Incidence of inducible clindamycin resistance in Staphylococcus pseudintermedius from dogs

Area of Science:

• Veterinary Medicine
• Microbiology
• Antimicrobial Resistance

Background:

• Clindamycin is a common antibiotic for treating canine pyoderma.
• Staphylococcus pseudintermedius is a key pathogen in canine skin infections.
• Antimicrobial resistance is a growing concern in veterinary medicine.

Purpose of the Study:

• To investigate the prevalence of inducible clindamycin resistance in Staphylococcus pseudintermedius isolates from canine pyoderma.
• To evaluate the effectiveness of standard antimicrobial susceptibility testing in detecting this resistance.

Main Methods:

• Isolates of Staphylococcus pseudintermedius were obtained from canine pyoderma cases.
• Double-disk diffusion testing was used to screen for inducible clindamycin resistance.
• Polymerase chain reaction (PCR) was employed to detect the ermB gene, a marker for clindamycin resistance.

Main Results:

• Eight out of 608 Staphylococcus pseudintermedius isolates (1.3%) showed inducible clindamycin resistance.
• These resistant isolates were identified through both phenotypic (double-disk diffusion) and genotypic (PCR for ermB) methods.
• Standard in vitro antimicrobial susceptibility testing may not always detect inducible resistance.

Conclusions:

• Inducible clindamycin resistance exists in Staphylococcus pseudintermedius causing canine pyoderma.
• Veterinarians should consider additional testing for inducible clindamycin resistance in isolates that are erythromycin-resistant but appear clindamycin-susceptible.
• Accurate detection of resistance is crucial for effective treatment of canine pyoderma and preventing further resistance spread.