Diagnostic stewardship: The role of the lab in antimicrobial resistance (AMR)

Antimicrobial resistance (AMR) has become a critical global health threat, endangering the effectiveness of essential antibiotics and other antimicrobial agents.¹ The rising prevalence of resistant infections leads to longer hospital stays, higher medical costs, and increased mortality.² AMR undermines progress in modern medicine, making even routine surgeries and treatments more dangerous.³

The ever-increasing resistance to antimicrobial treatments stems from their inappropriate use, and the limited pipeline of new anti-infective agents is magnifying this problem. Every year, AMR is associated with almost 5 million deaths globally. And by 2050, it is predicted that this could rise to approximately 8-10 million deaths annually worldwide.^1,4-5

Today, healthcare organizations are establishing antimicrobial stewardship programs to promote and monitor the appropriate use of antibiotics with the hopes of reducing AMR. Diagnostic stewardship strategies are recommended as a complementary approach to antimicrobial stewardship. Diagnostic stewardship guides clinicians in selecting the appropriate tests at the right time to inform and improve patient treatment.⁶

By supporting diagnostic stewardship, lab leaders can help optimize the use of diagnostics to enhance antibiotic prescribing and clinical decision making, decrease unnecessary costs, and positively impact patient care.^6-8

Diagnostic laboratories play a pivotal role in promoting diagnostic stewardship and combating AMR by enabling precise and timely identification of the causative pathogen and associated resistance. By supporting targeted treatments, diagnostic laboratories are essential in curbing the global AMR crisis and improving patient care.

However, many healthcare organizations worldwide have not fully embraced diagnostic stewardship due to several challenges preventing its proper execution. These challenges often stem from barriers and constraints that impede the optimal use of microbiological diagnostics, such as:⁸

• Lack of staff awareness and training
• High costs
• Lack of reimbursement for microbiological diagnostic testing 
• Supply chain limitations for consumables 
• Difficulty in transportation of samples
• Limited lab quality assurance

These challenges are especially difficult to overcome in low and middle-income countries (LMICs). In the African region and other low-resource countries, where the populations experience a high prevalence of infectious diseases, overuse of antibiotics is a significant problem due to outdated facilities, lack of expertise, and shortage of effective medicines.⁹ Therefore, global collaboration is a major need to ensure that AMR is addressed worldwide, especially in these regions.

To address these challenges, lab leaders have the opportunity to incorporate diagnostic stewardship strategies within the testing pathway (ordering, collecting, processing, reporting, and interpreting results).^{6-8, 10-12}

• Improving knowledge and decreasing cognitive bias: Educating clinicians and laboratory staff to strengthen their understanding of testing principles and result interpretation. 
• Best practice alerts: Notifying clinicians, via electronic health records (EHR), when tests are appropriate and when they are not recommended. 
• Ease of ordering: Adjusting the ease of access to specific tests in EHRs to either encourage or discourage use.
• Removal of tests: Removing specific tests from EHRs to reduce the ordering of unnecessary or low-value tests. 
• Inclusion of tests: Including tests in EHRs to promote recommended diagnostic tests based on clinical factors.
• Selective testing: Rejecting or deferring testing when the sample is inadequate or contaminated.
• Selective reporting: Providing clinicians with specific portions of the results that are of highest value.
• Monitoring adherence to best practices: Reviewing and monitoring trends such as test utilization rates and quality indicators.
• Providing feedback: Informing clinicians on their test utilization rate to ensure best practices are maintained and to encourage improvement.

Implementing these diagnostic stewardship concepts can improve diagnostic accuracy and decrease diagnostic errors. Through diagnostic stewardship, labs can provide critical information to clinicians for correctly guiding optimal antibiotic treatment, and play a vital role in preventing AMR.

The COVID-19 pandemic underscored the crucial role of clinical laboratories in addressing public health threats, both in terms of providing critical information to guide patient management and data for public health surveillance. Similarly, labs play a vital role in combating the rise of AMR.

Laboratory directors or leaders can support and drive the implementation of diagnostic stewardship strategies by promoting the following:^13-15

1. Promote evidence-based testing: Ensure that laboratory staff follow up-to-date, evidence-based guidelines for antimicrobial susceptibility testing (AST). This involves promoting the use of standardized testing protocols to accurately identify resistant pathogens and provide clinicians with reliable results.

2. Integrate stewardship programs: Work closely with antimicrobial stewardship teams to establish protocols for diagnostic testing that align with the goals of the antimicrobial stewardship program (ASP). This could include implementing guidelines on when to order specific tests, such as culture and sensitivity testing, to minimize unnecessary antibiotic use.

3. Enhance rapid diagnostics: Advocate for the adoption of rapid diagnostic technologies, such as PCR-based assays or MALDI-TOF, that can quickly identify pathogens and their resistance profiles. Faster results can lead to more targeted treatment and prevent the prolonged use of broad-spectrum antibiotics.

4. Provide education and training: Regularly educate laboratory staff and clinicians on the importance of diagnostic stewardship. This includes training on proper test selection, interpretation of results, and the role of diagnostic testing in reducing unnecessary antibiotic use.

5. Support data collection and analysis: Develop systems to track and analyze resistance patterns within the institution or region. Sharing this data with clinicians and stewardship teams can help identify emerging resistant organisms, track trends, and tailor local antibiotic prescribing practices.

6. Implement test utilization management: Establish criteria for appropriate test ordering, ensuring that tests are used efficiently and only when necessary. Laboratory leaders can collaborate with clinicians to reduce unnecessary or redundant tests, which in turn helps to prevent overdiagnosis and the inappropriate use of antimicrobials.

7. Foster collaboration: Foster a collaborative environment between the laboratory, infectious disease specialists, pharmacists, and clinical teams. Regular interdisciplinary meetings can facilitate discussion around test results, treatment plans, and strategies for optimizing antibiotic use.

8. Encourage antimicrobial resistance surveillance: Actively participate in or establish AMR surveillance programs to monitor resistance trends and provide real-time data to support decision-making. By integrating local resistance data into stewardship initiatives, laboratory leaders can help clinicians adjust their prescribing practices in real time.

9. Promote de-escalation of therapy: Encourage diagnostic stewardship practices that support de-escalation of antimicrobial therapy once test results are available, especially for infections initially treated empirically with broad-spectrum antibiotics.

10. Advocate for resource allocation: Secure necessary resources (e.g., staffing, funding, and technology) to ensure that the laboratory can perform advanced diagnostic testing and contribute to effective stewardship efforts.

By taking these actions, laboratory directors can play an integral role in improving diagnostic accuracy, reducing the overuse of antimicrobials, and ultimately contributing to the global fight against AMR.