bluuebunny/crossref_metadata_2025_split huggingface dataset:
2057. Outpatient Antibiotic Stewardship “Bundles up” in Winter with Peer Comparison, URI Order Set and Education: Is It Enough to Weather the Storm?
Authors: Akay Okan I , Dave Rohini , Khosla Amit , Kraska CherylAnn , Hopkins Brian J , Bork Jacqueline 
Published: October 2019

Abstract

Background
Inappropriate antibiotic use is a growing problem in the outpatient setting. Approximately 90% of all antibiotics are prescribed in outpatient practices. Nonetheless, 30–70% of antibiotic prescriptions (ARx) are unnecessary. Outpatient antimicrobial stewardship (AS) is much needed and the best approach is unknown. We used a bundle approach to outpatient AS during the winter months, by implementing a peer comparison (PC) report, upper respiratory infection (URI) order set and broad education.

Methods
This is a quasi-experimental project during the period October 2018 to March 2019 (FY19) to evaluate the impact of a bundled intervention in primary care clinics at the VA Maryland Health Care System. A historical control group from the same period the previous year (FY18) was used for comparison. The intervention included an AS directed didactic and URI order set followed by an email in 1/2019 with: (1) censored PC report (ARx/1,000 encounters) with outliers defined as above 1.5 × interquartile range, (2) URI order set reminder, and (3) education. The primary outcome was total ARx per 1,000 encounters in primary care clinics. A random sampling of 200 charts was done to compare proportion of antibiotic appropriateness and number of emergency department (ED) visits and adverse drug events (ADEs) in FY19 Q1 and FY19 Q2. Poisson regression was carried out, in addition to Χ2-statistic.

Results
There were 3,799 vs. 3,429 ARx in FY18 and FY19, respectively, with a rate difference of 3.3 ARx per 1,000 encounters (P = 0.0056). Q1 to Q2 ARx rate increased by 7.8 and 8.0 ARx per 1,000 encounters in FY18 and FY19, respectively. Forty-eight percent (28/58) of the providers confirmed receipt of email. There were 3 and 4 outliers in FY19 Q1 and Q2, respectively. Appropriate ARx for FY19 Q1 and Q2 was found to be 45% and 35% (P = 0.44), respectively. The most common indications were URI (18% vs. 18%), urinary tract infection (13% vs. 21%). ED visits (10% vs. 6%) were uncommon and there were no ADEs.

Conclusion
E-mail communication with bundled approach had no effect on ARx or antibiotic appropriateness; however general AS presence and URI order set tempered some use. Removing peer censoring, providing face-to-face education and intensifying antibiotic order sets are additional interventions to be implemented.

Disclosures
All authors: No reported disclosures.
2099. Use of Infectious Diseases Source-Specific Electronic Sepsis Order Sets is associated with Improved Survival in Sepsis: An Evaluation of 46 Hospitals in a Large Health Care System
Authors: Daragjati Florian , Sebastian Danielle , Roberts Phillip , Rashid Asifur , Erlinger Thomas , Fakih Mohamad G 
Published: October 2019

Abstract

Background
Compliance with evidence-based treatment bundles in patients with sepsis can lead to improved survival in persons with sepsis or septic shock. A way to ensure the adoption of best practices is the early use standardized order sets based on suspected source of infection.

Methods
The patient population was built by connecting electronic health record (EHR) to administrative data. In the EHR, we identified patients who had a sepsis discharge diagnosis code based on the International Statistical Classification of Disease and Related Health Problems (ICD−10), from August 1, 2018 to February 28, 2019. We evaluated the empiric use of sepsis order sets and patient outcomes. We adjusted for age, gender, Elixhauser Comorbidity Score (ECS), intensive care unit (ICU) status, and admission type. For the analysis, we included patients age 18 and older from facilities where we were able to match greater than 70 percent of patients. Matching was done by facility on medical record number and discharge date.

Results
There were 26,604 patients included in the analysis. The overall mortality rate was 10.67% (n = 2,839). Mortality associated with sepsis in patients that had a sepsis order set used was 8.92% (791/8,872), while for those whom a sepsis order set was not used was 11.55% (2,048/17,732). When mortality data were adjusted for age, gender, ECS, ICU status, admission type and hospital size, the use of sepsis order sets was associated with an adjusted odds ratio of 0.793 (95% CI 0.722, 0.868). In addition, in all sepsis patients who had an ICU admission, the use of the sepsis order sets was associated with an adjusted odds ratio of 0.804 (95% CI 0.725, 0.890). Similarly, in all sepsis patients who did not have an ICU admission, the use of the sepsis order sets was associated with an adjusted odds ratio of 0.688 (95% CI 0.556, 0.847).

Conclusion
The use of the standardized sepsis order sets in patients with sepsis was associated with a 20.7% relative risk reduction in mortality. In conjunction with rapid recognition of sepsis, early initiation of the sepsis order sets may lead to improved mortality in patients with sepsis.

Disclosures
All authors: No reported disclosures.
2134. Differential Changes in Breath Volatile Metabolites to Identify Carbapenem-Resistant Enterobacteriaceae (CRE) in a Murine Pneumonia Model
Authors: Ismail Nour , Albashash Hazem , Thalavitiya Acharige Mahesh J , Hejazi Mohamad , Leon Astudillo Carmen , Aloum Obadah , Koshy Seena , Fredenburgh Laura , Balasubramanian Raji , Skurnik David , Guillard Thomas , Koo Sophia 
Published: October 2019

Abstract

Background
CRE infections cause significant mortality, in large part because rapid identification of these infections is challenging. We tested the hypothesis that CRE and their isogenic carbapenem-susceptible counterparts have differential metabolic responses to carbapenem therapy.

Methods
We generated isogenic pairs of E. coli, E. cloacae, and K. pneumoniae by inserting a blaNDM-1-containing plasmid into carbapenem-susceptible E. coli, E. cloacae, and K. pneumoniae. We confirmed phenotypic meropenem (MPM) resistance per CLSI breakpoints for Enterobacteriaceae (MIC ≥4) in the NDM-1+ member and susceptibility (MIC≤1) in the NDM-1- member of each pair. We administered 2 × 108 CFU of each isolate intranasally to 23–28 g male C57BL/6J mice, infecting 6 mice with the NDM-1+ member and 6 with the NDM-1− member of each species pair (12 mice per bacterial species). 24 hours after infection, we treated 3 mice in each NDM-1+ and NDM-1− bacterial species cohort with MPM over 4 hours, and the other 3 mice in each cohort with saline over 4 hours as controls, confirming adequate infection (a target of 106 CFU/g of lung tissue) in quantitative lung homogenate cultures. We then collected breath samples from each mouse via tracheostomy using a murine ventilator, identifying all volatile metabolites in each sample using thermal desorption-gas chromatography/tandem mass spectrometry. We used Wilcoxon tests to examine differences in metabolite abundance between MPM and saline-treated control mice in the NDM-1+ and NDM-1− a member of each species pair, with a two-sided P-value threshold of < 0.1.

Results
Several breath volatile metabolites changed differentially within each NDM-1+/NDM-1- pair, outlined in Table 1 (E. coli), Table 2 (E. cloacae), and Table 3 (K. pneumoniae). Each listed metabolite that changed with MPM did not change with MPM in mice infected with each isogenic counterpart

Conclusion
There are differential in vivo metabolic responses with effective vs. ineffective treatment of mice with pneumonia caused by E. coli, E. cloacae, and K. pneumoniae pairs that are genetically identical other than blaNDM-1; this differential treatment response can potentially be used to identify these infections.

Disclosures
All authors: No reported disclosures.
2140. Utility of Respiratory Specimen Gram Stain for Predicting Final Culture Result in Patients with Clinically Diagnosed Pneumonia
Authors: Seadler Jessica , Smith Terri , Faust Andrew C 
Published: October 2019

Abstract

Background
Obtaining a high-quality respiratory tract specimen for Gram stain and culture in patients with suspected lower respiratory tract infections is recommended by the IDSA guidelines. However, conflicting results correlating Gram stain with final culture growth has led to questions about the utility of a respiratory specimen Gram stain. The purpose of this study was to assess the correlation of Gram stain with final culture in patients with pneumonia.

Methods
A retrospective chart review was conducted to evaluate adult inpatients with a diagnosis of pneumonia (based on the CDC surveillance definition) who had a respiratory specimen submitted for Gram stain and culture. A specimen was considered acceptable if less than ten epithelial cells were visualized under low power field. Each Gram stain was compared with the corresponding final culture. The primary outcome was to evaluate the correlation of Gram stain with final culture using positive predictive value (PPV), negative predictive value (NPV), sensitivity, and specificity. A culture was considered negative if no bacteria were isolated or if only normal flora grew. Secondary outcomes were PPV and NPV based on antibiotic exposure prior to specimen collection, semi-quantitative number of bacteria on Gram stain, and collection method. Additionally, discordance between Gram stain and final culture morphology was evaluated.

Results
A total of 269 acceptable specimens were assessed. Of the 72 specimens with a positive Gram stain, 41 yielded bacteria in final culture (PPV: 56.9%). In contrast, 154 of the 197 specimens with a negative Gram stain were associated with negative final culture (NPV: 76.7%). The NPV of Gram stain was decreased when antibiotics were given for > 24 hours pre-specimen. The PPV of Gram stain improved as an increasing amount of bacteria were reported. Less invasive collection methods had a lower PPV but a higher NPV in comparison to invasive collection methods. Finally, the discordance rate between Gram stain and final culture morphology was low.

Conclusion
This study shows inconsistent results regarding the ability of Gram stain to predict final culture. Pneumonia should continue to be managed clinically and caution taken prior to adjusting empiric antimicrobial regimens based solely on the Gram stain.

Disclosures
All authors: No reported disclosures.
2142. Comparison of Molecular-Based vs. Conventional Culture-Based Screening Methods for Detection of Carriers of Extended-Spectrum β-Lactamases (ESBL) and Carbapenemases-Producing Enterobacteriacae (CPE)
Authors: Martischang Romain , Renzi Gesuele , François Patrice , Bonetti Eve-Julie , Cherkaoui Abdessalam , Pugin Jérôme , Schrenzel Jacques , Harbarth Stephan 
Published: October 2019

Abstract

Background
Active surveillance and contact precautions may prevent cross-transmission of ESBL-producing Enterobacteriaceae and CPE. Culture-based methods delaying results might increase risk of cross-transmission, and lead to unnecessary preemptive contact precautions. This observational cohort study compared rapid Loop-Mediated Isothermal Amplification (LAMP) assays to conventional culture-based methods for ESBL and CPE screening of critically ill patients.

Methods
This study was conducted in the adult ICUs at Geneva University Hospitals. We collected consecutive rectal ESwabs routinely performed, either for admission screening of high-risk patients or once weekly routine screening of all patients hospitalized in the ICU. Eazyplex® SuperBug CRE system (Amplex Biosystems) assays were performed directly on rectal Eswabs according to the manufacturer’s instructions. For the conventional culture-based method, we used chromID® ESBL agar (ESBL) coupled with chromID®OXA-48. Discordant specimens were retested using disk diffusion tests and the same LAMP assay on isolates. Microbiological turn-around times (TAT; from the reception in the laboratory to result notification) were collected.

Results
Overall, 290 rectal ESwabs were analyzed. ESBL and CPE prevalence were 16.7% and 1.0%, respectively. Three discordant isolates could not be further investigated and considered as LAMP false positive. Adjusted analytical performances were for CPE: 100% (95IC 100–100%) sensitivity, 99.6% (99.0–100%) specificity, 75% (32.6–100%) PPV, and 100% (100–100%) NPV, and for ESBL: 85% (73.9–96.1%) sensitivity, 98.8% (97.4–100%) specificity, 91.9% (83.1–100%) PPV, and 97.6% (95.7–99.5%) NPV. A decrease in TAT was observed when comparing LAMP screening assay against conventional method (50.3 hours vs. 6.2 hours; Figure 1). Figure 2 shows time reductions comparing both screening strategies.

Conclusion
Screening strategies based on LAMP could fasten discontinuation of unnecessary pre-emptive isolation time for patients at risk and earlier implementation of contact precautions for previously unknown carriers of ESBL or CPE.

Disclosures
All authors: No reported disclosures.
2154. Rapid Microorganism Identification From Blood and Enrichment Fluid Cultures Using MALDI-TOF Mass Spectrometry Following Abbreviated Incubation on Chocolate Agar Plates
Authors: Chew Rusheng , Otome Ohide , Harris Owen , Walton Aaron , Hewson Darrren , Luppino Michael , Cowan Raquel 
Published: October 2019

Abstract

Background
The more rapidly a pathogen can be identified in cases of sepsis, the more swiftly targeted therapy can be commenced. We aimed to evaluate the accuracy and clinical utility of a method for rapid microorganism identification from blood and sterile site fluid enrichment cultures using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) in a high-throughput regional microbiology laboratory.

Methods
A drop of blood or fluid from cultures flagging positive was inoculated onto chocolate agar and incubated until MALDI-TOF MS analysis 5–6 hours later. Results obtained with conventional overnight incubation were used as controls. The number of isolates reliably and correctly identified, and recommendations for changes to clinical management were recorded. A pilot study was undertaken to demonstrate feasibility using a cut-off score of ≥2.0, following which the method was integrated into the laboratory workflow using a cut-off score of ≥1.7 (identification to genus level) because patient management can often be altered with this degree of accuracy.

Results
In the pilot study, 154/210 blood cultures (73.3%) were reliably identified (score ≥2.0) and, of these, 151 (98.1%) were correctly identified. The operational study included 144 blood cultures and 14 sterile site fluid enrichment cultures. 121 (76.6%) were reliably identified (score ≥1.7) and, of these, 117 (96.7%) were correctly identified. Four isolates (2.5%) were yeasts, 104 (65.8%) were Gram-positive bacteria and 50 (31.6%) were Gram-negative bacteria. 78 of the 104 bacteria (75.0%) were correctly identified. The median score for Gram-positives was 1.89 (IQR 0.36). For Gram-negatives, 47 of the 50 isolates (94.0%) were correctly identified. The median score for Gram-negatives was 2.29 (IQR 0.14). No yeasts were reliably identified. Recommendations for changes to clinical management were made for seven (3.8%) and nine patients (6.0%) in the pilot study and operational study, respectively. The method was easily integrated into the laboratory workflow and did not require additional staff.

Conclusion
We build on previous work by providing a simple method for rapid micro-organism identification which allows easy integration into a busy laboratory, and which improves clinical management.

Disclosures
All authors: No reported disclosures.
2158. Cost-Effectiveness and Budget Impact of a Point-of-Care Nucleic Acid Amplification Test for Diagnosis of Group A Streptococcal Pharyngitis in the United States
Authors: Karichu James , Cheng Mindy , Sickler Joanna , Munakata Julie , Bilir S Pinar , Kruger Eliza 
Published: October 2019

Abstract

Background
Group A streptococcal (GAS) pharyngitis is common in the United States (US). Each year, approximately 12 million people seek medical care for pharyngitis, accounting for ~2% of ambulatory care visits. The gold standard method for diagnosing GAS is culture. However, because culture is time intensive, rapid antigen detection tests (RADTs), with or without culture confirmation, are commonly used. Although RADTs provide results quickly, test sensitivity has been shown to be sub-optimal, which can lead to inappropriate treatment decisions. Recently, highly sensitive point-of-care nucleic acid amplification tests (POC NAAT), such as the cobas® Liat® System, have emerged. The objective of this study was to evaluate the cost-effectiveness (CE) and budget impact (BI) of adopting POC NAAT compared with RADT+culture confirmation to diagnose GAS pharyngitis from the US third-party payer perspective.

Methods
A decision-tree economic model was developed in Microsoft Excel to quantify costs and clinical outcomes associated with POC NAAT and RADT+culture over a one-year period. All model inputs were derived from published literature and public databases. Model outputs included costs and clinical effects measured as quality-adjusted life days (QALDs) lost. One-way and probabilistic sensitivity analyses were performed to assess the impact of uncertainty on results.

Results
CE analysis showed that POC NAAT would cost $44 per patient compared with $78 with RADT+ culture. POC NAAT was associated with fewer QALDs lost relative to RADT+ culture. Therefore, POC NAAT may be considered the “dominant” strategy (i.e., lower costs and higher effectiveness). Findings were robust in sensitivity analyses. BI analysis showed that adopting POC NAAT for diagnosis of GAS could yield cost-savings of 0.3% vs. current budget over 3 years. This is due to savings associated with testing, GAS-related complications, antibiotic treatment and treatment-associated complication costs.

Conclusion
Results suggest that adopting POC NAAT to diagnose GAS would be considered cost-effective and yield cost-savings for US payers relative to RADT+culture. Access to POC NAAT would be important to optimize appropriate GAS diagnosis and treatment decisions.

Disclosures
All authors: No reported disclosures.
110. Clinical Outcomes of Patients with Secondary Bacteremia in the Omadacycline Phase 3 Acute Bacterial Skin and Skin Structure Infections and Community-Acquired Bacterial Pneumonia Studies
Authors: Sakoulas George , Eckburg Paul B , Manley Amy , Tzanis Evan , Garrity-Ryan Lynne , Das Anita F , Curran Marla , Noble Bob , McGovern Paul C 
Published: October 2019

Abstract

Background
Low serum concentrations of tetracycline antibiotics may raise concerns on their efficacy in patients with secondary bacteremia, especially in comorbid patients and in those with higher acuity of illness. Omadacycline (OMC), an aminomethylcycline antibiotic, showed noninferiority to linezolid (LZD) in two acute bacterial skin and skin structure infections (ABSSSI) studies (Omadacycline in Acute Skin and skin structure Infections Study [OASIS]-1 and -2), or to moxifloxacin (MOX) in a community-acquired bacterial pneumonia (CABP) study (Omadacycline for Pneumonia Treatment In the Community study [OPTIC]). This analysis considers clinical outcomes in patients with secondary bacteremia identified in these studies.

Methods
Baseline blood cultures were taken from adult patients enrolled in Phase 3 randomized, double-blind clinical studies of OMC. Patients received ≥1 treatment dose: N = 1,347 ABSSSI (OMC n = 676; LZD n = 671); N = 774 CABP (OMC n = 386; MOX n = 388). Efficacy was evaluated by investigator assessment of clinical response at a post-treatment evaluation (PTE) 7–14 days (ABSSSI) or 5–10 days (CABP) after the last dose.

Results
Bacteremia was confirmed in 63 patients (3%) across the three studies. Staphylococcus aureus was the most common pathogen in patients with ABSSSI (N = 30: OMC n/N = 7/13; LZD n/N = 9/17), with a median treatment duration of median 9 days (OMC) and median 10 days (LZD). Streptococcus pneumoniae was the most common pathogen in patients with CABP (N = 33; OMC n/N = 11/15; MOX n/N = 11/18), with a median treatment duration of 11 days (OMC) and 14 days (MOX). Clinical success was numerically comparable between treatment groups within each study (figure) after completion of therapy.

Conclusion
The clinical successes of patients receiving OMC for ABSSSI or CABP with secondary bacteremia were comparable to results for LZD and MOX, respectively. Although limited by the small sample size, data from ABSSSI and CABP study patients with secondary bacteremia provide reassurance for the use of OMC. Real-world OMC data in patients with ABSSSI and CABP will be needed to assess outcomes in patients with additional comorbidities and/or higher acuity of illness.

Disclosures
All authors: No reported disclosures.
2216. Pneumonia in the ICU: Epidemiology and Outcomes
Authors: Blaha Michael , Zelus Casey , Cawcutt Kelly , Cawcutt Kelly , Marcelin Jasmine R , Marcelin Jasmine R , Kalil Andre C , Samson Kaeli 
Published: October 2019

Abstract

Background
The understanding of pneumonia epidemiology has been evolving in recent years with an increased awareness of viral respiratory pathogens since the introduction of respiratory pathogen panels. However, epidemiological and clinical data on pneumonia due to co-infection are lacking.

Methods
A single-center retrospective analysis of mechanically ventilated adult patients treated in critical care units from January to October 2018 was performed on patients with one or more pathogen identified via microbiological testing of a bronchoalveolar lavage (BAL) sample. SOFA and APACHE II scores at the time of admission to the critical care unit and SOFA the day the of BAL were obtained, along with ICU length of stay, duration of ventilation, and pathogens. Associations between categorical variables and co-infection status were assessed using Chi-Square tests, Fisher exact tests, and t-tests. Differences in counts of days between coinfection status groups were analyzed by generalized linear models.

Results
140 bronchoalveolar lavage samples met inclusion criteria, of which 31 were determined to have co-infection with two or more pathogens identified. Of the two methods used to obtain BAL samples, co-infection was found in a higher proportion of patients undergoing bronchoscopic BAL as compared with blinded (35.6% vs. 7.5%; P < 0.0001). Patients with co-infection were determined to be statistically more likely to require a longer duration of mechanical ventilation (P = 0.03); however, there was no difference overall seen in 30 day mortality rate (23.4% vs. 19.57%; P = 0.61).

Conclusion
Co-infection is a significant risk factor for a prolonged duration of mechanical ventilation compared with patients with single pathogen pneumonia. In addition, the use of bronchoscopic BAL appears to be a significant factor in identifying higher rates of co-infection compared with blinded. Although our study failed to demonstrate a significant difference in mortality rates, this could have occurred due to the small sample size.

Disclosures
All authors: No reported disclosures.