Difficult-to-treat (DTR) Pseudomonas aeruginosa harboring Verona-Integron metallo-ß-lactamase (blaVIM): infection management and molecular analysis.

Pseudomonas aeruginosa harboring Verona Integron-encoded metallo-ß-lactamase enzymes (VIM-CRPA) have been associated with infection outbreaks in several parts of the world. In the US, however, VIM-CRPA remain rare. Starting in December 2018, we identified a cluster of cases in our institution. Herein, we present our epidemiological investigation and strategies to control/manage these challenging infections. This study was conducted in a large academic healthcare system in Miami, FL, between December 2018 and January 2022. Patients were prospectively identified via rapid molecular diagnostics when cultures revealed carbapenem-resistant P. aeruginosa. Alerts were received in real time by the antimicrobial stewardship program and infection prevention teams. Upon alert recognition, a series of interventions were performed as a coordinated effort. A retrospective chart review was conducted to collect patient demographics, antimicrobial therapy, and clinical outcomes. Thirty-nine VIM-CRPA isolates led to infection in 21 patients. The majority were male (76.2%); the median age was 52 years. The majority were mechanically ventilated (n = 15/21; 71.4%); 47.6% (n = 10/21) received renal replacement therapy at the time of index culture. Respiratory (n = 20/39; 51.3%) or bloodstream (n = 13/39; 33.3%) were the most common sources. Most infections (n = 23/37; 62.2%) were treated with an aztreonam-avibactam regimen. Six patients (28.6%) expired within 30 days of index VIM-CRPA infection. Fourteen isolates were selected for whole genome sequencing. Most of them belonged to ST111 (12/14), and they all carried blaVIM-2 chromosomally. This report describes the clinical experience treating serious VIM-CRPA infections with either aztreonam-ceftazidime/avibactam or cefiderocol in combination with other agents. The importance of implementing infection prevention strategies to curb VIM-CRPA outbreaks is also demonstrated.

Navigating the Challenges of Candida auris Colonization in Rehabilitation Settings.

ABSTRACT: Candida auris is a highly transmissible yeast that is capable of causing invasive and fatal infections, particularly among persons with underlying medical conditions. Its incidence is rising, especially among patients cared for in post-acute care facilities. Individuals colonized with the yeast may be cared for in inpatient rehabilitation settings, without heightened risk for invasive infection and/or transmission to others, as long as appropriate infection control measures are followed. This article reviews key information for rehabilitation nurses caring for persons with C. auris , including risk factors for infection, the need for contact precautions, appropriate disinfection practices for therapy and diagnostic equipment, and critical components of safe transitions in the care of these patients.

An international prospective study of INICC analyzing the incidence and risk factors for catheter-associated urinary tract infections in 235 ICUs across 8 Asian Countries.

BACKGROUND: Identify urinary catheter (UC)-associated urinary tract infections (CAUTI) incidence and risk factors (RF) in 235 ICUs in 8 Asian countries: India, Malaysia, Mongolia, Nepal, Pakistan, the Philippines, Thailand, and Vietnam. METHODS: From January 1, 2014, to February 12, 2022, we conducted a prospective cohort study. To estimate CAUTI incidence, the number of UC days was the denominator, and CAUTI was the numerator. To estimate CAUTI RFs, we analyzed 11 variables using multiple logistic regression. RESULTS: 84,920 patients hospitalized for 499,272 patient days acquired 869 CAUTIs. The pooled CAUTI rate per 1,000 UC-days was 3.08; for those using suprapubic-catheters (4.11); indwelling-catheters (2.65); trauma-ICU (10.55), neurologic-ICU (7.17), neurosurgical-ICU (5.28); in lower-middle-income countries (3.05); in upper-middle-income countries (1.71); at public-hospitals (5.98), at private-hospitals (3.09), at teaching-hospitals (2.04). The following variables were identified as CAUTI RFs: Age (adjusted odds ratio [aOR] = 1.01; 95% CI = 1.01-1.02; P < .0001); female sex (aOR = 1.39; 95% CI = 1.21-1.59; P < .0001); using suprapubic-catheter (aOR = 4.72; 95% CI = 1.69-13.21; P < .0001); length of stay before CAUTI acquisition (aOR = 1.04; 95% CI = 1.04-1.05; P < .0001); UC and device utilization-ratio (aOR = 1.07; 95% CI = 1.01-1.13; P = .02); hospitalized at trauma-ICU (aOR = 14.12; 95% CI = 4.68-42.67; P < .0001), neurologic-ICU (aOR = 14.13; 95% CI = 6.63-30.11; P < .0001), neurosurgical-ICU (aOR = 13.79; 95% CI = 6.88-27.64; P < .0001); public-facilities (aOR = 3.23; 95% CI = 2.34-4.46; P < .0001). DISCUSSION: CAUTI rate and risk are higher for older patients, women, hospitalized at trauma-ICU, neurologic-ICU, neurosurgical-ICU, and public facilities. All of them are unlikely to change. CONCLUSIONS: It is suggested to focus on reducing the length of stay and the Urinary catheter device utilization ratio, avoiding suprapubic catheters, and implementing evidence-based CAUTI prevention recommendations.

Impact of In-house Candida auris Polymerase Chain Reaction Screening on Admission on the Incidence Rates of Surveillance and Blood Cultures With C. auris and Associated Cost Savings.

Background: The impact of strategies for rapid diagnostic screening of Candida auris on hospital operations has not been previously characterized. We describe the implementation of in-house polymerase chain reaction (PCR) testing on admission for screening of colonization with C. auris, associated process improvements, and financial impact. Methods: This study was conducted across an integrated health system. Patients were tested based on risk factors for C. auris carriage. Pre-intervention, the PCR was sent out to a reference laboratory, and postintervention was performed in-house. Changes in the incidence rates (IRs) of C. auris present on admission (CA-POA) and C. auris hospital-onset fungemia (CA-HOF) were assessed using interrupted time series analysis. The economic impact on isolation and testing costs was calculated. Results: Postintervention, the IR of CA-POA doubled (IRR, 2.57; 95% CI, 1.16-5.69; P = .02) compared with the pre-intervention period. The baseline rate of CA-HOF was increasing monthly by 14% (95% CI, 1.05-1.24; P = .002) pre-intervention, while during the postintervention period there was a change in slope with a monthly decrease in IR of 13% (95% CI, 0.80-0.99; P = .02). The median turnaround time (TAT) of the results (interquartile range) was reduced from 11 (8-14) days to 2 (1-3) days. Savings were estimated to be between $772 513.10 and $3 730 480.26. Conclusions: By performing in-house PCR for screening of C. auris colonization on admission, we found a doubling of CA-POA rates, a subsequent decrease in CA-HOF rates, reduced TAT for PCR results, and more efficient use of infection control measures. In-house testing was cost-effective in a setting of relatively high prevalence among individuals with known risk factors.

Effectiveness of a sodium hypochlorite isotonic solution in decolonization of patients with Candida auris: Learnings from a county health care system.

BACKGROUND: Candida auris (CA) is an organism that has spread globally over the last decade. We conducted a quality improvement project with the aim of decreasing or eliminating skin colonization of patients with CA through a modified bathing protocol. METHODS: An isotonic hypochlorite solution was added to routine bathing protocols for hospitalized patients colonized with CA. Weekly skin swabs from axillary and inguinal areas were tested for the presence of CA using polymerase chain reaction and culture. Multidisciplinary efforts, such as environmental terminal cleaning, dedicated equipment, education, and signage were reinforced among staff to improve patient outcomes. RESULTS: A total of 24 patients were included. After 4 weeks of a modified bathing protocol, 81.2% of the patients remained colonized with CA. Three patients were discharged safely to their homes and 3 were transferred to long-term care acute hospitals. Nine patients remained hospitalized after 60 days. Localized rash was reported in 3 patients, which resolved after discontinuation of the product. CONCLUSIONS: Modification of our bathing protocols by including an isotonic hypochlorite solution did not lead to skin decolonization of CA. Further studies are needed to identify effective measures to eradicate, eliminate or reduce colonization.

Disrupting the infectious disease ecosystem in the digital precision health era innovations and converging emerging technologies.

This commentary explores the convergence of precision health and evolving technologies, including the critical role of artificial intelligence (AI) and emerging technologies in infectious diseases (ID) and microbiology. We discuss their disruptive impact on the ID ecosystem and examine the transformative potential of frontier technologies in precision health, public health, and global health when deployed with robust ethical and data governance guardrails in place.

A Multicenter Retrospective Cohort Study to Characterize Patients Hospitalized With Multisystem Inflammatory Syndrome in Adults and Coronavirus Disease 2019 in the United States, 2020-2021.

BACKGROUND: The diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-associated multisystem inflammatory syndrome in adults (MIS-A) requires distinguishing it from acute coronavirus disease 2019 (COVID-19) and may affect clinical management. METHODS: In this retrospective cohort study, we applied the US Centers for Disease Control and Prevention case definition to identify adults hospitalized with MIS-A at 6 academic medical centers from 1 March 2020 to 31 December 2021. Patients MIS-A were matched by age group, sex, site, and admission date at a 1:2 ratio to patients hospitalized with acute symptomatic COVID-19. Conditional logistic regression was used to compare demographic characteristics, presenting symptoms, laboratory and imaging results, treatments administered, and outcomes between cohorts. RESULTS: Through medical record review of 10 223 patients hospitalized with SARS-CoV-2-associated illness, we identified 53 MIS-A cases. Compared with 106 matched patients with COVID-19, those with MIS-A were more likely to be non-Hispanic black and less likely to be non-Hispanic white. They more likely had laboratory-confirmed COVID-19 ≥14 days before hospitalization, more likely had positive in-hospital SARS-CoV-2 serologic testing, and more often presented with gastrointestinal symptoms and chest pain. They were less likely to have underlying medical conditions and to present with cough and dyspnea. On admission, patients with MIS-A had higher neutrophil-to-lymphocyte ratio and higher levels of C-reactive protein, ferritin, procalcitonin, and D-dimer than patients with COVID-19. They also had longer hospitalization and more likely required intensive care admission, invasive mechanical ventilation, and vasopressors. The mortality rate was 6% in both cohorts. CONCLUSIONS: Compared with patients with acute symptomatic COVID-19, adults with MIS-A more often manifest certain symptoms and laboratory findings early during hospitalization. These features may facilitate diagnosis and management.

A retrospective study on 198 mpox cases in South Florida: Clinical characteristics and outcomes with focus on human immunodeficiency virus status.

BACKGROUND: Men who have sex with men (MSM) and persons living with human immunodeficiency virus (PLWH) were disproportionately affected by global mpox outbreak in 2022. In this retrospective review, we describe epidemiology and clinical characteristics of mpox infection in South Florida with a focus on human immunodeficiency virus (HIV) status. METHODS: This was a retrospective observational study of 198 adult patients with confirmed diagnosis of mpox between 01 January 2020, and 10 September 2022, in two large health systems in South Florida. A descriptive analysis was performed to summarize demographic, clinical and laboratory characteristics, and outcomes of the patients. RESULTS: Young male patients and PLWH were disproportionately represented among patients with mpox. HIV positive patients were less likely to have adenopathy and myalgia and were more likely to have oral or facial lesions. 22.7% of studied patients were diagnosed with one or more concurrent STI at the time of mpox diagnosis. CONCLUSIONS: We suggest screening for sexually transmitted infections and HIV for patients diagnosed with mpox. We suggest prompt consultation or referral to infectious disease specialist if needed for the patients who are diagnosed with mpox especially in the severely immunocompromised host.

Impact of a real-time diagnostic and antimicrobial stewardship workflow on time to appropriate therapy for infections caused by multidrug-resistant Gram-negative organisms.

INTRODUCTION: Multidrug-resistant (MDR) Gram-negative organisms cause life-threatening infections, and the incidence is rising globally. Timely therapy for these infections has a direct impact on patient survival. This study aimed to determine the impact of a multidisciplinary diagnostic and antimicrobial stewardship (AMS) workflow on time to appropriate therapy (TAP) for these infections using novel beta-lactam/beta-lactamase inhibitors. METHODS: This was a retrospective quasi-experimental study of adult patients with carbapenem-resistant Enterobacterales (CRE) and multidrug-resistant Pseudomonas (MDR PsA) infections at a 1500 bed university hospital. Included patients who received ≥ 72 hours of ceftazidime-avibactam (CZA) or ceftolozane-tazobactam (C/T) from December 2017 to December 2019. During the pre-intervention period (December 2017 to December 2018), additional susceptibilities (including CZA and C/T) were performed only upon providers' request. In 2019, reflex algorithms were implemented for faster identification and testing of all CRE/MDR PsA isolates. Results were communicated in real-time to the AMS team to tailor therapy. RESULTS: A total of 99 patients were included, with no between-group differences at baseline. The median age was 60 years and 56 (56.7%) were in intensive care at the time of culture collection. Identified organisms included 71 (71.7%) MDR PsA and 26 CRE, of which 18 were carbapenemase producers (Klebsiella-producing carbapenemase = 12, New Delhi metallo-ß-lactamase = 4, Verona integron-encoded metallo-ß-lactamase = 2). The most common infections were pneumonia (49.5%) and bacteraemia (30.3%). A decrease was found in median TAP (103 [IQR 76.0-156.0] vs. 75 [IQR 56-100] hours; P < 0.001). Median time from culture collection to final susceptibility results was shorter in the post-intervention group (123 vs. 93 hours; P < 0.001). CONCLUSION: This study identified improvement in TAP in MDR PsA and CRE infections with implementation of a reflex microbiology workflow and multidisciplinary antimicrobial stewardship initiatives.

Preventing Surgical Site Infections: Implementing Strategies Throughout the Perioperative Continuum.

Surgical site infections (SSIs) are a considerable cause of patient morbidity and mortality and are associated with increased hospital lengths of stay as well as increased health care costs to both patients and health care facilities. Substantial advances have been made in infection control practices throughout the perioperative setting to prevent SSIs and improve patient quality of care. Preventing and reducing SSIs requires a multifaceted approach encompassing the continuum of medical and surgical care. This article reviews four major infection prevention guidelines and provides an updated summary of effective strategies that perioperative team members can implement for the prevention of SSIs preoperatively, intraoperatively, and postoperatively.

Combined Use of RT-qPCR and NGS for Identification and Surveillance of SARS-CoV-2 Variants of Concern in Residual Clinical Laboratory Samples in Miami-Dade County, Florida.

Over the course of the COVID-19 pandemic, SARS-CoV-2 variants of concern (VOCs) with increased transmissibility and immune escape capabilities, such as Delta and Omicron, have triggered waves of new COVID-19 infections worldwide, and Omicron subvariants continue to represent a global health concern. Tracking the prevalence and dynamics of VOCs has clinical and epidemiological significance and is essential for modeling the progression and evolution of the COVID-19 pandemic. Next generation sequencing (NGS) is recognized as the gold standard for genomic characterization of SARS-CoV-2 variants, but it is labor and cost intensive and not amenable to rapid lineage identification. Here we describe a two-pronged approach for rapid, cost-effective surveillance of SARS-CoV-2 VOCs by combining reverse-transcriptase quantitative polymerase chain reaction (RT-qPCR) and periodic NGS with the ARTIC sequencing method. Variant surveillance by RT-qPCR included the commercially available TaqPath COVID-19 Combo Kit to track S-gene target failure (SGTF) associated with the spike protein deletion H69-V70, as well as two internally designed and validated RT-qPCR assays targeting two N-terminal-domain (NTD) spike gene deletions, NTD156-7 and NTD25-7. The NTD156-7 RT-qPCR assay facilitated tracking of the Delta variant, while the NTD25-7 RT-qPCR assay was used for tracking Omicron variants, including the BA.2, BA.4, and BA.5 lineages. In silico validation of the NTD156-7 and NTD25-7 primers and probes compared with publicly available SARS-CoV-2 genome databases showed low variability in regions corresponding to oligonucleotide binding sites. Similarly, in vitro validation with NGS-confirmed samples showed excellent correlation. RT-qPCR assays allow for near-real-time monitoring of circulating and emerging variants allowing for ongoing surveillance of variant dynamics in a local population. By performing periodic sequencing of variant surveillance by RT-qPCR methods, we were able to provide ongoing validation of the results obtained by RT-qPCR screening. Rapid SARS-CoV-2 variant identification and surveillance by this combined approach served to inform clinical decisions in a timely manner and permitted better utilization of sequencing resources.

Multisite Detection of Tn1549-Mediated vanB Vancomycin Resistance in Multidrug-Resistant Enterococcus faecalis ST6 in Texas and Florida.

In the United States, vanB-mediated resistance in enterococci is rare. We characterized three sequence type (ST) 6, vancomycin-resistant Enterococcus faecalis isolates causing bacteremia in unique patients in spatiotemporally distinct settings. Isolates were recovered between 2018 and 2020 in two cities in the United States (Houston, TX; Miami, FL). The isolates harbored the vanB operon on a chromosomally located Tn1549 transposon, and epidemiological data suggested multiple introductions of the vanB gene cluster into ST6 E. faecalis.

Rapid molecular testing for antimicrobial stewardship and solid organ transplantation.

BACKGROUND: Several molecular platforms now exist for early detection of infectious pathogens. In this review, we present the currently available literature summarizing clinical outcomes using rapid diagnostic tests (RDTs) in the solid organ transplant (SOT) population. We also present potential benefits and drawbacks of these technologies for SOT patients. METHODS: We completed a PubMed search querying for 31 specific RDTs AND ("SOT"). We also queried PubMed for studies on RDT outcomes in the general population. References of the resulting relevant studies were reviewed and incorporated if the study population included at least one SOT patient. All culture specimen types were included. Only full-text peer-reviewed publications in English were examined. RESULTS: Our search yielded eleven studies. Across these studies, integrating RDTs with ASP intervention led to faster species identification and susceptibility results, faster time-to-optimal therapy, decreased hospital length-of-stay and costs, and decreased mortality. Potential drawbacks of RDTs in the SOT population included: overdiagnosis due to increased sensitivity (i.e., Clostridium difficile), decreased yield of tests for respiratory pathogens, and lack of identification of important pathogens in this population such as, Aspergillus species. CONCLUSIONS: Although there is a scarcity of studies involving SOT patients, current available data suggests that the use of RDTs helps improve patient outcomes and minimizes inappropriate antimicrobial use when coupled with proactive ASPs. Future studies should focus on clinical outcomes in SOT patients specifically, as well as how to optimize the use of RDTs in conjunction with traditional microbiology methods.

Challenges and opportunities in stewardship among solid organ transplant recipients with Candida auris bloodstream infections.

BACKGROUND: Candida auris is an emerging nosocomial pathogen worldwide. However, there has been little published on the management of C. auris in solid organ transplant recipients. METHODS: A single-center, retrospective cohort study was conducted to evaluate C. auris bloodstream infections in solid organ transplant recipients between January 2020 and December 2021. Patient-related and outcomes data were extracted from electronic medical records. RESULTS: Of the 42 patients identified with C. auris bloodstream infections, five were in solid organ transplant recipients (1 heart, 3 liver, and 1 combined liver-kidney). The median time to fungemia from hospital admission was 43 days, and the median time to fungemia from transplant was 18 days. All patients received micafungin as initial treatment, at a median of 6 hours from pathogen detection. Four patients achieved blood clearance, two patients had persistent fungemia, and two patients developed secondary complications from hematogenous spread. One patient died, resulting in a mortality rate of 20%. CONCLUSIONS: Solid organ transplant recipients are at high risk for developing C. auris bloodstream infections. In order to prevent graft loss and mortality, best practices for the management of C.auris should include rapid screening, diagnosis, and treatment. While echinocandins are considered first-line, antifungal selection should be based on susceptibilities and site of infection. Data to support routine use of combination therapy are lacking, however there may be a role for refractory cases. Prevention efforts against C. auris infection are especially important given the lack of effective decolonization strategies. For transplant recipients, hospitals should seek opportunities to restore patients' gut microbiome by curtailing unnecessary hospital procedures and inappropriate antimicrobial use. Further research and national guidelines are needed to better direct stewardship in this field.

Is the Omicron variant truly less virulent in solid organ transplant recipients?

Solid organ transplant (SOT) recipients are at high risk for severe disease with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Emerging variants of concern have disproportionately affected this population. Data on severity and outcomes with the Omicron variant in SOT recipients are limited. Thus we conducted this single-center, retrospective cohort study of SOT recipients diagnosed with SARS-CoV-2 infection from December 18, 2021 to January 18, 2022, when prevalence of the Omicron variant was more than 80%-95% in the community. Univariate and multivariate logistic regression analysis was performed to identify risk factors for hospital admission. We identified 166 SOT patients: 112 (67.5%) kidney, 22 (13.3%) liver, 10 (6.0%) lung, seven (4.2%) heart, and 15 (9.0%) combined transplants. SARS-CoV-2 vaccine series was completed in 59 (35.5%) recipients. Ninety-nine (59.6%) and 13 (7.8%) recipients received casirivimab/imdevimab and sotrovimab, respectively. Fifty-three (32%) recipients required hospital admission, of which 19 (35.8%) required intensive care unit level of care. Median follow-up was 50 (interquartile range, 25-59) days, with mortality reported in six (3.6%) patients. Risk factors identified for hospital admission were African American race (p < .001, odds ratio [OR] 4.00, 95% confidence interval [CI] 1.84-8.70), history of coronary artery disease (p = .031, OR 3.50, 95% CI 1.12-10.87), and maintenance immunosuppression with corticosteroids (p = .048, OR 2.00, 95% CI 1.01-4.00). In conclusion, contrary to that in the general population, we found a higher hospital admission rate in SOT recipients with omicron variant infection. Further studies to investigate the efficacy of newer treatments are necessary, even as outcomes continue to improve.

Mycobacterium abscessus Infections in Solid Organ Transplant Recipients: Single-Center Experience in the United States, 2013-2018.

Background: Mycobacterium abscessus is increasingly recognized as a human pathogen causing life-threatening infections in immunocompromised patients. There is a paucity of data around this topic in solid organ transplant (SOT) recipients. Methods: This work was a single-center retrospective cohort study of all SOT recipients with a positive culture for M abscessus between 2013 and 2018. Results: A total of 20 patients (55% female) met inclusion criteria, including 1 kidney recipient (5.0%), 2 liver recipients (10.0%), 12 lung recipients (60.0%), 1 heart recipient (5.0%), and 4 combined organ recipients (20.0%). The median time from SOT to infection was 100 days (range, 30-431 days). Thirteen (65.0%) patients (1 kidney, 1 heart, 7 lung, 1 liver, 1 intestine, and 2 multivisceral) were treated with a median duration of 185 antibiotic days (range, 20-523 days). Among them, M abscessus was isolated from respiratory samples in 8 and nonrespiratory samples in 5; 4 of 13 (30.8%) patients had treatment failure and 3 of 13 (23.1%) had unrelated deaths within 1 year after diagnosis. Seven patients (5 lung transplant recipients) with the organism isolated from respiratory samples were not treated as their cultures represented airway colonization or contamination; of those, 2 (28.6%) died (unrelated to infection) and 5 (71.4%) were alive without the infection after 1 year of follow-up. Conclusions: Mycobacterium abscessus infections affect SOT recipients with a high proportion of clinical failures. However, in lung recipients, not all positive cultures correlated with infection, and without treatment some patients had good clinical outcomes. Thus, differentiating colonization from infection is important, and infection prevention measures and novel therapeutic agents are needed for SOT recipients.

Genomic heterogeneity underlies multidrug resistance in Pseudomonas aeruginosa: A population-level analysis beyond susceptibility testing.

BACKGROUND: Pseudomonas aeruginosa is a persistent and difficult-to-treat pathogen in many patients, especially those with Cystic Fibrosis (CF). Herein, we describe a longitudinal analysis of a series of multidrug resistant (MDR) P. aeruginosa isolates recovered in a 17-month period, from a young female CF patient who underwent double lung transplantation. Our goal was to understand the genetic basis of the observed resistance phenotypes, establish the genomic population diversity, and define the nature of sequence evolution over time. METHODS: Twenty-two sequential P. aeruginosa isolates were obtained within a 17-month period, before and after a double-lung transplant. At the end of the study period, antimicrobial susceptibility testing, whole genome sequencing (WGS), phylogenetic analyses and RNAseq were performed in order to understand the genetic basis of the observed resistance phenotypes, establish the genomic population diversity, and define the nature of sequence changes over time. RESULTS: The majority of isolates were resistant to almost all tested antibiotics. A phylogenetic reconstruction revealed 3 major clades representing a genotypically and phenotypically heterogeneous population. The pattern of mutation accumulation and variation of gene expression suggested that a group of closely related strains was present in the patient prior to transplantation and continued to change throughout the course of treatment. A trend toward accumulation of mutations over time was observed. Different mutations in the DNA mismatch repair gene mutL consistent with a hypermutator phenotype were observed in two clades. RNAseq performed on 12 representative isolates revealed substantial differences in the expression of genes associated with antibiotic resistance and virulence traits. CONCLUSIONS: The overwhelming current practice in the clinical laboratories setting relies on obtaining a pure culture and reporting the antibiogram from a few isolated colonies to inform therapy decisions. Our analyses revealed significant underlying genomic heterogeneity and unpredictable evolutionary patterns that were independent of prior antibiotic treatment, highlighting the need for comprehensive sampling and population-level analysis when gathering microbiological data in the context of CF P. aeruginosa chronic infection. Our findings challenge the applicability of antimicrobial stewardship programs based on single-isolate resistance profiles for the selection of antibiotic regimens in chronic infections such as CF.

Contemporary Clinical and Molecular Epidemiology of Vancomycin-Resistant Enterococcal Bacteremia: A Prospective Multicenter Cohort Study (VENOUS I).

BACKGROUND: Vancomycin-resistant enterococci (VRE) are major therapeutic challenges. Prospective contemporary data characterizing the clinical and molecular epidemiology of VRE bloodstream infections (BSIs) are lacking. METHODS: The Vancomycin-Resistant Enterococcal BSI Outcomes Study (VENOUS I) is a prospective observational cohort of adult patients with enterococcal BSI in 11 US hospitals. We included patients with Enterococcus faecalis or Enterococcus faecium BSI with ≥1 follow-up blood culture(s) within 7 days and availability of isolate(s) for further characterization. The primary study outcome was in-hospital mortality. Secondary outcomes were mortality at days 4, 7, 10, 12, and 15 after index blood culture. A desirability of outcome ranking was constructed to assess the association of vancomycin resistance with outcomes. All index isolates were subjected to whole genome sequencing. RESULTS: Forty-two of 232 (18%) patients died in hospital and 39 (17%) exhibited microbiological failure (lack of clearance in the first 4 days). Neutropenia (hazard ratio [HR], 3.13), microbiological failure (HR, 2.4), VRE BSI (HR, 2.13), use of urinary catheter (HR, 1.85), and Pitt BSI score ≥2 (HR, 1.83) were significant predictors of in-hospital mortality. Microbiological failure was the strongest predictor of in-hospital mortality in patients with E faecium bacteremia (HR, 5.03). The impact of vancomycin resistance on mortality in our cohort changed throughout the course of hospitalization. Enterococcus faecalis sequence type 6 was a predominant multidrug-resistant lineage, whereas a heterogeneous genomic population of E faecium was identified. CONCLUSIONS: Failure of early eradication of VRE from the bloodstream is a major factor associated with poor outcomes.

Evaluation of the Infectious Diseases Society of America's Core Antimicrobial Stewardship Curriculum for Infectious Diseases Fellows.

BACKGROUND: Antimicrobial stewardship (AS) programs are required by Centers for Medicare and Medicaid Services and should ideally have infectious diseases (ID) physician involvement; however, only 50% of ID fellowship programs have formal AS curricula. The Infectious Diseases Society of America (IDSA) formed a workgroup to develop a core AS curriculum for ID fellows. Here we study its impact. METHODS: ID program directors and fellows in 56 fellowship programs were surveyed regarding the content and effectiveness of their AS training before and after implementation of the IDSA curriculum. Fellows' knowledge was assessed using multiple-choice questions. Fellows completing their first year of fellowship were surveyed before curriculum implementation ("pre-curriculum") and compared to first-year fellows who complete the curriculum the following year ("post-curriculum"). RESULTS: Forty-nine (88%) program directors and 105 (67%) fellows completed the pre-curriculum surveys; 35 (64%) program directors and 79 (50%) fellows completed the post-curriculum surveys. Prior to IDSA curriculum implementation, only 51% of programs had a "formal" curriculum. After implementation, satisfaction with AS training increased among program directors (16% to 68%) and fellows (51% to 68%). Fellows' confidence increased in 7/10 AS content areas. Knowledge scores improved from a mean of 4.6 to 5.1 correct answers of 9 questions (P = .028). The major hurdle to curriculum implementation was time, both for formal teaching and for e-learning. CONCLUSIONS: Effective AS training is a critical component of ID fellowship training. The IDSA Core AS Curriculum can enhance AS training, increase fellow confidence, and improve overall satisfaction of fellows and program directors.