Urinalysis, bacterial culture, and antimicrobial susceptibility in cats with suspected urinary tract infection

Abstract

Urinary tract infections (UTI) in cats represent a diagnostic challenge in clinical practice, particularly because they present with the same clinical signs as feline lower urinary tract disease. This study aimed to analyze the findings of urinalysis, urine culture, and antimicrobial susceptibility testing in cats with suspected UTI, in order to understand the microbiological profile and bacterial sensitivity to the antimicrobials tested. A total of 86 urine samples from cats showing clinical signs compatible with UTI were analyzed. The evaluated data included sex, presence or absence of leukocyturia, haematuria, proteinuria, and urinary pH, as well as urine culture results and antimicrobial susceptibility profiles. The mean age of the animals was 8.7 years, with a predominance of females. Leukocyturia was observed in 86.05% of the cases, hematuria in 66.28%, and proteinuria in 73.26%. In 43.2% of the samples, the urinary pH values were below the laboratory's reference range (5.0-7.0). Urine culture was positive in 24.42% of the cases, with Escherichia coli being the most frequently isolated bacterium (71.43%), followed by Enterococcus faecalis, Proteus mirabilis, Staphylococcus pseudointermedius, and Enterococcus spp. E. coli showed resistance to ampicillin and amoxicillin in 40% of the samples. E. faecalis exhibited a variable sensitivity pattern but showed 100% sensitivity to ciprofloxacin and sulfamethoxazole-trimethoprim. The findings reinforce that, although essential, urinalysis should not be used alone for the diagnosis of UTI. The low frequency of positive cultures, along with the diversity in resistance profiles, highlights the importance of microbiological confirmation and antimicrobial susceptibility testing, which are crucial for therapeutic success, responsible antibiotic use, and combating bacterial resistance.