Diagnostic stewardship and antimicrobial resistance

By Hannah Liu
QIAGEN Medical Affairs – Infectious Diseases

Antibiotics have revolutionized the field of medicine. Diseases that were once deadly, like the common flu, are now treatable. Antibiotics have paved the way for life-saving surgeries and transplants.

However, along with this powerful tool comes great responsibility. With the development of each antibiotic, pathogens evolve strategies to thwart their effects in a process known as antimicrobial resistance (AMR). By 2050, it is predicted that death by antibiotic resistant infections will surpass that of cancer (1). 

Fortunately, diagnostic stewardship and specifically syndromic testing can be instrumental in fighting this ongoing threat.

What is antimicrobial stewardship?

According to the CDC, about 30% of antibiotics prescribed in US acute care hospitals are unnecessary or suboptimal (2). These errors can arise when antibiotics are given when not needed, distributed at the incorrect dose, continued when no longer necessary, or the wrong antibiotic is given to treat an infection. 

Antimicrobial stewardship is the systemic effort to optimize the use of antimicrobials to enhance patient outcomes while minimizing the rise of antibiotic resistance. It is a dynamic dance of using antibiotics when necessary to save lives while limiting any extraneous antimicrobial therapy. It involves selecting the right therapy, dosing, route and duration and discontinuing the antibiotic when it has served its purpose.

To properly use antibiotics, you have to accurately and rapidly identify the microbe that is causing symptoms. This is where rapid diagnostic testing can potentially interface into antimicrobial stewardship programs to help providers determine exactly what pathogen is causing the infection to select the most optimal therapy. 

Diagnostic stewardship –  getting the right test to the right patient at the right time

Diagnostic stewardship is the upstream lever that runs the machine of antibiotic distribution. It is the coordinated guidance and interventions to improve the appropriate use of microbiological diagnostics and guide therapeutic decisions. When we get the right test to the right patient at the right time, this can finetune the accuracy of our diagnosis. This in turn reduces unnecessary antibiotic use.

Diagnostic stewardship means promoting appropriate, timely diagnostic testing, proper specimen collection and pathogen identification, and timely reporting of accurate results to guide patient treatment. Rapid diagnostic testing has recently been shown to improve the time to effective antimicrobial therapy, reducing unnecessary treatments, and shortening length of hospital stay (3). In one 2015 study, the greatest benefits in rapid multiplex PCR testing were seen when combined with antimicrobial stewardship programs (4).

Does the test have a high enough sensitivity and specificity? Are there checkpoints to make sure tests aren’t accidentally given to the wrong person? Will test results be available in time to make a difference? These are all questions that diagnostic stewardship asks. Fortunately, we have many tools to help, one of which is syndromic testing.  

The role of Syndromic Panels in combating AMR

Rapid identification of pathogens is crucial in helping administer the proper therapies in an actionable timeframe. Even if a therapy has started, studies show that stopping unnecessary therapy early is associated with lower rates of drug resistance (5).

Syndromic panels are a matter of knowing your enemy, so that you can wield the most suitable weapons, and mount a defense as quickly as possible. Syndromic multiplex panels save time by testing for multiple pathogens at once. When diagnosing a symptomatic disease, time is of essence--selection of the right test for the right patient as little impact on clinical decisions unless the results are not reported in time (5).

All of these factors help to reduce the overutilization of antibiotics by narrowing the precision of diagnosis.

Concluding thoughts

The gravity of antimicrobial resistance—living in a world where bacteria can no longer be killed by modern medicine—calls for a rapid response.

Antimicrobial and diagnostic stewardship can be the solution. With the right test given to the right patient at the right time, aided by syndromic testing, we can take control in the fight against antimicrobial resistance.