Abstract:
BACKGROUND : Antimicrobial resistance is becoming increasingly important in both human and veterinary medicine.
This study investigated the proportion of antimicrobial resistant samples and resistance patterns of Staphylococcus
isolates from cats presented at a veterinary teaching hospital in South Africa. Records of 216 samples from cats that
were submitted to the bacteriology laboratory of the University of Pretoria academic veterinary hospital between
2007 and 2012 were evaluated. Isolates were subjected to antimicrobial susceptibility testing against a panel of 15
drugs using the disc diffusion method. Chi square and Fisher’s exact tests were used to assess simple associations
between antimicrobial resistance and age group, sex, breed and specimen type. Additionally, associations between
Staphylococcus infection and age group, breed, sex and specimen type were assessed using logistic regression.
RESULTS : Staphylococcus spp. isolates were identified in 17.6% (38/216) of the samples submitted and 4.6% (10/216)
of these were unspeciated. The majority (61.1%,11/18) of the isolates were from skin samples, followed by otitis
media (34.5%, 10/29). Coagulase Positive Staphylococcus (CoPS) comprised 11.1% (24/216) of the samples of which
7.9% (17/216) were S. intermedius group and 3.2% (7/216) were S. aureus. Among the Coagulase Negative
Staphylococcus (CoNS) (1.9%, 4/216), S. felis and S. simulans each constituted 0.9% (2/216). There was a
significant association between Staphylococcus spp. infection and specimen type with odds of infection
being higher for ear canal and skin compared to urine specimens. There were higher proportions of
samples resistant to clindamycin 34.2% (13/25), ampicillin 32.4% (2/26), lincospectin 31.6% (12/26) and
penicillin-G 29.0% (11/27). Sixty three percent (24/38) of Staphylococcus spp. were resistant to one
antimicrobial agent and 15.8% were multidrug resistant (MDR). MDR was more common among S. aureus 28.6%
(2/7) than S. intermedius group isolates 11.8% (2/17). One S. intermedius group isolate was resistant to all β-lactam
antimicrobial agents tested.
CONCLUSION : S. intermedius group was the most common cause of skin infections and antimicrobial resistance was not
wide spread among cats presented at the veterinary academic hospital in South Africa. However, the presence of MDRStaphylococcus
spp. and isolates resistant to all β-lactams is of both public health and animal health concern.
