Rethinking Perioperative Antibiotic Prophylaxis for Low-Risk Head and Neck Procedures

OBJECTIVE

For true clean-contaminated head and neck procedures, the literature supports ≤24 hours of perioperative antibiotics. However, there are certain otolaryngology procedures with low surgical site infection (SSI) risk for which there is negligible benefit from antibiotic prophylaxis. The objective of this evaluation was to describe antibiotic use and adherence to evidence-based institutional guidelines in low-risk head and neck procedures.

METHODS

This was a single-center, retrospective cohort study of patients undergoing low-risk clean-contaminated head and neck procedures wherein antibiotic prophylaxis was not indicated, based on evidence-based institutional guidelines.

RESULTS

Among the 291 included patients, perioperative antibiotics were unnecessarily administered in 29% of patients. Among patients who received antibiotics, 76% received preoperative antibiotics and 41% received postoperative antibiotics, for a median duration of 7 days. There were no significant differences in SSIs, mortality, and length of stay for those receiving perioperative antibiotics versus those not receiving perioperative antibiotics.

CONCLUSION

These data highlight the need for antibiotic stewardship interventions and partnerships between antibiotic stewardship teams and surgical services.

Microbiology of infection-related complications after transrectal ultrasound-guided prostate biopsy

INTRODUCTION

The objective of this study was to describe the incidence, microbiology, and risk factors related to infectious complications after transrectal prostate biopsies.

METHODS

This was a single-center, retrospective cohort study of patients undergoing prostate biopsies. Throughout the study period, the institutional standard for antibiotic prophylaxis was cephalexin and ciprofloxacin. Due to the desire to limit fluoroquinolone use, the ciprofloxacin duration of therapy was reduced from 48 to 24 hours in the middle of the study period. The primary outcome was the incidence of infection-related complications, defined as a urinary tract infection or bacteremia within 30 days post-procedure.

RESULTS

A total of 1471 transrectal prostate biopsies were included. All patients received antibiotic prophylaxis, with 86.1% (1268/1472) of patients receiving both ciprofloxacin and cephalexin. The incidence of infection-related complications was 1.6% (24/1471). Four patients experienced bacteremia, all of which were due to E. coli and all of these patients had received antibiotic prophylaxis with an active antibiotic. The use of ciprofloxacin was associated with a lower risk of infection-related complications (odds ratio [OR] 0.20, 95% confidence interval [CI] 0.07, 0.55). Bacteriuria within one year prior to the procedure was associated with increased risk of infection-related complications (OR 4.77, 95% CI 1.34, 16.93). Four (0.3%) patients experienced an antibiotic-related adverse event.

CONCLUSIONS

We observed a low rate of infection-related complications and antibiotic-related adverse events in the setting of antibiotic prophylaxis with ciprofloxacin and cephalexin for 24 hours, without pre-procedure rectal culture screening. Investigation into procedural or host factors may uncover opportunities to further reduce infection-related complications.

Impact of the sequential implementation of a pharmacy-driven methicillin-resistant Staphylococcus aureus (MRSA) nasal-swab ordering policy and vancomycin 72-hour restriction protocol on standardized antibiotic administration ratio (SAAR) data for antibiotics used for resistant gram-positive infections

OBJECTIVE

Vancomycin is often initiated in hospitalized patients; however, it may be unnecessary or continued for longer durations than needed. Oversight of all vancomycin orders may not be feasible with widespread prescribing and strategies to enlist other clinicians to serve as stewards of vancomycin use are needed. We implemented 2 sequential interventions: a protocol in which the pharmacist orders MRSA nasal swab followed by a protocol requiring approval from pharmacists to continue vancomycin for >72 hours.

METHODS

In this single-center, retrospective, quasi-experimental study, we evaluated vancomycin use after implementation of a pharmacy-driven MRSA nasal-swab ordering protocol and a vancomycin 72-hour restriction protocol. The primary outcome was the change in the standardized antibiotic administration ratio (SAAR) for antibacterial agents for resistant gram-positive infections. We also evaluated the impact on antibiotic utilization.

RESULTS

Following the MRSA swab protocol, the SAAR decreased from 1.26 to 1.13 (P < .001; 95% confidence interval [CI], 1.16-1.25). After the 72-hour approval process, the SAAR was 0.96 (P < .001; 95% CI, 1.0-1.12). Vancomycin utilization decreased from 138.9 to 125.3 days of therapy per 1,000 patient days following the MRSA swab protocol (P < .001) and to 112.7 (P < .001) following the 72-hour approval protocol. Interrupted time-series analysis identified a similar rate of decline in utilization following the 2 interventions (-0.3 and -0.5; P = .16). Both interventions combined resulted in a significant reduction (-1.5; P < .001).

CONCLUSION

Implementation of a pharmacist-driven MRSA nasal-swab ordering protocol, followed by a 72-hour approval protocol, was associated with a significant reduction in the SAAR for antibiotics used in the treatment of resistant gram-positive infections and a reduction in vancomycin utilization. Leveraging the oversight of primary service clinical pharmacists through these protocols proved to be an effective strategy.

When is vancomycin prophylaxis necessary? Risk factors for MRSA surgical site infection

Background

The 2022 SHEA/IDSA/APIC guidance for surgical site infection (SSI) prevention recommends reserving vancomycin prophylaxis to patients who are methicillin-resistant Staphylococcus aureus (MRSA) colonized. Unfortunately, vancomycin prophylaxis remains common due to the overestimation of MRSA risk and the desire to cover MRSA in patients with certain healthcare-associated characteristics. To optimize vancomycin prophylaxis, we sought to identify risk factors for MRSA SSI.

Methods

This was a single-center, case-control study of patients with a postoperative SSI after undergoing a National Healthcare Safety Network operative procedure over eight years. MRSA SSI cases were compared to non-MRSA SSI controls. Forty-two demographic, medical, and surgical characteristics were evaluated.

Results

Of the 441 patients included, 23 developed MRSA SSIs (rate = 5.2 per 100 SSIs). In the multivariable model, we identified two independent risk factors for MRSA SSI: a history of MRSA colonization or infection (OR, 9.0 [95% CI, 1.9-29.6]) and hip or knee replacement surgery (OR, 3.8 [95% CI, 1.3-9.9]). Hemodialysis, previous hospitalization, and prolonged hospitalization prior to the procedure had no measurable association with odds of MRSA SSI.

Conclusions

Patients with prior MRSA colonization or infection had 9-10 times greater odds of MRSA SSI and patients undergoing hip and knee replacement had 3-4 times greater odds of MRSA SSI. Healthcare-associated characteristics, such as previous hospitalization or hemodialysis, were not associated with MRSA SSI. Our findings support national recommendations to reserve vancomycin prophylaxis for patients who are MRSA colonized, as well as those undergoing hip and knee replacement, in the absence of routine MRSA colonization surveillance.

Treatment options for severe or refractory mpox virus infection in patients with advanced HIV

The Centers for Disease Control and Prevention (CDC) published a health advisory on the occurrence of severe cases of mpox in immunocompromised patients, namely those with advanced HIV. Treatment options are limited, and very little is known about how to optimally treat patients with severe disease. Herein we describe two cases of severe mpox in Chicago in the setting of advanced HIV and provide suggested guidance for managing cases of severe disease in immunocompromised patients based available data, CDC recommendations, and our experience managing these patients.

1842. Intravenous to Oral Antibiotic Stepdown for Uncomplicated Streptococcal Bacteremia

Background

Historically, intravenous (IV) antibiotics have been the standard of care for the treatment of bloodstream infections (BSIs). IV antibiotic use predisposes patients to line-related complications and is associated with increased length of stay (LOS) and treatment costs as compared to oral (PO) antibiotics. The purpose of this study was to compare the efficacy and safety of IV therapy versus PO stepdown for uncomplicated Streptococcal BSIs.

Methods

This single-center, retrospective, non-inferiority study included adults who had Streptoccoccus spp. in blood cultures with susceptibilities reported, < 48 hours of positive blood cultures, and were treated for the BSI. Patients were excluded if they had polymicrobial bacteremia, mortality prior to treatment completion, unattainable source control, or a complicated infection. The primary outcome was clinical success, defined as absence of infection recurrence, infection-related readmission, and infection-related mortality at 90 days. Secondary outcomes included individual components of composite endpoint, microbiological success, LOS, IV-line associated complications, and antibiotic-associated adverse events.

Results

Of 79 patients included, 36 patients (45.6%) received IV for the full course of therapy and 43 (54.4%) received PO stepdown. Baseline characteristics were similar between groups. The most common sources were skin and soft tissue (34.6%) and oropharyngeal (13.6%). The median duration of IV therapy in PO stepdown patients was 4.4 days (IQR 2.7 – 6.9). Amoxicillin/clavulanate (44%) and cefdinir (24%) were the most common PO agents. Clinical success occurred in 94% of IV only patients and 91% of PO stepdown patients (p = 0.573). No infection-related deaths or recurrences occurred. Line complications were more frequent in patients receiving IV compared to PO stepdown therapy (14% vs. 0%, p = 0.015). LOS was lower in the PO stepdown group (11 vs. 6 days, p < 0.001).

Conclusion

This study strengthens the hypothesis that PO stepdown therapy may be non-inferior to IV therapy for clinical success with a trend towards decreased LOS and line complications. However, this study was not powered to meet statistical significance. We are collaborating with several other centers to determine the true impact of this intervention.

Disclosures

All Authors: No reported disclosures.

959. It Takes a Village: Reducing Empiric Vancomycin Use by Leveraging Primary Team Pharmacist Oversight of a 72-hour Approval Process

Background

Vancomycin is often initiated empirically in hospitalized patients for broad spectrum gram-positive coverage, however in many cases it is initiated unnecessarily and/or continued empirically for longer durations than necessary. Strategies to facilitate timely discontinuation of vancomycin when unnecessary may reduce antibiotic toxicity (e.g. nephrotoxicity) and the development of bacterial resistance. In large hospital systems, it may not be feasible for stewardship programs to implement prior authorization requirements or prospective audit/feedback for all vancomycin orders. Novel strategies to enlist other clinicians to serve as stewards of antibiotic use are needed.

Methods

On February 1, 2020, we implemented a protocol requiring providers to obtain approval from the primary team pharmacist to continue empiric vancomycin regimens >72 hours. Primary team pharmacists were provided a list of appropriate indications for vancomycin continuation. After 72 hours, the pharmacist placed a note describing the approved indication or if ASP or ID consult was obtained. We evaluated the standardized antibiotic administration ratio (SAAR) for antibacterial agents for resistant gram-positive infections for FY2019 (pre-protocol) and FY2020 (post-protocol) to assess the impact of this intervention. Vancomycin utilization was also evaluated in days of therapy (DOT)/1000 patient days during both time periods.

Results

The SAAR for antibacterial agents for resistant gram-positive infections for FY2019 was 1.17 and FY2020 was 1.04 (95% CI (0.87, 0.91), p-value < 0.001). A significant reduction in SAAR was observed in patients admitted to the ICU and floor (Figure 1). Overall vancomycin utilization according to days of therapy/1000 patient days was reduced from 111.13 (FY2019) to 104.08 (FY2020).

Conclusion

Leveraging the oversight of primary team pharmacists proved to be an effective strategy to reduce empiric vancomycin durations of therapy. Following the implementation of a 72-hour approval protocol with primary team pharmacist oversight, we observed a significant reduction in the SAAR for antibacterials for resistant gram-positive infections with a corresponding reduction in vancomycin utilization.

Disclosures

All Authors: No reported disclosures.

1326. Possible Predictors of Coinfection in COVID-19: Making a Difficult Diagnosis

Background

Coinfection with COVID-19 and a secondary pathogen contributes to morbidity and mortality. Despite its contribution to outcomes, diagnosing coinfection is challenging and no predictive tools have been established. To better assess risk factors for coinfection, we performed a review of all patients hospitalized for COVID-19 in our institution and evaluated them for candidate predictors of coinfection.

Methods

Medical records were reviewed in all patients admitted with COVID-19 at University of Chicago Medical Center between March 1, 2020 and April 18, 2020. Those identified as having coinfection were compared to those without coinfection. Secondary review was performed for characteristics of the coinfection, including diagnosis, microbiology, drug resistance, and nosocomial acquisition.

Results

401 patients were included in the study, the mean age was 60 years (SD-17), 29% had severe disease, and 13% died. At least one test for coinfection was performed in 99% of patients. Coinfection was identified in 15% (72/401) of patients. Coinfection was associated with older age, disease severity, and hospital complications, such as DVT/PE, AKI, and delirium. [Table 1] No symptom, non-microbiologic test, radiograph, or preexisting condition was associated with coinfection. Dyspnea, chest pain, and obesity were more common in those without coinfection. 74% received antibiotics. The most common sites for coinfection were urinary 33%, lower respiratory 26%, and blood 24%. [Table2] Bacteria were most frequently recovered (82%). The most commonly recovered pathogens were Enterobacterales (42%), Staphylococcus aureus (12%), and Pseudomonas (4%). 42% of the infections were hospital acquired, 16% caused by MDRO, and 13% were catheter or ventilator associated.

Table 1. Clinical Characteristics Associated with Coinfection

Abbreviations: sd, standard deviation; WBC, white blood cell count; CRP, C-reactive protein; COPD, chronic obstructive pulmonary disease; ARDS, acute respiratory distress syndrome; DVT, deep venous thrombosis; PE, pulmonary embolism; MI, myocardial infarction; AKI, acute kidney injury

Table 2. Characteristics of Coinfection

Abbreviations: Cath, catheter; Vent, ventilator; Assoc, Associated; MDRO, Multiple Drug Resistant Organism

Conclusion

Coinfection in COVID-19 was most closely associated with age, COVID-19 disease severity, and complicated hospitalization. No presenting symptoms, non-microbiologic test, or radiograph was associated with coinfection, underscoring the challenge in diagnosing coinfection. A remarkable number of infections were hospital acquired, MDRO, and catheter/ventilator associated. Further prospective study on coinfection in COVID-19 is needed to guide diagnosis and treatment.

Disclosures

Renslow Sherer, MD, Gilead Sciences, Inc (Grant/Research Support)

Reducing the use of empiric antibiotic therapy in COVID-19 on hospital admission

BACKGROUND

Empiric antibiotics for community acquired bacterial pneumonia (CABP) are often prescribed to patients with COVID-19, despite a low reported incidence of co-infections. Stewardship interventions targeted at facilitating appropriate antibiotic prescribing for CABP among COVID-19 patients are needed. We developed a guideline for antibiotic initiation and discontinuation for CABP in COVID-19 patients. The purpose of this study was to assess the impact of this intervention on the duration of empiric CABP antibiotic therapy among patients with COVID-19.

METHODS

This was a single-center, retrospective, quasi-experimental study of adult patients admitted between 3/1/2020 to 4/25/2020 with COVID-19 pneumonia, who were initiated on empiric CABP antibiotics. Patients were excluded if they were initiated on antibiotics > 48 h following admission or if another source of infection was identified. The primary outcome was the duration of antibiotic therapy (DOT) prior to the guideline (March 1 to March27, 2020) and after guideline implementation (March 28 to April 25, 2020). We also evaluated the clinical outcomes (mortality, readmissions, length of stay) among those initiated on empiric CABP antibiotics.

RESULTS

A total of 506 patients with COVID-19 were evaluated, 102 pre-intervention and 404 post-intervention. Prior to the intervention, 74.5% (n = 76) of patients with COVID-19 received empiric antibiotics compared to only 42% of patients post-intervention (n = 170), p < 0.001. The median DOT in the post-intervention group was 1.3 days shorter (p < 0.001) than the pre-intervention group, and antibiotics directed at atypical bacteria DOT was reduced by 2.8 days (p < 0.001). More patients in the post-intervention group were initiated on antibiotics based on criteria consistent with our guideline (68% versus 87%, p = 0.001). There were no differences between groups in terms of clinical outcomes.

CONCLUSION

Following the implementation of a guideline outlining recommendations for initiating and discontinuing antibiotics for CABP among COVID-19 inpatients, we observed a reduction in antibiotic prescribing and DOT. The guideline also resulted in a significant increase in the rate of guideline-congruent empiric antibiotic initiation.

Community-acquired Coinfection in Coronavirus Disease 2019: A Retrospective Observational Experience

Community acquired co-infection in COVID-19 is not well defined. Current literature describes co-infection in 0-40% of COVID-19 patients. In this retrospective report, co-infection was identified in 3.7% of patients and 41% of patients admitted to intensive care (p<0.005). Despite infrequent co-infection, antibiotics were used in 69% of patients.

The effect of delays in second-dose antibiotics on patients with severe sepsis and septic shock

BACKGROUND

Early antibiotics are fundamental to sepsis management. Second-dose antibiotic delays were associated with increased mortality in a recent study. Study objectives include: 1) determine factors associated with delays in second-dose antibiotic administration; 2) evaluate if delays influence clinical outcomes.

METHODS

ED-treated adults (≥18 years; n = 1075) with severe sepsis or septic shock receiving ≥2 doses of intravenous antibiotics were assessed, retrospectively, for second-dose antibiotic delays (dose time > 25% of recommended interval). Predictors of delay and impact on outcomes were determined, controlling for MEDS score, 30 mL/kg fluids and antibiotics within three hours of sepsis onset, lactate, and renal failure, among others.

RESULTS

In total, 335 (31.2%) patients had delayed second-dose antibiotics. A total of 1864 second-dose antibiotics were included, with 354 (19.0%) delays identified by interval (delayed/total doses): 6-h (36/67) = 53.7%; 8-h (165/544) = 30.3%; 12-h (114/436) = 26.1%; 24-h (21/190) = 8.2%; 48-h (0/16) = 0%. In-hospital mortality in the timely group was 15.5% (shock-17.6%) and 13.7% in the delayed group (shock-16.9%). Increased odds of delay were observed for ED boarding (OR 2.54, 95% 1.81-3.55), shorter dosing intervals (6/8-h- OR 2.99, 95% CI 1.95-4.57; 12-h- OR 2.46, 95% CI 1.72-3.51), receiving 30 mL/kg fluids by three hours (OR 1.42, 95% CI 1.06-1.90), and renal failure (OR 2.57, 95% CI 1.50-4.39). Delays were not associated with increased mortality (OR 0.87, 95% CI 0.58-1.29) or other outcomes.

CONCLUSIONS

Factors associated with delayed second-dose antibiotics include ED boarding, antibiotics requiring more frequent dosing, receiving 30 mL/kg fluid, and renal failure. Delays in second-dose administration were not associated with mortality or other outcomes.

COVIDOSE: A Phase II Clinical Trial of Low-Dose Tocilizumab in the Treatment of Noncritical COVID-19 Pneumonia

Interleukin-6 (IL-6)-mediated hyperinflammation may contribute to the mortality of coronavirus disease 2019 (COVID-19). The IL-6 receptor-blocking monoclonal antibody tocilizumab has been repurposed for COVID-19, but prospective trials and dose-finding studies in COVID-19 have not yet fully reported. We conducted a single-arm phase II trial of low-dose tocilizumab in nonintubated hospitalized adult patients with COVID-19, radiographic pulmonary infiltrate, fever, and C-reactive protein (CRP) ≥ 40 mg/L. We hypothesized that doses significantly lower than the emerging standards of 400 mg or 8 mg/kg would resolve clinical and laboratory indicators of hyperinflammation. A dose range from 40 to 200 mg was evaluated, with allowance for one repeat dose at 24 to 48 hours. The primary objective was to assess the relationship of dose to fever resolution and CRP response. Thirty-two patients received low-dose tocilizumab, with the majority experiencing fever resolution (75%) and CRP decline consistent with IL-6 pathway abrogation (86%) in the 24-48 hours following drug administration. There was no evidence of a relationship between dose and fever resolution or CRP decline over the dose range of 40-200 mg. Within the 28-day follow-up, 5 (16%) patients died. For patients who recovered, median time to clinical recovery was 3 days (interquartile range, 2-5). Clinically presumed and/or cultured bacterial superinfections were reported in 5 (16%) patients. Low-dose tocilizumab was associated with rapid improvement in clinical and laboratory measures of hyperinflammation in hospitalized patients with COVID-19. Results of this trial provide rationale for a randomized, controlled trial of low-dose tocilizumab in COVID-19.

1346. Implementation of a Multidisciplinary 48 Hour Antibiotic Timeout in a Pediatric Population

Background

To meet the core elements required for antimicrobial stewardship programs, our institution implemented a pharmacy-led antibiotic timeout (ATO) process in 2017 and a multidisciplinary ATO process in 2019. An antibiotic timeout is a discussion and review of the need for ongoing empirical antibiotics 2-4 days after initiation. This study sought to evaluate both the multidisciplinary ATO and the pharmacy-led ATO in a pediatric population, compare the impact of each intervention on antibiotic days of therapy (DOT) to a pre-intervention group without an ATO, and to then compare the impact of the pharmacy-led ATO versus multidisciplinary ATO on antibiotic days of therapy (DOT).

Methods

This was a retrospective, pre-post, quasi-experimental study of pediatric patients comparing antibiotic DOT prior to ATO implementation (pre-ATO), during the pharmacy-led ATO (pharm-ATO), and during the multidisciplinary ATO (multi-ATO). The pre-ATO group was a patient sample from February-September 2016, prior to the initiation of a formal ATO. The pharmacy-led ATO was implemented from February-September 2018. This was followed by a multidisciplinary ATO led by pediatric residents and nurses from February-September 2019. Both the pharm-ATO and the multi-ATO were implemented as an active non-interruptive alert added to the electronic health record patient list. This alert triggered when new antibiotics had been administered to the patient for 48 hours, at which time, the responsible clinician would discuss the antibiotic and document their decision via the alert workspace. Pediatric patients receiving IV or PO antibiotics administered for at least 48 hours were included. The primary outcome was DOT. Secondary outcomes included length of stay (LOS) and mortality.

Results

1284 unique antibiotic orders (n= 572 patients) were reviewed in the pre-ATO group, 868 (n= 323 patients) in the pharm-ATO and 949 (n= 305 patients) in the multi-ATO groups. Average DOT was not significantly different pre vs post intervention for either methodology (Table 1). Mortality was similar between groups, but LOS was longer for both intervention groups (Table 1).

Impact of an ATO on DOT, Mortality and LOS

Conclusion

An ATO had no impact on average antibiotic DOT in a pediatric population, regardless of the ATO methodology.

Disclosures

All Authors: No reported disclosures

Remdesivir Use in the Setting of Severe Renal Impairment: A Theoretical Concern or Real Risk?

INTRODUCTION

Remdesivir (RDV) is FDA approved for COVID-19, but not recommended for patients with severe renal impairment (SRI, i.e. creatinine clearance < 30ml/min). Few studies have evaluated RDV in patients with SRI due to theoretical toxicity concerns.

METHODS

Hospitalized patients receiving RDV for COVID-19 between 5/1/2020-10/31/2020 were analyzed in a retrospective chart review. We compared incident adverse events (AEs) following RDV in patients with and without SRI, including hepatotoxicity, nephrotoxicity, any reported AE, mortality and length of stay.

RESULTS

A total of 135 patients received RDV, 20 patients had SRI. Patients with SRI were significantly older (70 vs. 54 years, p=0.0001). The incidence of possible AEs following RDV was 20% among those with SRI versus 11% without (p=0.26). LFT elevations occurred in 10% vs. 4% (p=0.28), and SCr elevations occurred in 20% vs. 6% (p=0.06) of patients with SRI versus those without, respectively. The LFT and SCr elevations were not attributed to RDV in either group. Mortality and length of stay were comparable and consistent with historical controls.

CONCLUSION

RDV AEs occurred infrequently with low severity and were not significantly different between those with and without SRI. While a higher percentage of patients with SRI experienced SCr elevations, 3 (75%) patients were in AKI prior to RDV. Overall, the use of RDV in this small series of patients with SRI appeared to be relatively safe, and the potential benefit outweighed the theoretical risk of liver or renal toxicity; however, additional studies are needed to confirm this finding.

IL-6 Inhibition in Critically Ill COVID-19 Patients Is Associated With Increased Secondary Infections

Background: Anti-inflammatory therapies such as IL-6 inhibition have been proposed for COVID-19 in a vacuum of evidence-based treatment. However, abrogating the inflammatory response in infectious diseases may impair a desired host response and pre-dispose to secondary infections. Methods: We retrospectively reviewed the medical record of critically ill COVID-19 patients during an 8-week span and compared the prevalence of secondary infection and outcomes in patients who did and did not receive tocilizumab. Additionally, we included representative histopathologic post-mortem findings from several COVID-19 cases that underwent autopsy at our institution. Results: One hundred eleven patients were identified, of which 54 had received tocilizumab while 57 had not. Receiving tocilizumab was associated with a higher risk of secondary bacterial (48.1 vs. 28.1%; p = 0.029 and fungal (5.6 vs. 0%; p = 0.112) infections. Consistent with higher number of infections, patients who received tocilizumab had higher mortality (35.2 vs. 19.3%; p = 0.020). Seven cases underwent autopsy. In three cases who received tocilizumab, there was evidence of pneumonia on pathology. Of the four cases that had not been given tocilizumab, two showed evidence of aspiration pneumonia and two exhibited diffuse alveolar damage. Conclusions: Experimental therapies are currently being applied to COVID-19 outside of clinical trials. Anti-inflammatory therapies such as anti-IL-6 therapy have the potential to impair viral clearance, pre-dispose to secondary infection, and cause harm. We seek to raise physician awareness of these issues and highlight the need to better understand the immune response in COVID-19.

Obesity is Associated with Increased Risk for Mortality Among Hospitalized Patients with COVID-19

OBJECTIVE

Obesity has been identified as a risk factor for severe coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 virus. This study sought to determine whether obesity is a risk factor for mortality among patients with COVID-19.

METHODS

The study was a retrospective cohort that included patients with COVID-19 between March 1 and April 18, 2020.

RESULTS

A total of 238 patients were included; 218 patients (91.6%) were African American, 113 (47.5%) were male, and the mean age was 58.5 years. Of the included patients, 146 (61.3%) had obesity (BMI > 30 kg/m² ), of which 63 (26.5%), 29 (12.2%), and 54 (22.7%) had class 1, 2, and 3 obesity, respectively. Obesity was identified as a predictor for mortality (odds ratio [OR] 1.7 [1.1-2.8], P = 0.016), as was male gender (OR 5.2 [1.6-16.5], P = 0.01) and older age (OR 3.6 [2.0-6.3], P < 0.0005). Obesity (OR 1.7 [1.3-2.1], P < 0.0005) and older age (OR 1.3 [1.0-1.6], P = 0.03) were also risk factors for hypoxemia.

CONCLUSIONS

Obesity was found to be a significant predictor for mortality among inpatients with COVID-19 after adjusting for age, gender, and other comorbidities. Patients with obesity were also more likely to present with hypoxemia.

Automatic ID Consultation for Inpatients With COVID-19: Point, Counterpoint, and a Single-Center Experience

There are many unknowns with regard to COVID-19 clinical management, including the role of Infectious Diseases Consultation (IDC). As hospitalizations for COVID-19 continue, hospitals are assessing how to optimally and efficiently manage COVID-19 inpatients. Typically, primary teams must determine when IDC is appropriate, and ID clinicians provide consultation upon request of the primary team. IDC has been shown to be beneficial for many conditions; however, the impact of IDC for COVID-19 is unknown. Herein, we discuss the potential benefits and pitfalls of automatic IDC for COVID-19 inpatients. Important considerations include the quality of care provided, allocation and optimization of resources, and clinician satisfaction. Finally, we describe how automatic IDC changed throughout the COVID-19 pandemic at a single academic medical center.

IL6 inhibition in critically ill COVID-19 patients is associated with increased secondary infections

BACKGROUND

Anti-inflammatory therapies such as IL-6 inhibition have been proposed for COVID-19 in a vacuum of evidence-based treatment. However, abrogating the inflammatory response in infectious diseases may impair a desired host response and predispose to secondary infections.

METHODS

We retrospectively reviewed the medical record of critically ill COVID-19 patients during an 8-week span and compared the prevalence of secondary infection and outcomes in patients who did and did not receive tocilizumab. Additionally, we included representative histopathologic post-mortem findings from several COVID-19 cases that underwent autopsy at our institution.

RESULTS

111 patients were identified, of which 54 had received tocilizumab while 57 had not. Receiving tocilizumab was associated with a higher risk of secondary bacterial (48.1% vs. 28.1%, p=0.029 and fungal (5.6% vs. 0%, p=0.112) infections. Consistent with higher number of infections, patients who received tocilizumab had higher mortality (35.2% vs. 19.3%, p=0.020). Seven cases underwent autopsy. In 3 cases who received tocilizumab, there was evidence of pneumonia on pathology. Of the 4 cases that had not been given tocilizumab, 2 showed evidence of aspiration pneumonia and 2 exhibited diffuse alveolar damage.

CONCLUSIONS

Experimental therapies are currently being applied to COVID-19 outside of clinical trials. Anti-inflammatory therapies such as anti-IL-6 therapy have the potential to impair viral clearance, predispose to secondary infection, and cause harm. We seek to raise physician awareness of these issues and highlight the need to better understand the immune response in COVID-19.

Late onset infectious complications and safety of tocilizumab in the management of COVID-19

Background

Tocilizumab (TCZ) has been used in the management of COVID‐19‐related cytokine release syndrome (CRS). Concerns exist regarding the risk of infections and drug‐related toxicities. We sought to evaluate the incidence of these TCZ complications among COVID‐19 patients.

Methods

All adult inpatients with COVID‐19 between 1 March and 25 April 2020 that received TCZ were included. We compared the rate of late‐onset infections (>48 hours following admission) to a control group matched according to intensive care unit admission and mechanical ventilation requirement. Post‐TCZ toxicities evaluated included: elevated liver function tests (LFTs), GI perforation, diverticulitis, neutropenia, hypertension, allergic reactions, and infusion‐related reactions.

Results

Seventy‐four patients were included in each group. Seventeen infections in the TCZ group (23%) and 6 (8%) infections in the control group occurred >48 hours after admission (P = .013). Most infections were bacterial with pneumonia being the most common manifestation. Among patients receiving TCZ, LFT elevations were observed in 51%, neutropenia in 1.4%, and hypertension in 8%. The mortality rate among those that received TCZ was greater than the control (39% versus 23%, P = .03).

Conclusion

Late onset infections were significantly more common among those receiving TCZ. Combining infections and TCZ‐related toxicities, 61% of patients had a possible post‐TCZ complication. While awaiting clinical trial results to establish the efficacy of TCZ for COVID‐19 related CRS, the potential for infections and TCZ related toxicities should be carefully weighed when considering use.

Infectious complications and drug‐related toxicities are concerns associated with TCZ use.

Among COVID‐19 patients presenting with a hyper‐inflammatory response receiving TCZ, 61% had a possible post‐TCZ complication.

Additional studies are needed to further evaluate the safety and efficacy of TCZ in the management of patients with COVID‐19.

Effect of IV Push Antibiotic Administration on Antibiotic Therapy Delays in Sepsis

OBJECTIVES

Timeliness of antibiotic administration is recognized as an important factor in reducing mortality associated with sepsis. According to guidelines, antibiotics should be administered within 1 hour of sepsis presentation and the Centers for Medicare & Medicaid Services mandates administration within 3 hours. This study evaluates the difference in time from sepsis diagnosis to first-dose completion of β-lactam antibiotics between IV push and IV piggyback administration.

DESIGN

Single-center, retrospective analysis.

SETTING

Urban, tertiary-care emergency department.

PATIENTS

Inclusion criteria were as follows: 1) adult patients (n = 274) diagnosed with severe sepsis or septic shock per Sepsis-2 criteria from September to November 2016 and from September to November 2017 and 2) received β-lactam antibiotic.

INTERVENTIONS

Initial β-lactam agent administered as either IV push or IV piggyback.

MEASUREMENTS AND MAIN RESULTS

Median time (interquartile range) from sepsis diagnosis to administration of a β-lactam antibiotic was 48 minutes (19-96 min) versus 72 minutes (8-180 min) and to administration of the complete broad-spectrum regimen was 108 minutes (66-144 min) versus 114 minutes (42-282 min) in the IV push (n = 143) versus IV piggyback (n = 131) groups, respectively. When controlling for time to sepsis diagnosis and other factors, IV push was associated with approximately 32-minute time savings to β-lactam (β = -0.60; 95% CI, -0.91 to -0.29) and approximately 32-minute time savings to broad-spectrum (β = -0.32; 95% CI, -0.62 to -0.02) antibiotic administrations. The IV push group was less likely to fail the goal of β-lactam antibiotics within 1 hour (44.6% vs 57.3%; odds ratio, 2.27; 95% CI, 1.34-3.86) and 3 hours (7.6% vs 24.5%; odds ratio, 4.31; 95% CI, 2.01-10.28) of sepsis diagnosis compared with IV piggyback. The IV push strategy did not affect mortality, need for ICU admission, or ICU length of stay. No adverse events, including infusion reactions, were found in either arm.

CONCLUSIONS

Use of an IV push strategy may safely facilitate more rapid administration of β-lactam antibiotics and may allow for better compliance with sepsis management guidelines.

COVIDOSE: Low-dose tocilizumab in the treatment of Covid-19

Background Interleukin-6 (IL-6)-mediated hyperinflammation may contribute to the high mortality of coronavirus disease 2019 (Covid-19). Tocilizumab, an IL-6 receptor blocking monoclonal antibody, has been repurposed for Covid-19, but prospective trials and dose-finding studies in Covid-19 are lacking. Methods We conducted a phase 2 trial of low-dose tocilizumab in hospitalized adult patients with Covid-19, radiographic pulmonary infiltrate, fever, and C-reactive protein (CRP) >= 40 mg/L who did not require mechanical ventilation. Dose cohorts were determined by a trial Operations Committee, stratified by CRP and epidemiologic risk factors. A range of doses from 40 to 200 mg (low-dose tocilizumab) was evaluated, with allowance for one repeat dose at 24-48 hours. The primary objective was to assess the relationship of dose to fever resolution and CRP response. Outcomes were compared with retrospective controls with Covid-19. Correlative studies evaluating host antibody response were performed in parallel. Findings A total of 32 patients received low-dose tocilizumab. This cohort had improved fever resolution (75.0% vs. 34.2%, p = 0.001) and CRP decline (86.2% vs. 14.3%, p < 0.001) in the 24-48 hours following drug administration, as compared to the retrospective controls (N=41). The probabilities of fever resolution or CRP decline did not appear to be dose-related in this small study (p=0.80 and p=0.10, respectively). Within the 28-day follow-up, 5 (15.6%) patients died. For patients who recovered, median time to clinical recovery was 3 days (IQR, 2-5). Clinically presumed and/or cultured bacterial superinfections were reported in 5 (15.6%) patients. Correlative biological studies demonstrated that tocilizumab-treated patients produced anti-SARS-CoV-2 antibodies comparable to controls. Interpretation Low-dose tocilizumab was associated with rapid improvement in clinical and laboratory measures of hyperinflammation in hospitalized patients with Covid-19. Results of this trial and its correlative biological studies provide rationale for a randomized, controlled trial of low-dose tocilizumab in Covid-19.

Universal molecular Clostridioides difficile screening and overtreatment in solid organ transplant recipients

BACKGROUND

Screening for Clostridioides difficile (CD) colonization can be performed using molecular testing to identify the presence of microbial DNA of the toxin gene. Colonization rates for hospitalized patients are as high as 20% and may be considerably higher in solid organ transplant (SOT) recipients. Treatment for CD should be based on clinical disease and not colonization, yet clinicians may misinterpret a positive CD screen resulting in overtreatment.

OBJECTIVES

The objective of this analysis is to determine how often positive CD screens resulted in inappropriate treatment with oral vancomycin.

METHODS

Clostridioides difficile screens were performed using the Xpert C difficile assay (Cepheid), a nucleic acid amplification testing method utilizing polymerase chain reaction (PCR), on peri-rectal swabs for newly admitted patients. This was a single-center cohort study of adult patients with CD screens hospitalized between July 2015 and November 2018. The primary outcome was the rate of inappropriate oral vancomycin treatment in all patients and in SOT recipients, defined as therapy in the absence of diarrhea.

RESULTS

Of the 47 076 total CD screens reviewed, 1,921 were positive. In the SOT cohort, 58 of 329 screens were positive (4.1% vs 17.9%, P < .01). Of all patients with a positive CD screen, 20.1% (386/1921) were treated with oral vancomycin within 48 hours of swab collection. In the SOT cohort, 39.6% (23/58) with positive CD screens were treated with oral vancomycin within 48 hours. Of the SOT patients who received oral vancomycin, 39% (9/23) did not have true CD infection.

CONCLUSION

Solid organ transplant recipients were more likely to have CD colonization detected by peri-rectal screening than the general inpatient population. SOT and non-SOT patients were treated with oral vancomycin at similar rates in response to the positive screen. Nearly half of the oral vancomycin use in SOT recipients was likely overtreatment, but this finding is limited by the low number of patients in this cohort.

Impact of mail order pharmacy use and travel time to pharmacy on viral suppression among people living with HIV

This study aimed to evaluate the impact of mail order pharmacy services and travel time to pharmacy on HIV viral suppression rates among people living with HIV. For adult patients receiving HIV care from 2010 to 2015 at an urban HIV care clinic, we collected demographics, pharmacy type, viral load, and patient home and pharmacy address. We geocoded addresses and measured travel time to pharmacy by car and public transportation. No difference was observed in recent viral suppression rates based on pharmacy type (p = 0.41), distance to pharmacy (p = 0.16), or travel time to pharmacy by car (p = 0.20) or public transportation (p = 0.15). The only factors significantly associated with sustained viral suppression were number of doses per day of antiretroviral therapy, with patients prescribed twice daily regimens less likely to be virally suppressed than those prescribed once daily regimens (aOR 0.4, 95% CI, [0.1, 0.6]) and average household income in patients' zip code, with patients living in zip codes with average household income <$40,000 per year less likely to be virally suppressed than those living in zip codes with average income >$55,000 per year (aOR 0.2. 95% CI, [0.1, 0.7]).

1039. Forty-eight-hour Antibiotic Time-out: Impact on Antibiotic Duration and Clinical Outcomes

Background

A core element of the Centers for Disease Control and Prevention Antimicrobial Stewardship standard for the inpatient setting includes a 48-hour antibiotic time-out (ATO) process to reassess antibiotic indication. We implemented an automated alert in the electronic health record (EHR) that identifies patients that have received >=48hours of antibiotic therapy. The alert requires the clinician (physician or pharmacist) to note an indication for continuation or plan for discontinuation. Within the alert, a dashboard was developed to include relevant patient information (e.g., temperature, white blood cell count, microbiology, etc). We sought to evaluate the impact of the ATO alert on the duration of therapy (DOT) of cefepime (CFP), ceftazidime (CTZ) and vancomycin (VAN), for the treatment of pneumonia (PNA) and urinary tract infections (UTI) for adult and pediatric patients.

Methods

This quasi-experimental, retrospective analysis included adult and pediatric patients that received ≥48 hours of CFP, CTZ, or VAN for UTI or PNA between April 1, 2017 and July 31, 2017 (pre-48H ATO) and October 1, 2018–December 31, 2018 (post-48H ATO). Fields at order-entry to specify an antibiotic indication were not available prior to our EHR interventions. A randomized subset from the Pre-48Hr ATO group was selected for detailed analysis. The primary endpoint was to evaluate the average DOT of CFP/CTZ combined, VAN alone, and the combination of CFP/CTZ/VAN. We also evaluated length of stay (LOS), all-cause inpatient mortality, and 30-day readmissions.

Results

A total of 157 antibiotic orders (n = 94 patients) were evaluated in the pre-48h ATO group, and 2093 antibiotic orders (n = 521 patients) post-48H ATO group. Pre-48H ATO, 85 patients received CFP/CTZ and 72 VAN. Post-48H ATO, 322 patients received CFP/CTZ and 198 VAN. PNA was the most common indication pre- and post-48H ATO. DOT significantly decreased pre- vs. post-48H ATO (Figure 1). LOS was 2 days shorter (P = 0.01) in the post-48H ATO group, mortality and 30-day readmissions was similar between groups (Table 1).

Conclusion

Average antibiotic DOT for CFP/CTZ, and VAN significantly decreased following the implementation of the 48H ATO at our medical center. LOS was reduced by 2 days, while mortality and 30-day readmissions were similar before and after.

Disclosures

All authors: No reported disclosures.

1003. Impact of a Standardized Pharmacist-led Β-lactam Allergy Interview on the Quality of Allergy Documentation

Background

Reported β-lactam allergies are common and are associated with inappropriate antibiotic therapy, poor clinical outcomes, and increased hospital costs. Documentation of β-lactam reactions is often incomplete and many patients with a reported allergy can tolerate a β-lactam antibiotic. This study aims to evaluate the impact of a standardized interviewing tool used by pharmacists on the quality of β-lactam allergy documentation.

Methods

This is a single-center, prospective, quasi-experimental study of adult inpatients. Patients were included if they had a documented β-lactam allergy, were interviewed by a pharmacist utilizing a standardized tool, and had the β-lactam allergy updated in the electronic medical record. The primary outcome was the percentage of patients with a complete allergy history documented. A complete allergy history was defined as including a description of the type of reaction, time of the reaction, and timing of the reaction. Secondary endpoints included the documentation of individual allergy history components, including if interventions were required to manage the reaction, tolerance of other β-lactams and receipt of penicillin skin testing in the past. A subgroup analysis was also performed among patients who received antibiotics during the admission evaluating antibiotic use, length of stay, mortality, and readmission.

Results

The study included 107 patients. The average time to complete an interview was 14.8 minutes. After the interview, 11 (10%) patients had the β-lactam allergy label removed. Consequently 107 allergy labels were evaluated in the pre-interview arm and 96 allergy labels in the post-interview arm. More patients had a documented complete allergy history after pharmacist intervention (39% vs. 0%, P &lt; 0.001). Documentation of all components of the allergy history improved after the interview (Table 1). Additionally, the amount of patients with an unknown reaction significantly declined (21% vs. 6%, P = 0.004).

Conclusion

The use of a standardized β-lactam allergy interview tool improved the quality of allergy documentation, led to de-labeling of β-lactam allergies, and reduced the amount of unknown reactions.

Disclosures

All authors: No reported disclosures.

1055. Addition of Antimicrobial Stewardship Program Weekend Coverage Increases Interventions while Reducing Antimicrobial Duration and Cost

Background

Expansion of Antimicrobial Stewardship Program (ASP) activities to include coverage of weekends has been shown to facilitate further optimization of antimicrobial usage. Beginning July 2018, we implemented full ASP coverage on weekends from 0700–1530 by infectious diseases (ID) clinical pharmacists and pharmacy residents. We sought to evaluate the impact of the addition of weekend ASP coverage on the number of interventions, antimicrobial duration and cost of target broad-spectrum antimicrobials.

Methods

Antimicrobials reviewed by ASP on a weekend day between July 14, 2018 and December 16, 2018 were included in the analysis. The primary outcome was the number and type of documented interventions associated with the antimicrobials reviewed. Secondary outcomes included the total duration of meropenem, daptomycin, and micafungin initiated on a weekend, estimated expenditures on these target broad-spectrum antimicrobials, and comparison of the average number of interventions performed per day by ID clinical pharmacists vs. pharmacy residents. For comparison, we also evaluated these secondary outcomes prior to ASP weekend coverage, between July 16, 2017 and December 9, 2017.

Results

A total of 688 antimicrobials were reviewed on weekend days during the included time-frame with 753 interventions (average number of interventions/day: 37). Table 1 summarizes the type of interventions. The acceptance rate for interventions was 99%. The average number of interventions per day for ID clinical pharmacists vs. pharmacy residents was 57.9 and 26.2, respectively. Table 2 shows the total duration of therapy (DOT) and total expenditures on target antimicrobials before and after ASP weekend coverage. The total DOT of target antimicrobials agents decreased from 21 days to 7 days, with an estimated 3,165 dollar decrease in expenditures during the included time-frame.

Conclusion

Expansion of ASP coverage to include weekends allowed us to provide 753 interventions over 4 months that would not otherwise have been made when no ASP coverage was available. This was associated with a reduction in broad-spectrum antimicrobial duration of therapy and expenditures when compared with weekends where ASP weekend coverage was not available.

Disclosures

All authors: No reported disclosures.

1996. Enteric Multiplex PCR Testing: Antimicrobial Stewardship Friend or Foe

Background

There are advantages and challenges associated with enteric multiplex PCR testing. Fast turnaround time can lead to prompt pathogen identification and antibiotic initiation, decreased length of stay and decreased time in isolation. Challenges include identification of multiple organisms, carrier state detection, and detection of organisms with uncertain pathogenic potential, which can lead to unnecessary antibiotic use.

Methods

Two institutions transitioned from stool culture to stool PCR testing for identification of diarrheal pathogens. On February 1, 2016, Center 1 employed the BioFire® FilmArray® GI Panel, which detects 22 organisms and includes targets of unclear clinical significance. Center 2 implemented the BD MAX™ Enteric Bacterial Panel on 3/6/2019, which reports 4 bacterial known pathogens. Fluoroquinolone (FQ) and third-generation cephalosporin (TGC) prescribing in response to positive PCR testing was assessed over a 1 month period. Antibiotics were counted when prescribed within 72 hours of the collection date.

Results

At Center 1, 332 GI PCR panels were ordered, 94 (28.3%) were positive and 15 (16%) were treated; 4 received an FQ (26%), and 11 (73%) received a TGC. Center 1 organisms included 44 Clostridioides difficile, 27 Norovirus, 8 Enteropathogenic E. coli, 7 Sapovirus, 4 Campylobacter species, 2 Giardia lamblia, 2 Rotavirus, 1 Shigella/Enteroinvasive E. coli and 1 Salmonella species. Of 642 PCR tests ordered at Center 2, 16 (2.5%) were positive and 11 (69%) were treated; 10 (91%) received a FQ, and 1 (9%) received a TGC. Center 2 organisms included 8 non-typhoidal Salmonella species, 5 Aeromonas species, 2 Shigella sonnei and 1 Salmonella typhi.

Conclusion

Implementation of an enteric multiplex PCR test with targets of uncertain clinical significance is more likely to yield an abnormal result than a PCR test with only known pathogens. However, careful interpretation of results can avoid unnecessary antimicrobial use. Antimicrobial stewardship teams should work in tandem with microbiology laboratories to implement enteric multiplex PCR tests and monitor the impact on antibiotic use. Larger studies are needed to definitively assess the impact of the GI panel on antimicrobial prescribing within the context of patient comorbidities and institutional practices.

Disclosures

All authors: No reported disclosures.

1549. Impact of New Fluoroquinolone Breakpoints on Enterobacteriaceae Susceptibility Rates and Clinical Outcomes

Background

In January 2019, the Clinical and Laboratory Standards Institute (CLSI) lowered the Fluoroquinolone (FQ) susceptibility breakpoints for Enterobacteriaceae. The new breakpoints were updated primarily based on FQ pharmacodynamics, and only limited clinical data. We sought to evaluate clinical outcomes among patients who received an FQ for infection with Enterobacteriaceae with MIC values that would now be considered resistant, using the new interpretive criteria. We also assessed the potential impact of the new breakpoints on overall blood and urine Enterobacteriaceae susceptibility rates at our medical center.

Methods

All positive blood and urine cultures with Enterobacteriaceae between September 1, 2018 and February 28, 2019 were included. Enterobacteriaceae isolates with ciprofloxacin MICs of 0.5 and 1 µg/mL (based on new breakpoints, now considered non-susceptible) were identified. We assessed the length of stay (LOS), mortality, and 30-day readmissions among patients who received an FQ for treatment. The impact of the new breakpoints on overall Enterobacteriaceae susceptibilities from urine and blood isolates was also determined.

Results

A total of 1,761 cultures (191 blood, 1,570 urine) grew Enterobacteriaceae. One-hundred and twenty-five (7%) cultures grew isolates with a ciprofloxacin MIC of 0.5 or 1 µg/mL. Eighteen patients with Enterobacteriaceae isolated (4 blood, 14 urine) received an FQ. Among these patients, the median LOS was 4 days; one patient was readmitted within 30 days, and 0% mortality was observed. The patient readmitted within 30 days received an FQ for a blood isolate with MIC 0.5. Overall, with the revised breakpoints, we observed a 4.2% decrease in the number of Enterobacteriaceae that would be susceptible to ciprofloxacin (Figure 1).

Conclusion

The new FQ breakpoints for Enterobacteriaceae will have a marginal impact on overall FQ susceptibility rates at our medical center. In this single-center study, patients that received FQ antibiotics for Enterobacteriaceae with MIC values now considered intermediate or resistant did not appear to experience poor outcomes.

Disclosures

All authors: No reported disclosures.

2258. Correlation of Electroencephalogram Findings and Dose Relative to Renal Function among Patients with Possible Cefepime-Induced Encephalopathy

Background

Cefepime-induced encephalopathy (CIE) is thought to be a rare toxicity, with an overall incidence of <1%. However, the low incidence may be a result of under-recognition and difficulty in identifying the exact etiology of encephalopathy in hospitalized patients. Among patients with suspected CIE, electroencephalograms (EEGs) sometimes show abnormal activity like triphasic waveforms (TPWs). We asked whether the incidence of EEG findings consistent with CIE varies with cefepime (CFP) dose relative to eGFR (dose/eGFR). We also compared the incidence of these EEG findings in patients receiving CFP to the incidence in patients receiving piperacillin–tazobactam (PT).

Methods

In a retrospective analysis, data between 8/1/2016 and 5/24/2018 were extracted from the University of Chicago Clinical Data Warehouse. Patients 20–79 years old who received PT or CFP were included; those requiring renal replacement therapy or who had eGFR <10 mL/minute/BSA at baseline were excluded. The average daily dose of PT or CFP was calculated to determine dose/eGFR. Linear or logistic regressions were performed in STATA.

Results

EEGs were obtained in 66 (4.3%) of 1525 patients receiving CFP and in 28 (3.3%) of 842 receiving PT. TPWs were present in 19 (28%) of EEGs from the CFP group, and in none of the EEGs from the PT group. Figure 1 shows the correlation between CFP dose/eGFR ratio and occurrence/severity of TPWs. Ordered logistic regression analysis identified a coefficient of 20.9 (95% CI; 3.7–38.2). Figure 2 shows only a weak association between CFP dose/eGFR and background frequency (BFS; R2 = 0.05). In the PT group, BFS was not correlated with PT dose/eGFR (R2 = 0.01).

Conclusion

TPWs were more likely to be found in patients receiving CFP than PT, suggesting that in the absence of other metabolic abnormalities, TPWs might be specific for CFP. Higher CFP dose-to-eGFR ratios predispose to and potentially worsen the severity of TPWs. Unlike TPWs, BFS was only weakly associated with CFP dose/eGFR and even less associated with PT dose/eGFR ratio.

Disclosures

All authors: No reported disclosures.

2669. Evaluation of Post-Operative Acute Kidney Injury with Piperacillin–Tazobactam Combined with Vancomycin for Lung Transplant Prophylaxis

Background

Several studies have identified that the addition of vancomycin (VAN) to piperacillin–tazobactam (PT) is associated with a higher incidence of nephrotoxicity when compared with other antibiotic regimens. Beginning in June 2017, our lung transplant antibiotic prophylaxis regimen was modified from PT monotherapy to VAN and PT.

Methods

All adult lung transplant patients between January 1, 2015 and November 10, 2018 were included. Patients were excluded if acute kidney injury (AKI) was present prior to transplant. Rates of AKI within 7 days of transplant were compared between those who received prophylaxis with PT and VAN vs. those receiving alternative regimens (AR). Patients receiving less than 1 dose of vancomycin or less than 3 doses PT (less than 24hours) were deemed to be in the alternative regimen group. AKI was defined as either an increase in serum creatinine (SCr) by ≥0.3 mg/dL within 48 hours or increase in SCr to ≥1.5 times baseline (within 7 days post-transplant). Secondary outcomes included duration of initial prophylactic antibiotic regimens, hospital length of stay (LOS), and all-cause inpatient mortality.

Results

Eighty-six patients were included, 44 (51%) patients received PT/VAN. Baseline characteristics and results shown in Table 1. Of those receiving PT/VAN for prophylaxis, 24 (54%) developed AKI within 7 days of transplant while 15 (36%) of 42 patients receiving AR developed AKI (P = 0.08).

Conclusion

A larger proportion of patients that received PT/VAN for transplant antibiotic prophylaxis experienced AKI within 7 days. Although the difference did not reach statistical significance, a 19% higher incidence of AKI warrants need for further investigation.

Disclosures

All authors: No reported disclosures.

Antimicrobial Stewardship Review of Automated Candidemia Alerts Using the Epic Stewardship Module Improves Bundle-of-Care Adherence

Background

Antimicrobial stewardship interventions utilizing real-time alerting through the electronic medical record enable timely implementation of the bundle of care (BOC) for patients with severe infections, such as candidemia. Automated alerting for candidemia using the Epic stewardship module has been in place since July 2015 at our medical center. We sought to assess the impact of these alerts.

Methods

All adult inpatients with candidemia between April 1, 2011, and March 31, 2012 (pre-intervention), and June 30, 2016, and July 1, 2017 (post-intervention), were evaluated for BOC adherence. We also evaluated the impact on timeliness to initiate targeted therapy, length of stay (LOS), and 30-day mortality.

Results

Eighty-four patients were included, 42 in the pre- and 42 in the post-intervention group. Adherence to BOC was significantly improved, from 48% (pre-intervention) to 83% (post-intervention; P = .001). The median time to initiation of therapy was 4.8 hours vs 3.3 hours (P = .58), the median LOS was 24 and 18 days (P = .28), and 30-day mortality was 19% and 26% (P = .60) in the pre- and post-intervention groups, respectively.

Conclusions

Antimicrobial stewardship program review of automated alerts identifying patients with candidemia resulted in significantly improved BOC adherence and was associated with a 1.5-hour reduction in time to initiation of antifungal therapy. No significant change was observed with 30-day mortality or LOS.

Moxifloxacin versus levofloxacin for antibacterial prophylaxis in acute leukemia patients

Objective

The primary endpoint of this study was to determine the incidence of febrile neutropenia among patients receiving either moxifloxacin or levofloxacin for antibacterial prophylaxis. Secondary endpoints were number of documented infections and in-hospital mortality in patients who develop febrile neutropenia.

Methods

A single-center retrospective cohort analysis at a large tertiary care academic medical center was conducted. This study included adult acute leukemia patients (age ≥18 years old) who received inpatient antibacterial prophylaxis (moxifloxacin or levofloxacin) from 1 July 2012 to 1 October 2014. Patients were excluded from the study if they were treated with antimicrobial therapy in the preceding five days or admitted to the hospital with neutropenic fever. Fisher’s exact test was used for categorical data and Mann–Whitney test for continuous data. Logistic regression analysis was used to determine risk factors for febrile neutropenia.

Results

Eighty-five patients were included in the final analysis with 40 patients who received moxifloxacin and 45 patients who received levofloxacin. Baseline characteristics were similar between the two groups. Twenty-two patients experienced febrile neutropenia requiring intravenous antibiotics in the moxifloxacin group and 30 patients in the levofloxacin group (P = 0.190). Age and duration of neutropenia appeared to predict for febrile neutropenia; however, after multivariate analysis, longer duration of neutropenia was shown to be the best predictor for febrile neutropenia with an odds ratio of 4.69 (95% CI, 1.697–12.968). Both groups had similar rates of documented infections and in-hospital morality.

Conclusion

Moxifloxacin and levofloxacin showed similar rates of febrile neutropenia when used for neutropenic antibacterial prophylaxis in acute leukemia patients.

Reducing medication errors involving antiretroviral therapy with targeted electronic medical record modifications

Medication errors are common among HIV-infected patients on anti-retroviral therapy (ART), especially when transitioning to the inpatient setting. In previous studies, medication error rates among hospitalized patients on ART have been reported to exceed 50%. When patients receiving ART are admitted to the hospital, medication errors can be prevented through optimization of administration instructions and dosing defaults in order-entry screens in the electronic medical record (EMR). We sought to evaluate the impact of EMR modifications (defaulted doses, frequencies, and administration instructions) implemented to improve the order-entry process and reduce errors. All adult patients admitted between 10/1/2010-3/31/2012 (pre-EMR modification) and 10/1/2013-3/31/2014 (post-EMR modification) that continued on ART upon admission were included. The primary outcome was the overall rate of medication errors identified through review by the antimicrobial stewardship program (ASP). We also characterized the types of medication errors identified during the two time periods. Following EMR modifications, the medication error rate identified through ASP review was reduced from 50.2% to 28.2% (P < 0.01). The number of medication related errors relating to dosage (regimens requiring dose optimization, renal dose adjustment, and dose timing) were reduced by 22% (P < 0.01). Modifications at the anti-retroviral medication order-entry screens in the EMR significantly reduced medication errors, particularly with respect to dosing and dose timing.

1904. Impact of Mail Order Pharmacy Use on Viral Suppression Among HIV-Infected Patients

Background

There are many barriers to adherence to antiretroviral medications, including pharmacy accessibility. Few studies have evaluated the impact of pharmacy distance or use of mail order pharmacy services on HIV viral load suppression relative to use of an “in-person” pharmacy. The purpose of our study was to determine whether there is a difference in viral suppression rates among patients who utilize mail order pharmacy services vs. an in-person pharmacy for filling antiretroviral prescriptions. Our study also looked at the effect of distance and travel time to viral suppression for patients who use in-person pharmacy services.

Methods

This was a single-center, retrospective cohort study of adult HIV-positive patients who received care between 2006 and 2015 at an urban HIV care clinic. We collected patient demographic information, ART regimen, home address, pharmacy address, and laboratory values. For patients who utilized retail pharmacies, patients’ home addresses and the location of the pharmacy were geocoded using ESRI’s StreetMap Premium geocoding service. We calculated patients’ travel distance to pharmacy and travel time to pharmacy along a street network in a private vehicle. Chi-squared tests and logistic regression were used to determine the association between in-person or mail order pharmacy services and distance to pharmacy and viral suppression (viral load ≤200 copies/mL).

Results

There were 214 patients in the mail order group and 214 patients included the in-person pharmacy group. Baseline characteristics were similar between the groups, with the exception of more people who inject drugs in the mail order group (6.1% vs. 1.8%, P = 0.05). No difference in viral load suppression was observed between groups (21.7% vs. 20.2%, P = 0.679). There was no difference in viral suppression depending on the distance (1.46 miles away in viral suppressed patients vs. 1.36 miles, P = 0.75) or travel time to pharmacy (7 minutes vs. 6.6 minutes, P = 0.75) for the in-person pharmacy group. Factors found to be significantly associated with suppressed viral loads were older age, white race, and higher CD4 counts.

Conclusion

Viral suppression was not associated with pharmacy type, distance to pharmacy, or travel time to pharmacy.

Disclosures

All authors: No reported disclosures.

Multicentre study of posaconazole delayed-release tablet serum level and association with hepatotoxicity and QTc prolongation

Objectives

The association of posaconazole serum concentrations and toxicity is unclear. An assessment of whether levels obtained with the delayed-release tablet (DRT) formulation are correlated with abnormal liver function test (LFT) results and/or QTc prolongation was undertaken.

Methods

This was a multicentre, retrospective, observational study of adult patients with cancer between 26 November 2013 and 14 November 2014. Patients were included if they received posaconazole DRT with a posaconazole level obtained between days 5 and 14. Clinical data, including demographics, hepatotoxic medications, posaconazole levels, LFTs and QTc intervals, were obtained. Association of factors with changes in LFTs and QTc prolongation was assessed using linear and logistic regression.

Results

One hundred and sixty-six study patients were included. The median posaconazole level was 1250 (range 110-4220) ng/mL and the median time until level was 6 (range 5-14) days. There was a statistically significant increase in AST ( P  <   0.001), ALT ( P  <   0.001), alkaline phosphatase (ALK) ( P  <   0.001), total bilirubin (TBILI) ( P  <   0.001) and QTc ( P  =   0.05) from baseline. Posaconazole levels were not associated with increases in AST [β (SE) = -0.33 (2.2), P  =   0.88], log ALT [β (SE) = -0.02 (0.03), P  =   0.63], ALK [β (SE) = 2.2 (2.9), P  =   0.46] and TBILI [β (SE) = -0.01 (0.04), P  =   0.88]. For each additional hepatotoxic medication, there was a mean change in TBILI of 0.13 mg/dL ( P  =   0.02) and ALK of 7.1 U/L ( P  =   0.09). No statistically significant association between posaconazole level and QTc interval prolongation was found.

Conclusions

We did not identify an association between posaconazole serum concentrations and LFT elevations or QTc prolongation. However, some LFTs were found to increase with more hepatotoxic medications administered.

Guideline compliance and clinical outcomes among patients with Staphylococcus aureus bacteremia with infectious diseases consultation in addition to antimicrobial stewardship-directed review

OBJECTIVE

Previous studies have shown infectious diseases consultation (IDC) for Staphylococcus aureus bacteremia (SAB) improves management and outcomes. The influence of IDC on outcomes for SAB in addition to an antimicrobial stewardship program (ASP) review for adult inpatients with SAB has not been evaluated. The purpose of this study was to investigate the effect of IDC on SAB management with concomitant ASP review and resulting outcomes.

METHODS

Adult inpatients with SAB admitted December 2012-October 2014 were included. The primary end point compared adherence to Infectious Disease Society of America guideline recommendations between patients receiving an IDC versus those not receiving an IDC. We also evaluated adherence to the individual components of the primary end point and clinical outcomes, including time to microbiologic clearance, recurrence of bacteremia, mortality, and length of stay.

RESULTS

This study included 154 patients (115 IDC and 39 non-IDC). Guideline adherence was significantly greater in the IDC group 78% versus 46% in the non-IDC group (P < .001). Significantly more patients in the IDC group had echocardiography (91% vs 67%; P < .001) and follow-up blood cultures (92% vs 64%; P > .001). Mortality was also greater in the non-IDC group (23%) versus 5% for the IDC group (P = .001).

CONCLUSIONS

Patients with SAB receiving an IDC were more likely to receive guideline-congruent management and had significantly reduced mortality. No improvements in antibiotic choice or dosing were observed, likely a result of ASP review.

Impact of Pharmacy Practice Model Expansion on Pharmacokinetic Services: Optimization of Vancomycin Dosing and Improved Patient Safety

Background: The impact of pharmacy interventions on optimizing vancomycin therapy has been described, however interventions vary among studies and the most optimal pharmacy practice model (PPM) for pharmacokinetic (PK) services has not been established. Objective: The purpose of this study is to demonstrate the value of 24 hours a day, 7 days a week (24/7) PK services. Methods: New PK services were implemented in 2 phases with institutional PPM expansion. Phase 1 included universal monitoring by pharmacists with recommendations made to prescribers during business hours. Phase 2 expanded clinical pharmacists' coverage to 24/7 and provided an optional 24/7 pharmacist-managed PK consult service. We compared vancomycin therapeutic trough attainment, dosing, and clinical and safety outcomes between phases 1 and 2 in adult inpatients receiving therapeutic intravenous vancomycin. Results. One hundred and fifty patients were included in each phase. Phase 2 had a greater proportion of vancomycin courses with therapeutic initial trough concentrations (27.5% vs 46.1%; p = 0.002), higher initial trough concentrations (10.9 mcg/mL vs 16.4 mcg/mL; p < 0.001), and optimized initial vancomycin dosing (13.5 mg/kg vs 16.2 mg/kg; p < 0.001). Phase 2 also saw significant reduction in the incidence of vancomycin-associated nephrotoxicity (21.1% vs 11.7%; p = 0.038). Dose optimization and improvement in initial target trough attainment were most notable among intensive care unit (ICU) patients. Conclusions. Our study demonstrated that 24/7 PK services implemented with institutional PPM expansion optimized vancomycin target trough attainment and improved patient safety.

Possible serotonin syndrome with carbidopa-levodopa and linezolid

WHAT IS KNOWN AND OBJECTIVE

Serotonin syndrome (SS) can occur when linezolid is combined with other serotonergic agents.

CASE DESCRIPTION

We report a case of possible SS in an elderly patient receiving linezolid in combination with carbidopa-levodopa (CL).

WHAT IS NEW AND CONCLUSION

Although certain classes of agents are commonly reported as causing SS among patients receiving linezolid, there are no specific case reports detailing this reaction with CL. Linezolid combined with CL should generally be avoided; however, if linezolid must be used, discontinuation of other agents with serotonergic activity is recommended with careful monitoring for signs and symptoms of SS.

Impact of the FDA Warning for Azithromycin and Risk for QT Prolongation on Utilization at an Academic Medical Center

A US Food and Drug Administration (FDA) drug safety communication was released in March 2013, warning prescribers of the risk of QT prolongation associated with azithromycin. Overall azithromycin utilization and adherence to an inpatient QTc monitoring guideline during 8-month time periods before and after the warning were assessed to evaluate the impact of this warning on inpatient azithromycin utilization and QTc monitoring. Fifty-five patients were included in the prewarning time period and 50 were included in the postwarning period. A significant reduction in utilization in days of therapy per 1,000 patient days was observed (31.2 prewarning vs 17.5 postwarning, p < .001) in these groups. No changes in QTc monitoring among patients receiving azithromycin were identified. FDA warnings of severe, life-threatening toxicities can have a profound impact on utilization and prescribing of medications, however they may not necessarily change monitoring practices.

Impact of a clinical pathway on appropriate empiric vancomycin use in cancer patients with febrile neutropenia

Objectives Febrile neutropenia management guidelines recommend the use of vancomycin as part of an empiric antimicrobial regimen when specific criteria are met. Often, vancomycin use among patients with febrile neutropenia is not indicated and may be over utilized for this indication. We sought to evaluate the impact of implementing a febrile neutropenia clinical pathway on empiric vancomycin use for febrile neutropenia and to identify predictors of vancomycin use when not indicated. Methods Adult febrile neutropenia patients who received initial therapy with an anti-pseudomonal beta-lactam with or without vancomycin were identified before (June 2008 to November 2010) and after (June 2012 to June 2013) pathway implementation. Patients were assessed for appropriateness of therapy based on whether the patient received vancomycin consistent with guideline recommendations. Using a comorbidity index used for risk assessment in high risk hematology/oncology patients, we evaluated whether specific comorbidities are associated with inappropriate vancomycin use in the setting of febrile neutropenia. Results A total of 206 patients were included in the pre-pathway time period with 35.9% of patients receiving vancomycin therapy that was inconsistent with the pathway. A total of 131 patients were included in the post-pathway time period with 11.4% of patients receiving vancomycin inconsistent with the pathway ( p = 0.001). None of the comorbidities assessed, nor the comorbidity index score were found to be predictors of vancomycin use inconsistent with guideline recommendations. Conclusion Our study has demonstrated that implementation of a febrile neutropenia pathway can significantly improve adherence to national guideline recommendations with respect to empiric vancomycin utilization for febrile neutropenia.

Residency application screening tools: A survey of academic medical centers

PURPOSE

The current use and content of screening tools utilized by ASHP-accredited pharmacy residency programs were assessed.

METHODS

A survey consisting of 19 questions assessing residency programs and the screening of pharmacy residency program applicants was e-mailed to residency directors of 362 pharmacy residency programs at 105 University HealthSystem Consortium (UHC)-member institutions. Questions gathered general program demographic information, data related to applicant growth from residency years 2010-11 to 2011-12, and information about the residency screening processes currently used.

RESULTS

Responses were received from 73 residency program sites (69.5%) of the 105 UHC-member institutions to whom the e-mail was sent. Many sites used screening tools to calculate applicants' scores and then determined which candidates to invite for an onsite interview based on applicants' scores and group discussion. Seventy-eight percent (n = 57) of the 73 responding institutions reported the use of a screening tool or rubric to select applicants to invite for onsite interviews. The most common method of evaluation was individual applicant review before meeting as a group to discuss candidate selection. The most important factor for determining which residency candidate to interview was the overall impression based on the candidate's curriculum vitae (CV) and letters of recommendation.

CONCLUSION

Most residency programs in UHC-member hospitals used a screening tool to determine which applicants to invite for an onsite interview. The most important factor for determining which residency candidate to interview was the overall impression based on the candidate's CV and letters of recommendation.

Risk factors for systemic vancomycin exposure following administration of oral vancomycin for the treatment of Clostridium difficile infection

OBJECTIVE

To identify risk factors for systemic exposure to vancomycin (VAN) following administration of oral vancomycin (POV) for the treatment of Clostridium difficile infection (CDI).

DESIGN

Prospective, observational, single-center case series.

SETTING

Academic medical center.

PATIENTS

Hospitalized patients with suspected or confirmed CDI who received POV for at least 5 days.

INTERVENTION

Random VAN serum levels were obtained on days 5, 10, and weekly thereafter in patients treated for ≥ 5 days with POV without concomitant intravenous VAN.

MEASUREMENTS AND RESULTS

Of 117 random VAN serum levels from 85 patients, 58 patients (68.2%) had one or more detectable (≥ 0.05 μg/ml) levels and 15 (17.6%) of 85 patients had one or more levels > 2.5 μg/ml. Risk factors for detectable VAN exposure following administration of POV included POV dosages > 500 mg/day (odds ratio [OR] 35.83, 95% confidence interval [CI] 7.56-169.8), the presence of severe CDI (OR 4.11, 95% CI 2.76-10.83, p=0.028), intensive care unit (ICU) admission (OR 3.80, 95% CI 1.02-14.21, p=0.032), and the administration of POV ≥ 10 days (OR 6.71, 95% CI 1.81-24.83, p=0.0025). Risk factors for exposure to serum VAN concentrations > 2.5 μg/ml included the presence of gastrointestinal (GI) pathology (OR 5.22, 95% CI 3.45-18.3, p=0.031), ICU admission (OR 3.21, 95% CI 1.40-10.28, p=0.022), the use of VAN retention enemas (OR 4.73, 95% CI 2.42-20.39, p=0.036), and having a creatinine clearance ≤ 50 ml/minute or undergoing hemodialysis or continuous renal replacement therapy (OR 4.03, 95% CI 1.26-12.84, p=0.039).

CONCLUSIONS

Serum VAN levels were detected in 58 (68.2%) of 85 patients receiving POV for CDI. Risk factors for systemic exposure to VAN following administration of POV included ICU admission; VAN dosages > 500 mg/day; administration ≥ 10 days or as retention enemas; and the presence of severe CDI, renal dysfunction, or inflammatory conditions of the GI tract. Unique to our study, we identified ICU admission and the concomitant use of VAN retention enemas to be significant risk factors for systemic exposure to VAN.

Isavuconazole

Objective: To review the pharmacology, chemistry, in vitro susceptibility, pharmacokinetics, clinical efficacy, safety, tolerability, dosage, and administration of isavuconazole, a triazole antifungal agent. Data Sources: Studies and reviews were identified through an English language MEDLINE search (1978 to March 2015) and from http://www.clinicaltrials.gov , Food and Drug Administration (FDA) briefing documents, program abstracts from international symposia, and the manufacturer’s Web site. Study Selection and Data Extraction: All published and unpublished trials, abstracts, in vitro and preclinical studies, and FDA briefing documents were reviewed. Data Synthesis: Isavuconazole has activity against a number of clinically important yeasts and molds, including Candida spp, Aspergillus spp, Cryptococcus neoformans, and Trichosporon spp and variable activity against the Mucorales. Isavuconazole, available for both oral and intravenous administration, is characterized by slow elimination allowing once-daily dosing, extensive tissue distribution, and high (>99%) protein binding. The most commonly reported adverse events, which are mild and limited in nature, include nausea, diarrhea, and elevated liver function tests. Its drug interaction potential appears to be similar to other azole antifungals but less than those observed with voriconazole. Comparative trials are under way or have been recently completed for the treatment of candidemia, invasive candidiasis and aspergillosis, and rare mold infections. Conclusions: Isavuconazole has a broad spectrum of activity and favorable pharmacokinetic properties, providing an advantage over other currently available broad-spectrum azole antifungals and a clinically useful alternative to voriconazole for the treatment of invasive aspergillosis. It may also prove useful for the treatment of candidemia and invasive mold infections; however, these indications await the results of clinical trials.