Impact of an Antimicrobial Stewardship Bundle for Uncomplicated Gram-Negative Bacteremia

Rapid Diagnostic Tests and Antimicrobial Stewardship Programs for the Management of Bloodstream Infection: What Is Their Relative Contribution to Improving Clinical Outcomes? A Systematic Review and Network Meta-analysis

BACKGROUND

Evidence about the clinical impact of rapid diagnostic tests (RDTs) for the diagnosis of bloodstream infections is limited, and whether RDT are superior to conventional blood cultures (BCs) embedded within antimicrobial stewardship programs (ASPs) is unknown.

METHODS

We performed network meta-analyses using results from studies of patients with bloodstream infection with the aim of comparing the clinical impact of RDT (applied on positive BC broth or whole blood) to conventional BC, both assessed with and without ASP with respect to mortality, length of stay (LOS), and time to optimal therapy.

RESULTS

Eighty-eight papers were selected, including 25 682 patient encounters. There was an appreciable amount of statistical heterogeneity within each meta-analysis. The network meta-analyses showed a significant reduction in mortality associated with the use of RDT + ASP versus BC alone (odds ratio [OR], 0.72; 95% confidence interval [CI], .59-.87) and with the use of RDT + ASP versus BC + ASP (OR, 0.78; 95% CI, .63-.96). No benefit in survival was found associated with the use of RDT alone nor with BC + ASP compared to BC alone. A reduction in LOS was associated with RDT + ASP versus BC alone (OR, 0.91; 95% CI, .84-.98) whereas no difference in LOS was shown between any other groups. A reduced time to optimal therapy was shown when RDT + ASP was compared to BC alone (-29 hours; 95% CI, -35 to -23), BC + ASP (-18 hours; 95% CI, -27 to -10), and to RDT alone (-12 hours; 95% CI, -20 to -3).

CONCLUSIONS

The use of RDT + ASP may lead to a survival benefit even when introduced in settings already adopting effective ASP in association with conventional BC.

Antimicrobial Stewardship in Immunocompromised Patients: Current State and Future Opportunities

Immunocompromised (IC) patients are high risk for complications due to a high rate of antibiotic exposure. Antimicrobial stewardship interventions targeted to IC patients can be challenging due to limited data in this population and a high risk of severe infection-related outcomes. Here, the authors review immunocompromised antimicrobial stewardship barriers, metrics, and opportunities for antimicrobial use and testing optimization. Last, the authors highlight future steps in the field.

Infectious disease physician characteristics and prescription of meropenem in the hospital

Objective

Physician characteristics may be correlated with medical treatment decisions and patient outcomes. This study examined the correlations between characteristics of infectious disease (ID) physicians and the use of the restricted antimicrobial meropenem.

Design

This was a retrospective cohort study following 27 attending ID physicians for 5 years at a large academic medical center.

Methods

All inpatient ID clinical encounters between 2013 and 2018 were assessed for physician and patient characteristics, including patient Charlson Comorbidity Index, patient sex, ID service seeing the patient, physician career stage, physician training location, and physician sex. Adjusted and unadjusted odds ratios were calculated for the receipt of meropenem on the same day as an ID clinical note.

Results

Between 2013 and 2018, meropenem was administered on the same day as 9046 (11.1%) of 81,787 inpatient ID encounters. After adjustment for patient and practice-specific factors, physician career stage was associated with administration of meropenem. Patients seen by mid-career and late-career ID physicians were more likely to receive meropenem than those seen by early-career physicians (aOR 1.22 95% confidence interval [CI 1.13-1.31 and aOR 1.17 95% CI 1.10-1.25, respectively).

Conclusions

ID provider characteristics may help target future antimicrobial stewardship program interventions.

Impact of a Pro-Active Infectious Disease Consultation on the Management of a Multidrug-Resistant Organisms Outbreak in a COVID-19 Hospital: A Three-Months Quasi-Experimental Study

Background: Antimicrobial and diagnostic stewardship (AS/DS) principles are crucial for the management of multidrug-resistant organisms (MDROs) infections. We evaluated the impact of a pro-active Infectious Disease (ID) consultation on the mortality risk of patients during an MDROs outbreak in a COVID-19 hospital. Methods: A quasi-experimental study was performed in a dedicated COVID-19 hospital, including patients with suspected/confirmed infection and/or colonization by MDROs, which were managed as follows: (i) according to the standard of care during the pre-phase and (ii) in collaboration with a dedicated ID team performing a pro-active bedside evaluation every 48–72 h in the post-phase. Results: Overall, 112 patients were included (pre-phase = 89 and post-phase = 45). The AS interventions included the following: therapy optimization (33%), de-escalation to narrow the spectrum (24%) or to lessen toxic drugs (20%), and discontinuation of antimicrobials (64%). DS included the request of additional microbiologic tests (82%) and instrumental exams (16%). With the Cox model, after adjusting for age, sex, COVID-19 severity, infection source, etiological agents, and post-phase attendance, only age predicted an increased risk of mortality, while attendance in the post-phase resulted in a decreased risk of mortality. Conclusions: Implementation of AS and DS intervention through a pro-active ID consultation may reduce the risk of 28-day mortality of COVID-19 patients with MDROs infections.

Impact of specialty on the self-reported practice of using oral antibiotic therapy for definitive treatment of bloodstream infections

Background:

No established guidelines exist regarding the role of oral antibiotic therapy (OAT) to treat bloodstream infections (BSIs), and practices may vary depending on clinician specialty and experience.

Objective:

To assess practice patterns regarding oral antibiotic use for treatment of bacteremia in infectious diseases clinicians (IDCs, including physicians and pharmacists and trainees in these groups) and non–infectious diseases clinicians (NIDCs).

Design:

Open-access survey.

Participants:

Clinicians caring for hospitalized patients receiving antibiotics.

Methods:

An open-access, web-based survey was distributed to clinicians at a Midwestern academic medical center using e-mail and to clinicians outside the medical center using social media. Respondents answered questions regarding confidence prescribing OAT for BSI in different scenarios. We used χ2 analysis for categorical data evaluated association between responses and demographic groups.

Results:

Of 282 survey responses, 82.6% of respondents were physicians, 17.4% pharmacists, and IDCs represented 69.2% of all respondents. IDCs were more likely to select routine use of OAT for BSI due to gram-negative anaerobes (84.6% vs 59.8%; P < .0001), Klebsiella spp (84.5% vs 69.0%; P < .009), Proteus spp (83.6% vs 71.3%; P < .027), and other Enterobacterales (79.5% vs 60.9%; P < .004). Our survey results revealed significant differences in selected treatment of Staphylococcus aureus syndromes. Fewer IDCs than NIDCs selected OAT to complete treatment for methicillin-resistant S. aureus (MRSA) BSI due to gluteal abscess (11.9% vs 25.6%; P = .012) and methicillin-susceptible S. aureus (MSSA) BSI due to septic arthritis (13.9% vs 20.9%; P = .219).

Conclusions:

Practice variation and discordance with evidence for the use of OAT for BSIs exists among IDCs versus NIDCs, highlighting opportunities for education in both clinician groups.

Antibiotic Overuse and Stewardship at Hospital Discharge: The Reducing Overuse of Antibiotics at Discharge (ROAD) Home Framework

Though opportunities exist to improve antibiotic prescribing across the care spectrum, discharge from acute hospitalization is an increasingly recognized source of antibiotic overuse. Antimicrobials are prescribed to more than 1 in 8 patients at hospital discharge; approximately half of which could be improved. Key targets for antibiotic stewardship at discharge include unnecessary antibiotics, excess duration, avoidable fluoroquinolones, and improving (or avoiding) intravenous antibiotic therapy. Barriers to discharge antibiotic stewardship include the perceived “high stakes” of care transitions during which patients move from intense to infrequent observation, difficulties in antibiotic measurement to guide improvement at discharge, and poor communication across silos, particularly with skilled nursing facilities. In this review, we discuss what is currently known about antibiotic overuse at hospital discharge, key barriers, and targets for improving antibiotic prescribing at discharge and we introduce an evidence-based framework, the Reducing Overuse of Antibiotics at Discharge Home Framework, for conducting discharge antibiotic stewardship.

Impact of an Antimicrobial Stewardship Program-bundled initiative utilizing Accelerate Pheno™ system in the management of patients with aerobic Gram-negative bacilli bacteremia

PURPOSE

Gram-negative bacteria (GNB) are a leading cause of bloodstream infections (BSI) and management is complicated by antibiotic resistance. The Accelerate Pheno™ system (ACC) can provide rapid organism identification and antimicrobial susceptibility testing (AST).

METHODS

A retrospective, pre-intervention/post-intervention study was conducted to compare management of non-critically ill patients with GNB BSI before and after implementation of a bundled initiative. This bundled initiative included dissemination of a clinical decision algorithm, ACC testing on all GNB isolated from blood cultures, real-time communication of results to the Antimicrobial Stewardship Program (ASP), and prospective audit with feedback by the ASP. The pre-intervention period was January 2018 through December 2018, and the post-intervention period was May 2019 through February 2020.

RESULTS

Seventy-seven and 129 patients were included in the pre-intervention and post-intervention cohorts, respectively. When compared with the pre-intervention group, the time from Gram stain to AST decreased from 46.1 to 6.9 h (p < 0.001), and the time to definitive therapy (TTDT) improved from 32.6 to 10.5 h (p < 0.001). Implementation led to shorter median total duration of antibiotic therapy (14.2 vs 9.5 days; p < 0.001) and mean hospital length of stay (7.9 vs 5.3 days; p = 0.047) without an increase in 30-day readmissions (22.1% vs 14%; p = 0.13).

CONCLUSION

Implementation of an ASP-bundled approach incorporating the ACC aimed at optimizing antibiotic therapy in the management GNB BSI in non-critically ill patients led to reduced TTDT, shorter duration of antibiotic therapy, and shorter hospital length of stay without adversely affecting readmission rates.

Potential interventions for an antimicrobial stewardship bundle for Escherichia coli bacteraemia

INTRODUCTION

Escherichia coli is the most commonly identified bacteraemia, and causes a broad spectrum of diseases. The range of clinical conditions associated with E. coli bacteraemia mean that antimicrobial therapy is highly variable. This study aimed to determine the workload, efficiency and potential impact of an antimicrobial stewardship (AMS) bundle approach to E. coli bacteraemia.

METHODS

An observational cohort study of patients with E. coli bacteraemia was performed, and a review of each case's entire medical record was undertaken. A number of AMS interventions were modelled on this cohort to assess their impact on overall days of antimicrobial therapy and time to optimized antimicrobial therapy.

RESULTS

In total, 566 episodes of E. coli bacteraemia were identified. A number of AMS interventions were modelled to assess their impact. The strict implementation of guideline-based therapy was found to increase the number of patients receiving ineffective empirical therapy to 38/266 (14.3%) compared with 27/266 (10.2%) patients when w hen non-guideline-adherent therapy was allowed. A scheduled review by an AMS team on day 3 of empirical therapy could lead to a narrower-spectrum intravenous antibiotic in 237/515 (46%) cases, and 386 cases (68.2% of cohort) could have their duration of therapy reduced by a median of 7 days.

CONCLUSION

This study provides detailed description of a large cohort of patients with E. coli bacteraemia. There remains significant variability in empirical treatment, choice of step-down therapy and antimicrobial duration. A significant opportunity exists for AMS programmes to impact the management of E. coli bacteraemia through a bundled approach.

Are Follow-Up Blood Cultures Useful in the Antimicrobial Management of Gram Negative Bacteremia? A Reappraisal of Their Role Based on Current Knowledge

Bloodstream infections still constitute an outstanding cause of in-hospital morbidity and mortality, especially among critically ill patients. Follow up blood cultures (FUBCs) are widely recommended for proper management of Staphylococcus aureus and Candida spp. infections. On the other hand, their role is still a matter of controversy as far as Gram negative bacteremias are concerned. We revised, analyzed, and commented on the literature addressing this issue, to define the clinical settings in which the application of FUBCs could better reveal its value. The results of this review show that critically ill patients, endovascular and/or non-eradicable source of infection, isolation of a multi-drug resistant pathogen, end-stage renal disease, and immunodeficiencies are some factors that may predispose patients to persistent Gram negative bacteremia. An analysis of the different burdens that each of these factors have in this clinical setting allowed us to suggest which patients’ FUBCs have the potential to modify treatment choices, prompt an early source control, and finally, improve clinical outcome.

Is Early Oral Antimicrobial Switch Useful for Less Critically Ill Adults with Community-Onset Bacteraemia in Emergency Departments?

To compare prognoses and adverse events between bacteraemic patients in the emergency department (ED) who received an early antimicrobial IV-to-PO switch and those treated with late or no IV-to-PO switch, an 8-year multicentre cohort consisting of adults with community-onset bacteraemia was conducted. The clinical characteristics and outcomes were compared in matched cohorts by the closest propensity score calculated based on the independent determinants of 30-day mortality identified by the multivariate regression model. Of the 6664 hospitalised patients who received no or late IV-to-PO switch, 2410 were appropriately matched with 482 patients treated with early IV-to-PO switch and discharged from the ED. There were no significant differences between the two matched groups in their baseline characteristics, including the patient demographics, severity and types of comorbidities, severity and sources of bacteraemia, and the 15- and 30-day mortality rates. Notably, in addition to the shorter lengths of intravenous antimicrobial administration and hospital stay, less phlebitis and lower antimicrobial costs were observed in patients who received an early IV-to-PO switch. Similarity was observed in the clinical failure rates between the two groups. Furthermore, the inappropriate administration of empirical antibiotics and inadequate source control were identified as the only independent determinants of the post-switch 30-day crude mortality in patients who received an early IV-to-PO switch. In conclusion, for less critically ill adults with community-onset bacteraemia who received appropriate empirical antimicrobial therapy and adequate source control, an early IV-to-PO switch might be safe and cost-effective after a short course of intravenous antimicrobial therapy.

Oral β-Lactam Antibiotics vs Fluoroquinolones or Trimethoprim-Sulfamethoxazole for Definitive Treatment of Enterobacterales Bacteremia From a Urine Source

Importance

Oral β-lactam antibiotics are traditionally not recommended to treat Enterobacterales bacteremia because of concerns over subtherapeutic serum concentrations, but there is a lack of outcomes data, specifically after initial treatment with parenteral antibiotics. Given the limited data and increasing limitations of fluoroquinolones or trimethoprim-sulfamethoxazole (TMP-SMX), oral β-lactam antibiotics may be a valuable additional treatment option.

Objective

To compare definitive therapy with oral β-lactam antibiotics vs fluoroquinolones or TMP-SMX for Enterobacterales bacteremia from a suspected urine source.

Design, Setting, and Participants

A retrospective cohort study was conducted from January 1, 2007, to September 30, 2015, at 114 Veterans Affairs hospitals among 4089 adults with Escherichia coli, Klebsiella spp, or Proteus spp bacteremia and matching urine culture results. Additional inclusion criteria were receipt of active parenteral antibiotic(s) followed by conversion to an oral antibiotic. Exclusion criteria were previous Enterobacterales bacteremia, urologic abscess, or chronic prostatitis. Data were analyzed from April 15, 2019, to July 26, 2020.

Exposures

Conversion of therapy to an oral β-lactam antibiotic vs fluoroquinolones or TMP-SMX after 1 to 5 days of parenteral antibiotics.

Main Outcomes and Measures

The main outcome was a composite of either 30-day all-cause mortality or 30-day recurrent bacteremia. Propensity-based overlap weights were used to adjust for differences between groups. Log binomial regression models were used to estimate adjusted relative risks (aRRs) and adjusted risk differences (aRDs).

Results

Of the 4089 eligible patients (3731 men [91.2%]; median age, 71 years [interquartile range, 63-81 years]), 955 received an oral β-lactam antibiotic, and 3134 received fluoroquinolones or TMP-SMX. The primary outcome occurred for 42 patients (4.4%) who received β-lactam antibiotics and 94 patients (3.0%) who received fluoroquinolones or TMP-SMX (aRD, 0.99% [95% CI, -0.42% to 2.40%]; aRR, 1.31 [95% CI, 0.87-1.95]). Mortality rates were 3.0% (n = 29) for patients receiving β-lactam antibiotics vs 2.6% (n = 82) for those receiving fluoroquinolones or TMP-SMX (aRD, 0.06% [95% CI, -1.13% to 1.26%]; aRR, 1.02 [95% CI, 0.67-1.56]). Recurrent bacteremia rates were 1.5% (n = 14) among those receiving β-lactam antibiotics vs 0.4% (n = 12) among those receiving fluoroquinolones or TMP-SMX (aRD, 1.03% [95% CI, 0.24%-1.82%]; aRR, 3.43 [95% CI, 0.42-27.90]).

Conclusions and Relevance

In this cohort study of adults with E coli, Klebsiella spp, or Proteus spp bacteremia from a suspected urine source, the relative risk of recurrent bacteremia was not significantly higher with β-lactam antibiotics compared with fluoroquinolones or TMP-SMX, and the absolute risk and risk difference were small (ie, <3%). No significant difference in mortality was observed. Oral β-lactam antibiotics may be a reasonable step-down treatment option, primarily when alternative options are limited by resistance or adverse effects. Further study is needed because statistical power was limited owing to a low number of recurrent bacteremia events.

Short-course versus long-course antibiotic treatment in patients with uncomplicated gram-negative bacteremia: A systematic review and meta-analysis

What is known and objective

Gram‐negative bacteremia remains a major health problem around the world. The optimal duration of antibiotic treatment has been poorly defined, and there are significant differences of opinion between clinicians. We conducted this systematic review and meta‐analysis to compare the clinical outcomes of short‐course and long‐course treatments in patients with uncomplicated gram‐negative bacteremia.

Methods

We searched public databases (PubMed, EMBASE and Cochrane Library) to identify eligible studies. The primary outcomes were all‐cause mortality and the incidence of recurrent bacteremia through day 30. We used the Cochrane risk of bias assessment tool to evaluate the risk of bias for randomized controlled trials (RCTs) and the Newcastle‐Ottawa Scale for non‐RCTs.

Results and discussion

Six studies involving 2689 patients were included in the systematic review and meta‐analysis. No significant difference was found between short‐course and long‐course antibiotic treatments in 30‐day mortality (risk ratio [RR] 0.85; 95% confidence interval [CI] 0.65‐1.13; P = .26), 30‐day recurrent bacteremia (RR 1.07; 95% CI 0.68‐1.67; P = .78), 90‐day mortality (RR 0.84; 95% CI 0.57‐1.24; P = .38), 90‐day recurrent bacteremia (RR 0.98; 95% CI 0.50‐1.89; P = .94), adverse events (RR 1.14; 95% CI 0.89‐1.45; P = .30), Clostridium difficile infection (RR 0.86; 95% CI 0.40‐1.86; P = .71) or resistance development (RR 1.19; 95% CI 0.66‐2.14; P = .57).

What is new and conclusion

Short‐course was non‐inferior to long‐course antibiotic treatments for patients with uncomplicated gram‐negative bacteremia. Considering the drug‐related side effects and cost‐effectiveness, a shorter duration of antibiotic treatment may be preferable for this particular population. However, additional high‐quality RCTs are needed to further assess whether a shorter course of antibiotic treatment is of greater benefit for patients with uncomplicated gram‐negative bacteremia.

A Baker's Dozen of Top Antimicrobial Stewardship Intervention Publications in 2019

Staying current on literature related to antimicrobial stewardship can be challenging given the ever-increasing number of published articles. The Southeastern Research Group Endeavor (SERGE-45) identified antimicrobial stewardship–related peer-reviewed literature that detailed an actionable intervention for 2019. The top 13 publications were selected using a modified Delphi technique. These manuscripts were reviewed to highlight the actionable intervention used by antimicrobial stewardship programs to provide key stewardship literature for teaching and training and to identify potential intervention opportunities within one’s institution.