. Little is known regarding optimum duration of prophylactic antibiotics, with 7 days of therapy generally recommended. Antibiotic duration has not been compared to outcomes in current scientific literature. The goal of our study was to study the effect of shorter antibiotic duration on outcomes.

Methods
This was a retrospective cohort study of patients with cirrhosis presenting with upper GI bleeding at our institute from 2010-2018. Patients were divided into three cohorts based on duration of antibiotic administration: 1-3 days, 4-6 days, and 7 days or more. Rates of infection within 30 days, time to infection, rebleeding and mortality were compared between the three groups. Multivariable analysis was conducted to evaluate independent risk factors for infection.

Results
Medical charts of 943 patients with cirrhosis and upper GI bleed were reviewed. 303 patients did not have concomitant confirmed or suspected infection on presentation, of these 243 patients received antibiotics for prophylaxis and were included for analysis. Seventy-seven patients received antibiotic therapy for 3 days or less, 69 patients for 4-6 days, and 97 patients &gt;6 days. The groups were well matched in demographic & clinical variables. 27 patients developed infections within 30 days of bleed. High MELD score at presentation and presence of ascites were associated with infection within 30 days. Rates of infection were not statistically different between the antibiotic groups (p= 0.78). In the 30 days following GI bleed, pneumonia was the most diagnosed infection (11 patients) followed by UTI (8 patients). Four patients developed spontaneous bacterial peritonitis and 3 were diagnosed with bacteremia. There was no difference in time to infection (p= 0.75), early re-bleeding (p=0.81), late re-bleeding (p= 0.37) and in-hospital mortality (p= 0.94) in the three groups. Six patients developed C. Difficile infection, none of whom were in the short antibiotic group.

Conclusion
Short course of antibiotics for prophylaxis (3 days) appears safe and adequate for prophylaxis in patients with cirrhosis and upper gastrointestinal bleeding if bleeding has abated and there is no active infection.

Disclosures
All Authors: No reported disclosures
1215. A Mixed Methods Study on Severe Bacterial Infections in People Who Inject Drugs
Authors: Hrycko Alexander , Eckhardt Benjamin , Mateu-Gelabert Pedro , Ciervo Courtney 
Published: December 2021

Abstract

Background
Severe bacterial infections (SBI) associated with intravenous drug use have been increasing in frequency in the U.S. over the last decade. This mixed methods study aims to identify the risk factors associated with SBI in hospitalized individuals with recent injection drug use.

Methods
We conducted 34 quantitative and 15 qualitative interviews between August 2020 and June 2021 at Bellevue Hospital in New York City. Eligible participants were (1) &gt;/= 18 year of age, (2) admitted with a SBI, and (3) reported injection drug use within the 90 days prior to admission. Quantitative and qualitative data was obtained using a quantitative survey and in-depth, semi structured interviews of participants respectively. Analysis was performed to examine trends and explore common themes potentially contributing factors to SBI.

Results
Of the 34 participants included, the median age was 37.5, 85% were male, 53% white, and 65% reported being homeless within the past 3 months. Endocarditis was the most common primary diagnosis (65%). Median length of hospital stay was 24 days and 35% required ICU level care during admission. A causative microorganism was identified in 85% of participants and 50% had Staphylococcus aureus as the sole organism. Discharges against medical advice occurred in 35%. Daily injection drug use in prior 30 days was 95% with a median of 10 injections per day. In the 30 days prior to admission, 50% reported an increase in injection frequency, 80% reported reusing needles and/or syringes, 75% reused cookers, 65% reused cottons. Analysis of qualitative interview data revealed high risk injection behaviors. Participants were not practicing and unaware of strategies to reduce their risk of drug injection-related SBI. Prior hospitalizations for SBI did not impact on this knowledge deficit on what constitutes bacterial infection risk and how to prevent it.

Conclusion
Study findings highlight the complexity of the injection drug use process and the potential social and physiological pathways leading to SBI. Multiple domains at the structural, network, and individual level that impact drug injection practices and provide context by which these factors predispose and lead to physiological tissue damage and the development of SBI among PWID.

Disclosures
Benjamin Eckhardt, MD, MS, Gilead Sciences (Grant/Research Support)
142. Impact of an Antimicrobial Stewardship Intervention on Antibiotic Prescribing in Patients with Obstetric Infection and Penicillin Allergy
Authors: Quartuccio Katelyn , Golden Kelly , Tesini Brenda L , Heintz Eric , Seligman Neil , Stern Jessica 
Published: December 2021

Abstract

Background
Antibiotics are commonly administered in the peripartum period and most patients with penicillin allergy can tolerate beta lactams, which are preferred for the prophylaxis and treatment of several common obstetric infections. The purpose of this study was to evaluate the impact of a stewardship intervention bundle (including updates to institutional antibiotic guidelines, reclassification of severe penicillin allergy, development of order sets, and a physician champion) on the management of obstetric infections in patients with reported penicillin allergy.

Methods
This was a multicenter, retrospective study of adult patients presenting for labor and delivery who received at least one dose of antibiotics for an infectious indication May 1, 2018 to October 31, 2018 (pre-intervention) and May 1 2020 to October 31, 2020 (post-intervention). The primary outcome was the composite rates of patients with a reported penicillin allergy who received a preferred agent for Group B Streptococcus (GBS) prophylaxis, intraamniotic infection, or cesarean surgical site infection (SSI) prophylaxis.

Results
A total of 192 patients with a documented penicillin allergy were evaluated (96 patients each in pre- and post-intervention groups). Hives were the most commonly reported allergy in both groups (40% vs 39%, P=0.883). Following stewardship interventions, there was a significant increase in the rate of preferred antibiotics prescribed to patients with penicillin allergy (34.3% vs 84.3%, P&lt; 0.001), driven mainly by patients with non-severe allergy (18.4% vs 82.9%, P&lt; 0.001). There were non-statistically significant trends toward lower rates of postpartum endometritis, 30-day readmission, 90-day SSI, and neonatal early onset sepsis. Allergic reactions in the post-intervention group were limited to itching and rash in one patient each; both resolved with medical management.

Conclusion
A comprehensive antibiotic stewardship intervention increased preferred antibiotic prescribing for treatment and prophylaxis of obstetric infections. Pregnant patients with non-severe penicillin allergies, even those reporting hives, can tolerate beta-lactam antibiotics. The potential positive impact on clinical outcomes warrants additional investigation.

Disclosures
Neil Seligman, MD, Natera (Consultant)UpToDate (Other Financial or Material Support, Author)
1235. Roles of Tetracyclines for Treatment of Stenotrophomonas maltophilia Pneumonia
Authors: Alhayani Taha , Philpott Carolyn , Liao Siyun , Gentene Anthony , Mueller Eric 
Published: December 2021

Abstract

Background
Stenotrophomonas maltophilia is a multidrug resistant organism with limited antibiotic treatment options. Sulfamethoxazole-trimethoprim (TMP-SMZ) is considered first line agent based on in vitro studies and clinical evidence. Minocycline has been showed to be active on in vitro studies and also has been explored in small retrospective studies However, doxycycline in the same class has variable in susceptibility in in vitro studies and has not been evaluated for efficacy in treatment of S. maltophilia infections The purpose of this research is to compare minocycline and doxycycline to TMP-SMZ for treatment of S. maltophilia pneumonia.

Methods
This retrospective, multi-center study evaluated hospitalized patients treated for S. maltophilia pneumonia with minocycline, doxycycline, or TMP-SMZ for clinical success, microbiologic success, and recurrence or reinfection within 30 days that required treatment. The inclusion criteria were patients ≥18 years old with S. maltophilia confirmed on respiratory culture from January 2013 to November 2020. Patients were classified as treatment with tetracyclines (minocycline or doxycycline) or TMP-SMZ based on definitive agent used for ≥50% of the treatment course and a minimum of four days. Patients with S. maltophilia resistant or intermediate to definitive therapy, and patients with combination therapy for treatment for S. maltophilia pneumonia were excluded.

Results
A total of 21 patients were included in tetracyclines group and 59 patients included in TMP-SMZ group. There was no difference in clinical success (28.6% vs. 25.4%; P = 0.994) or microbiologic success (n=28, 55.6% vs. 66.4%; P= 0.677) between tetracyclines and TMP-SMZ, respectively. Recurrence or reinfection requiring treatment (n=24) was higher in the tetracyclines group but not statistically significant compared to TMP-SMZ (66.7% vs. 26.7%; P= 0.092). A subgroup analysis showed no difference between doxycycline, minocycline, and TMP-SMZ for these three aims.

Conclusion
Clinical and microbiologic success were similar in patients treated with tetracyclines compared to TMP-SMZ for S. maltophilia pneumonia. This data suggests minocycline and doxycycline may be an option to treat S. maltophilia pneumonia, but conclusive clinical data continues to be lacking.

Disclosures
Anthony Gentene, PharmD, advisory board with Theravance Biopharma and Mylan (Consultant)
1245. In Vitro Activities of Ceftaroline and Comparator Agents Against Bacterial Pathogens Collected from Patients with Skin and Skin Structure Infections: ATLAS Global Surveillance Program 2012-2019
Authors: Hackel Meredith , Stone Gregory , Sahm Daniel F 
Published: December 2021

Abstract

Background
Ceftaroline fosamil, the prodrug of ceftaroline, is a parenteral cephem approved for the treatment of patients with skin and skin structure infections (SSSIs) caused by Staphylococcus aureus (both methicillin-susceptible [MSSA] and methicillin-resistant [MRSA] isolates), β-hemolytic streptococci (Streptococcus pyogenes, S. agalactiae, S. dysgalactiae), and select species of Enterobacterales (Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca). The current study is part of the ATLAS (Antimicrobial Testing Leadership and Surveillance) program and evaluated the current activities of ceftaroline and comparator agents against commonly encountered bacterial isolates associated with SSSIs.

Methods
From 2012 to 2019 the ATLAS program received 124,694 bacterial isolates that had been cultured by 493 clinical laboratories in 71 countries from samples of patients diagnosed with SSSIs. All isolates were transported to IHMA, (Schaumburg, IL, USA) where their identities were confirmed using MALDI-TOF mass spectrometry and antimicrobial susceptibility testing performed following standardized CLSI broth microdilution methodology (M07). Percent susceptibilities were determined using 2021 CLSI MIC breakpoints. Phenotypic extended-spectrum β-lactamase (ESBL) screening and confirmatory testing were performed using the CLSI M100 method.

Results
The in vitro activity of ceftaroline is summarized in the following table. Overall, &gt;99.9% of MSSA and 92.8% of MRSA from SSSI were susceptible to ceftaroline (MIC ≤1 µg/ml); 7.1% of MRSA isolates were ceftaroline-susceptible dose-dependent (MIC 2-4 µg/ml) with greatest proportion being from Chile (53.3% of 392 isolates), S. Korea (29.3% of 321 isolates), and China (24.7% of 652 isolates). Twelve ceftaroline-resistant MRSA were observed, consisting of 11 of 109 isolates from Thailand (10.1%) and 1 of 161 from China (0.6%). All S. pyogenes and 88.0% of ESBL-negative Enterobacterales were susceptible to ceftaroline.
Results Table

Conclusion
Ceftaroline continues to demonstrate potent in vitro activity against clinically relevant pathogens associated with SSSIs.

Disclosures
Meredith Hackel, PhD MPH, IHMA (Employee)Pfizer, Inc. (Independent Contractor) Gregory Stone, PhD, AztraZeneca (Shareholder, Former Employee)Pfizer, Inc. (Employee) Daniel F. Sahm, PhD, IHMA (Employee)Pfizer, Inc. (Independent Contractor)
1252. In Vitro Activity of Aztreonam-Avibactam and Comparator Agents Against Enterobacterales from Patients with Bloodstream Infections collected during the ATLAS Global Surveillance Program, 2015-2019
Authors: Lob Sibylle , Kazmierczak Krystyna , Arhin Francis , Sahm Daniel F 
Published: December 2021

Abstract

Background
Treatment options for β-lactamase-producing Enterobacterales are limited, particularly for infections caused by metallo-β-lactamase (MBL)-producing strains. The β-lactam/non-β-lactam β-lactamase inhibitor combination aztreonam-avibactam (ATM-AVI) is active in vitro against Enterobacterales isolates carrying MBLs, including those co-producing β-lactamases of Class A, C, and some class D enzymes. This study evaluated the in vitro activity of ATM-AVI and comparators against Enterobacterales isolates collected in 2015-2019 from patients with bloodstream infections (BSI) as part of the ATLAS program.

Methods
Non-duplicate clinical isolates were collected in 53 countries in Europe, Latin America, Asia/Pacific (excluding mainland China and India), and Middle East/Africa. Susceptibility testing was performed by CLSI broth microdilution and interpreted using CLSI 2021 and FDA (tigecycline) breakpoints. ATM-AVI was tested at a fixed concentration of 4 µg/mL AVI. MDR was defined as resistant (R) to ≥3 of 7 sentinel drugs: amikacin, aztreonam, cefepime, colistin, levofloxacin, meropenem, and piperacillin-tazobactam. PCR and sequencing were used to determine the β-lactamase genes present in all isolates with meropenem MIC &gt;1 µg/mL, and Escherichia coli, Klebsiella spp. and Proteus mirabilis phenotypically positive for ESBL activity (2015) or with aztreonam or ceftazidime MIC &gt;1 µg/mL (2016-2019).

Results
ATM-AVI was active in vitro against Enterobacterales isolates from BSI (MIC90, 0.12 µg/mL), with 99.97% of isolates inhibited by ≤8 µg/mL of ATM-AVI, including 100% of isolates that produced MBLs. ATM-AVI tested with MIC90 values of 0.5 µg/mL against subsets of cefepime-nonsusceptible (NS), meropenem-NS, amikacin-NS, colistin-resistant, and MBL-positive Enterobacterales (Table). The tested β-lactam comparators showed susceptibility of &lt; 79% against these subsets of resistant isolates.
Results Table

Conclusion
Based on MIC90 values, ATM-AVI was the most potent agent tested against drug-resistant and MBL-positive subsets of Enterobacterales collected from BSI. The promising in vitro activity of ATM-AVI warrants further development of this combination for treatment of BSI caused by drug-resistant Enterobacterales.

Disclosures
Sibylle Lob, PhD, IHMA (Employee)Pfizer, Inc. (Independent Contractor) Krystyna Kazmierczak, PhD, IHMA (Employee)Pfizer, Inc. (Independent Contractor) Francis Arhin, PhD, Pfizer, Inc. (Employee) Daniel F. Sahm, PhD, IHMA (Employee)Pfizer, Inc. (Independent Contractor)
1259. Carbapenems Versus Non-carbapenem Beta-Lactams for the Treatment of Ceftriaxone-Susceptible and Piperacillin-Tazobactam-Nonsusceptible Enterobacterales Isolates
Authors: Baalbaki Nadeem , Blum Sharon , Bosco Michael , Akerman Meredith , Zaki Lana , Johnson Diane 
Published: December 2021

Abstract

Background
Ceftriaxone-susceptible (CRO-S) and piperacillin-tazobactam-non susceptible (TZP-NS) Enterobacterales isolates have become a frequently isolated phenotype emerging in practice. The genotypic profile is still not clearly elucidated, although prior genotypic sequencing data of these isolates with this phenotypic profile suggests that they are not extended-spectrum beta-lactamase (ESBL) producers. Due to the unfamiliarity with this phenotype and the potential for overuse of broad-spectrum antibiotics, we investigated the clinical outcomes of CRO-S/TZP-NS isolates with carbapenem versus non-carbapenem beta-lactam (NCBL) therapy.

Methods
This was a retrospective chart review of patients with a diagnosed infection caused by a CRO-S/TZP-NS Enterobacterales isolate admitted to any of the three NYU hospitals: Long Island, Tisch, or Brooklyn campuses, treated with a beta-lactam (BL) antibiotic from October 2015 to October 2020. The primary outcome was treatment failure defined as an escalation of antibiotics due to clinical worsening, 30-day all-cause mortality, or relapse of infection with the same genus and species. Patients who received ≥ 72 consecutive hours of BL antibiotics were considered to be on definitive therapy.

Results
A total of 111 patients were included in this study, 9 in the carbapenem group and 102 in the NCBL group. There was no statistically significant difference in the clinical failure rate between the two groups (0% vs 10.8% respectively, P=0.56). A univariate analysis assessed
the association of clinical failure with TZP, CRO, cefpodoxime, cefepime, and 1st-3rd generation cephalosporins grouped. There were no statistically significant increases in 30-day treatment failure in any of the individual categories.

Conclusion
There were no statistically significant differences in 30-day failure with the use of carbapenem vs NCBL antibiotics. No individual BLs or classes were associated with an increased risk of clinical failure. This study suggests that there is a role for NCBL antibiotics for Enterobacterales isolates with this phenotypic presentation and supports prior data that they are less likely to be ESBL producers. Prospective studies are warranted to confirm these findings.

Disclosures
All Authors: No reported disclosures
147. Defining the Optimal Serial Testing Interval and Features for Identifying Patients with Early SARS-CoV-2 Infection
Authors: Kanjilal Sanjat 
Published: December 2021

Abstract

Background
Serial testing for SARS-CoV-2 is necessary to prevent spread from patients early in infection. Testing intervals are largely derived from viral kinetic studies performed early in the COVID-19 pandemic. Laboratory and epidemiologic data accrued over the past year present an opportunity to use empiric models to define optimal serial testing intervals and features predictive of early infection.

Methods
Retrospective analysis of 15,314 inpatients within the Mass General Brigham healthcare system who had two tests within a 36-hour period between May 1 2020 and May 29 2021. Early infection was defined as having a negative test followed by a positive test. Patients with prior positive tests were excluded. The primary outcome was the proportion of patients in early infection over the total number tested serially, stratified by 4-hour testing intervals from the timestamp of the first test. Multivariate modeling was used to identify features predictive of early infection. Covariates included demographics, body site, PCR assay, location, community incidence, percent positivity, and median / skew of Ct value distributions.

Results
Of 19,971 test pairs, 193 (0.97%) were characterized as a negative followed by a positive within 36 hours. Bivariate analysis showed a close association between negative to positive test pairs during the first surge in spring 2020 that was not present during the winter surge. Negative to positive test pairs were most common in the 12 to 16 hour time interval (51/193, 26%, Figure 1). After controlling for covariates, the Roche cobas assay was more likely to identify patients with a negative to positive test pair relative to the Cepheid Xpert, Hologic Panther Fusion and Roche Liat assays. A second specimen from the lower respiratory tract was more likely to lead to a positive relative to other body sites. Community incidence and Ct value distributions were not predictive and there were no differences between nasal and nasopharyngeal swabs. All 4-hour time intervals from 16 to 36 hours were significant for predicting a negative to positive test pair (Table 1).
Figure 1. Distribution of negative to positive test pairs by 4 hour time intervals

Table 1. Multivariate regression predicting a negative to positive test pair

Conclusion
The likelihood of detecting early infection is dependent on PCR platform and body site of sampling. A range of time intervals between 16 to 36 hours after the initial test were likely to identify positive cases.

Disclosures
Sanjat Kanjilal, MD, MPH, GlaskoSmithKline (Advisor or Review Panel member)