Related Experiment Video
Updated: Apr 27, 2026
Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus MRSA
Published on: February 9, 2011
Antimicrobial susceptibility of methicillin-resistant Staphylococcus pseudintermedius isolated from veterinary
Abstract:
Staphylococcus pseudintermedius is a leading aetiologic agent of pyoderma and other body tissue infections in dogs and cats. In recent years, an increased prevalence of methicillin-resistant S. pseudintermedius (MRSP) has been reported. Isolation of MRSP in serious infections poses a major therapeutic challenge as strains are often resistant to all forms of systemic antibiotic used to treat S. pseudintermedius -related infections. This study investigates the occurrence of MRSP from a total of 7183 clinical samples submitted to the authors' laboratories over a 15-month period. Identification was based on standard microbiological identification methods, and by S. pseudintermedius-specific nuc polymerase chain reaction (PCR). Methicillin resistance was confirmed by PBP2a latex agglutination and mecA PCR. Susceptibility against non-beta-lactam antibiotics was carried out using a disc-diffusion method according to Clinical and Laboratory Standards Institute (CLSI) guidelines. In addition, susceptibility to pradofloxacin--a new veterinary fluoroquinolone--was also investigated. SCCmec types were determined by multiplex PCR. Staphylococcus pseudintermedius was isolated from 391 (5%) samples and 20 were confirmed as MRSP from cases of pyoderma, otitis, wound infections, urinary tract infection and mastitis in dogs only. All 20 isolates were resistant to clindamycin and sulphamethoxazole/trimethoprim. Nineteen were resistant to chloramphenicol, enrofloxacin, gentamicin, marbofloxacin and pradofloxacin; additionally, seven isolates were resistant to tetracycline. Fifteen isolates carried SCCmec type II-III, four isolates had type V and one harboured type IV. To date, only a few scientific papers on clinical MRSP strains isolated from the UK have been published, thus the results from this study would provide additional baseline data for further investigations.
Insights
Methicillin-resistant Staphylococcus pseudintermedius (MRSP) is a growing concern in canine infections. This study found 20 MRSP isolates from 7183 clinical samples, highlighting significant antibiotic resistance and the need for further UK-based research.
Area of Science:
- Veterinary Microbiology
- Antimicrobial Resistance
- Canine Infectious Diseases
Background:
- Staphylococcus pseudintermedius is a common cause of pyoderma and other infections in dogs and cats.
- The emergence of methicillin-resistant S. pseudintermedius (MRSP) presents a significant therapeutic challenge due to widespread antibiotic resistance.
Purpose of the Study:
- To investigate the prevalence and antimicrobial susceptibility of MRSP in clinical samples from dogs and cats.
- To characterize the SCCmec types of identified MRSP isolates.
- To provide baseline data on MRSP in the UK.
Main Methods:
- Analysis of 7183 clinical samples over 15 months.
- Identification of S. pseudintermedius using standard methods and nuc PCR.
- Confirmation of methicillin resistance via PBP2a latex agglutination and mecA PCR.
- Antimicrobial susceptibility testing using disc-diffusion (CLSI guidelines) and investigation of pradofloxacin resistance.
- SCCmec typing using multiplex PCR.
Main Results:
- Staphylococcus pseudintermedius was isolated from 391 (5%) samples.
- Twenty MRSP isolates were confirmed, exclusively from canine infections (pyoderma, otitis, wound, UTI, mastitis).
- All MRSP isolates were resistant to clindamycin and sulphamethoxazole/trimethoprim.
- High resistance rates were observed for chloramphenicol, enrofloxacin, gentamicin, marbofloxacin, and pradofloxacin (19/20 isolates).
- Seven isolates showed tetracycline resistance.
- SCCmec types II-III (15 isolates), V (4 isolates), and IV (1 isolate) were identified.
Conclusions:
- MRSP is present in canine clinical infections in the UK, exhibiting resistance to multiple antibiotics, including newer agents like pradofloxacin.
- The prevalence of specific SCCmec types suggests potential transmission routes and warrants further epidemiological investigation.
- This study provides crucial baseline data for understanding MRSP epidemiology and guiding therapeutic strategies in veterinary medicine.
Related Concept Videos
01:25Clinical Significance of Antibiotic Resistance
01:25Mechanism of Antibiotic Resistance in MRSA
01:24Automated Microbial Diagnostics
01:29Staphylococcal Skin Infections
01:28Antimicrobial Effectiveness