bluuebunny/crossref_metadata_2025_split huggingface dataset:
1769. The Impact of Checkpoint Inhibitor Immunotherapy on Infections in Lung Cancer Patients
Authors: Malek Alexandre , Fares Johny , Khalil Melissa , Hachem Ray Y , Chaftari Anne-Marie , Jiang Ying , Kontoyiannis Dimitrios P , Fossella Frank , Chaftari Patrick , Mulanovich Victor E , Viola George , Raad Issam I 
Published: October 2019

Abstract

Background
Immune checkpoint inhibitors (ICI) therapy has ushered cancer treatment into a potentially curative era. However, infectious complications remain largely unknown and the few studies that described infectious complications associated with ICI had no comparative control groups. We assessed the rate of infections in patients with non-small cell lung cancer (NSCLC) treated with ICI plus conventional chemotherapy (CC) vs. CC alone.

Methods
We performed a comparative single-center retrospective cohort study of patients with NSCLC who received de novo treatment with either Pembrolizumab or Nivolumab, and/or Ipilimumab combined with CC including Pemetrexed and Carboplatin vs. patients treated with CC alone between August 2016 and January 2019. We excluded all patients who were switched from CC to ICI or vice-versa. We evaluated patients’ characteristics, treatment modality, immune-related adverse events (irAEs), and outcome. Infections were defined by clinical signs and symptoms, microbiologic documentation, and/or imaging studies.

Results
A group of 126 patients who received ICI concurrently with CC were compared with 126 patients who received CC alone (control group). Patients in the ICI group were more likely to have stage IV NSCLC compared with the control group (P < 0.0001). Pembrolizumab was most commonly used as a single ICI agent in 107 patients (85%), followed by Ipilimumab and Nivolumab as dual therapy (9%). Confirmed infections were identified in 20 (16%) patients in the ICI group and 18 (14%) in the control group (P = 0.7). The control group had a higher rate of multiple infections at different times compared with the ICI group (P = 0.014). However, there was no significant difference in the types of infections (bacterial, fungal or viral) that occurred between the two groups. The irAEs were reported in 14 (11%) patients, 13 of them received corticosteroids with a median duration of 32 days (range, 15–64 days). Out of these patients, three (21%) developed confirmed infections of which two were viral upper respiratory tract infections and one was a bacterial urinary tract infection.

Conclusion
Patients with NSCLC treated with the combination of Immune Checkpoint Inhibitors plus Conventional Chemotherapy have comparable risk of developing infections compared with those on Conventional Chemotherapy alone.

Disclosures
All authors: No reported disclosures.
1779. Comparison of Two Zika IgM Antibody Capture Enzyme-linked Immunosorbent Assays (MAC-ELISA) in Symptomatic Patients from Dominican Republic, 2016
Authors: Kiechle Frederick , Carlton Ronald , Freddo Angelica , Quezada Henry 
Published: October 2019

Abstract

Background
Zika virus (ZIKV) is a Flavivirus transmitted to humans by Aedes mosquitos. To assess the clinical presentation in 434 symptomatic patients (64 men, 370 women [65 pregnant; 305 nonpregnant]) during a ZIKV outbreak in the Dominican Republic (DR) in 2016, we evaluated clinical symptoms, ZIKV by qualitative detection of ZIKV RNA and ZIKV IgM by two MAC-ELISA assays, one from CDC and performed by the Florida Department of Health, Jacksonville, FL and one from InBios International Inc., Seattle, WA (Zika Virus Detect).

Methods
The Aptima ZIKV assay (Hologic, San Diego, CA) was used to detect ZIKV by transcription-mediated amplification RT–PCR in serum, plasma, or urine. Corresponding clinical symptomology reports were reviewed for all 434 patients. The results from the two MAC-ELISA assays were evaluated by linear regression analysis. The two MAC-ELISA assays were reported as optical density (OD) ratios from a sample with three different antigens (P/N ratio for CDC Zika MAC-ELISA and Zika Immune Status Ratio or ISR for InBios Zika Virus Detect MAC-ELISA).

Results
There was a biphasic increase in ZIKV detection in April and late May/June 2016 in the 434 symptomatic patients. All 434 had one or more of four symptoms including rash, fever, conjunctivitis, and arthralgia. Linear regression analysis (log scale) of results from subject samples tested on the two MAC-ELISAs (282 total) revealed a slope of 1.172, y-intercept of 0.1584 and R2 of 0.587. In 88 RT–PCR-negative patients, 48 (54.5%) were positive by both MAC-ELISAs; 27 (30.7%) were negative by both MAC-ELISAs and 13 (14.7%) had discrepant results with a sensitivity of 85% for the InBios MAC-ELISA. The InBios also detected IgM in 54.4% of samples that were positive for ZIKV by RT–PCR attributable to errors in determining the days post symptom onset.

Conclusion
In 2016 there was a biphasic spike of ZIKV-positive infections in 434 symptomatic men and women tested in DR. Both linear regression analysis and our comparative analysis in the ZIKV RT–PCR-positive and negative cohorts demonstrate that the InBios Zika Virus Detect MAC-ELISA provides diagnostic results comparable to the CDC Zika MAC-ELISA.

Disclosures
All authors: No reported disclosures.
1978. Statements about Antibiotic Side-Effects and Patient Desire for Unnecessary Antibiotics
Authors: Miller Benjamin , Carson Kathryn , Pathak Sujay , Keller Sara C 
Published: October 2019

Abstract

Background
Antibiotic resistance is a global health emergency fueled in part by non-indicated use of antibiotics. Current public education campaigns primarily focus on the risks of global antibiotic resistance or society-wide adverse impacts of antibiotic misuse. There has been little research into what messages have the greatest impact on patient requests for non-indicated antibiotics.

Methods
We administered a survey at a primary care clinic in August 2018. Participants rated 18 statements about potential harm from antibiotics on how that statement changed their likelihood to request antibiotics for an upper respiratory tract infection (URI) on an 11-point Likert scale. These included 8 statements about potential harm to the individual, 4 statements about potential harm to contacts of the individual, and 6 statements about resistance or the societal impact of antibiotic misuse. Before and after the survey, participants rated how likely they were to request antibiotics for a URI.

Results
Of 1150 adult patients in clinic over the 6 days of the survey, 250 completed the survey. Statements about potential harm to the individual decreased patient likelihood to request antibiotics more than statements about societal impacts of antibiotic misuse. (P < 0.001). Statements about potential harm to contacts of the patient also decreased patient likelihood to request antibiotics more than statements about resistance or societal impacts of antibiotic misuse (P < 0.001). Statements discussing antibiotic resistance were less likely to impact patient likelihood to request antibiotics than statements not mentioning antibiotic resistance (P < 0.001). All statements decreased patient likelihood to request antibiotics. Overall likelihood to request antibiotics decreased after the survey (from 5.3 pre- to 3.1 post-survey, P < 0.001).

Conclusion
Statements about how potential harm of antibiotics to the individual had a greater impact than statements about resistance or societal impact of antibiotics. Our results suggest that when dissuading patients from requesting non-indicated antibiotics, providers and public health campaigns focus on the potential harm of antibiotics to the individual patient rather than on antibiotic resistance or societal impacts.

Disclosures
All authors: No reported disclosures.
1986. Impact of Two-Step Testing on the Diagnosis and Management of Clostridium difficile in a Multi-Hospital Healthcare System
Authors: Davis Angelina , Parker Todd , Coluccio Julia , Mann Kimberly , Dodds Ashley Elizabeth , Yarrington Michael E , Moehring Rebekah W , Sexton Daniel J , Couk Jesse , Zurawski Christine 
Published: October 2019

Abstract

Background
Distinguishing active C. difficile infection (CDI) from asymptomatic colonization remains a significant challenge. A multi-step testing algorithm can improve the diagnostic accuracy of CDI and associated antibacterial prescribing. This study evaluated the impact of two-step testing on CDI rates and management in a multi-hospital community health system.

Methods
Two-step C. difficile testing (PCR for initial screening followed by EIA for toxin detection) was implemented in 6 acute care community hospitals in April 2018. EIA testing was automatically performed on all stool samples with a positive C. difficile PCR result. Prior to implementation, PCR alone was used to identify CDI. Messaging attached to the PCR laboratory report alerted prescribers of discrepant results (PCR +/EIA -). Anti-C. difficile therapy was at the discretion of the prescriber. We performed a retrospective cohort analysis over a 2-year period to evaluate the effect of two-step testing on system-wide hospital-onset CDI (HO-CDI) per 10,000 patient-days (PD) and anti-CDI antimicrobial use (AU) in days of therapy (DOT) per 1,000 PD. Segmented negative binomial regression with hospital clustering was used to estimate predicted HO-CDI rate for the baseline period between April 1, 2017 through March 31, 2018 and the post-intervention between May 1, 2018 through March 31, 2019. The implementation date at all sites in April 2018 was unknown; therefore, this month was removed from the analysis. Anti-CDI agents included fidaxomicin, metronidazole, and oral vancomycin, but may have included non-CDI indications for metronidazole.

Results
A total of 115 HO-CDI cases were identified; 91 (79%) before and 24 (21%) after. Prior to implementation of two-step testing, CDI rates declined at 4% per month (P = NS). The rate immediately dropped by 36% (P = 0.004) after two-step testing was implemented, but the trend did not significantly change (P = 0.52, Figure 1). Community-onset CDI rates also decreased during this time period. Combined facility-wide anti-CDI agent use was 824.87 before and 838.21 DOT/1,000 PD after and did not significantly change.

Conclusion
Use of a two-step approach for CDI testing reduced HO-CDI rates, but did not have a significant impact on anti-CDI antibiotic use in a multi-hospital community health system.

Disclosures
All authors: No reported disclosures.
1992. Initial Procalcitonin Level and Antibiotic Practice Patterns Among Patients with Acute Respiratory Infections
Authors: Costales Jessica K , Nomura Jim H , Joanie. Chung Wen-Ling , Ironside Kristen , Sim John J , Salama Paul 
Published: October 2019

Abstract

Background
The utility of procalcitonin (PCT)-guided algorithms to decrease antibiotic use has been extensively studied in clinical trials. The guidance that PCT provides as it translates into real-world practice is unclear. This study aims to describe real-world antibiotic prescribing practices in relation to PCT in patients admitted to our US-based health system with acute respiratory infections.

Methods
Retrospective cohort study of 1,606 adults admitted within our US health system from January 1, 2016 to December 31, 2018 with a primary diagnosis of acute upper or lower respiratory infection with at least one PCT measurement. Antibiotic practice patterns were evaluated using pharmacy analytic information and antibiotic status to note antibiotics given prior to and 36 hours after PCT result. Analysis of discordance with initial PCT level was defined as continuing or starting antibiotics after a low PCT level (PCT ≤0.25 μg/L) and withholding or discontinuing antibiotics after a high PCT level (PCT > 0.25 μg/L).

Results
Antibiotic prescription patterns after the result of initial PCT level are summarized in Table 1. Only 242 patients (15%) had more than one PCT-level checked. Overall, antibiotic discordance with initial PCT result was 45%; mostly attributed to continuing or starting antibiotics despite a low PCT level (77%). (Figure 1) There were 496 patients who were initially started and continued on antibiotics despite a low PCT result. Of this subgroup, only one patient had a serial PCT measured, and 12 were admitted for Chronic Obstructive Pulmonary Disease (COPD) exacerbation and continued on azithromycin/doxycycline after result of the low PCT.

Conclusion
Utilization of antibiotics went against well-studied PCT cutoffs 45% of the time, primarily driven by antibiotic use at low PCT levels. Only a small number were continued on azithromycin/doxycycline for anti-inflammatory effect in COPD exacerbations, indicating that most patients received antibiotics for presumed bacterial infection despite the high negative predictive value of PCT. This study illustrates PCT use in real-world practice did not significantly alter prescribing practices, potentially from lack of confidence or knowledge in interpreting PCT results and lack of serial measurements to aid in decision-making.

Disclosures
All authors: No reported disclosures.
2007. Impact of Combining Rapid Diagnostics with an Interpretation Guide on Vancomycin Usage for Contaminant Blood Cultures Growing Coagulase-Negative Staphylococci (CoNS)
Authors: Wu Simon , Watson Richard L , Graber Christopher J 
Published: October 2019

Abstract

Background
Contaminant blood cultures can lead to unnecessary antibiotic use, longer admissions and increased costs. Rapid diagnostics, like the BioFire® FilmArray® Blood Culture Identification (BCID) Panel, can potentially lessen these harms. BioFire BCID was implemented at VA Greater Los Angeles in 7/2017. When providers review BCID results, they are also directed to an interpretation guide developed by our antimicrobial stewardship program. This study aimed to determine the impact of BioFire BCID with this interpretation guide on unnecessary vancomycin use for contaminant blood cultures growing CoNS.

Methods
This was a retrospective cohort study on adult inpatients with contaminant blood cultures positive for CoNS. We evaluated cases before BCID (April 2016–July 2017) and after BCID (July 7/2017–December 2018) implementation. Cases with patients who died or were discharged prior to preliminary results, polymicrobial cultures, no empiric vancomycin use, or where vancomycin was indicated were excluded. We defined a “case” as anytime a provider concurrently ordered blood cultures and empiric antibiotics. Our primary outcome was the duration of unnecessary vancomycin. Secondary outcomes were time to discontinuation/modification of any empiric antibiotic, length of stay (LOS), LOS in ICU and 30-day mortality.

Results
A total of 99 cases were included (N = 45 pre-BCID; N = 54 post-BCID). Demographics between the 2 groups were largely similar except the post-BCID group had more patients with end-stage renal disease (ESRD) (14 vs. 4, P = 0.037) and more frequent infectious disease (ID) consultation (21 vs. 8, P = 0.027). The post-BCID group had shorter mean duration of unnecessary vancomycin (53.0 hours vs. 38.1 hours, P = 0.0029). After controlling for ESRD and ID involvement, the mean duration of unnecessary vancomycin was not significantly different between the 2 groups (P = 0.30 and P = 0.49, respectively). There was no difference in time to modification/discontinuation of any empiric antibiotic (44.6 hr vs. 35.0 hr, P = 0.36). There was no difference in mean LOS, mean LOS in ICU, or 30-day mortality.

Conclusion
Shorter duration of unnecessary vancomycin for CoNS bacteremia after BCID implementation and provision of an interpretation guide may have been driven in part by more frequent ID consultation.

Disclosures
All authors: No reported disclosures.
2012. Trends in Microbiological Culture Collection Across Veterans Affairs Medical Centers and Community Living Centers, 2010 to 2017
Authors: Appaneal Haley , Caffrey Aisling , Hughes Stephanie , Lopes Vrishali , Jump Robin L , LaPlante Kerry , Dosa David 
Published: October 2019

Abstract

Background
Microbiological cultures are critical in the diagnosis of infection, identification of pathogenic organisms, and tailoring antibiotic use. However, unnecessary collection of cultures, particularly from the urine, may lead to overuse of antibiotics. There have been no national studies to evaluate trends in the collection of cultures in acute and long-term care settings. Here we describe changes in the collection of cultures nationally across Veterans Affairs medical centers (VAMCs) and Community Living Centers (CLCs).

Methods
All positive and negative cultures collected from 2010 to 2017 among Veterans admitted to VAMCs or CLCs were included. Cultures were categorized by specimen source (urine, blood, skin and soft tissue, or lung). Joinpoint software was used for regression analyses of trends over time and to estimate annual average percent changes with 95% confidence intervals (CI).

Results
A total of 5,089,640 cultures from 158 VAMCS and 342,850 cultures from 146 CLCs were identified. The number of cultures collected for all culture types in VAMCs and CLCs decreased significantly. The number of cultures collected per admission decreased significantly by 5.5% annually among VAMCs (95% CI −7.0 to −4.0%) and by 8.4% annually among CLCs (95% CI −10.1 to −6.6%). The proportion of positive cultures decreased 1.6% annually among VAMCs (95% CI −2.3 to −0.9%) and remained stable among CLCs (-0.4% annually, 95% CI, −1.1 to 0.4%). The most common culture source among VAMCs was blood (36.2%), followed by urine (31.8%), and among CLCs was urine (56.9%), followed by blood (16.0%). Urine cultures decreased by 4.5% annually among VAMCs (95% CI −5.4 to −3.6%) and 7.0% annually among CLCs (95% CI −7.6 to −6.4%).

Conclusion
Our study demonstrates a significant reduction in the number of cultures collected over time. Positive cultures decreased significantly in VAMCs, possibly indicating fewer culture-positive infections.In both VAMCs and CLCs, decreases in cultures taken may represent an important reduction in the collection of unnecessary cultures nationally driven by increased awareness about over-testing and over-treatment of presumed infection, particularly urinary tract infections.

Disclosures
All authors: No reported disclosures.
2013. Blood Culture Contamination in the Emergency Department: A Risk Factor Analysis
Authors: Klucher Justin , Lakkad Mrinmayee , Painter Jacob , Dare Ryan K 
Published: October 2019

Abstract

Background
Blood cultures (BCx) guide treatment for hospitalized patients, yet contaminated BCx lead to clinical uncertainty, impacting care. The Clinical and Laboratory Standards Institute (CLSI) recommends contamination rates should be <3%, yet our Emergency Department (ED) rate is consistently above this benchmark. Reasons for this are unclear, thus it is imperative to investigate potential risk factors for BCx contamination.

Methods
We performed a retrospective case–control risk factor analysis of patients with BCx collected in our ED between 2014 and 2018. Contaminated BCx were identified by the microbiology laboratory per American Society of Microbiology recommendations. Demographics, comorbidities, and clinical characteristics were evaluated in patients with false-positive/contaminated BCx (cases) and patients with negative BCx (controls). Potential risk factors identified in univariate analysis were included in a logistic regression model. Unadjusted and adjusted analyses were performed using SAS 9.4.

Results
25,668 BCx from 13,782 patients were included in analysis. 20,907 BCx from 11,266 (82%) patients were negative, 2,856 BCx from 1,504 (11%) patients were true positives, and 1,905 BCx from 1,012 (7%) patients were contaminated. Yearly ED contamination rates ranged from 5.0–9.3%. Collector contamination rates varied, though 38 (19%), 75 (35%), and 7 (3%) of 209 collectors had a contamination rate <3%, ≥ 10%, and ≥ 20%, respectively. Significant patient-specific risk factors identified in univariate analysis are listed in the attached table along with adjusted analysis.

Conclusion
In our analysis, we identified that older age, African American race, higher BMI, COPD, paralysis, and presenting in septic shock independently increases risk of having a contaminated BCx. Difficulty obtaining venipuncture in patients with these risk factors, often requiring multiple collection attempts, likely leads to decreased sterile technique. It is imperative to have a process assuring sterile technique in these high-risk individuals to minimize consequences associated with having a false-positive BCx result in these high-risk patients. Additionally, variable collector contamination rates seen in this study highlight the necessity for frequent technique in-service training.

Disclosures
All authors: No reported disclosures.
2017. Age-specific Distribution of Antimicrobial Days of Therapy (DOT) Using National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB Japan): Comparison with Defined Daily Doses per 1,000 Inhabitants Per Day (DID)
Authors: Yamasaki Daisuke , Tanabe Masaki , Muraki Yuichi , Kusama Yoshiki , Ishikane Masahiro , Tanaka Chika , Ohmagari Norio 
Published: October 2019

Abstract

Background
Nationwide surveillance of antimicrobial use (AMU) is often assessed by defined daily doses per 1,000 inhabitants per day (DID) as a measurement unit. We previously reported the age-specific distribution of AMU using National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB Japan), which archives e-claim big data (Infection. 2018 46:207–214). The estimated AMU assessed by DID could be underestimated in patients with diminished renal function and in pediatric patients. Our objective was to analyze days of therapy (DOT) using NDB and to evaluate its utility by comparing with DID.

Methods
The DID value was calculated by the same method in our previous study.The DOT values was extracted from data in NDB and were standardized by a population and were described as per 1,000 inhabitant days (DOTID). The values of DID, DOTID and the ratios (DID/ DOTID), the indicator for reflecting the extent of daily dosage were compared between three groups stratified by age groups (younger than 15 years: children, 15–64 years old: productive age, and older than 64 years: elderly).

Results
The total DID (oral, parenteral) from 2013 to 2016 in three age groups was shown in the following table. The total DID (oral, parenteral) in three age groups in 2016 were 16.31, 0.27 in the children, 12.82, 0.39 in productive age, and 15.91, 2.13 in elderly, respectively. Similarly, the total DOTID (oral, parenteral) in three age groups in 2016 were 36.15, 1.20 in the children, 16.48, 0.80 in productive age, and 23.52, 3.62 in elderly, respectively. The total DID/DOTID (oral, parenteral) in three age groups in 2016 were 0.45, 0.23 in the children, 0.78, 0.49 in productive age, and 0.68, 0.59 in elderly, respectively. The gap between DID and DOTID in children was much larger than that of other age groups regardless of dosage form, suggesting that AMU assessed by DID could be underestimated, especially in children.The gap between DID and DOTID in elderly was comparable with that in productive age, suggesting that daily dosage in the elderly is similar to that in productive age.

Conclusion
These results demonstrated the utility of AMU surveillance using the DOTID as a tool and benchmark to assess the AMU, especially in children, and the ratio of DID to DOTID could be useful as an indicator for reflecting the extent of daily dosage.

Disclosures
All authors: No reported disclosures.