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Background Ceftazidime/avibactam (CZA) and ceftolozane-tazobactam (CT) are new additions to the antibiotic armamentarium with activity against gram-negative pathogens, most notably drug-resistant Pseudomonas aeruginosa (PSA). The purpose of this study was to compare the in vitro activity of CZA and CT against a large real-world sample of clinical isolates of PSA displaying different phenotypes of resistance to conventional β-lactams at an institution where both CZA and CT are routinely tested on all isolates. Methods All cultures from patient infections with PSA from May 2018 to February 2019 at Michigan Medicine were included. Minimum inhibitory concentrations (MICs) for all β-lactams were determined using TREK broth microdilution panels and isolates were considered susceptible to CZA if the MIC was ≤8 mg/L and CT if the MIC was ≤4 mg/L. Results A total of 2,972 isolates of PSA from clinical specimens were included. Table 1 compares CZA and CT susceptibility, MIC50, MIC90, and MIC range for all isolates including those displaying resistance to various β-lactams. Among all isolates of PSA, CZA (96.2% susceptible) was slightly more active than CT (94.2%) and both agents were ~10% more active than the closest comparator (ceftazidime, 86.6%). In vitro activity of cefepime, piperacillin/tazobactam, and meropenem were 84.8%, 78%, and 80.3%, respectively. The activity of both CZA and CT dropped significantly among isolates with pan-β-lactam resistance (i.e., resistance to all conventional anti-pseudomonal β lactams, PBR) but CZA remained more active than CT (59.4% vs. 41.5%, P < 0.001). Of isolates displaying resistance to CT, 84 (48.6%) were susceptible to CZA. However, of those with resistance to CZA, only 24 (21.2%) were susceptible to CT (Table 2). Conclusion CZA was the most active β-lactam against PSA isolates at Michigan Medicine. Among PSA with PBR, CZA demonstrated superior activity compared with CT. Additionally, a significant number of isolates with resistance to CT were susceptible to CZA. Our findings are unique compared with other published reports where CT has consistently demonstrated greater activity than CZA against resistant P. aeruginosa and suggest routine testing of both CT and CZA should occur. Disclosures All authors: No reported disclosures.

Background Pneumonia remains a leading cause of hospitalization and accounts for significant antibiotic use. This study aims to evaluate the impact of bundled antimicrobial stewardship program (ASP) interventions, including procalcitonin and surveillance cultures, on broad-spectrum antimicrobial use in patients with suspected pneumonia. Methods This is a pre-post, quasi-experimental study conducted at Michigan Medicine. During the intervention period, an ASP member reviewed adult patients admitted to 3-floor medical services with antibiotics initiated for suspected pneumonia. The ASP member (1) recommended the use of procalcitonin when clinically appropriate, (2) used institutional guidelines to guide empiric antibiotic selection based on risk for drug-resistant pathogens, and (3) ordered a methicillin-resistant Staphylococcus aureus (MRSA) surveillance culture in patients receiving empiric anti-MRSA therapy. The primary endpoint was anti-MRSA and anti-pseudomonal (PSA) antibiotic use measured as days of therapy (DOT) per 1000 days-present on the services of interest. Antibiotic use and clinical data were extracted from an electronic database. Pneumonia diagnosis codes were used to identify the study population. Results A total of 549 patients were included: 310 in the pre-intervention (December 1/2017 - 3/31/2018) and 239 in the intervention (December 1/2018 - 3/31/2019) periods. Baseline demographics were similar between groups (Table 1). Less than 15% of patients had a microbiological diagnosis via respiratory culture in both study periods (Table 2). Respiratory cultures were ordered less commonly in the intervention period; however, the rate of culture positivity was higher (28% vs. 48%, P < 0.01). Process measures improved in the intervention period with an increase in the proportion of patients with MRSA surveillance cultures (13% vs. 39%, P < 0.01) and procalcitonin monitoring (77% vs. 83%, P = 0.07). Compared with the pre-intervention period, anti-MRSA antibiotic use decreased from 172 to 158 DOT per 1000 days-present (Δ -8%) and the use of anti-PSA antibiotics decreased from 348 to 316 DOT per 1000 days present (Δ -9%). Conclusion The implementation of an ASP-led pneumonia bundle led to reductions in anti-MRSA and anti-PSA antibiotic use. Disclosures All authors: No reported disclosures.

Purpose: The goal of this research was to examine spatial access to primary care physicians in Appalachia using both traditional access measures and the 2-step floating catchment area (2SFCA) method. Spatial access to care was compared between urban and rural regions of Appalachia. Methods: The study region included Appalachia counties of Pennsylvania, Ohio, Kentucky, and North Carolina. Primary care physicians during 2008 and total census block group populations were geocoded into GIS software. Ratios of county physicians to population, driving time to nearest primary care physician, and various 2SFCA approaches were compared. Results: Urban areas of the study region had shorter travel times to their closest primary care physician. Provider to population ratios produced results that varied widely from one county to another because of strict geographic boundaries. The 2SFCA method produced varied results depending on the distance decay weight and variable catchment size techniques chose. 2SFCA scores showed greater access to care in urban areas of Pennsylvania, Ohio, and North Carolina. Conclusion: The different parameters of the 2SFCA method—distance decay weights and variable catchment sizes—have a large impact on the resulting spatial access to primary care scores. The findings of this study suggest that using a relative 2SFCA approach, the spatial access ratio method, when detailed patient travel data are unavailable. The 2SFCA method shows promise for measuring access to care in Appalachia, but more research on patient travel preferences is needed to inform implementation.

Background Almost 50% of pregnancies in the United States are unwanted or mistimed. Notably, just over one-half of unintended pregnancies occurred when birth control was being used, suggesting inappropriate or poor use or contraceptive failure. About two-thirds of all women who are of reproductive age use contraceptives, and oral hormonal contraceptives remain the most common contraceptive method. Often, contraceptive products are obtained in community pharmacies. The purpose of this study was to determine whether a pharmacy-based intervention would impact sales of contraceptive products in pharmacies. Methods This study was conducted in Iowa and used a quasi-experimental design including 55 community pharmacies (independent and grocery) in 12 counties as the intervention and 32 grocery pharmacies in 10 counties as a comparison group. The passive intervention was focused towards 18–30 year old women who visited community pharmacies and prompted those of childbearing age to “plan your pregnancy” and “consider using birth control”. The intervention was delivered via educational tri-fold brochures, posters and ‘shelf talkers.’ Data sources for evaluation were contraceptive sales from intervention and comparison pharmacies, and a mixed negative binomial regression was used with study group*time interactions to examine the impact of the intervention on oral contraceptive and condom sales. Data from 2009 were considered baseline sales. Results From 2009 to 2011, condom sales decreased over time and oral contraceptives sales showed no change. Overall, the units sold were significantly higher in grocery pharmacies than in independent pharmacies for both contraceptive types. In the negative binomial regression for condoms, there was an overall significant interaction between the study group and time variables (p = 0.003), indicating an effect of the intervention, and there was a significant slowing in the drop of sales at time 3 in comparison with time 1 (p