Fighting antimicrobial resistance in pet UTIs

Photo: Vitalii Vodolazskyi/Adobe Stock

Urinary tract infections (UTIs) are a common health problem in dogs and cats. Veterinarians often treat these infections with antibiotics, but over time, this widespread use contributes to antimicrobial resistance (AMR). As resistant bacteria become harder to kill, both animal and human health face growing risks. A recent study published in Animals highlights the importance of responsible antibiotic use, guided by international treatment guidelines, in slowing this dangerous trend.

In this study, researchers evaluated hundreds of bacterial samples from dogs and cats with UTIs. They focused on identifying the bacteria involved, measuring antibiotic resistance, and tracking multidrug resistance (MDR), which is a more severe form of AMR where bacteria resist multiple types of antibiotics. Almost half the patients had recurrent or upper UTIs, and many infections involved Escherichia coli, a common pathogen in both pets and humans.

The findings raised serious concerns. Seventy-five percent of the bacterial isolates showed some resistance to antibiotics, and over one-third qualified as multidrug-resistant. Many of these bacteria resisted first-line antibiotics, including penicillins and fluoroquinolones, which veterinarians often use to treat UTIs. These trends show how quickly bacteria adapt and why current prescribing habits need to change.

To combat this problem, the hospital adopted treatment guidelines from the International Society for Companion Animal Infectious Disease (ISCAID). These guidelines promote evidence-based decisions when diagnosing and treating UTIs. Instead of automatically reaching for antibiotics, veterinarians first perform tests to identify the infection and choose the most effective, narrow-spectrum drug when necessary. They avoid overusing powerful drugs meant for more serious infections.

After applying these guidelines for 30 months, the hospital saw real progress. Rates of multidrug resistance dropped significantly over time. Cases involving prior antibiotic use, especially fluoroquinolones and broad-spectrum penicillins, showed the strongest links to MDR. As veterinarians prescribed these drugs less often and used them more selectively, they reduced the pressure that drives resistance.

This shift demonstrates the power of antimicrobial stewardship by choosing antibiotics carefully and only when truly needed. By following guidelines, veterinarians not only improved care for their patients but also helped protect the effectiveness of antibiotics for the future. This approach mirrors strategies used in human medicine, especially for infections like UTIs that frequently lead to antibiotic prescriptions.

The study also emphasizes the connection between pet and human health. Since dogs and cats live in close contact with people, they can carry and share resistant bacteria, especially strains like MDR E coli. Reducing resistance in animals helps limit the risk of transferring these dangerous bacteria to humans. This forms part of the broader One Health initiative, which recognizes that human, animal, and environmental health are deeply interconnected.

This approach requires time, teamwork, and consistency. At the hospital, clinicians and microbiologists worked together to guide treatment choices and educate staff about the risks of AMR and the importance of guideline-based care. While not all veterinary settings may have this level of coordination, the study shows that change can begin in one hospital and expand outward. By following science-based antibiotic guidelines, veterinary teams can protect their patients and the public, reduce unnecessary antibiotic use, and preserve treatment options. As resistant bacteria continue to pose a global threat, efforts like these show that responsible prescribing can make a meaningful difference, not just for pets but for everyone.

Ava Landry is a 2026 PharmD candidate studying veterinary pharmacy at the University of Connecticut in Storrs.

Reference

1. Scarpellini R, Piva S, Monari E, et al. Antimicrobial resistance in companion animals: a 30-month analysis on clinical isolates from urinary tract infections in a veterinary hospital. Animals. 2025;15(11):1547. doi:10.3390/ani15111547