Antibacterial properties of a silver chloride-coated nylon wound dressing.
OBJECTIVE
A silver chloride-coated nylon wound dressing (Ag-WD) was evaluated in vitro for antimicrobial activity against five common equine wound pathogens.


METHODS
Bacterial susceptibility study.


METHODS
Equine wound pathogens: Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Streptococcus equi subspecies zooepidemicus, and Staphylococcus aureus.


METHODS
An inoculum of each pathogen was incubated directly with Ag-WD and quantitated after 24 to 48 hours of incubation. To determine if bactericidal activity of Ag-WD was contact dependent, an inoculum of E. coli and Staphylococcus aureus was incubated separately from Ag-WD by a filter and quantitated after 18 hours of incubation. Inductively coupled plasma emission spectrometry (ICP) determined the silver concentration of Mueller-Hinton broth containing Ag-WD after 24 hours of incubation. To establish if the rate of bacterial killing by Ag-WD differed from a constant silver concentration, pathogens were exposed to a silver concentration of 6.45 microg/mL and quantitated after 18 hours.


RESULTS
Direct exposure to Ag-WD significantly reduced bacterial numbers after 15 minutes for K. pneumoniae, 30 minutes for E. coli, 1 hour for P. aeruginosa, and 2 hours for S. equi subspecies zooepidemicus and Staphylococcus aureus. Indirect exposure to Ag-WD resulted in > or =99.9% and > or =90% kill of the inoculum doses of E. coli at 2 hours and Staphylococcus aureus at 18 hours, respectively. Incubation of the pathogens at the constant silver concentration resulted in bacterial killing rates similar to those obtained by incubation with Ag-WD.


CONCLUSIONS
In vitro, equine pathogens are effectively killed when exposed to Ag-WD, and the rate of bacterial killing by Ag-WD is similar to a constant silver concentration of 6.45 microg/mL.


CONCLUSIONS
The in vitro antimicrobial properties of this silver-coated nylon wound dressing are promising for future prevention of equine wound infections.
Adams
A P
AP
Department of Clinical and Population Sciences, University of Minnesota, College of Veterinary Medicine, St. Paul, USA.
Santschi
E M
EM
Mellencamp
M A
MA
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects*; D001458:Bandages / Q000662:veterinary*; D006736:Horses / Q000293:injuries* / Q000601:surgery*; D008826:Microbial Sensitivity Tests / Q000662:veterinary; D009757:Nylons; D018030:Silver Compounds / Q000494:pharmacology*; D013530:Surgical Wound Infection / Q000517:prevention & control / Q000662:veterinary*; D014945:Wound Healing
D000900:Anti-Bacterial Agents; D009757:Nylons; D018030:Silver Compounds; C037548:silver chloride