Peer-reviewed veterinary case report
Mass spectrometry shows many dogs have multiple bacteria in urinary
By Rodrigues Paschoal, Natália et al.·Published in Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]·2025·Department of Animal Production and Preventive Veterinary Medicine, Brazil·View original on PubMed →
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Original publication title: Mass spectrometry-based identification reveals the polymicrobial nature of canine urinary tract infections.
- Species:
- dog
Plain-English summary
A group of dogs with urinary tract infections (UTIs) had their urine samples tested to identify the bacteria causing their symptoms. Out of 389 samples, 170 showed growth of microorganisms, with most being bacteria like E. coli and enterococci. The study found that amoxicillin/clavulanic acid was the most effective treatment, working well for over 70% of the cases. However, there were concerns about antibiotic resistance, with some bacteria showing resistance to multiple drugs. This information can help veterinarians choose the best treatment for dogs with UTIs.
People also search for: dog urinary tract infection treatment · antibiotic resistance in dogs · symptoms of UTI in dogs
Abstract
Canine urinary tract infections (UTIs) are common in veterinary practice and often have a complex etiology. Typically, diagnoses rely on classical phenotypic tests or are limited to identifying the genus of the pathogen. Treatments are frequently administered without prior in vitro antimicrobial susceptibility testing. This study analyzed 389 urine samples from dogs with clinical signs of UTI, collected by cystocentesis, through microbiological culture. Species-level identification of bacteria and yeasts was performed using mass spectrometry, while bacterial isolates underwent antimicrobial susceptibility testing via the disk diffusion method. Of the 389 samples, 170 (43.7%) showed microbial growth, with 192 microorganisms identified. Among these, 98.4% (189/192) were bacteria, and 1.6% (3/192) were fungi/yeasts. The predominant pathogens included Enterobacteria (116/192 = 60%), enterococci (26/192 = 13.5%), and staphylococci (24/192 = 12.5%). Novel pathogens, such as Lactobacillus murinus and Stenotrophomonas maltophilia, were identified as primary agents of canine UTIs. Coinfections commonly involved E. coli with either E. faecalis (5/21 = 23.8%) or S. canis (4/21 = 19%). Amoxicillin/clavulanic acid was the most effective antimicrobial (≥ 70%), followed by amikacin and marbofloxacin (≥ 60%). Observed antimicrobial resistance rates included enterobacteria (18%), enterococci (> 40%), staphylococci (18%), streptococci (30%), Pseudomonas aeruginosa (60%), and other organisms (> 30%). Multidrug resistance affected 18% (34/189) of bacterial isolates. This study highlights the polymicrobial nature of canine UTIs and emphasizes concerns about multidrug-resistant bacteria. These findings contribute to improving molecular diagnostics and monitoring antimicrobial resistance in domestic animals, a critical global issue.
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Search related cases →Original publication on PubMed: https://pubmed.ncbi.nlm.nih.gov/40208563/