Staphylococcus aureus Causing Skin and Soft Tissue Infections in Companion Animals: Antimicrobial Resistance Profiles and Clonal Lineages

Abstract

Staphylococcus aureus is a relevant agent of skin and soft tissue infections (SSTIs) in animals. Fifty-five S. aureus comprising all SSTI-related isolates in companion animals, collected between 1999 and 2018 (Lab 1) or 2017 and 2018 (Lab 2), were characterized regarding susceptibility to antibiotics and heavy metals and carriage of antimicrobial resistance determinants. Clonal lineages were established by PFGE, MLST and agr typing. Over half of the isolates (56.4%, 31/55) were methicillin-resistant S. aureus (MRSA), and 14.5% showed a multidrug resistance (MDR) phenotype. Resistance was most frequently observed for beta-lactams (81.8%, related to blaZ and/or mecA), fluoroquinolones (56.4%) and macrolides/lincosamides (14.5%, related to erm(A) or erm(C)). The distributions of heavy-metal MICs allowed the detection of non-wild-type populations associated with several resistance genes. The collection showed genetic diversity, with prevalence of clonal lineage ST22-agrI (45.5%, 25/55), comprising only MRSA isolates, and several less frequently detected clones, including ST5-agrII (14.6%, 8/55), ST398-agrI (9.1%, 5/55) and ST72-agrI (7.3%, 4/55). This work highlights the high frequency of SSTI-related MRSA strains that reflect the clonal lineages circulating both in companion animals and humans in Portugal, reinforcing the need for a One Health approach when studying staphylococci causing infections in companion animals.

Fluorescent Light Energy in the Management of Multi Drug Resistant Canine Pyoderma: A Prospective Exploratory Study

“…Canine pyoderma is a family of cutaneous disorders frequently diagnosed in small animal practice [ 1 , 2 ], conventionally treated with both topical and systemic antibiotics [ 3 , 4 ]. Managing canine pyoderma is becoming more difficult due to the presence of multidrug-resistant (MDR) staphylococci which are progressively encountered by veterinary practitioners, especially in dermatologic area [ 5 , 6 ] In the past few years, veterinary staff are facing the burden of increased antimicrobial resistance [ 5 ] Multi Resistant Staphylococcus Pseudintermedius (MRSP) has been diagnosed mainly in pyoderma and otitis in dogs, cats, and horses whose prevalence varies according to the geographical location [ 7 , 8 ] It has been estimated a MRSP prevalence varying from 15.6 to 17% in USA up to 67% in dogs presenting pyoderma in Japan [ 9 , 10 , 11 ] In dogs, MRSP infection has been found to have an estimated prevalence of 7% [ 12 ] which is expected to raise, augmenting the risk of MDR transmission in domestic environment [ 13 ] Multidrug resistance initiated and incited a remarkable change in philosophy of systemic therapy and especially oral antibiotic treatment [ 14 , 15 ] MDR has also enhanced the necessity for new medications intended for local use and with antibiotic-sparing effect for MDR strains [ 16 ] Local care for bacterial skin diseases has been an innovation of veterinary dermatology since its establishment, but for a long time, it has been supposed to be only an add-on to oral antibiotics, regarded as key therapy [ 17 ].…”

Virulence Potential of Biofilm-Producing Staphylococcus pseudintermedius, Staphylococcus aureus and Staphylococcus coagulans Causing Skin Infections in Companion Animals

“…The most common S. pseudintermedius and S. aureus lineages include a high frequency of biofilm-producing strains. Nearly half of the S. aureus collection studied, gathered over a 19 year period, comprised ST22- agrI -MRSA isolates [ 45 ], 88.0% of which were biofilm producers. The second and third S. aureus predominant lineages, ST5- agrII -MRSA/MSSA (12.7%) and ST398- agrI -MRSA/MSSA (9.1%), respectively, only included biofilm producers.…”

“…However, only one S. aureus presented the lukF-PV / lukS-PV genes. This strain was collected from a rabbit and was the only representative of the clonal lineage ST121- agrIV in the study collection [ 45 ].…”

“…Both clinical strains are MRSA and strong biofilm producers and belong to clonal lineages that are prevalent in our study collection. Strain BIOS-V151 belongs to ST398- agrI [ 45 ], a lineage frequently associated with food-producing or companion animals [ 19 ]. On the other hand, BIOS-V204 belongs to ST22- agrI , the predominant lineage in our pyoderma-related S. aureus collection as well as in S. aureus from skin infections in humans in the community [ 83 ], highlighting concerns on the sharing of such strains between animals and humans.…”

“…A few strains were isolated from the same animal host, as follows: 12 S. pseudintermedius strains were isolated from six dogs (two strains/dog) and six other S. pseudintermedius strains were isolated from two dogs (three strains/dog); eight S. aureus strains were isolated from two dogs, one cat and one rabbit (two strains/animal); two S. coagulans were isolated from the same dog. All strains have been previously characterized regarding their antimicrobial susceptibility profiles, and their clonal lineages were determined by PFGE and/or MLST [ 45 , 46 , 47 ]. The main strain characteristics are summarized in Supplementary Material S2 .…”