Assessing the Predictive Value of Methicillin-Resistant Staphylococcus aureus Nares Colonization Among Transplant Recipients and Patients With Neutropenia.

Background: Methicillin-resistant Staphylococcus aureus (MRSA) nares screening has been shown to be a powerful antibiotic stewardship tool for MRSA infections within 7 days of screening across a variety of anatomical locations given the high negative predictive value (NPV). However, the utility outside of 7 days and among transplant recipients and patients with neutropenia is less clear. Methods: This was a retrospective cohort study across Veterans Affairs medical centers in the United States from 1 January 2007 to 1 January 2023 of patients tested for MRSA colonization and who had a subsequent positive bacterial culture within 28 days of MRSA sc---reening. Sensitivity, specificity, positive predictive value, and NPV were calculated across different time points and anatomical culture locations. Results: The cohort consisted of 686 174 patients, 6 277 437 MRSA nares tests, and 2 446 766 positive bacterial cultures within 28 days of MRSA testing. The NPV of MRSA nares screening for ruling out a MRSA infection within 28 days was 95.8% across all anatomical culture sites. The NPV was 97.9% among patients with neutropenia and 97.5% in solid organ and hemopoietic stem cell transplant recipients. Conclusions: MRSA nares screening can reliably be used for de-escalation of anti-MRSA therapy within 28 days of bacterial culture for all patients, including solid organ and hematopoietic transplant recipients and patients with neutropenia.

Minimizing risk while maximizing opportunity: The infectious disease organ offer process survey.

BACKGROUND: The purpose of this study was to understand how transplant infectious disease (TID) physicians assess a potential donor with known or suspected infection and describe posttransplant management. METHODS: We designed a survey of 10 organ offer scenarios and asked questions pertaining to organ acceptability for transplantation and management posttransplant. The survey was distributed to TID clinicians via transplant society listservs and email. Responses were recorded in REDCap, and descriptive statistics were employed. RESULTS: One hundred thirteen infectious disease physicians responded to the survey, of whom 85 completed all cases. Respondents were generally in agreement regarding organ acceptability, although some divergence was seen when evaluating lungs from donors with influenza, tuberculosis, or multidrug-resistant Acinetobacter infection. Posttransplant management showed more variation. Areas of optimization were identified: (1) Further understanding of where risk-mitigation strategies within the donor offer process may improve donor acceptability and therefore organ utilization; (2) importance of recipient considerations in assessing degree of infectious risk; and (3) gaps in evidenced-based data regarding optimal posttransplant management of recipients. CONCLUSION: Evaluation of donor offers by TID clinicians is a complex process. Although the survey does not itself serve to make recommendations regarding best practices, it highlights areas where generation of data to inform acceptance and management practices may allow for improved organ utilization and recipient management.

Optimizing Antimicrobial Stewardship in the Emergency Department.

Antibiotic stewardship is a core component of emergency department (ED) practice and impacts patient safety, clinical outcomes, and public health. The unique characteristics of ED practice, including crowding, time pressure, and diagnostic uncertainty, need to be considered when implementing antibiotic stewardship interventions in this setting. Rapid advances in pathogen detection and host response biomarkers promise to revolutionize the diagnosis of infectious diseases in the ED, but such tests are not yet considered standard of care. Presently, clinical decision support embedded in the electronic health record and pharmacist-led interventions are the most effective ways to improve antibiotic prescribing in the ED.

Evaluation of Antibiotic Allergy in the Ambulatory Setting Using a Standardized Questionnaire.

Patients are sometimes mislabeled as having an immune-mediated antibiotic allergy in their medical records. Therefore, the aim of this study was to investigate the prevalence of subjects with non-immune mediated reactions to antibiotics using a standardized questionnaire. Subjects aged 18 years and older with a documented antibiotic allergy were identified and recruited from 2 outpatient clinics in the greater Chicago area. Subjects completed a standardized questionnaire during a single visit regarding their previous adverse reaction to an antibiotic. For subjects with multiple documented antibiotic allergies, 1 questionnaire was filled out for each antibiotic allergy. Investigators subsequently evaluated the questionnaire responses to determine whether the adverse reaction was a true immune-mediated allergic reaction or an adverse drug reaction. A total of 98 subjects were recruited with completion of 159 questionnaires. Eighteen subjects (18.37%, 95% CI: 10.7%, 26.3%) had antibiotic allergy labels with no corresponding immune-mediated reaction history. There were 35 allergy labels (22.0%, 95% CI: 14.7%, 29.4%) that were unlikely to be immune-mediated. Antibiotics with the highest percentage of clinical histories that were unlikely to be immune-mediated were macrolides (8 of 11 subjects), nitrofurantoin (1 of 2 subjects), and amoxicillin/clavulanate (2 of 8 subjects). The most common antibiotic allergy labels were penicillin (43 of 159 subjects), sulfonamides (25 of 159 subjects), and fluoroquinolones (21 of 159 subjects). Identification of adverse reactions to antibiotics that are unlikely to be immune-mediated can be accomplished using a standardized questionnaire in the outpatient setting. Improved identification of low-risk antibiotic allergy labels can guide de-labeling initiatives to improve antibiotic prescribing.

Antimicrobial Stewardship Techniques for Critically Ill Patients with Pneumonia.

Pneumonia is common in the intensive care unit (ICU), infecting 27% of all critically ill patients. Given the high prevalence of this disease state in the ICU, optimizing antimicrobial therapy while minimizing toxicities is of utmost importance. Inappropriate antimicrobial use can increase the risk of antimicrobial resistance, Clostridiodes difficile infection, allergic reaction, and other complications from antimicrobial use (e.g., QTc prolongation, thrombocytopenia). This review article aims to discuss methods to optimize antimicrobial treatment in patients with pneumonia, including the following: procalcitonin use, utilization of methicillin-resistant Staphylococcus aureus nares testing to determine need for vancomycin therapy, utilization of the Biofire® FilmArray® pneumonia polymerase chain reaction (PCR), and microbiology reporting techniques.

Disseminated Protothecosis Due to Prototheca zopfii and Literature Review.

ABSTRACT: Prototheca species are achlorophyllic algae that are a rare cause of infection in humans. It most commonly causes localized cutaneous disease and rarely disseminated infection. Immunocompromised patients have the highest risk of disseminated protothecosis, with a higher mortality rate than localized cutaneous infections. At the species level, infections caused by Prototheca zopfii are reported less frequently than those caused by Prototheca wickerhamii. The diagnosis can be made using histopathology, culture, and molecular testing. There is no definitive evidence for an effective treatment, which currently consists of antifungals (primarily amphotericin B). With only a handful of cases of disseminated protothecosis reported worldwide that are caused by P. zopfii , we herein present an additional case of a postbone marrow transplant patient in the Midwest of the United States.

In vitro susceptibility of carbapenem resistant Enterobacterales to meropenem-vaborbactam and ceftazidime-avibactam at a single academic medical centre.

BACKGROUND: Carbapenem-resistant Enterobacterales (CRE) are considered an urgent threat. Ceftazidime-avibactam and meropenem-vaborbactam contain ß-lactamase inhibitors active against CRE isolates including those that produce Klebsiella pneumoniae carbapenemases (KPC). METHODS: Retrospective chart review of CRE isolates from 1 January 2016 to 1 November 2018. Collected data includes a descriptive overview of measured MIC values, resistance mechanism via a polymerase chain reaction test (Xpert Carba-R, Cepheid, Sunnyvale CA), as well as clinical outcomes. RESULTS: Of 106 isolates reviewed, 86 isolates met the inclusion criteria from 85 individual subjects. The breakpoint:MIC ratio for ceftazidime-avibactam overall was 4, while for meropenem-vaborbactam this ratio was 32 (p < 0.0001). For KPC isolates, ceftazidime-avibactam MIC50/MIC90 in 2016, 2017, and 2018 were 2/4 mg/L (n = 32), 2/4 mg/L (n = 17), and 2/8 mg/L (n = 30), respectively. The meropenem-vaborbactam MIC50/MIC90, for KPC isolates in 2016, 2017, and 2018 were 0.06/0.125 mg/L (n = 32), 0.06/0.1 mg/L (n = 17), and 0.06/0.5 mg/L (n = 30), respectively. Microbiologic cure was 75% (n = 16) in ceftazidime-avibactam subjects and 58.3% (n = 12) in subjects treated with alternative agents (p = 0.43). The 14- and 30-day mortality was numerically higher in subjects treated with alternate agents when compared ceftazidime-avibactam 2/9 (22.2%) vs 3/17 (17.6%) (p = 1.00) and 4/9 (44.4%) vs 4/17 (28.6%) (p = 0.38), respectively. For ceftazidime-avibactam, 30-day mortality in 2016, 2017, and 2018 was 0/5 (0%), 0/2 (0%), and 4/10 (40%). CONCLUSION: Selective pressure from the use of ceftazidime-avibactam at our institution may be decreasing its utility as a first-line agent for CRE infections. Meropenem-vaborbactam maintained low MIC values and may be a promising treatment option for CRE.

Infectious Disease Consults of Pseudomonas aeruginosa Bloodstream Infection and Impact on Health Outcomes.

Background: Infectious diseases (ID) consultation improves health outcomes for certain infections but has not been well described for Pseudomonas aeruginosa (PA) bloodstream infection (BSI). Therefore, the goal of this study was to examine ID consultation of inpatients with PA BSI and factors impacting outcomes. Methods: This was a retrospective cohort study from January 1, 2012, to December 31, 2018, of adult hospitalized veterans with PA BSI and antibiotic treatment 2 days before through 5 days after the culture date. Multidrug-resistant (MDR) cultures were defined as cultures with resistance to at least 1 agent in ≥3 antimicrobial categories tested. Multivariable logistic regression models were fit to assess the impact of ID consults and adequate treatment on mortality. Results: A total of 3256 patients had PA BSI, of whom 367 (11.3%) were multidrug resistant (MDR). Most were male (97.5%), over 65 years old (71.2%), and White (70.9%). Nearly one-fourth (n = 784, 23.3%) died during hospitalization, and 870 (25.8%) died within 30 days of their culture. Adjusted models showed that ID consultation was associated with decreased in-hospital (odds ratio [OR], 0.47; 95% CI, 0.39-0.56) and 30-day mortality (OR, 0.51; 95% CI, 0.42-0.62). Conclusions: Consultation with ID physicians improves clinical outcomes such as in-hospital and 30-day mortality for patients with PA BSI. ID consultation provides value and should be considered for patients with PA BSI.

Introducing antimicrobial stewardship to the outpatient clinics of a suburban academic health system.

Objective: To establish an antimicrobial stewardship program in the outpatient setting. Design: Prescribers of antimicrobials were asked to complete a survey regarding antimicrobial stewardship. We also monitored their compliance with appropriate prescribing practices, which were shared in monthly quality improvement reports. Setting: The study was performed at Loyola University Health System, an academic teaching healthcare system in a metropolitan suburban environment. Participants: Prescribers of antimicrobials across 19 primary care and 3 immediate- and urgent-care clinics. Methods: The voluntary survey was developed using SurveyMonkeyand was distributed via e-mail. Data were collected anonymously. Rates of compliance with appropriate prescribing practices were abstracted from electronic health records and assessed by 3 metrics: (1) avoidance of antibiotics in adult acute bronchitis and appropriate antibiotic treatment in (2) patients tested for pharyngitis and (3) children with upper respiratory tract infections. Results: Prescribers were highly knowledgeable about what constitutes appropriate prescribing; verified compliance rates were highly concordant with self-reported rates. Nearly all prescribers were concerned about resistance, but fewer than half believed antibiotics were overprescribed in their office. Among respondents, 74% reported intense pressure from patients to prescribe antimicrobials inappropriately. Immediate- and urgent-care prescribers had higher rates of compliance than primary-care prescribers, and the latter group responded well to monthly reports and online educational resources. Conclusions: Intense pressure from patients to prescribe antimicrobials when they are not indicated leads to overprescribing, an effect compounded by the importance of patient satisfaction scores. Compliance reporting improved the number of appropriate antibiotics prescribed in the primary care setting.

COVID-19 infection characteristics and outcomes in a predominantly Latino community hospital.

Introduction: The coronavirus disease 2019 (COVID-19) pandemic has rapidly spread worldwide and claimed millions of lives. Several studies have attempted to understand the relationship between COVID-19 infection and health disparities. The aim of the current work was to evaluate the pre-admission health characteristics, symptomatology, diagnostic abnormalities, treatment measures and clinical outcomes of the community served by our institution, with a sub-analysis of our Hispanic community. Methods: This is a single-center, cross-sectional cohort study of patients with COVID-19 admitted from 15 March 2020 to 30 April 2020 to MacNeal Hospital. A retrospective chart review was performed including patients >18 years and a positive nasopharyngeal SARS-CoV-2 PCR. Demographical data, comorbidities, clinical data, treatment regimen, and patient outcomes were collected. Results: A total of 257 patients were included in the study of which 60.4% were identified as Hispanic. The median age at admission of Hispanic patients was significantly lower compared to non-Hispanic patients (56.6 vs. 65.7 years, p<0.01). Non-Hispanic patients had lower prevalence of hypertension, coronary artery disease, and chronic lung disease. Most common at presentation were shortness of breath (69.6%), cough (69.2%), and fever (64%). Hypertension was the most common comorbidity (53.6%). Approximately 89% of the patients received antibiotics, 40.4% hydroxy-chloroquine, 13.2% steroids, and 6% tocilizumab. Twenty six percent required mechanical ventilation (MV), and over half of them (56.7%) were Hispanic. The strongest factors associated with MV were smoking (OR 2.97, 95%CI 1.01-8.69), CRP >10 mg/dL (OR 4.53, 95%CI 1.49-13.38) and D-dimer >1.5 mcg/mL (OR 3.63, 95%CI 1.31-10.05). An oxygen saturation of >90% on room air on presentation was a protective factor when predicting intubation (OR 0.11, 95%CI 0.03-0.33). The overall 30-day mortality rate was 17.1% (n=44); 11.9% in the Hispanic group vs 26.3% in the non-Hispanic group (p<0.003). Conclusions: Our review of consecutive patients admitted with COVID-19 demonstrated that over half of patients were of Hispanic descent. Interestingly enough, despite being significantly younger and healthier, the need for mechanical ventilation in the Hispanic group was not significantly different compared to the non-Hispanic group. However, the Hispanic group had a lower mortality rate.

Asymptomatic Bacteriuria: Prevalence, Diagnosis, Management, and Current Antimicrobial Stewardship Implementations.

Asymptomatic bacteriuria is a common clinical condition that often leads to unnecessary treatment. It has been shown that incidence of asymptomatic bacteriuria increases with age and are more prominent in women than men. In older women, the incidence of asymptomatic bacteriuria is recorded to be more than 15%. This number increased up to 50% for those who reside in long-term care facilities. In most scenarios, asymptomatic bacteriuria does not lead to urinary tract infections, and therefore, antibiotic treatment of asymptomatic bacteriuria has not been shown to improve patient outcomes. In 2019, the Infectious Disease Society of America (IDSA) updated its asymptomatic bacteriuria management guidelines, which emphasized on the risks and benefits of treating the condition. Women who are pregnant should be screened for asymptomatic bacteriuria in the first trimester and treated, if positive. Individuals who are undergoing endoscopic urologic procedures should be screened and treated appropriately for asymptomatic bacteriuria as well. Treating asymptomatic bacteriuria in individuals with diabetes, neutropenia, spinal cord injuries, indwelling urinary catheters, and so on has not been found to improve clinical outcomes. Furthermore, unnecessary treatment is often associated with unwanted consequences including but not limited to increased antimicrobial resistance, Clostridioides difficile infection, and increased health care cost. As a result, multiple antibiotic stewardship programs around the US have implemented protocols to appropriately reduce unnecessary treatment of asymptomatic bacteriuria. It is important to appropriately screen and treat asymptomatic bacteriuria only when there is evidence of potential benefit.

Impact of a Procalcitonin-Based Protocol on Antibiotic Exposure and Costs in Critically Ill Patients.

To examine the impact before and after adoption of a procalcitonin-based protocol to guide sepsis management has on antibiotic use, care costs, and outcomes of critically ill patients. DESIGN: Before-after study. SETTING: ICU of an academic tertiary care center. PATIENTS: Adults over 18 years old admitted to the ICU from January 1, 2017, to January 31, 2020. INTERVENTIONS: In this before-after study, we compared the use of medications, outcomes, and overall cost before and after the introduction of a procalcitonin-based protocol for evaluation and treatment of sepsis. MEASUREMENTS AND MAIN RESULTS: The final study cohort consisted of 1,793 patients admitted to the ICU, 776 patients pre-procalcitonin and 1,017 patients in the post-procalcitonin period. Patients were not different in the pre-procalcitonin adoption period compared with post-procalcitonin adoption with regard to gender, age (62.0 vs 62.6), race, or comorbidities. Patients admitted during the post-procalcitonin adoption period were less likely to receive the examined broad-spectrum antibiotics (odds ratio, -0.58; CI, -0.99 to -0.17; p < 0.01) than patients during the pre-procalcitonin adoption period. The odds of inhospital death did not differ after procalcitonin adoption when compared with before (0.87; CI, 0.70-1.09; p = 0.234). Total charges for each admission were significantly less in the post-procalcitonin adoption period $3,834.99 compared with pre-procalcitonin adoption $4,429.47 (p < 0.05). Patients post-procalcitonin adoption incurred $1,127.18 per patient less in total charges (-1,127.18; CI, -2,014.74 to -239.62; p = 0.013) after controlling for relevant factors. CONCLUSIONS: In critically ill patients in a large U.S. tertiary care hospital, the adoption of a procalcitonin-based protocol for evaluation and treatment of sepsis may be associated with decreased antibiotic use and significant cost savings, with no change in mortality.

Lactobacillus rhamnosus Infection: A Single-center 4-year Descriptive Analysis.

INTRODUCTION: Lactobacillus rhamnosus is an anaerobic or facultative anaerobic Gram-positive rod that is commonly found in the human gastrointestinal tract and vaginal tract. Infections secondary to L. rhamnosus have not been well illustrated in the literature. The purpose of this study was to describe the clinical courses of patients with L. rhamnosus infection in our institution. MATERIALS AND METHODS: A retrospective chart review was performed on patients with the growth of L. rhamnosus or L. rhamnosus/casei from January 1, 2013, to December 31, 2017. RESULTS: Forty-seven patients had growth of L. rhamnosus or L. rhamnosus/casei. Of these, 35 patients were included in the study who received therapy. Twenty patients (57.1%) presented with leukocytosis, 17 (48.5%) with fever, and 15 (42.8%) with abdominal pain. Twenty-three (66.1%) had intra-abdominal infection, 8 (22.3%) were bacteremic, and 4 (11.4%) had mediastinitis. Thirty-three patients (94.3%) had a polymicrobial infection. Eighteen (51.4%) patients had disruption of the gastrointestinal tract, 14 (40.0%) had underlying malignancy, and 11 (31.4%) had prior antibiotic exposure. Twenty (57.1%) patients clinically improved after therapy. However, the overall mortality rate was 56.2%, all of whom died of unrelated causes. CONCLUSION: Lactobacilli are organisms thought to have low pathogenicity. Our study identified cases of L. rhamnosus infections in a population of patients with serious underlying medical conditions.

Variability in antifungal stewardship strategies among Society for Healthcare Epidemiology of America (SHEA) Research Network facilities.

OBJECTIVE: To characterize antifungal stewardship among antimicrobial stewardship programs (ASPs) at a diverse range of hospitals and to correlate antifungal stewardship with hospital characteristics. DESIGN: Cross-sectional survey. PARTICIPANTS: ASP physician and/or pharmacist members at Society for Healthcare Epidemiology of America (SHEA) Research Network (SRN) hospitals. METHODS: An electronic survey administered August-September 2018 via the SRN to 111 hospitals. The χ2 test was used to test associations between ASP and hospital characteristics and use of antifungal stewardship strategies. RESULTS: Of 111 hospitals, 45 (41%) responded; most were academic medical centers (65%) caring for stem-cell patients (73.3%) and solid-organ transplant patients (80.0%). Most hospitals have large, well-established ASPs: 60% had >5 team members and 68.9% had a duration ≥6 years. In 43 hospitals (95.6%), ASPs used antifungal stewardship strategies, most commonly prospective audit and feedback (73.3%) by a pharmacist (71.4%). Half of ASPs (51.1%) created guidelines for invasive fungal infection (IFI) management. Most hospitals (71.1%) offered rapid laboratory tests to diagnose IFI, but polymerase chain reaction (PCR) testing and antifungal susceptibility testing varied. Also, 29 ASPs (64.4%) perform surveillance of antifungal utilization, but only 9 (31%) reported to the CDC National Healthcare Safety Network. ASP size, duration, and presence of transplant populations were not associated with a higher likelihood of using antifungal stewardship strategies (P > .05 for all). CONCLUSIONS: The use of antifungal stewardship strategies was high at SRN hospitals, but they mainly involved audit and feedback. ASPs should be encouraged (1) to disseminate guidelines for IFI management, (2) to promote access to laboratory tests for rapid and accurate IFI diagnosis, and (3) to perform surveillance for antifungal utilization with reporting to the CDC.

In Vitro Pharmacodynamic Analyses Help Guide the Treatment of Multidrug-Resistant Enterococcus faecium and Carbapenem-Resistant Enterobacter cloacae Bacteremia in a Liver Transplant Patient.

BACKGROUND: Infections due to multidrug-resistant pathogens are particularly deadly and difficult to treat in immunocompromised patients, where few data exist to guide optimal antimicrobial therapy. In the absence of adequate clinical data, in vitro pharmacokinetic (PK)/pharmacodynamic (PD) analyses can help to design treatment regimens that are bactericidal and may be clinically effective. METHODS: We report a case in which in vitro pharmacodynamic analyses were utilized to guide the treatment of complex, recurrent bacteremias due to vancomycin-, daptomycin-, and linezolid-resistant Enterococcus faecium and carbapenem-resistant Enterobacter cloacae complex in a liver transplant patient. RESULTS: Whole-genome sequencing revealed unique underlying resistance mechanisms and explained the rapid evolution of phenotypic resistance and complicated intrahost genomic dynamics observed in vivo. Performing this comprehensive genotypic and phenotypic testing and time-kill analyses, along with knowledge of institution and patient-specific factors, allowed us to use precision medicine to design a treatment regimen that maximized PK/PD. CONCLUSIONS: This work provides a motivating example of clinicians and scientists uniting to optimize care in the era of escalating antimicrobial resistance.