Prudent Antimicrobial Use in an Antimicrobial-Resistant World

In a perfect world, antimicrobials used in animals would be unrelated to those used in humans. But we are not in a perfect world. All of the antimicrobial drug classes that we use clinically in companion animals are also used in humans. As a result, we have to be cognizant of the potential impact of veterinary antimicrobial use on public health while maintaining a high level of patient care.

When not presented with a sick animal, or when not working as a veterinary clinician, it can be easy to say “Do not use important drugs in animals.” I have had interesting debates with colleagues, mainly from northern Europe, who say that we should never use such drugs as carbapenems in animals. Although I understand their point—and completely agree that veterinary use of drugs that are used to treat serious infections in humans must not compromise human health—I also know that I have many patients that had multidrug-resistant bacterial infections and are alive today because we used those drugs. Further, although any use can lead to resistance, does rare and prudent use in animals constitute any real risk for public health when we consider the tremendous use of these drugs in humans? I don’t think so, but admittedly, it’s a slippery slope. As we encounter more and more resistant bacteria, we will have more and more pressure to use subsequent generations of antimicrobials.

So, how do we find a balance?

Antimicrobial stewardship is the key. We need to make sure that we use antimicrobials (all antimicrobials) properly. We need to take special care with drug classes that are of particular importance in humans. Veterinarians need to take the lead here—because if we do not, someone else might. In some European countries, use of various drug classes in companion animals is banned. That raises the specter of having a patient with a life-threatening infection that would probably respond to a specific antibiotic but would instead perish because use of the required drug is banned in animals. Whether that will happen in other countries is hard to say, but it is far from impossible. If we show that we are addressing the issue, perhaps we can stem the tide of resistance and pressures to restrict access to antimicrobials.

In an attempt to help lead the field, Clinician’s Brief is instituting an antimicrobial stewardship policy, adapted from one recently launched by the Equine Veterinary Journal. Our new policy states:

Authors who provide antimicrobial treatment recommendations must consider the potential impact of veterinary drug use on public health. In particular, authors should avoid recommending extralabel use of fluoroquinolones and extended-spectrum b-lactam antimicrobials (eg, third- or fourth-generation cephalosporins) or recommending drugs such as carbapenems, glycopeptides, and oxazolidinones used for treatment of multidrug-resistant pathogens in humans. If use of any of these is recommended, there must be specific mention of the relevant issues, and evidence supporting the recommendation must be provided.

This policy focuses on careful consideration, not prohibition, and we recognize that there are certainly instances when these drugs are clinically indicated. Authors can still recommend extralabel use of fluoroquinolones, third-generation cephalosporins, and use of other classes such as carbapenems; however, those recommendations will have to be justified, and those justifications will be scrutinized. As such, empirical use of those options is unlikely to appear as a recommendation in this publication. And that’s a good thing.

They will continue to be mentioned for situations where they are needed, such as infections caused by extended-spectrum b-lactamase (ESBL) producing Gram-negative bacteria. That’s a good thing too. It’s difficult to find a balance between patient health and public health, between the ability of veterinarians to use drugs off-label and efforts to restrict that, and between giving authors the freedom to make recommendations while trying to fulfill principles of antimicrobial stewardship.

Bacteria are evolving, and so must we. This is perhaps a small step, but it is an important one nonetheless.