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Genomic Features of Antimicrobial Resistance in Staphylococcus pseudintermedius Isolated from Dogs with Pyoderma in
Mariela E Srednik1,2, Claudia A Perea1,2, Gabriela I Giacoboni3
1Postdoctoral Research Participation Program, Office of Research in Science and Education, Oak Ridge Associated Universities, Oak Ridge, TN 37831, USA.
Abstract:
Staphylococcus pseudintermedius is the most common opportunistic pathogen in dogs and methicillin resistance (MRSP) has been identified as an emerging problem in canine pyoderma. Here, we evaluated the antimicrobial resistance (AMR) features and phylogeny of S. pseudintermedius isolated from canine pyoderma cases in Argentina (n = 29) and the United States (n = 29). 62% of isolates showed multi-drug resistance. The AMR genes found: mecA, blaZ, ermB, dfrG, catA, tetM, aac(6')-aph(2″), in addition to tetK and lnuA (only found in U.S. isolates). Two point mutations were detected: grlA(S80I)-gyrA(S84L), and grlA(D84N)-gyrA(S84L) in one U.S. isolate. A mutation in rpoB (H481N) was found in two isolates from Argentina. SCCmec type III, SCCmec type V, ΨSCCmec57395 were identified in the Argentinian isolates; and SCCmec type III, SCCmec type IVg, SCCmec type V, and SCCmec type VII variant in the U.S. cohort. Sequence type (ST) ST71 belonging to a dominant clone was found in isolates from both countries, and ST45 only in Argentinian isolates. This is the first study to comparatively analyze the population structure of canine pyoderma-associated S. pseudintermedius isolates in Argentina and in the U.S. It is important to maintain surveillance on S. pseudintermedius populations to monitor AMR and gain further understanding of its evolution and dissemination.
Insights
Methicillin-resistant Staphylococcus pseudintermedius (MRSP) is a growing concern in canine pyoderma. This study analyzed antimicrobial resistance and genetic diversity of MRSP in dogs from Argentina and the U.S., revealing multi-drug resistance and distinct genetic profiles.
Area of Science:
- Veterinary Microbiology
- Antimicrobial Resistance
- Canine Infectious Diseases
Background:
- Staphylococcus pseudintermedius is a common cause of bacterial skin infections in dogs.
- Methicillin-resistant Staphylococcus pseudintermedius (MRSP) is an emerging threat in canine pyoderma.
- Understanding MRSP's genetic makeup and resistance patterns is crucial for effective treatment.
Purpose of the Study:
- To compare the antimicrobial resistance (AMR) features and phylogenetic relationships of Staphylococcus pseudintermedius isolates from canine pyoderma cases in Argentina and the United States.
- To identify specific AMR genes, mutations, and mobile genetic elements contributing to resistance.
- To analyze the population structure and clonal dissemination of S. pseudintermedius between the two countries.
Main Methods:
- Isolation and characterization of S. pseudintermedius from canine pyoderma cases in Argentina (n=29) and the U.S. (n=29).
- Antimicrobial susceptibility testing and detection of key AMR genes (e.g., mecA, blaZ, ermB, tetM).
- Whole-genome sequencing or targeted sequencing for phylogenetic analysis, including SCCmec typing and sequence type (ST) determination.
Main Results:
- 62% of isolates exhibited multi-drug resistance.
- Common AMR genes included mecA, blaZ, ermB, dfrG, catA, tetM, and aac(6')-aph(2″).
- Distinct SCCmec types and sequence types were identified, with ST71 identified in both countries, suggesting clonal spread.
Conclusions:
- Significant antimicrobial resistance and multi-drug resistance are prevalent in canine pyoderma-associated S. pseudintermedius from Argentina and the U.S.
- Comparative analysis reveals variations in AMR gene profiles and SCCmec types between the two regions.
- Ongoing surveillance is essential to monitor the evolution and dissemination of resistant S. pseudintermedius strains in the canine population.
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