Introduction: Daptomycin (DAP) is a cyclic lipopeptide that exhibits potent in vitro activity against many drug-resistant gram-positive organisms, including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). Despite substantial reports evaluating the clinical outcomes of DAP within the adult population, real-world data are lacking in children. The primary goal of this evaluation was to describe the clinical characteristics and outcomes of DAP use in pediatric patients across a wide range of infections. Methods: This retrospective evaluation included patients < 18 years of age who were treated with DAP from January 2014 to May 2023. The primary objective was to evaluate the composite clinical success, which was defined as a 30-day survival, the lack of a 30-day microbiological recurrence, and the resolution of signs and symptoms of an acute infection without therapy modifications based on clinical failures. Secondary objectives included adverse effects potentially attributable to DAP and reasons for DAP utilization. Results: Forty patients were included, which were predominately male (62.5%) and white (52.5%), with a median age of 8.7 [IQR, 4.4–16.0] years. DAP was used for a wide range of infections, including central line-associated bloodstream infections (CLABSIs; 32.5%), infective endocarditis (15.0%), surgical-site infections (12.5%), and osteomyelitis (12.5%). The most common pathogen isolated was MRSA (37.5%), and most patients were bacteremic (60.0%). The median DAP dose was 8 [IQR, 6–10] mg/kg, and the median duration of the DAP therapy was 11.5 [IQR, 4.8–18.8] days. Most patients achieved composite clinical success (75.0%). An adverse effect occurred in 5.0% of the patients. DAP was prescribed the most for its ease of use/ability to facilitate discharge (40.0%) and/or for issues with alternative therapies (37.5%). Conclusion: Most pediatric patients that received DAP demonstrated clinical success with a low incidence of adverse effects. Larger, real-world studies of DAP use are necessary to further assess clinical outcomes.

Background: Antimicrobial stewardship programs (ASPs) aim to optimize antimicrobial use through coordinated interventions that improve patient outcomes and reduce adverse events. While guidance exists from organizations including the Centers for Disease Control and Prevention and the Infectious Diseases Society of America, recommendations on effort allocation, working hours, and initiatives remain unclear. Methods: This cross-sectional survey assessed the institutional structure, effort allocation, initiatives, and on-call participation of adult ASPs in the United States from September to October 2024. The survey was distributed via email to several ASP-related listservs. Respondents indicating on-call participation were also inquired about working hours, initiatives performed, participants, and compensation. Results: Of 69 responses, most were from academic medical centers (59%) or community hospitals (35%), with 65% covering >500 beds. ASPs were often system-wide (78%) and primarily funded by their respective departments of pharmacy (87%). Common initiatives performed by all ASPs include answering ASP/infectious diseases questions, therapy de-escalation, and prospective audit and feedback. Twenty-four (69%) respondents indicated having an on-call model, with said programs reporting higher median inpatient full-time equivalents (FTEs) for physicians (0.5 vs 0.25) and pharmacists (2.9 vs 1.45) than those without. Commonly performed after-hours initiatives include preauthorization and answering microbiology inquiries. On-call coverage was generally performed during weekend daytimes and holidays, most often by pharmacists. Conclusions: This survey highlights differences in structure, effort allocation, and initiatives of ASPs based on on-call participation. Institutions participating in on-call reported higher FTE assignments for physicians and pharmacists and were more likely to perform time-sensitive initiatives.

Background: Compared to soybean oil intravenous fat emulsion (SO-IFE), use of mixed-oil IFE (MO-IFE) is associated with reduced rates of catheter-related bloodstream infections caused by coagulase-negative Staphylococcus species (CoNS) in pediatric patients receiving parenteral nutrition. Methods: Using an in vitro biofilm model, this study aimed to assess the impact of IFEs on biofilm formation among Staphylococcus species. S. aureus, S. capitis, S. epidermidis, S. haemolyticus, S. hominis, and S. lugdunensis were cultivated as biofilms in media supplemented with SO-IFE, MO-IFE, or fish oil IFE (IFE). Biomass was quantified by the crystal violet method, and follow-up planktonic growth assays assessed antimicrobial effects of IFEs. Results: Compared to SO-IFE, MO-IFE and FO-IFE significantly inhibited biofilm formation of S. aureus but did not impact planktonic growth. Contrary to clinical data, CoNS biofilm formation was not impacted by any of the IFEs tested. S. aureus biofilm inhibition in IFEs was further investigated by comparing differences following growth in SO-IFE supplemented with capric acid, docosahexaenoic acid (DHA), or eicosapenaenoic acid (EPA) to concentrations matching those of MO-IFE. Capric acid supplementation was associated with significant reduction in biofilm formation compared to SO-IFE alone. However, this was attributed to a bactericidal effect based on follow-up planktonic growth assays. Conclusions: These results suggest that biofilm formation in S. aureus is variably impacted by fatty acid composition in clinically relevant IFEs, with capric acid exhibiting bactericidal activity against tested isolates.

Background: Enterobacterales considered at risk of inducible AmpC production are denoted by mnemonics including SPACE and HECK-Yes! However, these mnemonics may fail to account for the variability in AmpC induction potential, which lends to variation in antibiotics chosen for management of associated infections and susceptibility reporting. This study aimed to evaluate clinical and microbiologic practice patterns for the management of infections caused by Enterobacterales at risk of inducible AmpC production. Methods: This cross-sectional survey was developed by a multidisciplinary infectious diseases (ID) team and distributed via ID-related listservs (November-December 2024). The survey assessed institutional demographics, β-lactam of choice, and microbiologic reporting for Enterobacterales with a moderate risk (Enterobacter cloacae complex, Klebsiella aerogenes, Citrobacter freundii) and low risk (Serratia marcescens, Morganella morganii, Providencia spp.) of inducible AmpC production. Results: Of 94 complete responses, most were from pharmacists (58.5%) and physicians (38.3%) working in adult academic medical centres (39.4%) or community hospitals (37.2%). Cefepime was the preferred β-lactam for invasive (87.2%) and non-invasive (68.1%) infections caused by moderate-risk inducible AmpC producers, while ceftriaxone was preferred for invasive (57.4%) and non-invasive (60.7%) infections caused by low-risk inducible AmpC Inducers. Cefepime (98.8% versus 98.8%), meropenem (85.5% versus 83.1%), piperacillin/tazobactam (72.3% versus 83.1%), and ceftriaxone (67.5% versus 94.0%) were commonly reported antibiotics on non-urinary antibiograms for moderate risk and low risk Enterobacterales, respectively. The beta-lactams reported in institutional antibiograms and microbiology susceptibility reporting were generally similar. Conclusions: This survey highlights differences in practice patterns for management of infections caused by inducible AmpC-producing Enterobacterales. These results emphasize the importance of standardized, evidence-based antimicrobial stewardship approaches and continued clinical investigation to better optimize therapy for infections caused by Enterobacterales capable of inducible AmpC production.

Background/Objectives: Ceftaroline (CPT) is a broad-spectrum, fifth-generation cephalosporin with in vitro activity against methicillin-resistant Staphylococcus aureus (MRSA) and drug-resistant Streptococcus pneumoniae. Real-world data on its use in pediatric patients remain limited. This study aimed to the describe clinical characteristics and outcomes associated with CPT use in pediatric patients at a pediatric academic medical center. Methods: This retrospective case series evaluated patients under 18 years of age who received CPT between November 2016 and August 2023. The primary outcome was clinical success, defined as a composite of 30-day survival, absence of microbiological recurrence within 30 days, and/or resolution of acute infection signs and symptoms without therapy modification due to clinical failure. The secondary outcomes included adverse effects potentially attributable to CPT and the clinical rationale guiding its use. Results: Among 25 patients, most were male (68%) with a median (IQR) age of 3.4 (1.4–14.3) years. The indications for use commonly included respiratory infections (48%), bacteremia (16%), and/or skin and soft tissue (12%) infections. The frequently used dosing regimens included 12 mg/kg (36%) and 8 mg/kg (28%) q8hr, with a median (IQR) duration of therapy of 4.6 (1.7–10.0) days. Clinical success was achieved in 96% of patients. No adverse effects attributable to CPT were observed and CPT was commonly used for escalation (40%) and/or issues with alternative therapies (36%). Conclusions: CPT use was associated with high clinical success rates and no observed adverse effects in this pediatric report. These findings support its use as a therapeutic option when the alternatives are limited. Larger multicenter studies are needed to further evaluate the clinical outcomes and safety of CPT use in pediatric patients.