Comparing clinical, microbiological and genetic definitions of relapse in patients with subsequent episodes of MRSA bone and joint infection.

Background: Differentiation of a relapse from a new infection is challenging in patients with a recurrent bone or joint infection (BJI). We compared clinical, microbiological, and genomic definitions of relapse among patients with methicillin resistant Staphylococcus aureus (MRSA) BJI.

Methods: All MRSA isolates obtained from BJIs between July 2018 and December 2022 from patients with at least 2 episodes of BJI from two U.

Methicillin-Resistant Staphylococcus aureus Bacteremia Relapses Show Diverse Genomic Profiles but Convergence in Bacteremia-Associated Genes.

Background: Recurrence of methicillin-resistant Staphylococcus aureus (MRSA) bacteremia is a high risk complication for patients. Distinguishing persistent lineages from new infections is not standardized across clinical studies.

Methods: We investigated factors contributing to recurrence of MRSA bacteremia among subjects in Philadelphia, Pennsylvania.

Multidisciplinary Guidance to Care for Persons With Xylazine-Associated Wounds.

Xylazine, an adulterant of unregulated opioid supplies, is increasingly prevalent in the United States and associated with distinctive wounds. Xylazine-associated wounds (XAWs) are primarily noted in the extremities and are not always associated with injection drug use. XAWs are often chronic and can become superinfected, posing a great challenge to clinical care.

Comparative performance of sponge versus flocked swabs for culture-based and metagenomic detection of microbial contamination in the healthcare environment.

Background: Identifying optimal methods for sampling surfaces in the healthcare environment is critical for future research requiring the identification of multidrug-resistant organisms (MDROs) on surfaces.

Methods: We compared 2 swabbing methods, use of a flocked swab versus a sponge-stick, for recovery of MDROs by both culture and recovery of bacterial DNA via quantitative 16S polymerase chain reaction (PCR). This comparison was conducted by assessing swab performance in a longitudinal survey of MDRO contamination in hospital rooms.

Genomic investigation of MRSA bacteremia relapse reveals diverse genomic profiles but convergence in bacteremia-associated genes.

Background: Recurrence of methicillin-resistant (MRSA) bacteremia is a high risk complication for patients. Distinguishing persistent lineages from new infections is not standardized across clinical studies.

Methods: We investigated factors contributing to recurrence of MRSA bacteremia among subjects in Philadelphia, Pennsylvania.

Clinical presentation, treatment, and antimicrobial susceptibility of 155 sequential infections.

Unlabelled: is known to be virulent, but there are few large-scale epidemiologic studies of this species to define types of infection, susceptibility patterns, and severity. isolates from any culture at four U.S.

Strain Differences in Bloodstream and Skin Infection: Methicillin-Resistant Isolated in 2018-2021 in a Single Health System.

is a common cause of skin and soft-tissue infections (SSTIs) and has become the most common cause of bloodstream infections (BSIs) in recent years, but whether the strains causing these two clinical syndromes overlap has not been studied adequately. USA300/500 (clonal complex [CC] 8-sequence type [ST] 8) and USA100 (CC5-ST5) have dominated among methicillin-resistant (MRSA) strains in the United States since the early 2000s. We compared the genomes of unselected MRSA isolates from 131 SSTIs with those from 145 BSIs at a single US center in overlapping periods in 2018-2021.

Factors associated with foreign body infection in methicillin-resistant bacteremia.

Background: We aimed to compare patient characteristics, MRSA sequence types, and biofilm production of MRSA strains that did and did not cause a foreign body infection in patients with MRSA bloodstream infections (BSI).

Methods: All adult patients with MRSA BSI hospitalized in two hospitals were identified by clinical microbiology laboratory surveillance. Only patients who had at least one implanted foreign body during the episode of BSI were included.

Antibiotic Prescribing Patterns for Respiratory Tract Illnesses Following the Conclusion of an Education and Feedback Intervention in Primary Care.

Background: A study previously conducted in primary care practices found that implementation of an educational session and peer comparison feedback was associated with reduced antibiotic prescribing for respiratory tract diagnoses (RTDs). Here, we assess the long-term effects of this intervention on antibiotic prescribing following cessation of feedback.

Methods: RTD encounters were grouped into tiers based on antibiotic prescribing appropriateness: tier 1, almost always indicated; tier 2, possibly indicated; and tier 3, rarely indicated.

Persistence of potential ST398 MSSA in outpatient settings among US veterans, 2010-2019.

Novel ST398 methicillin susceptible (MSSA) in the United States was first observed in New York City (20042007); its diffusion across the country resulted in changing treatment options. Utilizing outpatient antimicrobial susceptibility data from the Veterans Health Administration from 2010 to 2019, the spatiotemporal prevalence of potential ST398 MSSA is documented.

Analysis of seasonal variation of antibiotic prescribing for respiratory tract diagnoses in primary care practices.

Objective: To determine antibiotic prescribing appropriateness for respiratory tract diagnoses (RTD) by season.

Design: Retrospective cohort study.

Setting: Primary care practices in a university health system.

Effects of antimicrobial therapy duration and class on risk of antimicrobial-resistant Gram-negative bacillus bloodstream infection in patients with AML.

Background: Antimicrobial-resistant Gram-negative bacilli (ARGNB) bloodstream infection (BSI) has been associated with prior antibiotic exposure among hematologic malignancy patients. The relationships between days of therapy (DOT), antimicrobial class, and ARGNB BSI risk are poorly understood.

Methods: This is a single-center, case-control study of acute myeloid leukemia (AML) patients including 115 cases with ARGNB BSI and 230 matched controls with non-ARGNB BSI between January 1, 2007 and December 31, 2018.

A modified Delphi approach to develop a trial protocol for antibiotic de-escalation in patients with suspected sepsis.

Background: Early administration of antibiotics in sepsis is associated with improved patient outcomes, but safe and generalizable approaches to de-escalate or discontinue antibiotics after suspected sepsis events are unknown.

Methods: We used a modified Delphi approach to identify safety criteria for an opt-out protocol to guide de-escalation or discontinuation of antibiotic therapy after 72 hours in non-ICU patients with suspected sepsis. An expert panel with expertise in antimicrobial stewardship and hospital epidemiology rated 48 unique criteria across 3 electronic survey rating tools.

Evaluation of an Opt-Out Protocol for Antibiotic De-Escalation in Patients With Suspected Sepsis: A Multicenter, Randomized, Controlled Trial.

Background: Sepsis guidelines recommend daily review to de-escalate or stop antibiotics in appropriate patients. This randomized, controlled trial evaluated an opt-out protocol to decrease unnecessary antibiotics in patients with suspected sepsis.

Methods: We evaluated non-intensive care adults on broad-spectrum antibiotics despite negative blood cultures at 10 US hospitals from September 2018 through May 2020.

Unsuspected Clonal Spread of Methicillin-Resistant Staphylococcus aureus Causing Bloodstream Infections in Hospitalized Adults Detected Using Whole Genome Sequencing.

Background: Though detection of transmission clusters of methicillin-resistant Staphylococcus aureus (MRSA) infections is a priority for infection control personnel in hospitals, the transmission dynamics of MRSA among hospitalized patients with bloodstream infections (BSIs) has not been thoroughly studied. Whole genome sequencing (WGS) of MRSA isolates for surveillance is valuable for detecting outbreaks in hospitals, but the bioinformatic approaches used are diverse and difficult to compare.

Methods: We combined short-read WGS with genotypic, phenotypic, and epidemiological characteristics of 106 MRSA BSI isolates collected for routine microbiological diagnosis from inpatients in 2 hospitals over 12 months.

SARS-CoV-2 RNA persists on surfaces following terminal disinfection of COVID-19 hospital isolation rooms.

We evaluated the effect of terminal cleaning on SARS-CoV-2 RNA contamination of COVID-19 isolation rooms in an acute care hospital. SARS-CoV-2 RNA was detected on 32.1% of room surfaces after cleaning; the odds of contamination increased with month.

MRSA surveillance programmes worldwide: moving towards a harmonised international approach.

Multinational surveillance programmes for methicillin-resistant Staphylococcus aureus (MRSA) are dependent on national structures for data collection. This study aimed to capture the diversity of national MRSA surveillance programmes and to propose a framework for harmonisation of MRSA surveillance. The International Society of Antimicrobial Chemotherapy (ISAC) MRSA Working Group conducted a structured survey on MRSA surveillance programmes and organised a webinar to discuss the programmes' strengths and challenges as well as guidelines for harmonisation.

Spatial and temporal effects on severe acute respiratory coronavirus virus 2 (SARS-CoV-2) contamination of the healthcare environment.

Background: The spatial and temporal extent of severe acute respiratory coronavirus virus 2 (SARS-CoV-2) environmental contamination has not been precisely defined. We sought to elucidate contamination of different surface types and how contamination changes over time.

Methods: We sampled surfaces longitudinally within COVID-19 patient rooms, performed quantitative RT-PCR for the detection of SARS-CoV-2 RNA, and modeled distance, time, and severity of illness on the probability of detecting SARS-CoV-2 using a mixed-effects binomial model.

Healthcare microenvironments define multidrug-resistant organism persistence.

Background: Multidrug-resistant organisms (MDROs) colonizing the healthcare environment have been shown to contribute to risk for healthcare-associated infections (HAIs), with adverse effects on patient morbidity and mortality. We sought to determine how bacterial contamination and persistent MDRO colonization of the healthcare environment are related to the position of patients and wastewater sites.

Methods: We performed a prospective cohort study, enrolling 51 hospital rooms at the time of admitting a patient with an eligible MDRO in the prior 30 days.