Impact of Antimicrobial Stewardship Program (ASP) on Outcomes in Patients with Acute Bacterial Skin and Skin Structure Infections (ABSSSIs) in an Acute-Tertiary Care Hospital

Antibiotic utilisation and resistance over the first decade of nationally funded antimicrobial stewardship programmes in Singapore acute-care hospitals

OBJECTIVE

The aim of this study was to describe the time series of broad-spectrum antibiotic utilisation and incidence of antibiotic-resistant organisms during the implementation of antimicrobial stewardship programmes (ASP) in Singapore.

METHODS

An observational study was conducted using data from 2011 to 2020 in seven acute-care public hospitals. We applied joinpoint regressions to investigate changes in antibiotic utilisation rate and incidence density of antibiotic-resistant organisms.

RESULTS

Across the seven hospitals, quarterly broad-spectrum antibiotic utilisation rate remained stable. Half-yearly incidence density of antibiotic-resistant organisms with two joinpoints at first half (H1) of 2012 and second half (H2) of 2014 decreased significantly in the second and third period with a half-yearly percentage change (HPC) of -2.9% and - 0.5%, respectively. Across the five hospitals with complete data, half-yearly broad-spectrum antibiotic utilisation rate with one joinpoint decreased significantly from H1 of 2011 to H2 of 2018 (HPC - 4.0%) and H2 of 2018 to H2 2020 (HPC - 0.5%). Incidence density of antibiotic-resistant organisms decreased significantly in the two joinpoint periods from H1 of 2012 to H2 of 2014 (HPC - 2.7%) and H2 of 2014 to H2 of 2020 (HPC - 1.0%). Ceftriaxone with one joinpoint decreased significantly from H1 of 2011 to H1 of 2014 (HPC - 6.0%) and H1 of 2014 to H2 of 2020 (HPC - 1.8%) and ceftriaxone-resistant E. coli and K. pneumoniae decreased significantly in later periods, from H2 of 2016 to H2 of 2020 (HPC - 2.5%) and H1 of 2012 to H2 of 2015 (HPC - 4.6%) respectively. Anti-pseudomonal antibiotics with one joinpoint decreased significantly from H1 of 2011 to H2 of 2014 (HPC - 4.5%) and H2 of 2014 to H2 of 2020 (HPC - 0.8%) and that of quinolones with one joinpoint at H1 of 2015 decreased significantly in the first period. C. difficile with one joinpoint increased significantly from H1 of 2011 to H1 of 2015 (HPC 3.9%) and decreased significantly from H1 of 2015 to H2 of 2020 (HPC - 4.9%).

CONCLUSIONS

In the five hospitals with complete data, decrease in broad-spectrum antibiotic utilisation rate was followed by decrease in incidence density of antibiotic-resistant organisms. ASP should continue to be nationally funded as a key measure to combat antimicrobial resistance in acute care hospitals.

Evaluation of antibiotic appropriateness at an outpatient oncology centre

Current evidence supporting antimicrobial stewardship programs focused largely in inpatient setting. With the shift in cancer management from inpatient to ambulatory setting, it is crucial to examine the prevalence and predictors of inappropriate antibiotics prescribing. This is a retrospective cross-sectional study conducted at the National Cancer Centre Singapore (NCCS). Patients at least 21 years, with an active or past cancer diagnosis and prescribed with at least one oral antibiotic by a NCCS physician from 1st July to 30th September 2019 were included. Antibiotic appropriateness was assessed using institutional antibiotic guidelines or published clinical practice guidelines. For cases where antibiotics appropriateness cannot be ascertained using these guidelines, an independent three-member expert panel was consulted. A total of 815 patients were screened; 411 (59.4% females) were included with mean age of 62.4 years. The top three cancer diagnoses were breast (26.5%), lung (15.6%) and head and neck (13.6%). More than half (58.6%) received appropriate antibiotic choice. Of which, 235 (97.5%), 238 (98.8%) and 194 (80.5%) received appropriate dose, frequency and duration respectively. The presence of non-oncologic immunosuppressive comorbidities (OR 4.890, 95% CI 1.556-15.369, p-value = 0.007), antibiotic allergy (OR 2.352, 95% CI 1.178-4.698, p-value = 0.015) and skin and soft tissue infections (OR 2.004, 95% CI 1.276-3.146, p-value = 0.003) were associated with a higher incidence of inappropriate antibiotic choice. This study highlighted that inappropriate antibiotic prescribing is prevalent in the ambulatory oncology setting. Predicators identified can aid in the design of targeted strategies to optimise antibiotic use in ambulatory oncology patients.

Effectiveness of Implementing a Locally Developed Antibiotic Use Guideline for Community-Acquired Cellulitis at a Large Tertiary Care University Hospital in Thailand

Background

To determine the effectiveness of implementing a locally developed clinical practice guideline (CPG) for antibiotic treatment in adults with community-acquired cellulitis at Siriraj Hospital in Bangkok, Thailand.

Methods

The CPG for antibiotic treatment of community-acquired cellulitis was developed based on local data during June to December 2016. The CPG was introduced by multifaceted interventions, including posters, brochures, circular letters, social media, conference, classroom training, and interactive education during January to September 2018.

Results

Among 360 patients with community-acquired cellulitis, 84.4% were ambulatory and 15.6% were hospitalized. The median age of patients was 62 years, and 59.4% were female. Antibiotic prescription according to CPG (CPG-compliant group) was observed in 251 patients (69.7%), and CPG noncompliance was found in 109 patients (30.3%) (CPG-noncompliant group). The demographics and characteristics of patients were comparable between groups. Patients in the CPG-compliant group had a significantly lower rate of intravenous antibiotics (18.7% vs 33.9%, P = .007), lower prescription rate of broad-spectrum antibiotics (14.7% vs 78.9%, P < .001) and antibiotic combination (6.4% vs 13.8%, P = .022), shorter median duration of antibiotic treatment (7 vs 10 days, P < .001), lower median cost of antibiotic treatment (US $3 vs $7, P < .001), and lower median hospitalization cost (US $601 vs $1587, P = .008) than those in the CPG-noncompliant group. Treatment outcomes were not significantly different between groups.

Conclusions

Adherence to CPG seems to reduce inappropriate prescription of broad-spectrum antibiotic or antibiotic combination and treatment costs in adults with community-acquired cellulitis without differences in favorable outcomes or adverse events.

Impact of antimicrobial de-escalation on mortality: a literature review of study methodology and recommendations for observational studies

Introduction: The safety of de-escalation of empirical antimicrobial therapy is largely based on observational data, with many reporting protective effects on mortality. As there is no plausible biological explanation for this phenomenon, it is most probably caused by confounding by indication.Areas covered: We evaluate the methodology used in observational studies on the effects of de-escalation of antimicrobial therapy on mortality. We extended the search for a recent systematic review and identified 52 observational studies. The heterogeneity in study populations was large. Only 19 (36.5%) studies adjusted for confounders and four (8%) adjusted for clinical stability during admission, all as a fixed variable. All studies had methodological limitations, most importantly the lack of adjustment for clinical stability, causing bias toward a protective effect.Expert opinion: The methodology used in studies evaluating the effects of de-escalation on mortality requires improvement. We depicted all potential confounders in a directed acyclic graph to illustrate all associations between exposure (de-escalation) and outcome (mortality). Clinical stability is an important confounder in this association and should be modeled as a time-varying variable. We recommend to include de-escalation as time-varying exposure and use inverse-probability-of-treatment weighted marginal structural models to properly adjust for time-varying confounders.

Antimicrobial stewardship in patients with acute bacterial skin and skin-structure infections: An international Delphi consensus

OBJECTIVES

The aim of this survey was to identify a set of actions aimed to improve the diagnosis and management of acute bacterial skin and skin-structure infections (ABSSSIs) and the implementation of some principles of antimicrobial stewardship (AMS) in this setting.

METHODS

A list of 76 statements for which there was a lack of clarity were generated by an expert panel and were validated by a group of experts. The questionnaire was administered to 112 experts in infectious diseases or microbiology. Participants were asked to vote on a list of statements. An agreement threshold of 66% was required to reach consensus.

RESULTS

Overall, 57 responders participated in the survey. Positive consensus was reached on the fact that ABSSSIs represent a significant cause of infection in the emergency department, are frequently associated with increased hospital stay and are mainly caused by Staphylococcus aureus. The panellists strongly supported collection of samples from purulent infections by needle aspiration as well as collection of blood cultures in the presence of signs/symptoms of systemic infection. The importance of source control and prompt adequate microbiological documentation, the objective to reduce the length of hospital stay, the choice of a narrow-spectrum antibiotic and the role of new therapeutic options (e.g. long-acting drugs) in improving compliance also reached a positive consensus.

CONCLUSION

This Delphi survey provides useful indicators for the implementation of AMS principles in the clinical management of ABSSSI and offers interesting elements of discussion about the barriers existing in Europe for optimal implementation of AMS programmes.

Effects of an automatic discontinuation of antibiotics policy: A novel approach to antimicrobial stewardship

PURPOSE

A novel automatic discontinuation policy implemented within an antimicrobial stewardship program (ASP) is described, and results of an evaluation of the policy's effects on antibiotic usage are reported.

METHODS

A retrospective, before-and-after study was conducted at an 800-bed, tertiary care, academic teaching hospital to evaluate selected antibiotic usage outcomes in both intensive care unit (ICU) and non-ICU adult patients targeted for ASP interventions before and after implementation of an automatic discontinuation of antibiotics policy (ADAP) authorizing the ASP team to automatically halt antibiotic therapy in cases involving inappropriate duplicate antimicrobial coverage or excess duration of therapy. The primary outcome was total days of antibiotic therapy. Secondary outcomes included excess days of therapy and rates of 30-day readmission, Clostridioides difficile infection, and multidrug-resistant infection.

RESULTS

There were no statistically significant differences in group demographics or clinical characteristics. The most common indication for antibiotics was hospital-acquired pneumonia, and the most common reason for ASP intervention was excess duration of therapy. The mean total number of antibiotic days per patient was reduced from 7.6 days in the pre-ADAP group to 6.6 days in the post-ADAP group (p < 0.05). The mean number of excess days of antibiotics was similarly reduced, from 2.3 days to 1.5 days, after implementation of the ADAP (p < 0.05).

CONCLUSION

Adoption of an ADAP-a more active approach to ASP interventions-was effective in reducing overall antibiotic usage and improving the efficiency of the ASP.

Ten-year narrative review on antimicrobial resistance in Singapore

Antimicrobial resistance (AMR) results in drug-resistant infections that are harder to treat, subsequently leading to increased morbidity and mortality. In 2008, we reviewed the problem of AMR in Singapore, limiting our discussion to the human healthcare sector. Ten years later, we revisit this issue again, reviewing current efforts to contain it in order to understand the progress made as well as current and emerging challenges. Although a significant amount of work has been done to control AMR and improve antibiotic prescribing in Singapore, most of it has focused on the hospital setting, with mixed impact. The role of antibiotic use and AMR in food animals and the environment - and the link to human health - is better understood today. This issue of AMR encompasses both human health as well as animal/food safety, and efforts to control it will need to continually evolve to maintain or improve on current gains.

Management of complicated skin and soft tissue infections with a special focus on the role of newer antibiotics

Complicated skin and soft tissue infections (cSSTIs) represent the severe form of infectious disease that involves deeper soft tissues. Involvement of methicillin-resistant Staphylococcus aureus (MRSA) further complicates cSSTI with increased hospitalization, health care costs, and overall mortality. Various international guidelines provide recommendations on the management of cSSTIs, with the inclusion of newer antibiotics. This literature-based review discusses the overall management of cSSTI, including appropriate use of antibiotics in clinical practice. Successful treatment of cSSTIs starts with early and precise diagnosis, including identification of causative pathogen and its load, determination of infection severity, associated complications, and risk factors. The current standard-of-care for cSSTIs involves incision, drainage, surgical debridement, broad-spectrum antibiotic therapy, and supportive care. In recent years, the emergence of newer antibiotics (eg, ceftaroline, tigecycline, daptomycin, linezolid, etc) has provided clinicians wider options of antimicrobial therapy. Selection of antibiotics should be based on the drug characteristics, effectiveness, safety, and treatment costs, alongside other aspects such as host factors and local multidrug resistance rates. However, larger studies on newer antibiotics are warranted to refine the decision making on the appropriate antimicrobial therapy. Local Antimicrobial Stewardship Program strategies in health care settings could guide clinicians for early initiation of specific treatments to combat region-specific antimicrobial resistance, minimize adverse effects, and to improve outcomes such as reduction in Clostridium difficile infections. These strategies involving iv-to-oral switch, de-escalation to narrow-spectrum antibiotics, and dose optimization have an impact on the overall improvement of cSSTI therapy outcomes, especially in countries like Singapore that has a high disease burden.

Antimicrobial stewardship for acute-care hospitals: An Asian perspective

Inappropriate use of antibiotics is contributing to a serious antimicrobial resistance problem in Asian hospitals. Despite resource constraints in the region, all Asian hospitals should implement antimicrobial stewardship (AMS) programs to optimize antibiotic treatment, improve patient outcomes, and minimize antimicrobial resistance. This document describes a consensus statement from a panel of regional experts to help multidisciplinary AMS teams design programs that suit the needs and resources of their hospitals. In general, AMS teams must decide on appropriate interventions (eg, prospective audit and/or formulary restriction) for their hospital, focusing on the most misused antibiotics and problematic multidrug-resistant organisms. This focus is likely to include carbapenem use with the goal to reduce carbapenem-resistant gram-negative bacteria. Rather than initially trying to introduce a comprehensive, hospital-wide AMS program, it would be practical to begin by pilot testing a simple program based on 1 achievable core intervention for the hospital. AMS team members must work together to determine the most suitable AMS interventions to implement in their hospitals and how best to put them into practice. Continuous monitoring and feedback of outcomes to the AMS teams, hospital administration, and prescribers will enhance sustainability of the AMS programs.

Fast track SSTI management program based on a rapid molecular test (GeneXpert® MRSA/SA SSTI) and antimicrobial stewardship

PURPOSE

This study examines the impacts of a skin and soft tissue infection (SSTI) management program involving a rapid diagnostic algorithm (Gram stain plus real-time PCR, GeneXpert® MRSA/SA SSTI) performed directly on clinical samples plus antimicrobial stewardship (AMS) counseling of the responsible physician.

METHODS

Participants were 155 consecutive adult inpatients with SSTI and good quality clinical samples submitted to the microbiology laboratory from April 2016 to January 2017. Results of the rapid test and AMS recommendations were phoned through to the responsible physician. The comparison group was a historical cohort.

RESULTS

Most SSTI were surgical wound infections (41.3% vs 38.1% for the intervention and comparison groups respectively) followed by diabetic foot (14.2% and 18.1%), abscesses (13.5% both) and cellulitis (12.9% both). Isolated microorganisms were mostly Gram-negative bacilli (two-thirds), followed by Staphylococcus aureus (SA). The ratio methicillin-susceptible SA (MSSA) to methicillin-resistant SA (MRSA) was 4:1. Improvements in the intervention cohort were: DOT (22.0 vs. 24.3 days, p = 0.007), treatment duration per SSTI episode (14.1 vs. 15.0 days, p = 0.072), treatment cost (433.1 vs. 533.3 €, p = 0.039), length of stay (18.6 vs 20.7 days, p = 0.031), related mortality (1 vs. 4 patients, p = 0.022) and Clostridium difficile infection (CDI) (4 vs. 8 patients, p = 0.050). In 48 cases (31.4%) in the intervention group, advice was given to improve empiric antibiotic treatment.

CONCLUSION

This type of program could help adjust antibiotic treatment when inappropriate, reducing antibiotic use and costs, length of stay, CDI and related mortality.

Disease-based antimicrobial stewardship: a review of active and passive approaches to patient management

Although new antimicrobial stewardship programmes (ASPs) often begin by targeting the reduction of antimicrobial use, an increasing focus of ASPs is to improve the management of specific infectious diseases. Disease-based antimicrobial stewardship emphasizes improving patient outcomes by optimizing antimicrobial use and increasing compliance with performance measures. Directing efforts towards the comprehensive management of specific infections allows ASPs to promote the shift in healthcare towards improving quality, safety and patient outcome metrics for specific diseases. This review evaluates published active and passive disease-based antimicrobial stewardship interventions and their impact on antimicrobial use and associated patient outcomes for patients with pneumonia, acute bacterial skin and skin structure infections, bloodstream infections, urinary tract infections, asymptomatic bacteriuria, Clostridium difficile infection and intra-abdominal infections. Current literature suggests that disease-based antimicrobial stewardship effects on medical management and patient outcomes vary based on infectious disease syndrome, resource availability and intervention type.

The role of methicillin-resistant Staphylococcus aureus in skin and soft tissue infections

PURPOSE OF REVIEW

Methicillin-resistant Staphylococcus aureus (MRSA) has become a major public health issue worldwide over the last years. MRSA is frequently implicated in the development of skin and soft tissue infections, leading to significant increases in morbidity, mortality and overall healthcare costs.

RECENT FINDINGS

In order to face the threat of MRSA, major changes in clinical management of skin and soft tissue infections are required. The identification of populations at risk for the acquisition of infections due to MRSA, together with the improvement of the diagnostic techniques, is paramount. Moreover, a number of new antimicrobials with activity against MRSA have been recently developed and approved for the treatment of skin and soft tissue infections, however, the use of the new drugs in the wide clinical practice remains limited.

SUMMARY

We reviewed the current epidemiology of MRSA in skin and soft tissue infections, with particular focus on implications for clinical management. The potential role of new antibiotic options against MRSA infections is also discussed.

Antimicrobial stewardship in the treatment of skin and soft tissue infections

BACKGROUND

Research on treating skin and soft tissue infections (SSTI) has shown improved patient outcomes with effective pharmaceutic prescribing. Antimicrobial stewardship programs can reduce consequences of broad-spectrum antimicrobial administration in SSTI treatment.

METHODS

Prospective and historic control data were collected during two 7-month periods. Intervention consisted of implementing a new SSTI evidence-based treatment algorithm and provider education, including calls and medical record notes targeted at physicians.

RESULTS

Of 412 patients, 76 and 86 were found eligible from the historic and intervention groups, respectively. The intervention group had a higher prevalence of appropriate antibiotic usage (33% vs 19%, respectively; P = .04). There was a lower median number of days from intravenous antibiotic therapy to oral conversion (3 vs 5; P < .0001) and a lower median number of days of antipseudomonal antibiotic use (3 vs 5; P = .03) in the intervention group, respectively. The intervention group also had fewer documented SSTI treatment complications (1% vs 8%, respectively; P = .04). The positive outcomes outlined demonstrate potential impacts made from the use of multidisciplinary antibiotic stewardship initiatives.

CONCLUSIONS

Appropriate use of antimicrobial agents under the direction of an antimicrobial stewardship program can lead to improved outcomes for patients being treated for SSTIs.

Clinical impact of non-antibiotic recommendations by a multi-disciplinary antimicrobial stewardship team

INTRODUCTION

The multi-disciplinary antimicrobial stewardship team at the study hospital conducts prospective review and feedback on all inpatient orders of piperacillin-tazobactam and carbapenems. In addition, the team provides non-antibiotic recommendations (i.e. additional investigations and infectious disease reviews). This study aimed to describe the impact of these recommendations on patient outcomes.

METHODS

Patients on carbapenem and piperacillin-tazobactam who received at least one non-antibiotic recommendation between January 2012 and August 2014 were included in this study. Acceptance and rejection of non-antibiotic recommendations by the managing physician were compared. The primary outcome was 30-d mortality.

RESULTS

Non-antibiotic recommendations were made in 166 patients. There were no differences in baseline characteristics between patients for whom recommendations were accepted and patients for whom recommendations were rejected. Thirty-day mortality (18.0% vs. 34.5%, P = 0.02) was significantly lower in patients who had at least one non-antibiotic recommendation accepted. Multi-variate analysis found that Charlson's comorbidity score [odds ratio (OR) 1.20, 95% confidence interval (CI) 1.03-1.42, P = 0.03], APACHE II score (OR 1.10, 95% CI 1.01-1.19, P < 0.01), hepatobiliary source of infection (OR 10.19, 95% CI 1.44-72.13, P = 0.02) and acceptance of at least one non-antibiotic recommendation (OR 0.39, 95% CI 0.17-0.88, P = 0.02) were independently associated with 30-d mortality.

CONCLUSIONS

During prospective review and feedback of piperacillin-tazobactam and carbapenems, acceptance of non-antibiotic recommendations was found to be associated with a reduction in 30-d mortality.

The Clinical Relevance of Antibiotic Resistance: Thirteen Principles That Every Dermatologist Needs to Consider When Prescribing Antibiotic Therapy

Antibiotics are commonly used by dermatologists in clinical practice, primarily because of the overall track record of favorable efficacy and safety with the most commonly used agents. During the past decade, increased attention has been given to the problems associated with antibiotic resistance. This article summarizes important principles gleaned from the continued efforts of the Scientific Panel on Antibiotic Use in Dermatology; other groups working diligently in this area, such as the Centers for Disease Control and Prevention and the Canadian Antimicrobial Resistance Alliance; and from the published literature.

Outcomes Associated With Antimicrobial De-escalation of Treatment for Pneumonia Within the Veterans Healthcare Administration

De-escalation, an antimicrobial stewardship concept, involves narrowing broad-spectrum empiric antimicrobial therapy based on clinical data. Current health outcomes evidence is lacking to support de-escalation. Studying Veterans Healthcare Administration pneumonia patients, de-escalation was associated with improved length of stay without affecting 30-day readmission or 30-day Clostridium difficile infection rates.

Antimicrobial stewardship program in a Malaysian district hospital: First year experience

Backgrounds & Objective:

Antimicrobial resistance is an alarming public health threat that requires urgent global solution. Implementation of antimicrobial stewardship program (ASP) is an essential practice element for healthcare institutions in gate-keeping judicious antimicrobial use. This study highlighted the development, first year experience, and result of the implementation of ASP utilizing persuasive and restrictive approaches in a Malaysian district hospital.

Methods:

An observational study was conducted between January 2015 to December 2015 on implementation of ASP among hospitalized inpatients age 12 years old and above.

Results:

Recommendations were provided for 60% of cases (110 patients) with the average acceptance rate of 83.33%. Majority of the interventions were to stop the antimicrobial therapy (30.3%), and the most common audited antimicrobials was Piperacillin/Tazobactam (25.5%), followed by Meropenem (11.82%), Amoxicillin/Clavulanate and Vancomycin (8.18%) respectively. The concordance rate towards authorization policy was increased in 2015 (71.59% of cases) as compared before the implementation of ASP in 2014 (60.6% of cases). Restrictive enforcement under ASP had been shown to improve significantly adherence rate towards antimicrobials authorization policy (p-value: 0.004).

Conclusion:

ASP was successfully implemented in a district hospital. Future studies on its clinical outcomes are important to evaluate its effectiveness as well as focus on the improvement to the pre-existing strategies and measures.

Hot topics in the diagnosis and management of skin and soft-tissue infections

Eighteen hot topics regarding the diagnosis and management of skin and soft-tissue infections (SSTIs) were selected and reviewed by members of the SSTI Working Group of the International Society of Chemotherapy (ISC). Despite the large amount of literature available on the issue selected, there are still many unknowns with regard to many of them and further studies are required to answer these challenging issues that face clinicians on a daily basis.