Rodrigues Paschoal Natália, Ramos Portilho Fábio Vinícius, Oliveira de Almeida Beatriz, Fagali Arabe Filho Marcelo, Rodrigues Carolina Aparecida, Spessotto Bello Thaís, de Lima Paz Patrik Júnior, Paganini Listoni Fernando José, Garcia Ribeiro Márcio
Department of Animal Production and Preventive Veterinary Medicine, School of Veterinary Medicine and Animal Science (FMVZ), São Paulo State University -UNESP, Botucatu, SP, 18618-681, Brazil.
Braz J Microbiol. 2025 Jun;56(2):1381-1389. doi: 10.1007/s42770-025-01656-3. Epub 2025 Apr 10.
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.
犬尿路感染（UTIs）在兽医临床实践中很常见，其病因通常较为复杂。通常，诊断依赖于经典的表型测试，或者仅限于鉴定病原体的属。治疗常常在没有事先进行体外抗菌药敏试验的情况下进行。本研究通过微生物培养分析了389份通过膀胱穿刺采集的有UTI临床症状的犬尿液样本。使用质谱法对细菌和酵母进行种水平鉴定，而细菌分离株则通过纸片扩散法进行抗菌药敏试验。在389份样本中，170份（43.7%）显示有微生物生长，共鉴定出192种微生物。其中，98.4%（189/192）为细菌，1.6%（3/192）为真菌/酵母。主要病原体包括肠杆菌（116/192 = 60%）、肠球菌（26/192 = 13.5%）和葡萄球菌（24/192 = 12.5%）。新型病原体，如鼠李糖乳杆菌和嗜麦芽窄食单胞菌，被鉴定为犬UTIs的主要病原体。混合感染常见于大肠杆菌与粪肠球菌（5/21 = 23.8%）或犬链球菌（4/21 = 19%）。阿莫西林/克拉维酸是最有效的抗菌药物（≥ 70%），其次是阿米卡星和马波沙星（≥ 60%）。观察到的抗菌耐药率包括肠杆菌（18%）、肠球菌（> 40%）、葡萄球菌（18%）、链球菌（30%）、铜绿假单胞菌（60%）和其他微生物（> 30%）。多重耐药影响了18%（34/189）的细菌分离株。本研究突出了犬UTIs的多微生物性质，并强调了对多重耐药细菌的关注。这些发现有助于改善家畜的分子诊断和监测抗菌耐药性，这是一个关键的全球问题。
