Home » Infectious Diseases » Why polymerase chain reaction diagnostics are key to fighting AMR

Dr Mike Loeffelholz

Vice President Scientific Affairs, Cepheid 

In the fight against antimicrobial resistance (AMR), accurate polymerase chain reaction testing is key to safeguarding antibiotics and improving patient care.

When it comes to treating infectious diseases, the target is constantly shifting as bacteria mutate. This might not be an issue if antibiotics were being developed to keep pace, but the fact is: they’re not.

Polymerase chain reaction technology

“There’s just not a huge pipeline of antibiotics, so we’re left with a relatively small menu of antimicrobials that we can use,” confirms Dr Michael Loeffelholz, Vice President of Scientific Affairs at diagnostics company Cepheid.

“Of particular concern are superbugs. They are resistant to most antimicrobial agents, making infections caused by superbugs difficult or impossible to cure. In their fight against AMR, countries including the UK have launched guidelines that focus on managing superbugs.”

While the discovery of a potential new antibiotic compound earlier this year offers some hope, there is much work ahead, and it will be years before patients see the benefits. So, as the search continues, we need to preserve the precious resources we have — and polymerase chain reaction (PCR) technology has a vital role to play.

Speed and efficiency of PCR testing

Most of us were first introduced to PCR tests during the Covid-19 pandemic. Being swabbed in a remote car park became synonymous with those years, but did any of us give a second thought to what the letters PCR meant?

PCR is a laboratory tool where sections of DNA are reproduced millions, or even billions, of times. The technique, which has been around since the mid-1980s, makes it much easier for scientists to identify even the smallest number of pathogens in the body in a matter of minutes to hours.

This insight ensures healthcare professionals can prescribe the right medication much faster, improving patient care and protecting one of our most valuable assets: antibiotics. 

Without accurate diagnostics, drugs continue
to be prescribed in a ‘best guess’ scenario,
which is why PCR testing is crucial.

PCR for accurate antibiotic prescription

Overuse of drugs is a major contributing factor to AMR. In 2019, the UK set itself an ambitious five-year target to reduce antibiotic use by 15%. Without accurate diagnostics, drugs continue to be prescribed in a ‘best guess’ scenario, which is why PCR testing is crucial.

Studies completed in a sexual health clinic several years ago compared how antibiotics were prescribed when rapid onsite PCR tests were offered versus slower forms of diagnosis. Findings showed that healthcare professionals, who had to wait at least a day for results, often felt compelled to prescribe drugs based purely on the symptoms presented by patients. This meant overuse of antibiotics was common while patients in the early stages of disease or with mild symptoms were falling through the net completely.

Loeffelholz explains: “By doing the PCR right away during their clinic stay, fewer people were put on the antibiotics who were negative, and more people who actually had a sexually transmitted infection were put on appropriate antibiotics.”

Increasing access to PCR testing

PCR testing is being used with increasing frequency for numerous diseases, from respiratory conditions and blood viruses to oncology and sexually transmitted infections. While the initial cost of equipment has been a prohibiting factor in the past, access is now increasing.

“Evidence is driving clinical practice guidelines produced by UK and European agencies and in the US,” confirms Loeffelholz. “We want to look beyond simply what is the cost, but the impact that this causes cost-wise to the whole system and the continuum of patient care.”

Loeffelholz is among those pushing to make PCR testing more accessible in the communities that would benefit most. “We’re looking at decentralisation — testing in sites that are closer to the patients through walk-in clinics and mobile vans where there are high-risk patients with, for example, sexually transmitted infections or hepatitis C.”

The UN anticipate that, by 2050, around 10 million people will die each year as a result of antimicrobial resistance. With few other tools in our arsenal, PCR needs to feature prominently in the fight.

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