Evaluation of a silver-impregnated coating to inhibit colonization of orthopaedic implants by biofilm forming methicillin-resistant Staphylococcus pseudintermedius.
OBJECTIVE
To evaluate the in vitro antibacterial activity of a silver-impregnated coating against a biofilm-forming strain of methicillin-resistant Staphylococcus pseudintermedius (MRSP).


METHODS
A clinical MRSP isolate sourced from a failed canine knee implant was evaluated for biofilm production and used in the present study. Using a standard test method and a clinically approved titanium substrate, the antimicrobial activity of a novel silver plasma coating was determined at two times: five minutes after inoculation of the specimens (T0) and after 24 hours of incubation (T24). Scanning electron microscopy was used to evaluate the biofilm formation on specimens.


RESULTS
The tested clinical MRSP isolate was classified as a strong biofilm producer. The silver coating significantly reduced the MRSP growth more than four log steps compared to the non-coated specimens and showed more than 99.98% reduction in the number of colony forming units after 24 hours. Scanning electron microscopy images revealed that silver-coated surfaces did not manifest detectable biofilm, while biofilm formation was readily observed on the control specimens.


CONCLUSIONS
The silver coating exhibited excellent activity against the multidrug resistant biofilm-forming MRSP isolate. The next stage of this work will involve testing in an animal model of orthopaedic infection. Positive results from animal studies would support the introduction of the silver plasma coating as a new strategy for preventing implant contamination, biofilm formation, and surgical infection in dogs undergoing orthopaedic surgery.
Mohammed A
MA
Azab
Matthew J
MJ
Allen
Joshua B. Daniels, DVM, PhD, DACVM, The Ohio State University, College of Veterinary Medicine, 601 Vernon Tharp Dr., Columbus, OH, 43210, United States, Phone: +1 614 247 1725, Fax: +1 614 292 0895, E-mail: daniels.384@osu.edu.
Joshua B
JB
Daniels
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D018441:Biofilms; D004283:Dog Diseases / Q000382:microbiology / Q000517:prevention & control*; D004285:Dogs; D008712:Methicillin / Q000494:pharmacology; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects* / Q000254:growth & development; D019736:Prostheses and Implants / Q000382:microbiology / Q000662:veterinary*; D012834:Silver; D013203:Staphylococcal Infections / Q000662:veterinary*; D014025:Titanium
D000900:Anti-Bacterial Agents; D012834:Silver; D014025:Titanium; D008712:Methicillin
Antibacterial; MRSP; Staphylococcus pseudintermedius; methicillin resistant; preventive; silver