Use of a penicillin allergy clinical decision rule to enable direct oral penicillin provocation: an international multicentre randomised control trial in an adult population (PALACE): study protocol

INTRODUCTION

Penicillin allergies are highly prevalent in the healthcare setting and associated with the prescription of second-line inferior antibiotics. More than 85% of all penicillin allergy labels can be removed by skin testing and 96%-99% of low-risk penicillin allergy labels can be removed by direct oral challenge. An internally and externally validated clinical assessment tool for penicillin allergy, PEN-FAST, can identify a low-risk penicillin allergy without the need for skin testing; a score of less than 3 has a negative predictive value of 96.3% (95% CI, 94.1 to 97.8) for the presence of a penicillin allergy. It is hypothesised that PEN-FAST is a safe and effective tool for assessing penicillin allergy in an outpatient clinic setting.

METHODS AND ANALYSIS

This is an international, multicentre randomised control trial using the PEN-FAST tool to risk-stratify penicillin allergy labels in adult outpatients. The study's primary objective is to evaluate the non-inferiority of using PEN-FAST score-guided management with direct oral challenge compared with standard care (defined as prick and intradermal skin testing followed by oral penicillin challenge). Participants will be randomised 1:1 to the intervention arm (direct oral penicillin challenge) or standard of care arm (skin testing followed by oral penicillin challenge, if skin testing is negative). The sample size of 380 randomised patients (190 per treatment arm) is required to demonstrate non-inferiority.

ETHICS AND DISSEMINATION

The study will be performed according to the guidelines of the Helsinki Declaration and is approved by the Austin Health Human Research Ethics Committee (HREC/62425/Austin-2020) in Melbourne Australia, Vanderbilt University Institutional Review Board (IRB #202174) in Tennessee, USA, Duke University Institutional Review Board (IRB #Pro00108461) in North Carolina, USA and McGill University Health Centre Research Ethics Board in Canada (PALACE/2022-7605). The results of this study will be published and presented in various scientific forums.

TRIAL REGISTRATION NUMBER

NCT04454229.

Landscape of coronavirus disease 2019 clinical trials: New frontiers and challenges

BACKGROUND/AIM

The number of coronavirus disease 2019 deaths and cases continues to increase globally. Novel therapies are urgently needed to treat patients with coronavirus disease 2019. We sought to provide a critical review of trials designed during the coronavirus disease 2019 pandemic. Our primary goal was to provide a critical review of the landscape of clinical trials designed to address the coronavirus disease 2019 pandemic. Specifically, we were interested in assessing the design of phase II/III and phase III interventional trials.

METHODS

We utilized the ClinicalTrials.gov database to include trials registered between 1 December 2019 and 11 April 2021 to survey the current landscape of clinical trials for coronavirus disease 2019. Variables extracted included: National Clinical Trial number, title, location, sponsor, study type, start date, completion date, gender group, age group, primary outcome, secondary outcome, overall status, and associated references.

RESULTS

About 57% of studies were interventional, 14.5% were phase III trials, and the majority of the therapeutic trials included hospitalized patients. There were 52 primary composite outcomes and 285 unique interventions spanning 10 drug classes. The outcomes, disease severity, and comparators varied substantially across trials, and the trials were often too small to be definitive.

CONCLUSION

These findings are relevant as we strongly advocate for global coordination of efforts through the use of common platforms that enable harmonizing of endpoints, collection of common key variables and clear definition of disease severity to have clinically meaningful results from clinical trials.

Association of Black Race With Physical and Chemical Restraint Use Among Patients Undergoing Emergency Psychiatric Evaluation

OBJECTIVE

Few studies have examined the disproportionate use of restraints for Black adults receiving emergency psychiatric care. This study sought to determine whether the odds of physical and chemical restraint use were higher for Black patients undergoing emergency psychiatric care compared with their White counterparts.

METHODS

This single-center retrospective cohort study examined 12,977 unique encounters of adults receiving an emergency psychiatric evaluation between January 1, 2014, and September 18, 2020, at a large academic medical center in Durham, North Carolina. Self-reported race categories were extracted from the electronic medical record. Primary outcomes were the presence of a behavioral physical restraint order or chemical restraint administration during the emergency department encounter. Covariates included age, sex, ethnicity, height, time of arrival, positive urine drug screen results, peak blood alcohol concentration, and diagnosis of a bipolar or psychotic disorder.

RESULTS

A total of 961 (7.4%) encounters involved physical restraint, and 2,047 (15.8%) involved chemical restraint. Models with and without a race covariate were compared by using quasi-likelihood information criterion scores; in each instance, the model with race performed better than the model without. Black patients were more likely to be physically (adjusted odds ratio [AOR]=1.35; 95% confidence interval [CI]=1.07-1.72) and chemically (AOR=1.33; 95% CI=1.15-1.55) restrained than White patients.

CONCLUSIONS

After analyses were adjusted for measured confounders, Black patients undergoing psychiatric evaluation were at higher odds of experiencing physical or chemical restraint compared with White patients, which is consistent with the growing body of evidence revealing racial disparities in psychiatric care.

Determination of plasma protein binding of dalbavancin

OBJECTIVES

Dalbavancin is a lipoglycopeptide with a long half-life, making it a promising treatment for infections requiring prolonged therapy, such as complicated Staphylococcus aureus bacteraemia. Free drug concentration is a critical consideration with prolonged treatment, since free concentration-time profiles may best correlate with therapeutic effect. In support of future clinical trials, we aimed to develop a reliable and reproducible assay for measuring free dalbavancin concentrations.

METHODS

The ultracentrifugation technique was used to determine free dalbavancin concentrations in plasma at two concentrations (50 and 200 mg/L) in duplicate. Centrifuge tubes and pipette tips were treated for 24 h before use with Tween 80 to assess adsorption. Dalbavancin concentrations were analysed from the plasma samples (total) and middle layer samples (free) by LC/MS/MS with isotopically labelled internal standard. Warfarin served as a positive control with known high protein binding.

RESULTS

Measurement of free dalbavancin was sensitive to adsorption onto plastic. Treatment of tubes and pipette tips with ≥2% Tween 80 effectively prevented drug loss during protein binding experiments. By the ultracentrifugation method, dalbavancin's protein binding was estimated to be approximately 99%.

CONCLUSIONS

Dalbavancin has very high protein binding. Given dalbavancin's high protein binding, accurate measurement of free dalbavancin concentrations should be a key consideration in future exposure-response studies, especially clinical trials. Future investigations should confirm if the active fraction is best predicted by the free or total fraction.

Dalbavancin as an option for treatment of S. aureus bacteremia (DOTS): study protocol for a phase 2b, multicenter, randomized, open-label clinical trial

Background

Staphylococcus aureus bacteremia is a life-threatening infection and leading cause of infective endocarditis, with mortality rates of 15–50%. Treatment typically requires prolonged administration of parenteral therapy, itself associated with high costs and potential catheter-associated complications. Dalbavancin is a lipoglycopeptide with potent activity against Staphylococcus and a long half-life, making it an appealing potential therapy for S. aureus bacteremia without the need for durable central venous access.

Methods

DOTS is a phase 2b, multicenter, randomized, assessor-blinded, superiority, active-controlled, parallel-group trial. The trial will enroll 200 adults diagnosed with complicated S. aureus bacteremia, including definite or possible right-sided infective endocarditis, who have been treated with effective antibiotic therapy for at least 72 h (maximum 10 days) and with subsequent clearance of bacteremia prior to randomization to study treatment. Subjects will be randomized 1:1 to complete their antibiotic treatment course with either two doses of dalbavancin on days 1 and 8, or with a total of 4–8 weeks of standard intravenous antibiotic therapy. The primary objective is to compare the Desirability of Outcome Ranking (DOOR) at day 70 for patients randomized to dalbavancin versus standard of care. Key secondary endpoints include quality of life outcomes and pharmacokinetic analyses of dalbavancin.

Discussion

The DOTS trial will establish whether dalbavancin is superior to standard parenteral antibiotic therapy for the completion of treatment of complicated S. aureus bacteremia.

Trial registration

US National Institutes of Health ClinicalTrials.govNCT04775953. Registered on 1 March 2021

Impact of COVID ‐19 pandemic on pharmacist‐led allergy assessments and penicillin skin testing

Allergy assessments and penicillin skin testing are associated with reductions in high‐Clostridioides difficile infection (CDI)‐risk antibiotic use and lower hospital‐acquired CDI rates; however, these activities require substantial personnel and resource allocation. Recently, many antimicrobial stewardship programs’ (ASPs) focus shifted towards supporting the COVID‐19 pandemic response. We evaluated the impact of the COVID‐19 pandemic on a pharmacist‐led allergy assessment and penicillin skin testing program. Patients undergoing allergy assessment and/or penicillin skin testing (PST) from 1 January 2017 through 30 April 2021 were included for review. Monthly PST and allergy assessment rates were calculated and defined as the number of PSTs or allergy assessments per 1000 unique patient encounters for each month, respectively. The study used interrupted time series regression to assess potential level and slope changes in allergy assessments and PSTs during the pandemic. 200 058 total inpatient encounters by 188 867 unique patients occurred during the study period. ASP performed 918 allergy assessments and 204 PSTs. The local onset of the SARS‐CoV‐2 pandemic during March 2020 was associated with significant level reductions in allergy assessments and PSTs. Additional responsibilities added to the ASP team during the COVID‐19 pandemic limited the ability to perform core antimicrobial stewardship activities with proven patient care benefits.

COVID-19 Trials: Who Participates and Who Benefits?

The coronavirus disease 2019 (COVID-19) pandemic has had a disproportionate impact on older adults and racial and ethnic minority individuals in the United States. This article reviews a COVID-19 therapeutics trial conducted at the authors’ institution to examine the low enrollment of groups particularly vulnerable to COVID-19. They reflect on the potential lack of impact that effective COVID-19 therapeutics may have on mortality if vulnerable groups are not enrolled in trials.

Objectives

The coronavirus disease 2019 (COVID-19) pandemic has disproportionately afflicted vulnerable populations. Older adults, particularly residents of nursing facilities, represent a small percentage of the population but account for 40% of mortality from COVID-19 in the United States. Racial and ethnic minority individuals, particularly Black, Hispanic, and Indigenous Americans have experienced higher rates of infection and death than the White population. Although there has been an unprecedented explosion of clinical trials to examine potential therapies, participation by members of these vulnerable communities is crucial to obtaining data generalizable to those communities.

Methods

We undertook an open-label, factorial randomized clinical trial examining hydroxychloroquine and/or azithromycin for hospitalized patients.

Results

Of 53 screened patients, 11 (21%) were enrolled. Ten percent (3/31) of Black patients were enrolled, 33% (7/21) of White patients, and 50% (6/12) of Hispanic patients. Forty-seven percent (25/53) of patients declined participation despite eligibility; 58%(18/31) of Black patients declined participation. Forty percent (21/53) of screened patients were from a nursing facility and 10% (2/21) were enrolled. Enrolled patients had fewer comorbidities than nonenrolled patients: median modified Charlson comorbidity score 2.0 (interquartile range 0–2.5), versus 4.0 (interquartile range 2–6) for nonenrolled patients (P = 0.006). The limitations of the study were the low participation rate and the multiple treatment trials concurrently recruiting at our institution.

Conclusions

The high rate of nonparticipation in our trial of nursing facility residents and Black people emphasizes the concern that clinical trials for therapeutics may not target key populations with high mortality rates.

Age-Related Changes in the Nasopharyngeal Microbiome Are Associated With Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Infection and Symptoms Among Children, Adolescents, and Young Adults

BACKGROUND

Children are less susceptible to SARS-CoV-2 infection and typically have milder illness courses than adults, but the factors underlying these age-associated differences are not well understood. The upper respiratory microbiome undergoes substantial shifts during childhood and is increasingly recognized to influence host defense against respiratory pathogens. Thus, we sought to identify upper respiratory microbiome features associated with SARS-CoV-2 infection susceptibility and illness severity.

METHODS

We collected clinical data and nasopharyngeal swabs from 285 children, adolescents, and young adults (<21 years) with documented SARS-CoV-2 exposure. We used 16S ribosomal RNA gene sequencing to characterize the nasopharyngeal microbiome and evaluated for age-adjusted associations between microbiome characteristics and SARS-CoV-2 infection status and respiratory symptoms.

RESULTS

Nasopharyngeal microbiome composition varied with age (PERMANOVA, P < .001; R2 = 0.06) and between SARS-CoV-2-infected individuals with and without respiratory symptoms (PERMANOVA, P  = .002; R2 = 0.009). SARS-CoV-2-infected participants with Corynebacterium/Dolosigranulum-dominant microbiome profiles were less likely to have respiratory symptoms than infected participants with other nasopharyngeal microbiome profiles (OR: .38; 95% CI: .18-.81). Using generalized joint attributed modeling, we identified 9 bacterial taxa associated with SARS-CoV-2 infection and 6 taxa differentially abundant among SARS-CoV-2-infected participants with respiratory symptoms; the magnitude of these associations was strongly influenced by age.

CONCLUSIONS

We identified interactive relationships between age and specific nasopharyngeal microbiome features that are associated with SARS-CoV-2 infection susceptibility and symptoms in children, adolescents, and young adults. Our data suggest that the upper respiratory microbiome may be a mechanism by which age influences SARS-CoV-2 susceptibility and illness severity.

The impact of infection vs. colonization on Clostridioides difficile environmental contamination in hospitalized patients with diarrhea

Background

Patients with Clostridioides difficile infections (CDIs) contaminate the healthcare environment; however, the relative contribution of contamination by colonized individuals is unknown. Current guidelines do not recommend the use of contact precautions for asymptomatic C difficile carriers. We evaluated C difficile environmental contamination in rooms housing adult inpatients with diarrhea based on C difficile status.

Methods

We performed a prospective cohort study of inpatient adults with diarrhea who underwent testing for CDI via polymerase chain reaction (PCR) and enzyme immunoassay (EIA). Patients were stratified into cohorts based on test result: infected (PCR⁺/EIA⁺), colonized (PCR⁺/EIA⁻), or negative/control (PCR⁻). Environmental microbiological samples were taken within 24 hours of C difficile testing and again for 2 successive days. Samples were obtained from the patient, bathroom, and care areas.

Results

We enrolled 94 patients between November 2019 and June 2021. Clostridioides difficile was recovered in 93 (38%) patient rooms: 44 (62%) infected patient rooms, 35 (43%) colonized patient rooms (P = .08 vs infected 38 patient rooms), and 14 (15%) negative patient rooms (P < .01 vs infected; P < .01 vs colonized). Clostridioides difficile was recovered in 40 (56%), 6 (9%), and 20 (28%) of bathrooms, care areas and patient areas in 40 infected patient rooms; 34 (41%), 1 (1%), and 4 (5%) samples in colonized patient rooms; and 12 (13%), 1 (1%), and 3 (3%) of samples in negative patient rooms, respectively.

Conclusions

Patients colonized with C difficile frequently contaminated the hospital environment. Our data support the use of contact precautions when entering rooms of patients colonized with C difficile, especially when entering the bathroom.

Impact of Education and Data Feedback on Antibiotic Prescribing for Urinary Tract Infections in the Emergency Department: An Interrupted Time Series Analysis

BACKGROUND

Urinary tract infections (UTIs) are often misdiagnosed or treated with exceedingly broad-spectrum antibiotics, leading to negative downstream effects. We aimed to implement antimicrobial stewardship (AS) strategies targeting UTI prescribing in the emergency department (ED).

METHODS

We conducted a quasi-experimental prospective AS intervention outlining appropriate UTI diagnosis and management across three EDs, within an academic and two community hospitals, in North Carolina, United States. The study was divided into three phases, a baseline period and two intervention phases. Phase 1 included introduction of an ED-specific urine antibiogram and UTI guideline, education, and department-specific feedback on UTI diagnosis and antibiotic prescribing. Phase 2 included re-education and provider-specific feedback. Eligible patients included adults with an antibiotic prescription for UTI diagnosed in the ED from 11/13/18 to 3/1/21. Admitted patients were excluded. The primary outcome was guideline-concordant antibiotic use, assessed using an interrupted time series regression analysis with 2-week intervals.

RESULTS

Overall, 8,742 distinct patients with 10,426 patient encounters were included. Ninety-two percent of all encounters (n=9,583) were diagnosed with cystitis and 8.1% with pyelonephritis (n=843). There was an initial 15% increase in guideline-concordant antibiotic prescribing in Phase 1 compared to the pre-intervention period (incidence rate ratio [IRR] 1.15; 95% confidence interval [CI] 1.03 to 1.29). A significant increase of guideline-concordant prescriptions was seen with every two-week interval during Phase 2 (IRR 1.03; 95% CI 1.01 to 1.04).

CONCLUSIONS

This multifaceted AS intervention involving a guideline, education, and provider-specific feedback increased guideline-concordant antibiotic choices for treat-and-release patients in the ED.

242. Rising Incidence of Finegoldia magna among Prosthetic Joint Infections

Background

Finegoldia magna is an anaerobic, Gram-positive coccus infrequently associated with osteoarticular infections. Since the adoption of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF), F. magna has been increasingly reported as a cause of osteoarticular infections. Our objective was to determine the incidence of F. magna prosthetic joint infections (PJIs) within our institution.

Methods

We conducted a retrospective longitudinal survey from 1 January 2016 - 31 December 2020 at an academic tertiary care referral center. We constructed two Poisson count models to assess the incidence of Finegoldia magna PJIs: one consisting of a clinical microbiology database of synovial fluid and surgical tissue cultures and one using a PJI registry. Time served as the covariate of interest. We used number of cultures as an offset term in the clinical microbiology model, and number of PJI cases as the offset term in the prosthetic joint registry model –reflecting the relevant denominator for each dataset. The microbiology database was limited to synovial fluid aspirates and surgical tissue cultures to minimize risk of confounding by contaminants.

Results

The PJI registry included 44 F. magna infections occurring among 4,706 (0.9%) PJIs. The microbiology survey included 99 F. magna isolates from 43,940 (0.2%) cultures sent from joint aspirates or surgical tissue cultures. Among overall synovial and surgical tissue cultures, we found no significant increase in F. magna over time (incidence rate ratio [IRR] 1.0, 95% CI: 0.9-1.2, Figure 1A). Within the PJI registry, however, we observed a 40% per-year increase in F. magna incidence (IRR 1.4, 95% CI: 1.1-1.8, Figure 1B).

Figure 1

Incidence of Finegoldia magna Over Time

Conclusion

Adoption of MALDI-TOF has expanded the clinical microbiology laboratory’s capacity for rapid speciation, sometimes revealing previously unseen epidemiologic trends. While we saw no significant change in overall incidence of F. magna among synovial and surgical tissue cultures, we did detect a significant increase specifically among PJI cases. F. magna warrants attention as an emerging pathogen among PJI.

Disclosures

All Authors: No reported disclosures

1094. Determination of Plasma Protein Binding of Dalbavancin

Background

Dalbavancin is a semi-synthetic glycopeptide with a long half-life, making it a promising alternative for infections requiring prolonged therapy such as complicated Staphylococcus aureus bacteremia. A critical pharmacokinetic consideration with prolonged treatment is the unbound or “free” concentration-time profile, as free antibiotic concentrations may correlate with tissue penetration and therapeutic effects better than total drug. Dalbavancin’s plasma protein binding (PB) remains poorly studied and has been reported to range between 93-99%. A reliable and validated free drug assay is needed to link dalbavancin concentrations with patient outcomes.

Methods

The ultracentrifugation technique was used to determine free dalbavancin concentrations in plasma at two concentrations (50 and 200 µg/mL) in duplicate. Centrifuge tubes and pipette tips were treated for 24 hours before use with Tween 80 to assess adsorption. PB centrifugation conditions: 400,000 g (106,000 RPM in TLA-120.1 rotor) for 4 hours at 37°C. Dalbavancin concentrations were analyzed from the plasma samples (total) and middle layer samples (free) by liquid chromatography – tandem mass spectrometry (LC/MS/MS) with isotopically labeled internal standard. Warfarin served as a positive control with known high protein binding.

Results

Measurement of free dalbavancin was sensitive to adsorption onto plastic. Treatment of tubes and pipette tips with ≥2% Tween 80 effectively prevented drug loss during PB experiments (Figure 1). Addition of 2% Tween 80 did not affect PB results of warfarin. In PB experiments with 2% Tween 80 coated tubes, the free fraction of dalbavancin was 0.96% (95% CI: 0.94-0.98) at 50 µg/mL and 1.11% (95% CI: 1.08-1.13) at 200 µg/mL.

Figure 1. Percent Free Dalbavancin vs Varying Concentrations of Tween 80 for Pretreatment of Tubes

Conclusion

By the ultracentrifugation method, dalbavancin’s PB was estimated to be approximately 99%. Given dalbavancin’s high PB, accurate measurement of free dalbavancin concentrations should be a key consideration in future exposure-response studies, especially clinical trials. Future investigations should also determine if the active fraction is best predicted by the free or total fraction, as this remains a subject of debate.

Supported by NIAID/NIH grant UM1AI104681. Content is solely the authors’ responsibility and does not represent official NIH views.

Disclosures

Thomas L. Holland, MD, Aridis (Consultant)Basilea Pharmaceutica (Consultant)Lysovant (Consultant) Thomas L. Holland, MD, Aridis (Individual(s) Involved: Self): Consultant; Basilea Pharmaceutica (Individual(s) Involved: Self): blinded adjudication, Consultant, Other Financial or Material Support; Genentech (Individual(s) Involved: Self): Consultant; Lysovant (Individual(s) Involved: Self): Consultant; Motif Bio (Individual(s) Involved: Self): Consultant Thomas Lodise, Jr., PharmD, PhD, Astra-Zeneca (Consultant)Bayer (Consultant)DoseMe (Consultant, Advisor or Review Panel member)ferring (Consultant)genentech (Consultant)GSK (Consultant)Melinta (Consultant)merck (Consultant, Independent Contractor)nabriva (Consultant)paratek (Consultant, Advisor or Review Panel member, Speaker’s Bureau)shionogi (Consultant, Advisor or Review Panel member, Speaker’s Bureau)Spero (Consultant)tetraphase (Consultant)Venatrox (Consultant) Thomas Lodise, Jr., PharmD, PhD, Melinta Therapeutics (Individual(s) Involved: Self): Consultant; Merck (Individual(s) Involved: Self): Consultant, Scientific Research Study Investigator; Paratek (Individual(s) Involved: Self): Consultant; Shionogi (Individual(s) Involved: Self): Consultant, Speakers’ bureau; Spero (Individual(s) Involved: Self): Consultant; Tetraphase Pharmaceuticals Inc. (Individual(s) Involved: Self): Consultant

Severe Acute Respiratory Syndrome Coronavirus 2 Infections Among Children in the Biospecimens from Respiratory Virus-Exposed Kids (BRAVE Kids) Study

BACKGROUND

Child with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection typically have mild symptoms that do not require medical attention, leaving a gap in our understanding of the spectrum of SARS-CoV-2-related illnesses that the viruses causes in children.

METHODS

We conducted a prospective cohort study of children and adolescents (aged <21 years) with a SARS-CoV-2-infected close contact. We collected nasopharyngeal or nasal swabs at enrollment and tested for SARS-CoV-2 using a real-time polymerase chain reaction assay.

RESULTS

Of 382 children, 293 (77%) were SARS-CoV-2-infected. SARS-CoV-2-infected children were more likely to be Hispanic (P < .0001), less likely to have asthma (P = .005), and more likely to have an infected sibling contact (P = .001) than uninfected children. Children aged 6-13 years were frequently asymptomatic (39%) and had respiratory symptoms less often than younger children (29% vs 48%; P = .01) or adolescents (29% vs 60%; P < .001). Compared with children aged 6-13 years, adolescents more frequently reported influenza-like (61% vs 39%; P < .001) , and gastrointestinal (27% vs 9%; P = .002), and sensory symptoms (42% vs 9%; P < .0001) and had more prolonged illnesses (median [interquartile range] duration: 7 [4-12] vs 4 [3-8] days; P = 0.01). Despite the age-related variability in symptoms, wWe found no difference in nasopharyngeal viral load by age or between symptomatic and asymptomatic children.

CONCLUSIONS

Hispanic ethnicity and an infected sibling close contact are associated with increased SARS-CoV-2 infection risk among children, while asthma is associated with decreased risk. Age-related differences in clinical manifestations of SARS-CoV-2 infection must be considered when evaluating children for coronavirus disease 2019 and in developing screening strategies for schools and childcare settings.

Asymptomatic or mild symptomatic SARS-CoV-2 infection elicits durable neutralizing antibody responses in children and adolescents

As SARS-CoV-2 continues to spread globally, questions have emerged regarding the strength and durability of immune responses in specific populations. In this study, we evaluated humoral immune responses in 69 children and adolescents with asymptomatic or mild symptomatic SARS-CoV-2 infection. We detected robust IgM, IgG, and IgA antibody responses to a broad array of SARS-CoV-2 antigens at the time of acute infection and 2 and 4 months after acute infection in all participants. Notably, these antibody responses were associated with virus-neutralizing activity that was still detectable 4 months after acute infection in 94% of children. Moreover, antibody responses and neutralizing activity in sera from children and adolescents were comparable or superior to those observed in sera from 24 adults with mild symptomatic infection. Taken together, these findings indicate that children and adolescents with mild or asymptomatic SARS-CoV-2 infection generate robust and durable humoral immune responses that can likely contribute to protection from reinfection.

Impact of Antibiotic Stewardship Rounds in the Intensive Care Setting: a prospective cluster-randomized crossover study

BACKGROUND

Few groups have formally studied the effect of dedicated antibiotic stewardship rounds (ASRs) on antibiotic use (AU) in intensive care units (ICUs).

METHODS

We implemented weekly ASRs using a two-arm, cluster-randomized, crossover study in 5 ICUs at Duke University Hospital from 11/2017 to 6/2018. We excluded patients without an active antibiotic order, or if they had a marker of high complexity including an existing infectious disease consult, transplant, ventricular assist device, or ECMO. AU during and following ICU stay for patients with ASRs was compared to the controls. We recorded the number of reviews, recommendations delivered, and responses. We evaluated change in ICU-specific AU during and after the study.

RESULTS

Our analysis included 4,683 patients: 2330 intervention and 2353 controls. Teams performed 761 reviews during ASRs, which excluded 1569 patients: 60% of patients off antibiotics, and 8% complex patients. Exclusions affected 88% the cardiac surgery ICU (CTICU) patients. AU rate ratio (RR) was 0.97 (0.91-1.04). When CTICU was removed, the RR was 0.93 (0.89-0.98). AU in the post-study period decreased by 16% (95% CI 11-24%) compared to the AU in the baseline period. Change in AU was differential among units: largest in the neurology ICU (-28%) and smallest in the CTICU (-2%).

CONCLUSION

Weekly multi-disciplinary ASRs was a high-resource intervention associated with a small AU reduction. The noticeable ICU AU decline over time is possibly due to indirect effects of ASRs. Effects differed among specialty ICUs, emphasizing the importance of customizing ASRs to match unit-specific population, workflow, and culture.

A Cluster of Nontuberculous Mycobacterial Tenosynovitis Following Hurricane Relief Efforts

BACKGROUND

Nontuberculous mycobacteria (NTM) are a rare cause of infectious tenosynovitis of the upper extremity. Using molecular methods, clinical microbiology laboratories are increasingly reporting identification down to the species level. Improved methods for speciation are revealing new insights into the clinical and epidemiologic features of rare NTM infections.

METHODS

We encountered 3 cases of epidemiologically linked upper extremity NTM tenosynovitis associated with exposure to hurricane-damaged wood. We conducted whole-genome sequencing to assess isolate relatedness followed by a literature review of NTM infections that involved the upper extremity.

RESULTS

Despite shared epidemiologic risk, the cases were caused by 3 distinct organisms. Two cases were rare infections caused by closely related but distinct species within the Mycobacterium terrae complex that could not be differentiated by traditional methods. The third case was caused by Mycobacterium intracellulare. An updated literature review that focused on research that used modern molecular speciation methods found that several species within the M. terrae complex are increasingly reported as a cause of upper extremity tenosynovitis, often in association with environmental exposures.

CONCLUSIONS

These cases illustrate the importance of molecular methods for speciating phenotypically similar NTM, as well as the limitations of laboratory-based surveillance in detecting point-source outbreaks when the source is environmental and may involve multiple organisms.

Impact of Oral Metronidazole, Vancomycin, and Fidaxomicin on Host Shedding and Environmental Contamination with Clostridioides difficile

OBJECTIVES

Shedding of Clostridioides difficile spores from infected individuals contaminates the hospital environment and contributes to infection transmission. We assessed whether antibiotic selection impacts C. difficile shedding and contamination of the hospital environment.

METHODS

In this prospective, unblinded, randomized controlled trial of hospitalized adults with C. difficile infection, subjects were randomized 1:1:1 to receive fidaxomicin, oral vancomycin, or metronidazole. The primary outcome was change in environmental contamination rate while on treatment. Secondary outcomes included stool shedding, total burden of contamination, and molecular relatedness of stool versus environmental C. difficile isolates.

RESULTS

33 patients were enrolled and 31 (94%) completed the study. Fidaxomicin (-0.36 log10 CFU/day, 95% CI -0.52 to -0.19, p<0.01) and vancomycin (-0.17 log10 CFU/day, 95% CI -0.34 to -0.01, p=0.05) were associated with more rapid decline in C. difficile shedding compared to metronidazole (-0.01 log10 CFU/day, 95% CI -0.10 to +0.08). Both vancomycin (6.3%, 95% CI 4.7-8.3%) and fidaxomicin (13.1%, 95% CI 10.7-15.9%) were associated with lower rates of environmental contamination than metronidazole (21.4%, 95% CI 18.0-25.2%). When specifically modeling within-subject change over time, fidaxomicin (aOR 0.83, 95% CI 0.70-0.99, p=0.04) was associated with more rapid decline in environmental contamination than vancomycin or metronidazole. Overall, 207 of 233 (88.8%) of environmental C. difficile isolates matched subject stool isolates by ribotyping, without significant difference by treatment.

CONCLUSIONS

Fidaxomicin, and to a lesser extent vancomycin, reduces C. difficile shedding and contamination of the hospital environment relative to metronidazole. Treatment choice may play a role in reducing healthcare-associated C. difficile transmission.

Social Disadvantage, Politics, and Severe Acute Respiratory Syndrome Coronavirus 2 Trends: A County-level Analysis of United States Data

Background

Understanding the epidemiology of SARS-CoV-2 is essential for public health control efforts. Social, demographic, and political characteristics at the US county level might be associated with changes in SARS-CoV-2 case incidence.

Methods

We conducted a retrospective analysis of the relationship between the change in reported SARS-CoV-2 case counts at the US county level during June 1, 2020 – June 30,2020 and social, demographic, and political characteristics of the county.

Results

1023/3142 US counties were included in the analysis. 678 (66·3%) had increasing, and 345 (33·7%) had non-increasing SARS-CoV-2 case counts between June 1 – June 30, 2020. In bivariate analysis, counties with increasing case counts had significantly higher Social Deprivation Index (median 48, IQR 24 – 72) than counties with non-increasing case counts (median 40, IQR 19 – 66; p=0·009). Counties with increasing case counts were significantly more likely to be metropolitan areas of 250,000 – 1 million population (p&0·001), to have a higher percentage of Black residents (9% vs. 6%, p=0·013), and to have voted for the Republican presidential candidate in 2016 by a 10-point or greater margin (p=0·044). In the multivariable model, metropolitan areas of 250,000 – 1 million population, higher percentage of Black residents and a 10-point or greater Republican victory were independently associated with increasing case counts.

Conclusions

Increasing case counts of SARS-CoV-2 in the US during June 2020 were associated with a combination of sociodemographic and political factors. Addressing social disadvantage and differential belief systems that may correspond with political alignment will play a critical role in pandemic control.

Evaluation of a Pharmacist-Led Penicillin Allergy Assessment Program and Allergy Delabeling in a Tertiary Care Hospital

IMPORTANCE

Penicillin allergies are frequently mislabeled, which may contribute to use of less-preferred alternative antibiotics.

OBJECTIVE

To evaluate a pharmacist-led allergy assessment program's association with antimicrobial use and clinical outcomes.

DESIGN, SETTING, AND PARTICIPANTS

A pharmacist-led allergy assessment program was launched in 2 phases (June 1, 2015, and November 2, 2016) at a single-center tertiary referral hospital. The longitudinal cross-sectional study included all study period adult admissions; hospitalwide outcomes were assessed by segmented regression. Individual outcomes were assessed within an embedded propensity score-matched case-control study of inpatients undergoing comprehensive allergy assessment following self-report of penicillin allergy. Analysis occurred from March 1, 2020, to February 29, 2020.

EXPOSURES

The longitudinal study analyzed hospital-level outcomes over 3 periods: preintervention (15 months), phase 1 (structured allergy history alone, 16 months), and phase 2 (comprehensive assessment including penicillin skin testing, 52 months). The case-control study defined cases as individuals undergoing comprehensive allergy assessment.

MAIN OUTCOMES AND MEASURES

Hospital-level outcomes included antibiotic days of therapy per 1000 patient-days and hospital-acquired Clostridioides difficile infection (CDI) incidence per 10 000 patient-days. Individual outcomes included antibiotic selection, overall survival, and CDI-free survival.

RESULTS

Longitudinal analysis spanned 2014-2020 (median admissions, 46 416 per year; interquartile range [IQR], 46 001-50 091 per year). Hospitalwide, allergy histories were temporally associated with decreased use of nonpenicillin alternative antibiotics (rate ratio, 0.87; 95% CI, 0.79-0.97) and high-CDI-risk antibiotics (rate ratio, 0.91; 95% CI, 0.85-0.98). Penicillin skin testing was temporally associated with lower hospital-acquired CDI rates (rate ratio, 0.61; 95% CI, 0.43-0.86). The embedded case-control study included 272 cases and 819 controls. Median age was 63 years (interquartile range, 51-73 years), 553 (50.7%) patients were women, and 229 (21.0%) patients were Black. Allergy-assessed patients were less likely to receive high-CDI-risk antibiotics at discharge (odds ratio, 0.66; 95% CI, 0.44-0.98). Estimated reductions in mortality (hazard ratio, 0.77; 95% CI, 0.55-1.07) and hospital-acquired CDI risk (hazard ratio, 0.53; 95% CI, 0.18-1.55) were not statistically significant.

CONCLUSIONS AND RELEVANCE

Pharmacist-led allergy assessments may be associated with reduced high-CDI-risk antibiotic use at both hospitalwide and individual levels. Although individual reductions in mortality and CDI risk did not achieve significance, divergence of survival curves suggest longer-term benefits of allergy delabeling warrant future study.

Asymptomatic or mild symptomatic SARS-CoV-2 infection elicits durable neutralizing antibody responses in children and adolescents

As SARS-CoV-2 continues to spread globally, questions have emerged regarding the strength and durability of immune responses in specific populations. In this study, we evaluated humoral immune responses in 69 children and adolescents with asymptomatic or mild symptomatic SARS-CoV-2 infection. We detected robust IgM, IgG, and IgA antibody responses to a broad array of SARS-CoV-2 antigens at the time of acute infection and 2 and 4 months after acute infection in all participants. Notably, these antibody responses were associated with virus neutralizing activity that was still detectable 4 months after acute infection in 94% of children. Moreover, antibody responses and neutralizing activity in sera from children and adolescents were comparable or superior to those observed in sera from 24 adults with mild symptomatic infection. Taken together, these findings indicate children and adolescents with mild or asymptomatic SARS-CoV-2 infection generate robust and durable humoral immune responses that are likely to protect from reinfection.

Mortality outcomes with hydroxychloroquine and chloroquine in COVID-19 from an international collaborative meta-analysis of randomized trials

Substantial COVID-19 research investment has been allocated to randomized clinical trials (RCTs) on hydroxychloroquine/chloroquine, which currently face recruitment challenges or early discontinuation. We aim to estimate the effects of hydroxychloroquine and chloroquine on survival in COVID-19 from all currently available RCT evidence, published and unpublished. We present a rapid meta-analysis of ongoing, completed, or discontinued RCTs on hydroxychloroquine or chloroquine treatment for any COVID-19 patients (protocol: https://osf.io/QESV4/ ). We systematically identified unpublished RCTs (ClinicalTrials.gov, WHO International Clinical Trials Registry Platform, Cochrane COVID-registry up to June 11, 2020), and published RCTs (PubMed, medRxiv and bioRxiv up to October 16, 2020). All-cause mortality has been extracted (publications/preprints) or requested from investigators and combined in random-effects meta-analyses, calculating odds ratios (ORs) with 95% confidence intervals (CIs), separately for hydroxychloroquine and chloroquine. Prespecified subgroup analyses include patient setting, diagnostic confirmation, control type, and publication status. Sixty-three trials were potentially eligible. We included 14 unpublished trials (1308 patients) and 14 publications/preprints (9011 patients). Results for hydroxychloroquine are dominated by RECOVERY and WHO SOLIDARITY, two highly pragmatic trials, which employed relatively high doses and included 4716 and 1853 patients, respectively (67% of the total sample size). The combined OR on all-cause mortality for hydroxychloroquine is 1.11 (95% CI: 1.02, 1.20; I² = 0%; 26 trials; 10,012 patients) and for chloroquine 1.77 (95%CI: 0.15, 21.13, I² = 0%; 4 trials; 307 patients). We identified no subgroup effects. We found that treatment with hydroxychloroquine is associated with increased mortality in COVID-19 patients, and there is no benefit of chloroquine. Findings have unclear generalizability to outpatients, children, pregnant women, and people with comorbidities.

Age-related changes in the upper respiratory microbiome are associated with SARS-CoV-2 susceptibility and illness severity

Children are less susceptible to SARS-CoV-2 and typically have milder illness courses than adults. We studied the nasopharyngeal microbiomes of 274 children, adolescents, and young adults with SARS-CoV-2 exposure using 16S rRNA gene sequencing. We find that higher abundances of Corynebacterium species are associated with SARS-CoV-2 infection and SARS-CoV-2-associated respiratory symptoms, while higher abundances of Dolosigranulum pigrum are present in SARS-CoV-2-infected individuals without respiratory symptoms. We also demonstrate that the abundances of these bacteria are strongly, and independently, associated with age, suggesting that the nasopharyngeal microbiome may be a potentially modifiable mechanism by which age influences SARS-CoV-2 susceptibility and severity.

SUMMARY

Evaluation of nasopharyngeal microbiome profiles in children, adolescents, and young adults with a SARS-CoV-2-infected close contact identified specific bacterial species that vary in abundance with age and are associated with SARS-CoV-2 susceptibility and the presence of SARS-CoV-2-associated respiratory symptoms.

45. Antimicrobial Stewardship for Urinary Tract Infection in Three Emergency Departments Across a Health System

Background

Broad spectrum antibiotics are often prescribed to patients presenting to the emergency department (ED) for evaluation of urinary tract infection and pyelonephritis (UTI). We evaluated the effect of a target-specific antibiogram, education, and feedback on UTI diagnosis and antibiotic prescribing in this setting.

Methods

We created a urine-specific antibiogram from patients seen and treated without admission at three ED locations (one academic and two community hospitals). We then provided a treatment algorithm and supplemental educational content to ED providers in November 2019. Educational content highlighted appropriate diagnosis, antibiotic selection, and treatment duration for UTI. Adult encounters with appropriate ICD-9/10 codes within twelve months prior to content delivery comprised the preintervention cohort. The postintervention cohort consisted of adult visits following educational intervention until April 17, 2020. During the postintervention phase (November 2019 to April 2020), summary data regarding UTI diagnoses and guideline-concordant prescriptions were fed back routinely to ED providers through email. Guideline-concordant prescriptions were defined as those adhering to first or second-line therapy in the treatment algorithm. The proportion of prescriptions meeting this definition fulfilled the primary outcome. An interrupted time series analysis measured changes in guideline concordance.

Results

Data from 6,713 distinct encounters were analyzed across the three sites. While guideline concordant prescribing increased following intervention at all locations (30.9% to 38.8%, 48.1% to 49.1%, and 48.2% to 59.6%), these increases were not statistically significant (Figures 1, 2, and 3). The proportion of all ED encounters with a UTI diagnosis did not differ following the intervention. Interestingly, guideline concordance was greater in the academic ED, compared to the community hospitals.

Conclusion

Although guideline concordant prescribing for UTI increased in all three ED settings with education and email correspondence feedback, these results were not statistically significant. A variety of methods may be required to realize improved antibiotic prescribing across a diverse group of clinicians.

Disclosures

Rebekah W. Moehring, MD, MPH, Agency for Healthcare Quality and Research (Grant/Research Support)Centers for Disease Control and Prevention (Grant/Research Support)

799. Mini Root Cause Analysis Reveals Opportunities for Reducing Clostridioides difficile Infection Rates

Background

C. difficile remains the single most common pathogen among healthcare-associated infections. We conducted a multi-center, prospective study using on-site, near real-time root cause analyses to identify opportunities for reducing hospital-onset C. difficile infection rates (HO-CID).

Methods

This prospective cohort study enrolled inpatients with HO-CDI admitted to one of 20 participating hospitals in the southeastern United States from July 2019 to June 2020. For each HO-CDI case, mini root cause analyses were conducted by on-site physicians, infection preventionists, or stewardship pharmacists to assess appropriateness of C. difficile testing and inpatient antibiotic use from the 30 days preceding HO-CDI diagnosis.

Results

The cohort captured 554 total HO-CDI cases and 956 antibiotic use events. 147 (26.5%) of HO-CDI cases were adjudicated as likely inappropriate and a further 51 (9.2%) as potentially inappropriate. Among inappropriately tested cases, 103 (52.0%) had received either laxatives or tube feeds in the preceding 48 hours. 132 (13.8%) of antibiotic use events were identified as potentially inappropriate. Among potentially inappropriate antibiotic use events, 40 (30.3%) received unnecessarily broad-spectrum antibiotics, 20 (15.2%) lacked a confirmed infectious diagnosis, and 4 (3.0%) received a longer than guideline-recommended duration. Risk of inappropriate antibiotic use varied by infection type, with treatment of urinary tract infection being associated with the highest risk of inappropriate antibiotic use (table 1).

Table 1: Relative Risk of Inappropriate Antibiotic Use by Indication

Conclusion

Mini root cause analyses may be a helpful tool for identifying -specific opportunities to reduce HO-CDI rates. We found a high rate of inappropriate testing, usually related to alternative causes for diarrhea such as laxative receipt or tube feeds. While rates of inappropriate antibiotic use were lower than has been reported elsewhere, the majority of opportunities for improvement related to overly broad-spectrum coverage. Urinary tract infections were most strongly associated with inappropriate antibiotic use preceding HO-CDI.

Disclosures

All Authors: No reported disclosures