Stevens, Ryan W.

AbstractBeta‐lactam therapeutic drug monitoring (TDM) can improve precision dosing and clinical outcomes in critically ill patients, but has not been implemented widely in the United States. Mayo Clinic recently implemented a beta‐lactam TDM program. This single‐center experience forms the basis of the manuscript which outlines practical considerations involved with beta‐lactam TDM implementation, including the pharmacist's role as a leader. Our implementation effort focused on three primary domains. First, we aimed to ensure a supportive organizational infrastructure. Early leadership engagement by the pharmacist‐led core team facilitated advocacy for the clinical need, allocation of resources, and assay development. Second, core clinical workflows were developed that addressed the preferred patient population for use, desirable pharmacokinetic and pharmacodynamic targets, and the preferred sampling strategy. Clinical tools to guide pharmacists in interpreting the results (e.g., pharmacokinetics calculator) and documenting decisions were developed. Third, stakeholders were offered repeated exposure to evidence and expertise to facilitate understanding and application of the new practice. This act of ‘individual internalization’ seems to be uniquely important to beta‐lactam TDM implementation compared with the implementation of other antimicrobial TDM programs. Educational strategies and supportive materials that were developed were focused on providing substantive and varied information tailored to the stakeholders' role in the process. For pharmacists, this included both clinical and operational considerations. A continuous improvement plan to support management of the process was instituted to address necessary updates and changes that inevitably emerged. In summary, the described approach to implementation of a pharmacist‐led beta‐lactam TDM program could be used as a roadmap to aid other institutions that aim to develop such a program.

Beta-hemolytic streptococci are common causes of bloodstream infection (BSI). There is emerging data regarding oral antibiotics for BSI but limited for beta-hemolytic streptococcal BSI.

Infective endocarditis (IE) is a rare but increasingly prevalent disease with high morbidity and mortality, requiring antimicrobials and at times surgical intervention. Through the decades of healthcare professionals’ experience with managing IE, certain dogmas and uncertainties have arisen around its pharmacotherapy. The introduction of new antimicrobials and novel combinations are exciting developments but also further complicate IE treatment choices. In this review, we provide and evaluate the relevant evidence focused around contemporary debates in IE treatment pharmacotherapy, including beta-lactam choice in MSSA IE, combination therapies (aminoglycosides, ceftaroline), the use of oral antimicrobials, the role of rifamycins, and long-acting lipoglycopeptides.

Abstract Days of therapy (DOT) currently serve as the standard antimicrobial utilization metric. However, by assigning the same weight to each agent rather than accounting for differences in spectrum of activity, DOT ignore key differences between agents that are fundamental to infectious diseases and critical to antimicrobial stewardship. Spectrum scoring assigns numeric values to individual antibiotic agents to quantify their spectrum of activity, allowing for the normalization of antibiotic utilization data. When used in conjunction with traditional metrics, spectrum scores may offer further clarity to antibiotic utilization; however, issues related to development, application, and standardization of spectrum scores remain. Despite these challenges, the potential applications of spectrum scores are vast. Here, we summarize existing data and explore the future of spectrum scoring, including application to both data analysis and routine patient care, use in inpatient and outpatient settings, integration within the electronic medical record, and opportunities for future research.

Antistaphylococcal penicillins (ASP) and cefazolin are first-line treatment of methicillin-susceptible Staphylococcus aureus (MSSA) bacteremia. Borderline oxacillin resistance (i.e., oxacillin MICs 1-8 μg/mL) is observed in strains hyperproducing beta-lactamases.

Leptotrichia species are anaerobic, Gram-negative bacilli increasingly recognized as pathogens capable of causing invasive infections such as bloodstream infection (BSI), particularly among immunocompromised patients. However, there is a paucity of data regarding epidemiology, antimicrobial susceptibility, optimal treatment, and clinical outcomes among patients with Leptotrichia bacteremia.

AbstractBackgroundItraconazole is the recommended first‐line treatment for mild‐to‐moderate blastomycosis and consolidation treatment of moderate‐to‐severe disease. Itraconazole is metabolised into three metabolites, including an active metabolite hydroxy‐itraconazole. Literature provides little evidence indicating whether therapeutic drug monitoring targets should be based on itraconazole parent compound alone or a sum of itraconazole and hydroxy‐itraconazole serum concentrations.ObjectivesThis study aims to compare clinical outcomes and adverse drug events (ADEs) of combined itraconazole and hydroxy‐itraconazole concentrations versus itraconazole parent compound alone in patients with blastomycosis.Patients/MethodsThis study was a retrospective cohort review of patients ≥18 years with probable or proven Blastomyces infection who received itraconazole with at least one documented serum itraconazole concentration. The primary outcome was rate of partial or complete treatment response across three patient groups: (1) Itraconazole parent compound >1.0 mcg/ml (parent), (2) parent compound <1.0 mcg/ml, but a combined itraconazole and hydroxy‐itraconazole >1.0 mcg/ml (combined) and (3) failure to achieve a combined or parent concentration >1.0 mcg/ml (subtherapeutic) for >75% of the duration of itraconazole therapy.ResultsA total of 80 patients were included (parent = 32, combined = 36, subtherapeutic = 12). No statistically significant difference was observed for rate of partial or complete treatment response (97% parent vs 94% combined, p = .99). Significantly higher mortality due to blastomycosis was observed in patients in the subtherapeutic group (0% parent vs 3% combined vs 25% subtherapeutic, p = .01).ConclusionsThis study supports an itraconazole therapeutic target combining itraconazole and hydroxy‐itraconazole >1.0 mcg/ml for blastomycosis treatment.

Abstract Background Leptotrichia spp. are anaerobic, gram-negative bacilli that are part of the normal oral and intestinal microbiota. Although traditionally considered non-pathogenic, these bacteria can result in invasive infections including bacteremia in immunosuppressed patients, particularly those with neutropenia. There are limited published data to inform best management strategies in those with Leptotrichia bacteremia. Methods All cases of Leptotrichia spp. bacteremia between January 2012 and 2022 at our tertiary academic medical center were retrospectively reviewed to determine patient risk factors, clinical outcomes, and antimicrobial susceptibilities. Descriptive statistical methods were used. Antimicrobial susceptibilities were performed by agar dilution. Results 26 cases of Leptotrichia spp. bacteremia were identified (Figure 1). The mean patient age was 55 years (SD 17), with 9 female patients (35%). All 26 patients were immunocompromised, predominantly due to hematologic malignancy (69%) or hematopoietic stem cell transplant (23%) (HSCT). 25 of 26 patients were actively neutropenic, with a median duration of neutropenia of 21 days (13-26) (Table 1). The most frequent sources of Leptotrichia bacteremia were gastrointestinal translocation (60%), followed by catheter-related infection (35%). 10 patients had polymicrobial bacteremia (38.5%). The primary antibiotics utilized to treat Leptotrichia bacteremia included metronidazole (42%), piperacillin-tazobactam (27%), and carbapenems (19%). Overall, the mean duration of treatment was 11 days, with a 60-day all-cause mortality of 19% (Table 1) with no cases of microbiologic relapse. In the 22 clinical isolates evaluated for susceptibility, Leptotrichia spp. were largely susceptible to metronidazole, penicillin, ertapenem, and piperacillin-tazobactam, but uniformly resistant to moxifloxacin (Table 2). Figure 1:Leptotrichia spp. identified as cause of bacteremia in 26 patientsTable 1:Baseline characteristics of patients with Leptotrichia bacteremia (n=26) between January 2012 to January 2022Table 2:Antimicrobial susceptibility profile of the Leptotrichia spp. (n=22) Conclusion Leptotrichia spp. may be a rare cause of bacteremia in neutropenic hosts, particularly those with underlying hematologic malignancies and HSCT. The pathogen has a favorable susceptibility profile to penicillins and carbapenems, but has high degree of resistance to fluoroquinolones. Disclosures All Authors: No reported disclosures.

Abstract Background URIs are the most common indication for outpatient antibiotic prescribing. Given high rates of unnecessary prescribing, these indications have been identified as a high-priority target for outpatient antimicrobial stewardship programs (ASP). Our primary objective was to evaluate the impact of a system-wide, multifaceted, outpatient ASP intervention bundle on unnecessary antibiotic prescribing for URI. Methods This quasi-experimental study was conducted from 2019 to 2021. ICD-10 codes for URIs were grouped into 3 tiers (i.e., tier I = antibiotics always indicated, tier II = sometimes, tier III = never). Encounters from 5 care specialties (i.e., family medicine, community internal medicine, express care, pediatrics, and emergency department) with a tier III URI primary ICD-10 code but without a secondary tier I or tier II code were included. COVID-19 ICD-10 codes were excluded. Interventions included construction of a prescribing data model, dissemination of clinician prescribing data and education, promotion of symptom management strategies, a patient-facing commitment poster, and a pre-populated URI order panel. Tools were designed at a system level and implemented by regional champions beginning in the 3rd quarter of 2020. The primary outcome was the rate of antibiotic prescribing, and the secondary outcome and counterbalance measure was the rate of repeat URI-related healthcare contact within 14 days. Outcomes were analyzed with chi-square with an α level of 0.05. Results A total of 147403 encounters were included. The overall antibiotic prescribing rate decreased from 24.1% to 12.3% between 2019 and 2021 (p&lt; 0.01). Significant reductions in tier III antibiotic prescribing were demonstrated for each region, care specialty, and syndrome evaluated (Table 1). A reduction in repeat healthcare contact was seen across the total cohort (9.5% in 2019 vs. 8.3% in 2021, p&lt; 0.01); decreases in repeat contact rates were observed in those not initially receiving an antibiotic (10.3% vs. 8.6%, p&lt; 0.01), but not in those who initially received an antibiotic (6.8% vs. 6.8%, p = 0.94). Tier III URI encounter level antimicrobial prescribing rates by region, care specialty, and syndrome Conclusion A multifaceted, outpatient ASP intervention bundle decreased rates of unnecessary antimicrobial prescribing without increasing rates of 14-day repeat URI-related healthcare contact. Disclosures Paschalis Vergidis, MD, AbbVie: DSMB|Cidara: Grant/Research Support|Scynexis: Grant/Research Support Evan Draper, PharmD, Gilead Foundation: Grant/Research Support Sara Ausman, PharmD, Gilead: Honoraria Christina G. Rivera, PharmD, Gilead: Grant/Research Support|Gilead: Honoraria|Insmed: Honoraria.