Bacterial Burden of Worn Therapeutic Silver Textiles for Neurodermitis Patients and Evaluation of Efficacy of Washing

Abstract

To reduce pruritus and colonization with Staphylococcus aureus, textiles containing silver are increasingly used as therapeutic option for patients with atopic dermatitis (AD). While wearing such textiles, the contained silver is in close contact with the patient’s skin. The silver serves two purposes: to reduce bacterial colonization of the skin, and to prevent contamination of the textile with ensuing growth of microorganisms. It is unknown whether the silver impregnation is able to reduce bacterial contamination of the textile during wearing and to prevent bacterial growth within the textile. The aim of this study was to investigate the bacterial contamination in textiles containing silver versus placebo worn by patients with AD and to determine the efficacy of processing worn textiles by manual and machine-based washing. Additionally, the effect of silver textiles on S. aureus and total bacterial counts colonizing the skin of AD patients was analyzed. The reduction factor of silver textile compared to placebo was 0.5 log steps against S. aureus and 0.4 log steps against total bacteria. Silver textiles exhibited significantly less S. aureus as well as total bacterial colonization after 2 days of wearing without washing, as compared with a placebo textile. On placebo textiles 385.6 ± 63.5 CFU total bacteria and 236.5 ± 49.9 CFU S. aureus, and on silver textiles 279.9 ± 78.7 CFU total bacteria and 119.3 ± 39.4 CFU S. aureus were found on the inner side of the textiles facing the neurodermitis lesions. However, the unexpectedly high residual contamination despite the silver exposure represents a potential risk as recontamination source of S. aureus that could maintain the proinflammatory process in AD. This contamination is nearly completely eliminated by machine-based washing at 60°C using conventional washing powder. AD patients wearing silver textiles should change their used clothes at least daily and wash them in a washing machine at 60°C.

Evaluation of antimicrobial textiles for atopic dermatitis

“…Silver textiles act by releasing silver ions onto the patient's skin . For reasons of hygiene, household machine washing is crucial to keep the clothing clean of bacteria . Therefore, clinically useful silver textiles must be resistant to household washing.…”

“…On the other hand, a previous study showed that the amount of bacteria present on the unwashed silver-containing fabric 'Juzo Skin Protect Silver' was lower than on placebo fabrics. 11 This might correspond to a possible destruction of the silver coating due to aggressive knitting, depend on the technology and machinery used, or result from the suboptimal release of Ag + antibiotic ions from certain types of fibres. Latest customized and milder knitting techniques might lead to the production of more stable functional textiles.…”

Pilot study on the microbial contamination of conventional vs. silver-impregnated uniforms worn by ambulance personnel during one week of emergency medical service

“…After 2 days of wearing the placebo textile, the inside yielded 385.6±63.5 CFU and 236.5±49.9 CFU S. aureus , and 279.9±78.7 CFU and 119.3±39.4 CFU S. aureus were detectable on the silver textile. By daily washing at 60°C with conventional laundry detergent, contamination in both cases was almost completely eliminated [1]. …”

“…The incorporation of antimicrobials into everyday products, such as the coating or impregnation of surfaces in refrigerators and food-storage containers to prevent mold infestation or bacterial decay, the antibacterial impregnation of sport socks to avoid odor, or weaving silver threads into textiles as a supportive treatment of atopic dermatitis [1], is increasing. Similarly, antimicrobial impregnation of surfaces, textiles, and clothing in the hospital is increasingly advertised as being able to prevent infection through their antibacterial properties.…”

Leitlinie Neurodermitis [atopisches Ekzem; atopische Dermatitis]

“…Daeschlein et al fokussierten auf die Fragestellungen, inwieweit es durch das Tragen von Silbertextilien bei Patienten mit Neurodermitis zu einer bakteriellen Kontamination kommt und auf die Wirksamkeit verschiedener Waschverfahren (maschinell vs. Handwäsche) . Die Ergebnisse zeigen, dass Silbertextilien im Vergleich zu Kontrolltextilien ohne Silber nach zwei Tagen ohne Waschung zwar weniger S. aureus aufwiesen, die Kontamination aber dennoch unerwartet hoch war, so dass hier von einem Rekontaminationsrisiko ausgegangen werden muss.…”