Isolation of a Methicillin-Resistant Staphylococcus pseudintermedius Strain from a Domestic Dog with Vulvovaginitis: A Potential Public Health Concern?
Authors:
- Lorenzo PaceLPLorenzo Pace
- Valeria RondinoneVRValeria Rondinone
- Laura Del SambroLSLaura Del Sambro
- Viviana ManzulliVMViviana Manzulli
- Stefano CastellanaSCStefano Castellana
- Luigina SerrecchiaLSLuigina Serrecchia
- Angelica BiancoABAngelica Bianco
- Beatrice MaffeiBMBeatrice Maffei
- Leonardo MarinoLMLeonardo Marino
- Antonio PetrellaAPAntonio Petrella
- Domenico GalanteDomenico Galante
Open Access
- 9 May 2026
- journal article
- research article
- Published by MDPI AG in Antibiotics
- Vol. 15 (5) , 480
Abstract
Background: Staphylococcus pseudintermedius is a major opportunistic pathogen of dogs and the primary cause of canine pyoderma and other infections. The global emergence of methicillin-resistant S. pseudintermedius (MRSP) represents a significant challenge in veterinary medicine due to its frequent multidrug-resistant phenotype and limited therapeutic options. Methods: We describe the phenotypic and genomic characterization of an MRSP isolate recovered from a vaginal swab of an 11-year-old dog diagnosed with vulvovaginitis in southern Italy. Antimicrobial susceptibility testing was performed using broth microdilution according to CLSI VET01S guidelines. Whole-genome sequencing was conducted to determine sequence type and antimicrobial resistance determinants. Results: The isolate was identified as S. pseudintermedius by MALDI-TOF MS and confirmed by genomic analysis. Multilocus sequence typing assigned the strain to sequence type ST2333. Phenotypically, the isolate exhibited multidrug resistance, including resistance to β-lactams, macrolides, lincosamides, tetracyclines, aminoglycosides, fluoroquinolones, and trimethoprim–sulfamethoxazole, while remaining susceptible to amikacin, rifampicin, florfenicol, and vancomycin. Whole-genome sequencing confirmed the presence of mecA and additional resistance determinants consistent with the observed phenotype. Conclusions: This report suggests the possible occurrence of an MDR MRSP ST2333 lineage in southern Italy and highlights the importance of combined phenotypic and genomic surveillance to support antimicrobial stewardship in veterinary medicine within a One Health framework.Keywords
This publication has 39 references indexed in Scilit:
- Molecular detection and characterization of methicillin-resistant Staphylococcus pseudintermedius (MRSP) ST2361 in a healthcare settingOne Health, 2025
- Methicillin-resistant Staphylococcus pseudintermedius: epidemiological changes, antibiotic resistance, and alternative therapeutic strategiesVeterinary Research Communications, 2024
- Not just in man's best friend: A review of Staphylococcus pseudintermedius host range and human zoonosisResearch in Veterinary Science, 2024
- Diagnostic and commensal Staphylococcus pseudintermedius genomes reveal niche adaptation through parallel selection of defense mechanismsNature Communications, 2023
- Virulent potential of methicillin-resistant and methicillin-susceptible Staphylococcus pseudintermedius in dogsActa Tropica, 2023
- Prevalence and characterization of methicillin-resistant Staphylococcus pseudintermedius from symptomatic companion animals in Northern Italy: Clonal diversity and novel sequence typesComparative Immunology, Microbiology and Infectious Diseases, 2019
- Analysis of mutational patterns in quinolone resistance-determining regions of GyrA and ParC of clinical isolatesInternational Journal of Antimicrobial Agents, 2019
- Frequency, antimicrobial susceptibility and clonal distribution of methicillin-resistant Staphylococcus pseudintermedius in canine clinical samples submitted to a veterinary diagnostic laboratory in Italy: A 3-year retrospective investigationVeterinary Microbiology, 2017
- Human infections due to Staphylococcus pseudintermedius, an emerging zoonosis of canine origin: report of 24 casesDiagnostic Microbiology and Infectious Disease, 2016
- Basic local alignment search toolJournal of Molecular Biology, 1990