Molecular isolation of Escherichia coli from vagina samples of cats

Abstract

Escherichia coli (E. coli) is a Gram-negative bacterium which can colonise the reproductive tract of animals as an opportunistic pathogen. Fifty vaginal swab specimens were aseptically collected from adult female pet cats. The specimens were directly plated on nutrient broth then cultured on MacConkey agar and Eosin Methylene Blue (EMB) agar. Isolates were identified with VITEK® 2 Compact system (GN cards), and susceptibility to antimicrobial agents tested with AST (antimicrobial susceptibility testing ) using disc diffusion test, demonstrated the E. coli identity. Additional molecular verification was performed by PCR amplification of 16S rRNA gene. It was found that 35 out of 50 samples (70%) were positive for E. coli, reflecting the high prevalence of this microorganism in the vaginal tract of the studied feline animals. All isolates were identified as E. coli by VITEK® 2. This study aimed to assess the antibiotic sensitivity profile of E. coli isolated from vaginal samples of cats using the disc diffusion method. A total of 35 E. coli isolates were tested against imipenem, ceftriaxone, cefixime, aztreonam, ciprofloxacin, cefotaxime, tetracycline, ceftazidime, and sulfonamide-trimethoprim. The results revealed high resistance rates to all tested antibiotics, indicating multidrug-resistant (MDR) strains. Notably, resistance was observed even to last-resort drugs such as imipenem, highlighting a critical concern for treatment options. This study underscores the need for antimicrobial stewardship and alternative therapeutic strategies to combat resistant E. coli infections in feline medicine. Nonetheless, VITEK® 2 had fast and exact results and proved to be applicable for the routine diagnostic laboratory in small animal diagnostics.