Samples
In this study, 90 cats with one or more urinary clinical signs such as stranguria, haematuria, pollakiuria, inappropriate urination, excessive licking of the genital area and frequent and/or prolonged attempts to urinate were physically examined at the Department of Internal Medicine, Faculty of Veterinary Medicine, Istanbul University and their anamnesis was gathered. Complete Blood Count (CBC), blood serum biochemistry (Serum glucose, blood urea nitrogen (BUN), creatinine, alanine aminotransferase (ALT), aspartate aminotransferase (AST)) and urine analyses were performed in all patients. Twenty-nine cats were excluded from the study because antimicrobial treatment had already commenced in private veterinary clinics prior to our physical examination. Sixty-one cats with no antimicrobial treatment and including ≥5-6 leucocytes in urine microscopic examination were included in the study. The examination focussed on the presence of pyuria (≥5 white blood cells/high magnification (40x objective; high-power field, (hpf)) which were indicator of LUTI. The cats in the sample group were from different breeds: mixed (n:38), Persian (n:11), Siamese (n:5), Turkish Van (n:3), Turkish Angora (n:4). Forty-one cats were male, 20 cats were female. Five of the cats were one year old or younger, 38 between 2–7 years old and 18 were 8 years old or older. Samples of 5 ml of urine were collected by ultrasound-guided cystocentesis. Cats were restrained in lateral recumbency, the caudal abdomen area was cleaned with alcohol then the needle was inserted. Urine samples for culture and antimicrobial susceptibility tests were sent to the laboratory within 1 hour, stored in cooling boxes.
Medical imaging
Abdominal radiography and ultrasonography were also performed to diagnose underlying urinary diseases/disorders of the cats. Abdominal ultrasonography was performed using a 3.75-MHz convex transducer (Schimadzu 350-A, Shimadzu Corporation, Kyoto, Japan).
Culture
The samples were sent for bacteriological examination to the Laboratory of the Microbiology Department of Istanbul University, Faculty of Veterinary Medicine. Urine samples were inoculated onto nutrient agar supplemented with 7% sheep blood (blood agar) and MacConkey agar plates. While the MacConkey agar plates were incubated aerobically, the blood agar plates were incubated under aerobic and microaerobic conditions at 37°C for 7 days. The colonies were examined macroscopically and then microscopically using Gram staining. Biochemical identification was performed by conventional methods and all the isolates were confirmed with API systems (BioMérieux, SA, Marcy I’Etolie, France) [10,11]. A bacterial count of more than 103 cfu/ml was considered diagnostic of UTI [9]. Cultures with no growth after 7 days were interpreted as negative.
Antimicrobial susceptibility tests
The antibiotic susceptibility tests were performed according to the Kirby-Bauer method recommended by the Clinical Laboratory Standards Institute (CLSI) to select the optimal antimicrobial agent for treatment [12]. The zone of inhibition around the disk (30 μg cefovecin) was measured. The inhibition zone of ≥ 23 mm was considered as susceptible, while 20–22 mm as intermediate and ≤ 19 mm as resistant [6,12].
Statistical analyses
The results were analysed with the SPSS 13.0 programme. The Chi-squared test was used for the comparisons of gender groups and age groups with respect to bacterial growth. Differences were considered significant at p < 0.05.