Abstract
Staphylococcus pseudintermedius is a commensal bacterium frequently isolated from canine skin and recognized as a zoonotic agent especially for dog-owners. This study focused on (a) the antibiotic-resistance phenotypes; (b) the ability to produce biofilm (slime); and (c) the dissemination of virulence factors in S. pseudintermedius strains. Seventy-three S. pseudintermedius strains were screened for antibiotic-resistance against 22 different molecules by means of Kirby-Bauer assay. The ability to produce biofilm was investigated using the microtiter plate assay (MtP) and the amplification of icaA and icaD genes. Virulence factors such as cytotoxins (lukI), enterotoxins (seC), and exfoliative toxins (siet, expA, and expB) were evaluated. The antibiotic-resistance profiles revealed 42/73 (57%) multi-drug resistant (MDR) strains and 31/73 (43%) not-MDR. All the MDR strains and 8/31 (27%) of not-MDR resulted in biofilm producers. Leukotoxin LukI was found in 70/73 (96%) of the isolates. Moreover, the enterotoxin gene seC was detected in 47/73 (64%) of the strains. All the isolates carried the siet gene, whereas expA and expB were found in 3/73 (4%) and 5/73 (7%), respectively. In conclusion, S. pseudintermedius should be considered a potential zoonotic and human agent able to carry different virulence determinants and capable of producing biofilm which facilitates horizontal gene transfer.
Highlights
Staphylococcus pseudintermedius (SP) is one of the youngest members of the Staphylococcus genus, being described and recognized only in 2005 [1], with the first reported case in humans in 2006 [2] and the first molecular identification protocol in 2009 [3]
Even if infections in humans are less common than those reported in pets, the description of S. pseudintermedius as a human pathogen is being increasingly reported [7–9], little is known about its pathogenesis and distribution, and in human medicine is still misdiagnosed as S. aureus [10]
A progressive expansion in resistance to commonly prescribed antimicrobial agents has been observed in the past years, in particular with the emergence and the global spread of multi drug resistant (MDR) bacteria with particular regards for the Methicillin Resistant S. pseudintermedius (MRSP) clones that dramatically complicate the treatment of these infections [7,11]
Summary
Staphylococcus pseudintermedius (SP) is one of the youngest members of the Staphylococcus genus, being described and recognized only in 2005 [1], with the first reported case in humans in 2006 [2] and the first molecular identification protocol in 2009 [3]. It is an opportunistic pathogen known as one of the leading cause of skin, ear, and post-surgical infections in domestic animals, especially in dogs [4–6]. The ability to form biofilm is one of the major virulence determinants studied nowadays in bacteria because it facilitates the adherence to biotic and/or abiotic surfaces [12]. Ica-independent biofilm formation has been reported in staphylococci [16–18]
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have