New testing and the future of antibiotic stewardship
By Matt Phillion
Antibiotic-resistance continues to be a challenge for the healthcare industry, as medical and public health professionals look for ways to combat it even as more multiple-drug resistant (MDR) bacteria, viruses, and fungi emerge.
Affordable genetic testing is a relatively new option for battling MDRs, offering ways to improve testing and practices for antibiotic stewardship.
Talk of stewardship programs can sometimes devolve into buzzwords, notes Dr. Joel Diamond, CMO of Aranscia. Competing interests, litigation, and varying pressures can make locking down a true stewardship mindset difficult.
“I don’t think people have the right tools,” says Diamond. “It’s hard to talk about stewardship when you have a lot of pressure to prescribe antibiotics.”
As a physician in private practice, Diamond says, he would do everything he could to not give antibiotics unnecessarily. But the population being treated can be uniquely challenging: in a nursing home with very sick, non-communicative, high-risk patients, what other choice is there?
“I think people feel like they’re between a rock and a hard place. We’re on the right track, and people are cognizant of these challenges. COVID has driven it home. We learned how to better isolate people, reduce transmissions from infections from one patient to another, and that’s a big part of it,” says Diamond. “Thinking about it not from a singular problem but as a population health issue has been helpful.”
But the industry tends to rely on old tools, Diamond notes. Using traditional cultures and century-old techniques leaves a lot of improvement off the table.
“I’m always amused showing people the timeline of microbiology in the world. It’s hard to believe that the techniques we use today were invented in over a century ago and we’re still using them,” he says.
PCR tests became the talk of the town during COVID, but even this isn’t new technology.
“PCR was developed a few decades ago. The Nobel Prize was awarded for it,” says Diamond. “And we’re still saying this is new technology.”
Economics and change
There is still a perception that these newer tests are cost-prohibitive, Diamond notes, but the benefits can outweigh the current cost. In addition, the more the tests are used, the more the cost will be driven down.
“Laparoscopic surgery was more expensive when it first came around, but use drove the cost down, and once the industry knew the benefits and its impact on the cost of care, it became ridiculous not to use it,” says Diamond.
The economics of diagnosing and treating infections haven’t been fully figured out yet by the industry, and so there’s a bit of a lag until incentives line up. The benefits are already in plain sight, though.
“Take reporting infections in nursing homes, for example. Right now, it’s just the number and types of infections, but other important factors are harder to measure: how quickly do you get people off antibiotics if the culture is negative? What is the time from diagnosis to correct antibiotic?” says Diamond. “It requires more time for organizations on recording and reporting data.”
Economics aside, the benefits to using molecular techniques over cultures go beyond just modernizing testing choices. Take the turnaround time for starters.
“Say you’ve got a patient in a nursing home with a suspected UTI. I’m a family doctor, so I’ll get a call from the nursing home on the weekend. These are not like other calls. The patients are often stroke patients or living with dementia, so it’s not: the patient is complaining about painful urination and so on,” says Diamond. “It’s more along the lines of the patient isn’t acting right and the nurse thinks it might be an infection.”
You’re not supposed to treat patients who have asymptomatic bacteria, and you should only treat with antibiotics if it’s truly an infection, Diamond says. So the doctor orders a culture, which can take 48-72 hours to come back.
“That period is the witching hour for a patient getting septic and going to the hospital,” says Diamond. “The physician asks: do I use a ‘strong’ antibiotic because they’re sick? And what does strong even mean? And in a few days, you get a report that says it was the wrong antibiotic, so you change to a different one and they were exposed to an antibiotic they didn’t need, or the culture comes back as non-bacterial.”
There are infinite combinations of ways this can be an imperfect and impractical solution, which is where looking at the DNA footprint of the organism is a no-brainer, Diamond explains.
“You know what the organism is or isn’t and you get the results back in the time it takes to transport the sample,” says Diamond.
That turnaround time can’t be overvalued as a contribution, he says.
“From the time the accumulated time from when you suspect a person has an infection, put them on the correct antibiotic and take them off the antibiotic if they don’t need it can be reduced by two or three days, which is a huge step in reducing resistance,” he says.
Looking for patterns
Molecular testing, Diamond notes, enables the ability to identify resistant genes in the organism. This can be very useful in populations like nursing homes where resistance patterns can escalate quickly and cause harm.
“For example, in a unit in a nursing home, you might start to see a resistance pattern in that population. You can then select antibiotics based on recognizing an increase in resistance by the organism,” says Diamond. “You might use a different antibiotic as you’re trying to stave off that infection.”
Without that kind of insight, it’s not even attempting a best guess. Best guesses can become increasingly wrong as resistance patterns are not known to the physicians involved.
“It’s not even a stab in the dark, it’s making a bad choice they wouldn’t even know was a bad choice,” says Diamond.
Diamond relates a story he heard recently where a facility was seeing a bacterial infection resistant to the “stronger” antibiotic choice, essentially making it 50% effective. The staff thought they were using the better antibiotic, but in fact it was weaker against this particular organism. Taking the guesswork out of how to prescribe can have a huge impact.
While the industry can’t dive headfirst into change, using molecular testing to help identify populations with more high-risk patients, recurrent infections is a good place to start, and that additional use can help feed into fixing the economic problem getting in the way of wholesale change.
“The cost will come down as the volume increases, like anything else,” says Diamond. “Certainly say, a 34-year-old woman with an uncomplicated bladder infection may not need genetic testing for her issue, but we can help organizations find the right populations for this and with more widespread use and bigger, more extensive studies, we can show the return on investment.”
As with any change or new adoption of technology, the question of who pays for and how to incentivize it comes up.
“It has to be a part of bigger incentives for true stewardship,” says Diamond. “Instead of just talking stewardship, let’s say here is what we want to measure, here is what we want to reduce, the time from suspected infection to the right antibiotic. If you can measure that and we give you the tools to measure it, then a molecular testing technique can be made worthwhile.”
It will require a culture shift and sea change to advance the techniques of choice, though. Diamond notes that for physicians, they’re not ordering the test itself so much as the result.
“We kind of keep doing what we’ve been doing because we believe it’s good enough, or we don’t know about an alternative. Doing a culture has been around forever, so a physician isn’t necessarily saying I don’t want a standard urine culture, I want a new molecular test,” says Diamond. “I think once people understand they can order this test and it comes with information about resistance genes and other data, a lightbulb goes off.”
Again, these tests aren’t new, they just aren’t yet current practice.
“We’ve been ordering DNA tests for almost every other infection for a while now—hepatitis, viral infections, COVID, Lyme disease, cancer. Why wouldn’t we extend this all the way through?” he says
If it opens the door to determine the right meds for the right people, it becomes routine. And given the razor’s edge we live on when it comes to resistant organisms, better testing can go a long way to keeping patients safer.
“It’s scary how close we are. We get saved by the skin of our teeth when it comes to different staph infections, a new fungus,” says Diamond. “Once it’s past, we slip back, and it’s no longer scary, and that’s part of the problem.”