Fabric with silver thread role in the control of bacterial contamination in critically ill patients

Silver has an intriguing, long history used for its antibiotic properties in human health care. It has been used in water purification, wound care, bone prostheses, reconstructive orthopaedic surgery, cardiac devices, catheters and surgical appliances, dressings and textiles. Advancing biotechnology has enabled incorporation of ionizable silver into fabrics, textiles and dressings for clinical use to reduce the risk of nosocomial infections and for personal hygiene. The antimicrobial action of silver is proportional to the bioactive silver ion (Ag(+)) released and its availability to interact with bacterial or fungal cell membranes. Silver metal and inorganic silver compounds ionize in the presence of water, body fluids or tissue exudates. The silver ion is biologically active and interacts with proteins, amino acid residues, free anions and receptors on mammalian and eukaryotic cell membranes. Bacterial sensitivity to silver is genetically determined and relates to the levels of intracellular silver uptake and its ability to interact and irreversibly denature key enzyme systems. Silver exhibits low toxicity in the human body. Minimal risk is expected due to clinical exposure by inhalation, ingestion, dermal application or through the urological or haematogenous route. Chronic ingestion or inhalation of silver preparations (especially colloidal silver) can lead to deposition of silver metal/silver sulphide particles in the skin (argyria), eye (argyrosis) and other organs. These are not life-threatening conditions but cosmetically undesirable. Silver is absorbed into the human body and enters the systemic circulation as a protein complex to be eliminated by the liver and kidneys. This complex mitigates the cellular toxicity of silver and contributes to tissue repair. Silver allergy is a known contraindication for using silver in medical devices or antibiotic textiles.