Biofilm-forming ability and antimicrobial resistance in Staphylococcus intermedius isolated from dog-to-dog bite wounds.

Oliveira M, Mouro S, Niza M, Lobo Vilela C., Biofilm-forming ability and antimicrobial resistance in Staphylococcus intermedius isolated from dog-to-dog bite wounds, Online J Vet Res., 13 (2):56-63, 2009. Staphylococci are commonly found in infected wounds, although their virulence may differ among the strains. One of the relevant virulence factors identified in staphylococci is the biofilm-forming ability, which allows for the evasion of host defences and survival at high antimicrobial concentrations. Biofilm formation by Staphylococcus intermedius isolates from infected and non-infected dog-to-dog bite wounds was evaluated using a Fluorescent In Situ Hybridisation (FISH) protocol. Seven isolates (43.75%) were able to form biofilm in vitro. Although no association was found between wound infection and biofilm formation by S. intermedius (Friedman’s Test), biofilm production may influence the outcome of an infection, by impairing antibiotherapy efficacy. In our study, biofilm production was related to resistance to antimicrobial compounds from most classes (Friedman’s Test), with exception for the β-lactams AMP, P and PRL and the lincosamide DA. Further studies are also required to determine whether biofilm-producing ability of S. intermedius is a significant virulence trait for skin infections in dogs, and its potential zoonotic role.