bluuebunny/crossref_metadata_2025_split huggingface dataset:
1476. Impact of an Educational Campaign on Rates of Sputum Culture Acquisition as an Opportunity for Antibiotic De-escalation
Authors: Snawerdt Jessica , Bremmer Derek N , Carr Dustin R , Walsh Thomas L , Trienski Tamara , Buchanan Carley 
Published: January 2021

Abstract

Background
The 2019 community-acquired pneumonia (CAP) guidelines recommend obtaining a sputum culture in patients who are empirically treated for methicillin-resistant Staphylococcus aureus (MRSA) or Pseudomonas aeruginosa to assist clinicians in optimizing antimicrobial therapy. A previous study at our institution found respiratory cultures were rarely obtained in patients with CAP. As a result of these findings, an educational campaign was implemented to promote the use of an induced sputum protocol.

Methods
This was a multicenter, retrospective cohort study that included patients who were ≥18 years of age, had a diagnosis of CAP, and received ≥48 hours of anti-pseudomonal antibiotics. Patients were excluded if mechanically ventilated within 48 hours of admission or diagnosed with hospital-acquired or ventilator-associated pneumonia. Patients were grouped into pre- and post-intervention time periods. The intervention involved education on obtaining respiratory cultures including technique on induced sputums and updates to CAP order sets. The primary outcome was the rate of sputum culture acquisition. Secondary outcomes included duration of anti-pseudomonal and anti-MRSA therapy, in-hospital mortality, and length of stay.

Results
A total of 143 patients met inclusion criteria, 72 in the pre-implementation group and 71 in the post-implementation group. Baseline characteristics were similar between the two groups. More patients in the post-implementation group had a sputum culture obtained but the difference was not statistically significant (38.9% vs 53.5%; p=0.08). Anti-pseudomonal therapy was continued for an average of 5.6 days pre-implementation and 5.2 days post-implementation (p=0.499). There was also not a significant difference in anti-MRSA duration between the two groups (3.4 days vs 3.2 days; p=0.606). In-hospital mortality and length of stay were similar between the two groups.

Conclusion
An educational campaign focusing on the acquisition of induced sputums led to an increase in rates of sputum cultures collected. However, this did not correlate with a decrease in duration of anti-MRSA or anti-pseudomonal therapy. Further interventions should be made to optimize de-escalation of broad spectrum antibiotics based on sputum culture results.

Disclosures
All Authors: No reported disclosures
1477. Impact Of Resistance Thresholds On Mortality In Hospital-Acquired And Ventilator-Associated Pneumonia
Authors: Mazi Patrick B , Guillamet M Cristina Vazquez , Micek Scott , Kollef Marin 
Published: January 2021

Abstract

Background
Hospital-acquired (HAP) and ventilator-associated pneumonia (VAP) represent a significant source of morbidity and mortality in hospitalized patients. Numerous studies demonstrate mortality benefit with appropriate empiric therapy. Choosing the right empiric coverage is paramount; however, this decision becomes more challenging as rates of antibiotic resistance rise. Most recent HAP/VAP guidelines use an arbitrary population resistance rate of 20% to recommended methicillin-resistant Staphylococcus aureus (MRSA) coverage and double-coverage of resistant gram negative bacilli (GNB). Using this threshold has led to overuse of broad spectrum antimicrobials. The goal of this study is to mathematically explore the impact of this threshold on patient outcomes and link population resistance rates to individual mortality risk.

Methods
We used the concept of excess morality risk (EMR) to develop a theoretical simulation model based for HAP/VAP caused by GNB and MRSA empirically treated with piperacillin-tazobactam and vancomycin. EMR is the product of the proportion of HAP/VAP caused by GNB/MRSA, the rate of antibiotic (piperacillin-tazobactam/ methicillin) resistance in GNB and Staphylococcus aureus isolates and the difference in mortality between discordant and appropriate antibiotic therapy. Model parameters were obtained from large surveillance networks and published clinical trials.

Results
At the HAP/VAP guideline threshold of 20% methicillin resistance in SA isolates, the EMR was 0.3%; when the model included only culture positive patients, EMR was 0.6%. At a threshold of 20% resistance to piperacillin-tazobactam in GNB isolates, EMR was 1.9% and 3.1% when culture-negative patients were excluded. EMR increased as baseline risk of failure with discordant therapy increased (e.g. critically ill patients, ventilated HAP).
Risk Difference of Death for Staphylococcus aureus Isolates

Risk Difference of Death for Gram Negative Bacilli

Conclusion
This model offers a mathematical exploration of the individual excess risk for death in patients with HAP/VAP caused by GNB/MRSA because of discordant therapy. The objectivity of the model would better allow clinicians, guideline authors, and health policy makers to weigh excess risk versus possible harms of broad-spectrum therapy when developing population resistance thresholds cutoffs for empiric therapy recommendations.

Disclosures
All Authors: No reported disclosures
121. Temporal Trends in Urine Culture Rates in the U.S. Acute Care Hospitals During 2012–2017
Authors: Kazakova Sophia , McCarthy Natalie , Baggs James , Hatfield Kelly M , Wolford Hannah , Olubajo Babatunde , Jernigan John A , Reddy Sujan 
Published: January 2021

Abstract

Background
Decreasing inappropriate urine cultures in hospitalized patients has been a target of diagnostic stewardship to improve infection surveillance and antimicrobial use. The impact of such efforts has been largely unstudied. This study assessed temporal trends in urine culture rates in a cohort of acute care hospitals (ACHs) between 2012 and 2017.
Hospital Level Variation in Admission Urine Culture Rates

Hospital Level Variation in Post-admission Urine Culture Rates

Methods
We used microbiology data from ACHs participating in the Premier Healthcare Database and Cerner Health Facts to measure monthly urine culture rates. All cultures from the urinary tract collected on or before day 3 were defined as admission cultures (AC) and those collected on day 4 or later as post-admission cultures (PAC). Temporal trends in AC and PAC rates were estimated using general estimating equation models adjusting for hospital-level clustering, hospital size, teaching status, urban/rural designation, discharge month, and region.

Results
During the study period, ACHs had 20.8 million discharges and performed 4,946,717 urine cultures, of which 21% were PAC. In 2012 and 2017, the unadjusted AC rates were 18.7 and 18.4 per 100 discharges; the unadjusted PAC rates were 11.5 and 8.5 per 1,000 patient days (PD) respectively. The median annual hospital-level AC rate was 17.2 with inter-hospital variation ranging from 12.7 (quartile 1) to 24.1 (quartile 3) per 100 discharges, Figure 1. Similarly, the PAC rates varied among the ACHs with a median of 7.1 and inter-hospital variation ranging from 4.6 (quartile 1) to 10.5 (quartile 3) per 1,000 PDs, Figure 2. In multivariable analysis, no temporal trends in AC rates were detected (rate ratio (RR) 1.01; 95% confidence interval (CI): 0.99–1.02). However, PAC rates decreased 6.3% annually (RR 0.937; 95% CI: 0.93–0.95). Factors significantly associated (p&lt; 0.02) with PAC rates were discharge month, teaching status, bed size, and region. For AC, significant associations (p&lt; 0.0001) were discharge month and region.

Conclusion
Between 2012 and 2017, the rate of AC remained unchanged, but PAC rates decreased significantly. Factors driving this trend are unknown, but potential explanations include changes in culturing practices and/or decreases in hospital-onset urinary tract infections. Understanding factors related to the decrease and the impact on patient outcomes warrants further study.

Disclosures
All Authors: No reported disclosures
1482. Local validation of the drug resistance in pneumonia clinical prediction score at a large academic medical center and a community hospital
Authors: Reinhard Jennifer L , Elshaboury Ramy H , Hayes Bryan D , Mallada Jason , Paras Molly L , Bidell Monique R , Adamsick Meagan L , Gandhi Ronak G 
Published: January 2021

Abstract

Background
Community-acquired pneumonia (CAP) is responsible for ~1 million emergency department (ED) visits yearly and the leading cause of infection-related deaths. Given that increasing antibiotic resistance rates complicate appropriate empiric antibiotic selection, clinicians may benefit from tools to help identify patients at risk for drug-resistant pathogens (DRPs). Limitations of traditional tools, such as healthcare-associated pneumonia criteria (HCAP), have led to development of novel scoring tools such as the drug resistance in pneumonia (DRIP) score. Webb et al. showed the DRIP score was more predictive of CAP caused by DRPs than HCAP criteria. The objective of this study was to validate the DRIP score in a local population of hospitalized patients at an academic and a community medical center.

Methods
Patients who presented to the ED between May 2017 and May 2019 were included in this retrospective review. Patients were included if they were ≥ 18 years diagnosed with CAP by radiographic evidence with respiratory culture positivity and susceptibility results. Exclusion criteria were: presence of non-bacterial non-respiratory pathogens, patients with cystic fibrosis, lung transplant or systemic co-infections. The primary outcome was validation of the DRIP score by comparing the sensitivity, specificity, negative and positive predictive values (NPV/PPV) to the derivation and validation study by Webb et al. Secondary outcomes were the percentage of CAP cases with DRPs and the predictability of DRP using the DRIP score versus HCAP criteria.

Results
A total of 164 patients were included; 60.4% were male with a median age of 70 years. The primary outcome shown in Table 1 demonstrated similar sensitivity, specificity, NPV, and PPV of the DRIP score to those in the study by Webb et al. Staphylococcus aureus (32.9%) and Streptococcus pneumoniae (27.4%) were the most commonly isolated pathogens and CAP due to DRPs occurred in 30.5% of patients. The DRIP score also demonstrated improved performance in predicting DRPs in CAP compared to the HCAP Criteria as shown in Table 2.
Table 1. DRIP Score Validation

Table 2. Predictability of the DRIP score vs. HCAP criteria

Conclusion
Our results further validate the DRIP score derived by Webb et al. in predicting DRPs in CAP. These results encourage a local prospective evaluation of the DRIP score as an antimicrobial stewardship tool.

Disclosures
All Authors: No reported disclosures
1492. Targeted Substitution of Omadacycline in Place of Standard of Care for CABP Treatment is Associated with a Risk Reduction of Clostridioides difficile Infection and Financial Cost Savings in the Acute Care Setting
Authors: Rodriguez Mauricio , Chitra Surya , Wright Kelly , Lodise Thomas 
Published: January 2021

Abstract

Background
Real-world evidence studies indicate that around 3% of hospitalized patients with community-acquired pneumonia (CAP) develop Clostridioides difficile infection (CDI; Chalmers et al, J Infect 2016;73:45–53). Factors associated with increased CDI risk include Davis risk score (DRS) ≥ 6, and treatment with high-risk antibiotics such as fluroquinolones (FQ) and ceftriaxone (CTX). Omadacycline (OMC) is indicated for the treatment of community-acquired bacterial pneumonia (CABP) and has demonstrated a low propensity to induce CDI in preclinical and clinical studies. In the phase 3 OPTIC study, 2% of CABP patients who received moxifloxacin (MOX) developed CDI vs 0% for OMC (Stets et al, N Engl J Med 2019;380:517–27); 14% of MOX patients with DRS ≥ 6 developed CDI vs 0% in the OMC group (Table 1; Figure 1). We assessed the economic impact of substituting current CABP treatment (FQ and CTX) with OMC for hospitalized CABP patients with DRS ≥ 6.
Table 1

Figure 1

Methods
A deterministic healthcare-decision analytic model was performed. Only excess costs associated with each treatment were considered. Base-case model inputs were: yearly CAP admission in US, prevalence of CAP patients with DRS ≥ 6, CDI risk for CAP patients with DRS ≥ 6 with current CABP treatments, CDI costs (initial and recurrent), and OMC cost (Table 2). Efficacy and safety of treatments were assumed to be equal. CDI risk of 0% was assumed for OMC. Costs are reported as USD.
Table 2

Results
For patients with CABP, total CDI costs were $738M, with first-episode costs of $489M plus recurrence costs of $249M. The cost of 5 days (mean hospital length of stay for CABP) of OMC was $207M. Use of OMC for the estimated 100,000 CABP patients with DRS ≥ 6 would result in a potential cost saving of up to $531M for this patient population, assuming CDI risk of 0% with OMC. As CDI is a risk from any antibiotic use, cost savings can be achieved when OMC is used in place of high-risk antibiotics patients when CDI risk rates exceed 3.9%.

Conclusion
Our findings suggest prioritizing use of omadacycline over current CABP treatments in hospitalized CABP with a DRS ≥ 6 may substantially reduce attributable CDI costs. These results can serve as a basis for stewardship interventions to reduce hospital CDI rates and associated costs.

Disclosures
Mauricio Rodriguez, PharmD, BCPS, BCCCP, BCIDP, Paratek Pharmaceuticals, Inc. (Employee) Surya Chitra, PhD, Paratek Pharmaceuticals, Inc. (Consultant) Kelly Wright, PharmD, Paratek Pharmaceuticals, Inc. (Employee, Shareholder) Thomas Lodise, PharmD, PhD, Paratek Pharmaceuticals, Inc. (Consultant)
1493. The Incremental Burden of Nontuberculous Mycobacterial Lung Disease (NTMLD) among Patients with chronic obstructive pulmonary disease (COPD): Hospitalizations and ER Visits among US Medicare Beneficiaries
Authors: Wang Ping , Hassan Mariam , Chatterjee Anjan 
Published: January 2021

Abstract

Background
NTMLD is a rare mycobacterial infection characterized by worsening lung function and increased healthcare resource burden. Many patients with NTMLD have comorbid respiratory diseases such as COPD. Management of NTMLD in patients with COPD may not get adequate attention as clinical management of COPD is often prioritized. There is a lack of data quantifying the incremental burden of NTMLD among patients with COPD. We assessed the incremental burden of NTMLD in patients with comorbid COPD by comparing their healthcare resource utilization (HCRU), in terms of hospitalizations and emergency room (ER) visits, to matched COPD patients without NTMLD.

Methods
A retrospective cohort study was conducted using the US Medicare claims database (2010-2017). COPD patients with NTMLD were matched 1:3 to COPD patients without NTMLD (controls) by age and gender. HCRU was assessed in terms of hospitalizations (all-cause, respiratory related and COPD related) as well as ER visits (with and without subsequent hospitalization) over a 12-month follow-up period. Incremental burden of NTMLD was assessed by comparing the HCRU between COPD patients with NTMLD and controls using univariate and multivariate analyses adjusting for baseline comorbidities.

Results
A total of 4,010 COPD patients with NTMLD were matched to 12,030 controls. In univariate analyses, a significantly higher proportion of COPD patients with NTMLD had hospitalizations and ER visits compared to controls (Fig 1(A)); the number of hospitalizations and ER visits were also higher among patients with NTMLD (Fig 2(A)). This incremental burden was also reflected in subsequent multivariate analyses after adjusting for baseline comorbidities. As an example, respiratory-related hospitalizations in COPD patients with NTMLD had Odds Ratio of 2.5 (95%CI 2.2-2.7) and Incident Rate Ratio (IRR) of 2.3 (95%CI 2.1-2.4) compared to controls (Fig 1(B), 2(B)).
Figure 1: Proportion of Patients (A) and Odds Ratio (B) of Hospitalizations and ER Visits over a 12-month follow-up period among COPD patients with NTMLD vs. matched COPD patients without NTMLD.

Figure 2: Per Patient Rate (A) and Incidence Rate Ratio (B) of Hospitalization and ER Visits over a 12-month follow-up period among COPD patients with NTMLD vs. matched COPD patients without NTMLD.

Conclusion
COPD patients with NTMLD have a significantly higher disease burden due to hospitalizations and ER visits compared to COPD patients without NTMLD. These findings suggest the substantial incremental burden that NTMLD adds to existing COPD in patients and highlight the urgent need for attention and appropriate management.

Disclosures
Ping Wang, PhD, Insmed Incorporated (Employee) Mariam Hassan, PhD, B. Pharm, Insmed Incorporated (Employee) Anjan Chatterjee, MD, MPH, Insmed Incorporated (Employee)
1494. Validation of Methicillin-Resistant Staphylococcus aureus (MRSA) Risk Factors in Predicting MRSA Community-Acquired Pneumonia at an Academic Medical Center
Authors: Arieno Joelle , Seabury Robert , Steele Jeffrey , Darko William , Miller Christopher , Probst Luke A , Riddell Scott W , Kufel Wesley D 
Published: January 2021

Abstract

Background
The 2019 Infectious Diseases Society of America community-acquired pneumonia (CAP) guidelines recommend anti-methicillin-resistant Staphylococcus aureus (MRSA) therapy in patients with CAP based on previously identified risk factors for MRSA with an emphasis on local epidemiology and institutional validation of risk. Thus, we sought to assess the ability of guideline-recognized risk factors to predict MRSA CAP at our institution.

Methods
This was a single-center, retrospective cohort study from January 2016 to March 2020. Patients were included if they were &gt;18 years old, diagnosed with CAP, and had a MRSA nasal screen and a respiratory culture obtained on admission. Patients were excluded if CAP diagnosis was not met, respiratory cultures were not obtained within 48 hours of antibiotic initiation, or they had cystic fibrosis. Sensitivity, specificity, negative predictive value, positive predictive value, and likelihood ratios (LR) were calculated using Vassar Stats 2019. Pre/post-test odds and pre/post-test probabilities were calculated using Microsoft Excel 2019.

Results
Of 705 screened patients, 221 were included. MRSA prevalence in CAP patients at our institution was 3.6%. History of MRSA isolated from a respiratory specimen had high specificity (98%), high positive LR of 20 (95% CI 5.3 – 74.8), and high post-test probability of 42.8%. Receipt of IV antibiotics during hospitalization within the past 90 days had a positive LR of 1.9 (95% CI 0.74 – 4.84). A positive MRSA nasal screen on admission had a positive LR of 6.9 (95% CI 4.0 – 12.1), negative LR 0.28 (95% CI 0.08 – 0.93), positive post-test probability of 20.7%, and negative post-test probability of 1.04%.

Conclusion
Our study utilized institutional data to validate guideline-recognized risk factors for MRSA CAP specifically at our institution. Risk factors including history of MRSA isolated from a respiratory specimen, and positive post-admission MRSA nasal screen were validated as significant risk factors; receipt of IV antibiotics during hospitalization within the past 90 days was not shown to be a risk factor for MRSA CAP based on our institutional data. Validated risk factors may help providers discern which patients with CAP at our institution would benefit most from empiric MRSA treatment.

Disclosures
Jeffrey Steele, PharMD, Paratek Pharmaceuticals (Advisor or Review Panel member) Wesley D. Kufel, PharmD, Melinta (Research Grant or Support)Merck (Research Grant or Support)Theratechnologies, Inc. (Advisor or Review Panel member)
1496. Aspergillosis Complicating Severe Respiratory Syncytial Virus (RSV) in ICU Patients: A Retrospective Cohort Study
Authors: Nam Hannah , Ison Michael G 
Published: January 2021

Abstract

Background
There are recent reports that identify severe influenza pneumonia as an independent risk factor for the development of invasive pulmonary aspergillosis (IPA), even in patients without immunocompromise. We aimed to understand the incidence of IPA as well as other coinfections over multiple seasons in patients with RSV pneumonia in the intensive care unit (ICU).

Methods
A retrospective cohort study was conducted in a single center in Chicago. Data was collected over 9 seasons (January 2009-March 2018) from adult patients admitted to the ICU at a large urban tertiary care center with severe RSV pneumonia. Patients were included if they had a positive RSV PCR test, older than 18 years, admitted to the ICU with acute respiratory failure, and had pulmonary infiltrates on imaging. IPA was defined per both the EORTC/MSG criteria as well as the revised AspICU criteria (Schauwvlieghe et al). Descriptive statistics were calculated. In univariable analysis, we compared categorical variables by Fisher’s exact test and Chi-square test, continuous variables by Wilcoxon Rank Sum where appropriate.

Results
Of 224 patients admitted to the ICU with RSV (median ICU LoS 10.5 d), IPA was diagnosed in 8 (3.5%). Patients diagnosed with IPA had an increased LoS in the hospital (23.7 days vs. 11.6 days, p=0.01). Although the mortality was numerically higher (3, 37.5% vs 26, 17.9%) this was statistically not significant). History of hematological malignancy, stem cell transplant, and neutropenia were significant factors in the development of IPA. Those with lung disease had significantly lower rates of IPA. All patients with IPA were treated with voriconazole. Other coinfections among RSV-infected ICU patients included bacterial (21, 13.7%), viral (10, 6.5%), and non-IPA fungal (13, 8.5%) pathogens.
Baseline Characteristics and Mortality/Morbidity

Patient Characteristics in Invasive Pulmonary Aspergillosis

Conclusion
Although IPA is relatively uncommon in patients admitted to the ICU with severe RSV pneumonia, patients with IPA had significant increased LOS and tended to have underlying host factors. Other coinfections with bacterial, viral, and non-IPA fungal pathogens are common in those with severe RSV pneumonia.

Disclosures
Michael G. Ison, MD MS, AlloVir (Consultant)