Antimicrobial stewardship

Introduction

Antimicrobial resistance (AMR) has emerged as one of the most pressing public health threats of the 21st century. The World Health Organisation (WHO) has declared that AMR is one of the top 10 global public health threats facing humanity.[1] The rapid spread of multidrug-resistant organisms (MDROs) coupled with the diminishing pipeline of new antibiotics, has created a perfect storm, threatening our ability to treat common infections.[2] Antimicrobial stewardship (AMS) programs have been proposed as a key strategy to combat AMR by optimising the use of antimicrobials. This review will explore the current state of AMS, its core elements, challenges, and future directions.

Definition and Goals of Antimicrobial Stewardship

The Infectious Diseases Society of America (IDSA) and the Society for Healthcare Epidemiology of America (SHEA) define AMS as “coordinated interventions designed to improve and measure the appropriate use of antimicrobials by promoting the selection of the optimal antimicrobial drug regimen, dose, duration of therapy, and route of administration.”[3] The primary goal of AMS is to optimise clinical outcomes while minimising unintended consequences of antimicrobial use, such as the emergence of resistance, adverse drug events, and healthcare costs.[4]

Core Elements of Antimicrobial Stewardship Programs

The Centers for Disease Control and Prevention (CDC) has identified seven core elements of successful AMS programs in hospitals and nursing homes: leadership commitment, accountability, drug expertise, action, tracking, reporting, and education.[5] These elements provide a framework for designing, implementing, and evaluating AMS programs across various healthcare settings.

1. Leadership Commitment: Leadership support is critical for the success of AMS programs. Hospital administrators and medical staff leaders must prioritise AMS and provide the necessary resources, including dedicated personnel, financial support, and information technology infrastructure.[6] A formal statement of support from leadership demonstrates a commitment to AMS and helps engage staff at all levels.
2. Accountability: Accountability involves appointing a single leader responsible for program outcomes. This leader, often an infectious diseases physician or pharmacist, should have the authority to manage the AMS program and be accountable for its success.[7] Having a dedicated leader ensures that AMS activities are coordinated and aligned with the program’s goals.
3. Drug Expertise: Drug expertise is essential for the development and implementation of AMS interventions. Pharmacists with infectious diseases training play a key role in providing drug expertise and should be core members of the AMS team.[8] They can assist with the selection, dosing, and monitoring of antimicrobials, as well as the development of clinical guidelines and order sets.
4. Action: Action refers to the implementation of AMS interventions to improve antimicrobial use. These interventions can be either restrictive or persuasive. Restrictive interventions, such as formulary restrictions and preauthorization requirements, limit the availability of certain antimicrobials and require approval from the AMS team before use.[9] Persuasive interventions, such as prospective audits and feedback, involve reviewing antimicrobial prescriptions and providing feedback to prescribers to optimise therapy.[10]
5. Tracking: Tracking involves monitoring antimicrobial prescribing and resistance patterns. AMS programs should have access to data on antimicrobial use and resistance at the institutional level.[11] This data can be used to identify areas for improvement, evaluate the impact of AMS interventions, and benchmark performance against other institutions. Common metrics for tracking antimicrobial use include days of therapy (DOT) and defined daily dose (DDD) per 1000 patient days.[12]
6. Reporting: Reporting involves communicating AMS activities and outcomes to stakeholders, including prescribers, nurses, pharmacists, and hospital leadership. Regular reporting helps maintain engagement and accountability.[13] Reports should include data on antimicrobial use, resistance patterns, and the impact of AMS interventions. Feedback to individual prescribers can also be an effective strategy for changing prescribing behaviour.[14]
7. Education: Education is a critical component of AMS programs. Prescribers, nurses, pharmacists, and patients should receive education on the appropriate use of antimicrobials and the importance of AMS.[15] Education can take many forms, including didactic lectures, web-based modules, and interactive workshops. Integrating AMS principles into the curriculum of health professional schools can also help promote a culture of stewardship.[16]

Challenges and Barriers to Antimicrobial Stewardship

Despite the growing recognition of the importance of AMS, several challenges and barriers remain. One major challenge is the lack of resources, particularly in smaller hospitals and long-term care facilities.[17] Implementing an AMS program requires dedicated personnel, information technology infrastructure, and financial support, which may not be available in resource-limited settings.

Another challenge is the lack of standardization in AMS practices across institutions. While the CDC has provided guidance on the core elements of AMS programs, there is still variability in how these elements are implemented.[18] This variability can make it difficult to compare outcomes across institutions and identify best practices.

Resistance from prescribers is another common barrier to AMS. Some prescribers may view AMS interventions as an infringement on their autonomy or may not see the value in changing their prescribing habits.[19] Engaging prescribers in the development and implementation of AMS interventions can help overcome this resistance.

The lack of new antimicrobials in the pipeline is also a significant challenge for AMS. As resistance to existing antimicrobials continues to grow, there is an urgent need for new drugs to treat MDROs.[20] However, the development of new antimicrobials has slowed in recent years due to economic and regulatory barriers.[21]

Future Directions in Antimicrobial Stewardship

Despite these challenges, AMS has several promising future directions. One area of focus is the expansion of AMS programs beyond the hospital setting. While AMS has traditionally been focused on acute care hospitals, there is growing recognition of the need for stewardship in other settings, such as long-term care facilities, outpatient clinics, and dental practices.[22]

Another area of focus is the use of rapid diagnostic tests (RDTs) to guide antimicrobial therapy. RDTs, such as multiplex polymerase chain reaction (PCR) panels and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry, can quickly identify the causative pathogen and its susceptibility profile.[23] This information can help clinicians optimise antimicrobial therapy and reduce the use of broad-spectrum agents.

The integration of AMS with other healthcare quality improvement initiatives is also a promising strategy. For example, combining AMS with infection prevention and control efforts can help reduce the spread of MDROs and prevent healthcare-associated infections.[24] Collaborating with antibiotic allergy testing services can also help optimize antimicrobial therapy by identifying patients who have been incorrectly labelled as allergic to certain antibiotics.[25]

Finally, there is a need for more research on the effectiveness of AMS interventions and the impact of AMS programs on patient outcomes and healthcare costs. While several studies have demonstrated the benefits of AMS, there is still a lack of high-quality evidence to guide practice.[26] Conducting well-designed, multi-centre studies can help identify best practices and inform the development of evidence-based guidelines for AMS.

Conclusion

Antimicrobial stewardship is a critical strategy for combating the growing threat of antimicrobial resistance. By optimising the use of antimicrobials, AMS programs can improve patient outcomes, reduce healthcare costs, and slow the emergence of resistant organisms. Implementing the CDC’s seven core elements of hospital AMS programs can help ensure the success of these programs. However, several challenges and barriers remain, including a lack of resources, resistance from prescribers, and the need for more research on the effectiveness of AMS interventions.

Despite these challenges, there are several promising future directions for AMS, including the expansion of AMS programs beyond the hospital setting, the use of rapid diagnostic tests to guide therapy, and the integration of AMS with other healthcare quality improvement initiatives. As the threat of antimicrobial resistance continues to grow, it is imperative that healthcare institutions prioritize the implementation of robust AMS programs to ensure the judicious use of these life-saving drugs.

References

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