bluuebunny/crossref_metadata_2025_split huggingface dataset:
2800. Pragmatic Assessment of Influenza Vaccine Effectiveness in the DoD (PAIVED): Influenza-Like-Illness Rates in Year 1
Authors: Schofield Christina , Richard Stephanie , Colombo Rhonda , Collins Limone , Ganesan Anuradha , Geaney Casey , Lalani Tahaniyat , Markelz Ana E , Maves Ryan , Mende Katrin , Seshadri Srihari , Spooner Christina , Utz Gregory , Warkentien Tyler , Coles Christian L , Burgess Timothy 
Published: October 2019

Abstract

Background
Influenza-like illnesses (ILI) are common in military populations due to close living and working conditions, physical exertion, and exposure to novel viruses. The PAIVED trial aims to compare the effectiveness of 3 FDA approved influenza vaccines in active-duty military, retiree, and dependent populations, and will also provide information about the burden, impact, and severity of ILI.

Methods
Participants were enrolled in the 2018–2019 influenza season at 5 geographically diverse military facilities. Active duty, non-recruit military personnel, retirees, and dependents were randomized to receive influenza vaccine (egg-based, recombinant, or cell-culture derived) and then completed weekly electronic surveys throughout the influenza season. If a participant reported ILI symptoms during surveillance, 2 in-person visits with study personnel were scheduled for confirmed ILI. Nasal swabs and blood samples were collected for diagnostic and immunologic testing.

Results
Among the 852 non-recruit participants enrolled in PAIVED, 25% were active military, 36% retired military, and 39% dependents. Almost half (48%) were female, and 72% were white, 15% African American, 6% Asian, 4% multiple races, and 3% unknown or other race. 788 participants (92%) responded to at least one surveillance questionnaire. Participants reported 407 ILIs (Figure 1), of which 160 met the study case definition. Between 12 and 28% of the participants experienced an ILI during the surveillance period, and 12 people experienced 2 ILIs. Most sites reported a median 2–3 days of fever/feverishness or chills and 3–4 days of reduced activity associated with an ILI episode. No viruses were detected in 58% of nasal swabs, 1 virus in 40%, and 2 viruses in 1% of swabs (Figure 2 for pathogen data).

Conclusion
During the period under study, ILIs were common with 1 in 6 participants experiencing a confirmed ILI, many of which were 6–8 days in duration. ILIs resulted in reduced activity, although few individuals reported missing work or school, a situation that could result in greater likelihood of transmission to others. Planned analyses will provide additional information about the pathogens responsible for these illnesses and help guide effective prevention policies in these populations.

Disclosures
All authors: No reported disclosures.
173. Successful Treatment of Carbapenem-Resistant Klebsiella pneumoniae (CR-Kp) Aortic Valve Endocarditis with Ceftazidime–Avibactam
Authors: Alegro Jason V , Argentine Sarah , Russell Lisa 
Published: October 2019

Abstract

Background
The emergence of carbapenem-resistant Klebsiella pneumoniae (CR-Kp) presents significant clinical challenges with our limited antibiotic armamentarium. Infective endocarditis caused by CR-Kp is rare, with few cases reported in the literature. The use of the novel β-lactam/β-lactamase inhibitor combination ceftazidime–avibactam (CAZ-AVI) in this setting has only been described in one 2018 case in Italy. Guidance in how these novel antibiotics should be used becomes more prudent as the prevalence of complicated CR-Kp infections increases.

Methods
A 51-year-old male with a past medical history of a gunshot wound to the neck, type 2 diabetes, and osteomyelitis status post right below-the-knee and left toe amputations presented to the emergency department with altered mental status and right upper extremity weakness. The patient’s hospital course was complicated by hemorrhagic stroke, left above-the-knee amputation, and intraoperative cardiac arrest. Subsequently, blood cultures on hospital days 41 and 43 grew CR-Kp and a transthoracic echocardiogram (TTE) showed moderate to severe aortic regurgitation.

Results
Antimicrobial therapy was changed from imipenem-cilastatin and colistin to CAZ-AVI and amikacin. The organism was found to be susceptible to CAZ-AVI and amikacin, intermediate to colistin, and resistant to all carbapenems. A transesophageal echocardiogram (TEE) confirmed the presence of a small mobile vegetation on the aortic valve with perforation and severe regurgitation. CAZ-AVI and amikacin were continued for two weeks, and then switched to CAZ-AVI and ertapenem for an additional four weeks. Follow-up blood cultures on and after day 44 were negative for CR-Kp. A TTE performed after therapy completion no longer demonstrated aortic regurgitation; however, the valves were poorly visualized. The patient then suffered anoxic brain injury after a second cardiac arrest, thought to be unrelated to endocarditis. The patient’s family then decided on hospice care and the patient expired.

Conclusion
We report the successful treatment of CR-Kp endocarditis with CAZ-AVI and amikacin for two weeks followed by CAZ-AVI and ertapenem for four weeks. This regimen can be a viable option for patients that present with this rare multidrug-resistant infection.

Disclosures
All authors: No reported disclosures.
2804. Systematic Review of the Role of Prenatal Ultrasound and Amniocentesis in the Diagnosis and Evaluation of Congenital Zika Syndrome
Authors: Viens Laura , Fleck-Derderian Shannon , Baez-Santiago Madelyn , Oduyebo Titilope , Broussard Cheryl , Khan Sumaiya , Meaney-Delman Dana 
Published: October 2019

Abstract

Background
To inform recommendations for optimal screening for fetal outcomes of Zika virus infection during pregnancy, we examined the relationship between prenatal diagnostics (ultrasound examination and amniotic fluid Zika virus testing) and postnatal congenital Zika syndrome (CZS) abnormalities.

Methods
Systematic searches were performed in 27 medical and public health databases from inception to March 21, 2018 for articles with the keywords “Zika,” “prenatal,” “ultrasound,” and “amniocentesis.” A total of 2,281 unique records were identified. Two reviewers independently assessed titles, abstracts, and full texts for content and relevance. Together, the 61 included articles describe 307 mother–fetus/infant dyads; 291 were included in the systematic review of prenatal ultrasound and Zika virus, and 38 were included in the systematic review of amniocentesis and Zika virus.

Results
There were 155 fetuses with CZS findings on prenatal ultrasound examination (53.3%); among them, postnatal CZS abnormalities were reported for 114 (73.5%). High proportions of microcephaly (72.4%), cerebral atrophy (85.7%), and ventriculomegaly (80.6%) were confirmed at pregnancy completion. In addition, 20.6% of the 136 fetuses without any CZS findings on prenatal ultrasound had CZS abnormalities identified at pregnancy completion. Structural CZS abnormalities were identified in approximately equal proportions after pregnancy completion in dyads with and without Zika virus RNA detected in one or more amniotic fluid specimen (53.8% and 58.3%). In 6 pregnancies, Zika virus RNA was detected in amniotic fluid, but no Zika virus RNA was detected in a subsequent amniocentesis specimen.

Conclusion
Prenatal ultrasound can detect structural findings associated with Zika; prenatal detection may vary with factors such as timing of infection, timing of ultrasound, technical expertise, and severity of abnormalities. Detection of Zika virus RNA in amniotic fluid did not predict the risk for CZS abnormalities in this review, and clearance of Zika virus RNA from amniotic fluid appears possible after maternal infection. The decision to perform diagnostic testing for Zika remains a shared decision between patients and clinicians, and more data are needed to define clinical predictors that will inform these decisions.

Disclosures
All authors: No reported disclosures.
300. Drug Use Characteristics and Hepatitis C Antibody Prevalence in Southern Illinois
Authors: Defever Kali , Patrick Sarah L , Layden Jennifer E , Fletcher Scott , Van Ham Brent , Jenkins Wiley D , Pho Mai T 
Published: October 2019

Abstract

Background
Hepatitis C virus (HCV) infection rates have increased among younger, rural persons nationally. We report on a preliminary sample of a study examining HCV acquisition risk factors among rural persons who inject drugs (PWID) or person who use opioids (PWUO) non-medically.

Methods
We used respondent-driven sampling (RDS) to recruit PWID/PWUO in southern, rural Illinois as part of a larger study on infectious disease rates among social networks of PWID and illicit opioid users. Participants were surveyed regarding drug and sexual risk behavior, healthcare access, stigma, and social networks, and underwent rapid screening for HCV (OraQuickÒ HCV Rapid Antibody Test) and other infections. Using R software, we generated descriptive statistics to characterize HCV prevalence.

Results
Between July 2018 and April 2019,135 current PWID/PWUO were recruited, screened, and surveyed (58.5% male; 82.2% white; mean age 40.1 years). HCV rapid tests detected antibodies (HCV+) among 53 of 112 screened (47.3%). HCV+ participants were more likely to be white (96.2% vs. 83.1%, P = 0.006) than HCV antibody negative (HCV-) participants and showed a bimodal age distribution with peaks in the 25–30 and 45–50 age ranges. Reported injection drug use and heroin use in the past 30 days was significantly more common among HCV+ participants (96.2% vs. 72.9%, P = 0.001, and 12.9 vs. 7.9 days, P = 0.024) While HCV+ participants less frequently used methamphetamine compared with HCV -participants, the use of that drug was still high in both groups (11.9 vs. 18.4 days of use in the past 30 days, P = 0.01). HCV+ participants reported fewer social network members than HCV- participants (2.2 vs. 3.0, P = 0.048).

Conclusion
In this analysis of a preliminary sample, HCV exposure was high; with those positive for HCV antibody showing a bimodal age distribution, high frequency of multiple drug use, and smaller social network size compared with HCV negative counterparts. Upon RDS-based enrollment completion and pending analysis we will further examine HIV RNA status as well as the specific associations between network size and other risk factors that may inform disease screening and treatment interventions.

Disclosures
All authors: No reported disclosures.
301. Risk of Virologic Failure with Antiretroviral Switches in HIV/HCV Co-infections
Authors: Mosquera Diana M , Wilder Julius , Ellis Alicia , Naggie Susanna 
Published: October 2019

Abstract

Background
Direct-acting antivirals (DAA) and antiretroviral (ARV) medications pose treatment challenges in HIV/HCV co-infection. Management of contraindicated combinations varies across practices. ARV switches may increase the risk of HIV virologic and treatment failure, and has been reported to increase the risk of DAA treatment failure. This analysis assesses how switches in ARV regimen impacts treatment outcomes in HIV/HCV co-infection.

Methods
This retrospective cohort study includes patients 18 years and older with stable HIV/HCV co-infection (HIV RNA<50 for ≥6 months) who received DAA HCV therapy. Data were obtained using the Centers for AIDS Research Network of Integrated Clinical Systems. The “ARV switch” cohort is defined as patients undergoing a switch in ARV regimen within 6 months prior to DAA treatment. The “no ARV switch” cohort was defined as patients without a change in ARV during the same time period. The primary outcome is HIV treatment failure which is a composite endpoint including HIV virologic failure (defined as confirmed loss of HIV viral suppression), discontinuation/change of ARV regimen, progression to AIDS, or death. We compared baseline characteristics, the proportion of patients free of HIV treatment failure, free of HIV virologic failure, and that achieved sustained viral response (SVR) at 12 and 24 weeks after DAA treatment among ARV switch and no ARV switch groups.

Results
Of the 256 patients, 63/256 (25%) underwent an ARV switch (Table 1). At baseline, the most common regimen in the ARV switch group was protease inhibitor (PI)-based while for the no ARV switch group, it was an integrase strand transfer inhibitor (INSTI)-based regimen. HIV/HCV transmission risk factors, HCV genotype, and AST/ALT were similar among the two groups (Table 1). The proportion with HIV treatment and virologic failure, and the proportion achieving SVR12/24 were similar among the ARV switch and no ARV switch groups.

Conclusion
HIV treatment and virologic failure, and SVR12/24 were not different among patients who did or did not undergo a switch in their ARV regimen prior to DAA treatment. This suggests that switches in the ARV regimen for DAA treatment of HCV do not negatively impact HIV or HCV outcomes among patients with HIV/HCV Coinfection.

Disclosures
All authors: No reported disclosures.
180. Klebsiella pneumoniae and K. oxytoca Bacteremia: Differences in Host, Source, and Antibiotic Susceptibility
Authors: Youssef Dima , Hooshmand Babak , Riederer Kathleen M , Johnson Leonard B , Khatib Riad 
Published: October 2019

Abstract

Background
Klebsiella species (KS) bloodstream infection (BSI) is often caused by K. pneumoniae (KP). K. oxytoca (KO) is emerging and implicated in antibiotic-associated right-sided colitis. We compared the clinical and microbiological characteristics of KP and KO.

Methods
We reviewed blood culture (BC) results (January 1, 2010–December 31, 2017), selected patients with KS in ≥1 BC, reviewed their medical records, abstracted patient demographics, source of bacteremia, antibiotics susceptibility, and outcome. Each patient was counted once. We compared KP and KO cases. All differences were assessed by the chi-square test and regression analysis, using SPSS.

Results
We encountered KS in 975/14,256 (6.8%) positive BC, representing 611 BSI including 537 KP-BSI (484 patients) and 55 KO-BSI cases (54 patients); each patient was counted once. Mean age and prevalence of diabetes and most comorbidities were similar but KO was less frequent in African Americans (40.7% vs. KP [61.3%]; P = 0.005) and in patients with neurological debility (Stroke, paraplegia, multiple sclerosis; 11.1% vs. KP [24.8%]; P = 0.03). KO BSI was more frequent in IVC BSI and was absent in pneumonia-associated BSI (table). Antibiotic resistance was rare among KO isolates except for cefazolin-intermediate susceptibility (42.6% vs. 1.7%; P < 0.001). CREs were limited to KP. Logistic regression analysis confirmed KO link to IVC (OR = 3.57; 95% CI: 1.89, 6.76; P < 0.001) and Caucasian race (OR = 2.46; CI: 1.37, 4.42; P = 0.003). Mortality rate was comparable (28.1% [KP] vs. 35.2% [KO]; P = 0.3).
Source and antibiotic susceptibility (%) in K. pneumoniae and K. oxytoca bacteremia

Conclusion
KO and KP BSI differ in the type of host and source, suggesting different colonization dynamics. KO remains antibiotic-susceptible but might be cefazolin less susceptible. Prospective studies are needed to confirm differential cephalosporin susceptibility and delineate host–pathogen interactions.

Disclosures
All authors: No reported disclosures.
182. Appropriateness of Treatment Duration for S. aureus Bacteremia (SAB)
Authors: Griebe Kristin , Kenney Rachel , Davis Susan L 
Published: October 2019

Abstract

Background
An algorithm-based guide to optimal treatment duration in staphylococcus bacteremia demonstrated a non-inferior rate of clinical success compared with standard of care. The purpose of this descriptive study was to assess appropriateness of staphylococcus bacteremia duration of therapy according to the SAB treatment algorithm.

Methods
IRB approved, retrospective cohort describing antibiotic use in S. aureus bacteremia across a health system from January to March 2019. Patients were included if they had at least one blood culture with S. aureus. Exclusion criteria included transfer from outside hospital, concurrent osteomyelitis diagnosis, and death within 72 hours of positive culture. The primary outcome was the appropriate duration of antibiotics for uncomplicated SAB. Secondary outcomes included clinical failure, antibiotic adverse effects, 90-day mortality, and hospital length of stay.

Results
A total of 59 patients were included. The median age was 66 years old and 22 patients (37.3%) were female. Diagnosis: uncomplicated SAB 28 (47.5%) and complicated SAB 31 (52.5%); MRSA 32 (%) and MSSA 27 (%). Infectious Diseases Consultation 56 (94.9%). 4 patients died before treatment duration was determined. Breakdown of treatment durations and clinical failures are listed in Tables 1. Appropriate duration occurred in 9 (32.1%) of patients with SAB. Overall, 14 patients experiences antibiotic adverse effects, 11 which occurred in antibiotic use for ≥4 weeks, 4 occurred in patients with uncomplicated SAB treated for ≥4 weeks. Breakdown of adverse effects: acute kidney injury 9, myositis 1, rash 1, nausea/vomiting 1, anaphylaxis 1, hypersensitivity pneumonitis 1.

Conclusion
Excess treatment duration for uncomplicated SAB was common (16%), in this study, inconsistent with best practice recommendations. 79% of adverse effects occurred in patients who received a ≥4 week course. The results of this study suggest more efforts are needed to implement contemporary evidence-based treatment duration algorithms for uncomplicated SAB to minimize unnecessary antibiotic harm.

Disclosures
All authors: No reported disclosures.
197. Infective Endocarditis Over a Five-Year Period in an Academic Teaching Center: The Validity of ICD Codes vs. Manual Chart Review
Authors: Haden Michael , Mahdee Sobhanie Mohammad , Hebert Courtney , Castillejo Becerra Clara , Turner Abigail N 
Published: October 2019

Abstract

Background
Opioid dependence and overdose are at epidemic levels in the United States. Ohio has the third highest rate of opioid-related overdose deaths. Infectious complications of intravenous drug use (IDU) include increased acquisition of hepatitis C, HIV and infective endocarditis. In this study, we aimed to characterize cases of infective endocarditis admitted to our healthcare system over a five-year period. We additionally sought to determine the validity of using ICD codes to identify infective endocarditis cases and IDU.

Methods
Patients with ICD-9 or 10 discharge diagnosis codes for infective endocarditis were identified from our institution’s electronic health record. ICD codes pertaining to substance abuse were used to classify patients according to IDU status. Readmissions during the same episode of infective endocarditis were excluded. We compared chart review to ICD code for the identification of infective endocarditis and IDU in a random sample of 296 of 1590 cases.

Results
Of 296 charts reviewed, 133 (44.9%) were excluded because they did not meet criteria for definite infective endocarditis by modified Duke’s criteria or because the episode was a readmission. A total of 163 (55.1%) cases met inclusion criteria, all of whom were seen in consultation by the inpatient Infectious Disease service. Of these, 52 (31.9%) had ICD 9 or 10 codes linked to substance abuse. Following manual chart review, we established that in fact 86 of these 163 cases (52.8%) had evidence of substance abuse.

Conclusion
Misclassification due to use of ICD codes is a well-established challenge to epidemiological research. However, the extent of misclassification in this analysis was greater than expected. If prior research on IDU and infective endocarditis has relied on medical record data alone without verification through manual chart review, the observed epidemiological trends may not be accurate.

Disclosures
All authors: No reported disclosures.
216. Association Between Days to Initiate Appropriate Therapy and Hospital Length of Stay Among Adult Hospitalized Patients With Gram-negative Bloodstream Infections (GN-BSI)
Authors: Lodise Thomas , Kanakamedala Hemanth , Hsu Wei-Chun , Cai Bin 
Published: October 2019

Abstract

Background
The deleterious outcomes associated with delay receipt of appropriate therapy are well documented. However, scant data exists on the consequences of each day delay of appropriate therapy and subsequent outcomes among adult hospitalized patients with GN-BSIs.

Methods
Study design: a retrospective cohort analysis. Study population: consecutive adult, hospitalized patients with a GN-BSI (11 most prevalent pathogens) in 1 of 181 institutions contributing microbiology data to the Premier Healthcare Database (October 2010–Sep 2015). Exclusion criteria: age < 18 years; diagnosis of pregnancy or cystic fibrosis, died or discharged within 2 days of index GN-BSI culture, lack of sufficient antibiotic susceptibility or treatment data to determine appropriateness. Day of initiating appropriate therapy was defined as the first day when the patient received an antibiotic with in vitro activity against the GN-BSI post index culture. Results were summarized by Kaplan–Meier estimates, and Cox Proportional-Hazards (CPH) analyses modeling discharge to home were conducted. Time to initiate appropriate therapy (0, 1–2 days, 3–4 days, ≥5 days) was included in the CPH model as an ordinal variable.

Results
A total of 40,549 patients met selection criteria. Mean (SD) age was 67.5 (16.1) years and 54% were female. E. coli and K. pneumoniae were the most common GN-BSI (58.0% and 18.3%, respectively). Approximately 30% of patients were in the ICU at index GN-BSI and in-hospital mortality was 6.8%. The mean (SD) time to receive appropriate therapy post index GN-BSI culture was 0.6 (2.7) days, and 69.7%, 22.5%, 5.7% and 2.1% received appropriate therapy in 0, 1–2, 3–4, and ≥5 days of index GN-BSI, respectively. The mean/median LOS post index GN-BSI by 0, 1–2, 3–4, and ≥5 days delays in appropriate treatment were 8.3/6, 9.8/7, 11.5/8, and 19.2/11 days respectively. Kaplan–Meier plots are shown in Figure 1. In the CPH model, each interval delay in appropriate therapy was associated with a 21% decrease in the likelihood of being discharged home for patients with GB-BSIs.

Conclusion
Hospital length of stay was found to increase when appropriate therapy was delayed. These findings highlight the critical need for early appropriate therapy among patients with GN-BSIs.

Disclosures
All authors: No reported disclosures.