Executive Summary: State-of-the-Art Review: Fostering Collaborative Teamwork-A Comprehensive Approach to Vascular Graft Infection Following Arterial Reconstructive Surgery.

Vascular graft infection (VGI) is one of the most serious complications following arterial reconstructive surgery. VGI has received increasing attention over the past decade, but many questions remain regarding its diagnosis and management. In this review, we describe our approach to VGI through multidisciplinary collaboration and discuss decision-making for challenging presentations. This document will concentrate on VGI that impacts both aneurysms and pseudoaneurysms excluding the ascending thoracic aorta.

Fostering Collaborative Teamwork-A Comprehensive Approach to Vascular Graft Infection Following Arterial Reconstructive Surgery.

Vascular graft infection (VGI) is one of the most serious complications following arterial reconstructive surgery. VGI has received increasing attention over the past decade, but many questions remain regarding its diagnosis and management. In this review, we describe our approach to VGI through multidisciplinary collaboration and discuss decision making for challenging presentations. This review will concentrate on VGI that impacts both aneurysms and pseudoaneurysms excluding the ascending thoracic aorta.

Sequential Time to Positivity as a Prognostic Indicator in Staphylococcus aureus Bacteremia.

Background: We aimed to determine the factors associated with sequential blood culture time to positivity (STTP) and validate the previously defined time to positivity (TTP) ratio threshold of 1.5 in predicting adverse disease outcomes and mortality of Staphylococcus aureus bacteremia (SAB). Methods: We conducted an observational study of adult patients with SAB. The TTP ratio was calculated by dividing the TTP of the second blood culture by that of the first. Results: Of 186 patients, 69 (37%) were female, with a mean age of 63.6 years. Median TTP was 12 hours (interquartile range [IQR], 10-15 hours) from the initial and 21 hours (17-29) from sequential blood cultures. Methicillin-resistant S aureus (MRSA)-infected patients had significantly shorter STTPs (P < .001) and lower TTP ratios (P < .001) compared to patients with methicillin-susceptible S aureus (MSSA). A significant correlation between initial and STTP was observed in patients with MRSA (r = 0.42, P = .002) but not in those with MSSA. A higher rate of native valve endocarditis (NVE) significantly correlated with a TTP ratio of ≤1.5 (odds ratio, 2.65 [95% confidence interval, 1.3-5.6]; P = .01). The subgroup having an initial TTP <12 hours combined with a TTP ratio ≤1.5 showed the highest prevalence of NVE. Conclusions: The STTP varies based on methicillin susceptibility of S aureus isolate. This study suggests a potential clinical utility of the STTP to identify patients at a higher risk of NVE. However, prospective studies are required to validate these findings.

An inconspicuous identification: Isolation and identification of a novel Pichia species presenting as fungemia following cardiac surgery.

Fungemia is common in critically ill patient populations, and is associated with a high rate of mortality, especially when caused by nonalbicans Candida species. Herein, we describe a fatal case of fungemia following cardiothoracic surgery in which the organism, initially identified as Candida inconspicua, represents a novel species: Pichia alaskaensis.

Correction: Adema et al. Heartbreaking Decisions: The Dogma and Uncertainties of Antimicrobial Therapy in Infective Endocarditis. Pathogens 2023, 12, 703.

There was an error in the original publication [...].

Rhodococcus infection: a 10-year retrospective analysis of clinical experience and antimicrobial susceptibility profile.

Rhodococcus equi is an opportunistic pathogen known to cause pulmonary and extrapulmonary disease among immunocompromised patients. Treatment is frequently challenging due to intrinsic resistance to multiple antibiotic classes. While non-equi Rhodococcus spp. are prevalent, their clinical significance is poorly defined. There is also limited data on antibiotic susceptibility testing (AST) of Rhodococcus infection in humans. We conducted a single-center, retrospective cohort study evaluating clinical characteristics, microbiologic profile, and AST of Rhodococcus infections between June 2012 and 2022 at our tertiary academic medical center. Identification of Rhodococcus spp. was performed by Sanger 16S rRNA gene sequencing and/or matrix-assisted laser desorption ionization-time of flight mass spectrometry, and AST was performed by agar dilution. Three hundred twenty-two isolates of Rhodococcus spp. were identified from blood (50%), pulmonary (26%), and bone/joint (12%) sources. R. equi/hoagii, R. corynebacterioides, and R. erythropolis were the most frequently isolated species, with 19% of isolates identified only to genus level. One hundred ninety-nine isolates evaluated for AST demonstrated high-level resistance to amoxicillin/clavulanate, cephalosporins, and aminoglycosides. More than 95% susceptibility to imipenem, vancomycin, linezolid, rifampin, and clarithromycin was observed. Non-equi species showed a significantly more favorable AST profile relative to R. equi. Clinically significant Rhodococcus infection was rare with 10 cases diagnosed (majority due to R. equi) and managed. The majority of patients received 2- or 3-drug combination therapy for 2-6 months, with favorable clinical response. Significant differences in AST were observed between R. equi and non-equi species. Despite high antimicrobial resistance to several antibiotic classes, imipenem and vancomycin remain appropriate empiric treatment options for R. equi. Future research evaluating mechanisms underlying antimicrobial resistance is warranted.

Antimicrobial susceptibilities of Campylobacter fetus: report from a reference laboratory.

Campylobacter fetus is known to cause human disease, particularly in elderly and immunocompromised hosts. There are limited published data for antimicrobial susceptibility patterns with this organism, and no interpretive criteria are available. We reviewed antimicrobial susceptibilities of C. fetus isolates tested at a tertiary care center and reference laboratory over an 11-year period. C. fetus isolates from patients treated at Mayo Clinic and those sent as referrals for identification and susceptibility were included. Antimicrobial susceptibility testing was performed using agar dilution for ciprofloxacin, doxycycline, erythromycin, gentamicin, meropenem, and tetracycline. Geographic distribution, culture source, organism minimal inhibitory concentration (MIC) distributions, and MIC50 and MIC90 were examined. Excluding duplicates, 105 unique isolates were identified from 110 positive cultures. Blood cultures represented the most common source, followed by body fluids, skin and soft tissue, and central nervous system. Gentamicin and meropenem had favorable MIC50 and MIC90 of 1 µg/mL. Ciprofloxacin demonstrated an MIC50 of 1 µg/mL; however, the MIC90 was >2 µg/mL. Erythromycin demonstrated MIC50 and MIC90 of 2 µg/mL. Tetracycline and doxycycline were tested on a limited number of isolates and showed a wide range of MICs. Gentamicin and meropenem demonstrated favorable MICs in C. fetus isolates. These may represent therapeutic options for consideration in serious C. fetus infections, pending susceptibility results. Ciprofloxacin, which showed variable results, may be more appropriate for use only after susceptibility testing. C. fetus interpretive criteria are needed to aid clinicians in selection of both empiric and definitive therapies. IMPORTANCE: Our findings contribute to the scant literature on Campylobacter fetus antimicrobial susceptibility test results. We used a reference test method of agar dilution and provide MICs for a large number of organisms and antimicrobial agents.

Personalisation and embodiment in e-Learning for health professionals: A randomised controlled trial.

PURPOSE: Mayer's theory of multimedia learning proposes that personalisation and embodiment (P/E) can improve outcomes in e-Learning. The authors hypothesised that an e-Learning module enhanced by P/E principles would lead to higher knowledge, perceived P/E and motivation among health care professionals, compared with an unenhanced module. METHODS: The authors conducted a randomised trial comparing two versions of a 30-minute multimedia e-Learning module addressing the antibiotic management of pneumonia. The unenhanced format used slides with voiceover (human voice but no visible speaker), formal language and no specific P/E strategies. The enhanced format additionally implemented P/E strategies including conversational style, polite language, visible author, social congruence, human-like presence and professional presence by subtly changing the script and substituting several short videos of subject matter experts. Participants included pharmacists, physicians and advanced practice providers from three academic and several community hospitals. Outcomes included knowledge, perceived P/E (assessed by the Congruence Personalisation Questionnaire, CPQ), motivation (assessed via the Instructional Materials Motivation Survey [IMMS] and Motivated Strategies for Learning Questionnaire [MSLQ]) and course satisfaction. RESULTS: There were 406 participants including 225 pharmacists, 109 physicians and 72 advanced practice providers. Post-module knowledge was slightly higher for the enhanced versus the unenhanced format, but the difference did not reach statistical significance (adjusted mean difference, 0.04 of 10 possible, [95% CI -0.26, 0.34], p = 0.78; Cohen d 0.02). Participant perceptions of P/E (measured via CPQ) were significantly greater for the enhanced format (difference 0.46 of 5 possible [0.35, 0.56], p < 0.001; Cohen d 0.85), as were motivational features of the e-Learning course (measured via IMMS) (difference 0.14 of 5 possible [0.02, 0.26], p = 0.02; Cohen d 0.24). Participants' overall motivational orientation (measured via MSLQ) and course satisfaction were not significantly different between the two formats (p > 0.05). CONCLUSION: Application of P/E principles to an e-Learning module led to greater perceived P/E and motivational features but did not influence knowledge.

Evaluation of Multisite Programmatic Bundle to Reduce Unnecessary Antibiotic Prescribing for Respiratory Infections: A Retrospective Cohort Study.

Background: The aim of this study was to evaluate the frequency of unnecessary antibiotic prescribing for Tier 3 upper respiratory infection (URI) syndromes across the Mayo Clinic Enterprise before and after a multifaceted antimicrobial stewardship intervention, and to determine ongoing factors associated with antibiotic prescribing and repeat respiratory healthcare contact in the postintervention period. Methods: This was a quasi-experimental, pre/post, retrospective cohort study from 1 January 2019 through 31 December 2022, with 12-month washout during implementation from 1 July 2020 through 30 June 2021. All outpatient encounters, adult and pediatric, from primary care, urgent care, and emergency medicine specialties with a Tier 3 URI diagnosis were included. The intervention was a multifaceted outpatient antibiotic stewardship bundle. The primary outcome was the rate of antibiotic prescribing in Tier 3 encounters. Secondary outcomes included 14-day repeat healthcare contact for respiratory indications and factors associated with persistent unnecessary prescribing. Results: A total of 165 658 Tier 3 encounters, 96 125 in the preintervention and 69 533 in the postintervention period, were included. Following intervention, the prescribing rate for Tier 3 encounters decreased from 21.7% to 11.2% (P < .001). Repeat 14-day respiratory healthcare contact in the no antibiotic group was lower postintervention (9.9.% vs 9.4%; P = .004). Multivariable models indicated that increasing patient age, Charlson comorbidity index, and primary diagnosis selected were the most important factors associated with persistent unnecessary antibiotic prescribing. Conclusions: Outpatient antibiotic stewardship initiatives can reduce unnecessary antibiotic prescribing for Tier 3 URIs without increasing repeat respiratory healthcare contact. Advancing age and number of comorbidities remain risk factors for persistent unnecessary antibiotic prescribing.

Left Ventricular Assist Device: Review of Antimicrobial Prophylaxis Strategies and Incidence of Infections at a Tertiary Care Center 12-Year Experience.

Background: Left ventricular assist devices (LVAD) have an associated infection rate of 13%-80% postimplant. An optimal strategy for surgical infection prophylaxis (SIP) at the time of implantation has not been well defined. We aimed to evaluate the different LVAD implantation antibiotic prophylaxis regimens as well as the incidence of LVAD infection at our institution. Methods: We performed a single-center, retrospective study of patients who underwent LVAD implantation between February 2007 and June 2019. The primary outcome was the incidence of LVAD infection (LVADI), within 3 months and 1 year of placement, between patients who received expanded or narrow-spectrum regimens for SIP. We assessed outcomes using Kaplan-Meier, time-to-first event. We used a noninferiority analysis, which was established if the narrow-spectrum event rate was no more than 5% greater than the expanded-spectrum event rate. Results: We included 399 patients, 305 (76.4%) patients received narrow-spectrum SIP, whereas the remaining 94 (23.6%) patients received the expanded-spectrum regimen. Statistical noninferiority of the narrow spectrum to the multiple drug regimen was demonstrated at both time points, and statistical superiority of the narrow-spectrum group across 12-month follow up was further evident (P = .037). Conclusions: We report evidence supporting noninferiority, or even superiority, of the narrow-spectrum over expanded-spectrum antimicrobial prophylaxis strategy with respect to LVADI. These findings support data-driven antimicrobial prophylaxis strategies.

'How to' Guide for Pharmacist-led Implementation of Beta-Lactam Therapeutic Drug Monitoring in the Critically Ill.

Beta-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 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 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.

Long-term evaluation of clinical success and safety of omadacycline in nontuberculous mycobacteria infections: a retrospective, multicenter cohort of real-world health outcomes.

Infections due to nontuberculous mycobacteria (NTM) continue to increase in prevalence, leading to problematic clinical outcomes. Omadacycline (OMC) is an aminomethylcycline antibiotic with FDA orphan drug and fast-track designations for pulmonary NTM infections, including Mycobacteroides abscessus (MAB). This multicenter retrospective study across 16 U.S. medical institutions from January 2020 to March 2023 examined the long-term clinical success, safety, and tolerability of OMC for NTM infections. The cohort included patients aged ≥18 yr, who were clinically evaluable, and` had been treated with OMC for ≥3 mo without a previous diagnosis of cystic fibrosis. The primary outcome was 3 mo clinical success, with secondary outcomes including clinical improvement and mortality at 6- and 12 mo, persistence or reemergence of infection, adverse effects, and reasons for OMC utilization. Seventy-five patients were included in this analysis. Most patients were female (48/75, 64.0%) or Caucasian (58/75, 77.3%), with a median (IQR) age of 59 yr (49-67). Most had NTM pulmonary disease (33/75, 44.0%), skin and soft tissue disease (19/75, 25.3%), or osteomyelitis (10/75, 13.3%), and Mycobacterium abscessus (60/75, 80%) was the most commonly isolated NTM pathogen. The median (IQR) treatment duration was 6 mo (4 - 14), and the most commonly co-administered antibiotic was azithromycin (33/70, 47.1%). Three-month clinical success was observed in 80.0% (60/75) of patients, and AEs attributable to OMC occurred in 32.0% (24/75) of patients, leading to drug discontinuation in 9.3% (7/75).

A Pharmacovigilance Analysis of Daptomycin Use Based on CLSI Susceptible Dose-Dependent Category.

INTRODUCTION: Daptomycin doses 8-12 mg/kg are recommended for susceptible dose-dependent Enterococcus species. However, data remain limited on safety outcomes of such dosing, compared to standard 4-6 mg/kg dosing. METHODS: In this retrospective cohort study, patients were stratified into daptomycin standard-dose (≤ 6.5 mg/kg) versus high-dose (≥ 7.5 mg/kg) groups. The primary outcome was daptomycin safety based on a composite of creatine kinase elevation, daptomycin-related peripheral blood eosinophilia, eosinophilic pneumonitis, alanine aminotransferase elevation, and alkaline phosphatase elevation. A secondary aim was to identify risk factors for daptomycin adverse effects. Inclusion criteria were age ≥ 18 years old, daptomycin receipt for ≥ 48 h, and Enterococcus cultures with a daptomycin minimal inhibitory concentration 2-4 mg/L. RESULTS: A total of 119 patients were included for analysis. Median daptomycin doses were 6.0 mg/kg (IQR 5.4, 6.1) and 8.1 mg/kg (IQR 7.9, 9.6) in the standard- and high-dose cohorts, respectively. Median durations were 13.5 days (standard-dose) and 16 days (high-dose) (p = 0.02). The composite safety endpoint occurred in 32.0% of the standard-dose group and 32.5% of the high-dose group (p = 0.96). Daptomycin was dose-reduced or held in 8.1% of patients experiencing an adverse effect. Concurrent antihistamine usage was associated with the composite outcome; however, there was no association with daptomycin dose or concurrent statin use. CONCLUSION: High-dose daptomycin was not associated with increased laboratory abnormalities or adverse drug reactions compared to standard-dose daptomycin.

Native mitral valve infective endocarditis due to Dolosigranulum pigrum.

Dolosigranulum pigrum is an anaerobic, gram-positive coccus rarely identified as a pathogenic organism. However, case reports have suggested D. pigrum as a causative pathogen in bacteremia, nosocomial pneumonia, ventilator-associated pneumonia, synovitis, cholecystitis, and ophthalmologic infections. Herein, we present the first case of Dolosigranulum pigrum causing native mitral valve infective endocarditis. With the exception of erythromycin, the isolate displayed favorable minimum inhibitory concentrations (MIC) to all other antibiotics tested, including beta-lactams, levofloxacin, and vancomycin. The patient was successfully treated with a 6-week course of intravenous (IV) ceftriaxone followed by robotically assisted cardiac valve repair.

Failure of mecA/mecC PCR Testing to Accurately Predict Oxacillin Resistance in a Patient with Staphylococcus aureus Infective Endocarditis.

Genotypic testing for mecA/mecC is heavily relied upon for rapid optimization of antimicrobial therapy in infections due to Staphylococcus aureus. Little is known regarding optimal reporting and/or therapy for patients demonstrating lack of genotypic evidence of mecA or mecC but phenotypic oxacillin resistance. We report a case of a 77-year-old patient with S. aureus bloodstream infection and infective endocarditis with discordance between mecA/mecC genotypic results and phenotypic susceptibility testing.

Heartbreaking Decisions: The Dogma and Uncertainties of Antimicrobial Therapy in Infective Endocarditis.

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.

Comparison of Oral and Intravenous Definitive Antibiotic Therapy for Beta-Hemolytic Streptococcus Species Bloodstream Infections from Soft Tissue Sources: a Propensity Score-Matched Analysis.

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. We conducted a retrospective study of adults with beta-hemolytic streptococcal BSI from a primary skin/soft tissue source from 2015 to 2020. Patients transitioned to oral antibiotics within 7 days of treatment initiation were compared to those who continued intravenous therapy, after propensity score matching. The primary outcome was 30-day treatment failure (composite of mortality, infection relapse, and hospital readmission). A prespecified 10% noninferiority margin was used for the primary outcome. We identified 66 matched pairs of patients treated with oral and intravenous antibiotics as definitive therapy. Based on an absolute difference in 30-day treatment failure of 13.6% (95% confidence interval 2.4 to 24.8%), the noninferiority of oral therapy was not confirmed (P = 0.741); on the contrary, the superiority of intravenous antibiotics is suggested by this difference. Acute kidney injury occurred in two patients who received intravenous treatment and zero who received oral therapy. No patients experienced deep vein thrombosis or other vascular complications related to treatment. In patients treated for beta-hemolytic streptococcal BSI, those who transitioned to oral antibiotics by day 7 showed higher rates of 30-day treatment failure than propensity-matched patients. This difference may have been driven by underdosing of oral therapy. Further investigation into optimal antibiotic choice, route, and dosing for definitive therapy of BSI is needed.

A Broad Spectrum of Possibilities: Spectrum Scores as a Unifying Metric of Antibiotic Utilization.

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.