Implementing a Laboratory Initiated Antimicrobial Reflex Protocol as Rapid Response for Multidrug Resistance Organisms

In today’s pace of the microbiology lab and medicine practice, ‘time’ becomes increasingly critical. Every fleeting moment between diagnosis of an infection and empirical treatment, to identifying the infective organism and implementing the appropriate treatment can significantly impact patients' clinical outcome. To delve into specifics, take carbapenemase producing Enterobacterales as an example. How readily can facilities access ceftazidime/avibactam, meropenem/vaborbactam, or imipenem/relebactam testing on KPC producing strains? And what are the criteria for suspecting an OXA48, the following confirmatory method, and reflex agents? Especially when Class D β-lactamases are not inhibited by all clinically available inhibitors.

The essence of a laboratory initiated antimicrobial reflex protocol is its proactivity, negating the delays and ensuring patients are in appropriate and on the most effective therapeutic path sooner. Furthermore, this methodology aids in continually updating and refining our understanding of local resistance trends and interventions.

Defining the Testing Criteria

Accuracy and precision should not be compromised in a reflex protocol. Testing must be timely, and their parameters should align with the evolving antimicrobial resistance. As described in my previous article ‘Defining, Screening, and Analyzing: A Tri-Pillar Laboratory’s Approach for Improving Antimicrobial Resistance Workflow,’ defining the criteria is the most important variable of the protocol. Organisms for which the protocol would apply, infection site, organism’s phenotypic patterns, and resistance marker testing if appropriate, are important functional and defining criteria.

In more detail, for pathogens like P. aeruginosa, what defines it as ‘Multidrug Resistant (MDR),’ ‘Difficult-to-Treat (DTR),’ or what pattern prompted us to suspect a VIM-carrying strain? Establishing these clear guidelines ensures a multifaceted and comprehensive approach to the vast spectrum of microbial challenges and allows us to standardize, reproduce and harmonize laboratory testing protocols.

The Leading Role of Microbiology Labs

Microbiology labs, although commonly not a source of research, the diagnostics, and clinical applications we implement, are sources of actionable data, and it is important we leverage it for driving conversations around antimicrobial strategies. Our data, often structured collated, offers a treasure trove of insights. From understanding local resistance patterns to gauging the effectiveness of new antimicrobial agents, labs are repositories of invaluable knowledge.

It is time for microbiology labs to take in a leadership roles and steering these discussions. Decisions anchored in their findings, experiences, and expertise will inherently be more informed, nuanced, and effective. This initiative-taking involvement ensures that strategies are not just based on generic, global data but are tailored to local needs, making them exponentially more impactful.

Significance of Validation and In-House Testing Availability

In the current microbiology lab, adaptability and foresight are paramount. As new antimicrobial agents emerge on the horizon, understanding their applications, indications, and performance, besides immediate in-house testing becomes a necessity, especially in areas with high resistance prevalence. The dangers of solely relying on reference labs or global surveillance data are multi-fold, leading to potential misinterpretations and missed opportunities, which will negatively impact patient’s outcome.

In-house testing, particularly when under the umbrella of a reflex protocol, ensures agility. It provides tailored insights that consider the unique bacterial population, resistance, and patient demographics of a region, ensuring that our institutions are consistently ahead of the curve in dealing with the threat of antimicrobial resistance.

We Must Test and Implement New Antimicrobial Agents

During the debates about the shrinking pipeline of novel antimicrobial agents, the challenge for accessing new antimicrobials often remains unaddressed. New antimicrobial costs and unfamiliarity with its applications and mechanism of action restrict or delay their adoption. The problem is not just a lack of new agents, it is our role to be proactively patient care activists promoting the internal review of new agents and their testing for data collection and surveillance. Not all new antimicrobials need to be available in the hospital’s pharmacy formulary, and this is also the role for good stewards, but we must assist our healthcare colleagues in identifying the right niche for each agent. But hospital formulary and lab testing capabilities are two different fronts. It should not be a requisite to have a new antimicrobial agent in our pharmacy’s formulary, for the lab to be able to perform internal testing for local surveillance purposes, and even to validate. This data does not necessarily have to be available in the patient chart, but available when needed.

When faced with a new agent not in our hospital formulary, should labs avoid testing? Emphatically, no. Introducing these agents into reflex protocols allows for data accumulation, offering a clearer picture of their efficacy against local organisms and resistances. This data is not just for immediate clinical application; it is an investment into the future, shaping therapeutic strategies for years to come.

Conclusion

In the evolving threat of antimicrobial resistance, our testing capabilities and implementation for new antimicrobials have become our strongest asset. The diverse challenges, exemplified by the rise of carbapenemase producing Enterobacteriaceae, MDR A. baumannii and P. aeruginosa, only highlight the need for a more proactive approach. A reflex protocol is not just about improving patient outcomes in the now; it is a visionary step forward.

Microbiology labs, by taking the lead in decision-making processes and driving conversations based on their invaluable data and experience, they can spearhead a revolution in antimicrobial testing and management. With their guidance, we do not just aim to stay abreast of this threat; we aim to stay ahead, always prepared for the next challenge.