Clinical Update Innovations in infection control


molecular methods to guide the use of personalised gels improved healing further at six months [16]


encoded FLX amplicon pyrosequencing (bTEFAP). PLoS One 2008; 3(10): e3326. . The gels contain


high quantities of antibiotics and anti-biofilm agents that specifically target any bacteria present. It may be that, by comprehensively suppressing wound biofilm, chronic wounds will heal more effectively.


Conclusion With the emergence of clinically meaningful diagnostic tests, such as PCR and sequencing, wound care can move away from trial and error to the more standard medical model of diagnosis followed by treatment. However, today’s molecular methods are in the pioneering phase and still face barriers in terms of being widely accepted. This is due, in part, to the high cost of the tests and the need for highly trained personnel, but is mainly because these methods yield a high-quantity data, which is currently unfamiliar. However, new technologies are rapidly emerging, which


will provide more accurate, faster, cheaper and far more comprehensive identification of all microbes in chronic wounds. Molecular methods are certain, therefore, to become the preferred way of identifying microbial presence in chronic wounds.


Randall Wolcott is medical director of Southwest Regional Wound Care Center, Texas, US.


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11. James GA, Swogger E, Wolcott R, Pulcini E, Secor P, Sestrich J, Costerton JW, Stewart PS. Biofilms in chronic wounds.Wound Repair Regen. 2008; 16(1): 37–44.


12. Rhoads DD, Wolcott RD, Dowd SE. Comparison of Culture and Molecular Identification of Bacteria in Chronic Wounds. Int J Mol Sci 2012; 13: 2535–50.


13. Dowd SE, Wolcott RD, Sun Y, McKeehan T, Smith E, Rhoads D. Polymicrobial nature of chronic diabetic foot ulcer biofilm infections determined using bacterial tag


Figure 1. This image shows a critically colonised pressure ulcer. Although the wound lacks the typical inflammatory signs and symptoms, wound healing did not progress despite optimal treatment. After the application of antiseptics, the wound started to heal.


www.woundsinternational.com 13


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15. Wolcott RD, Cox SB, Dowd SE. Healing and healing rates of chronic wounds in the age of molecular pathogen diagnostics J Wound Care 2010; 19(7): 272–8, 280–81.


16. Dowd SE, Wolcott RD, Kennedy J, Jones C, Cox SB. Molecular diagnostics and personalised medicine in wound care: assessment of outcomes. J Wound Care 2011; 20(5): 232, 234, 239.


Innovations in wound infection management


I


nfection in chronic wounds still remains a major problem in wound management since it sometimes leads to lethal complications, such as osteomyelitis,


cellulitis, bacteraemia and sepsis. Once wound infection occurs, it can easily develop into these conditions, thus early detection and diagnosis is essential. The difficulty in diagnosing wound infection is often due to the absence of the typical inflammatory symptoms, including pain, redness, swelling, and heat, which indicate critical colonisation [Fig 1]. Since critically colonised wounds cannot be defined by clinical signs, clinicians sometimes fail to treat the wound in its early stage of infection. The authors proposed a new way of identifying these conditions by focusing on gene expression of bacteria and host. The aim is to introduce their strategy and discuss future issues regarding wound infection control. The relationship between bacterial virulence and host immune response is generally conceptualised as a state of balance. If the bacterial virulence surpasses the host immunity, the wound will not heal and will lead to infection or critical colonisation. In contrast, if the host immunity overwhelms the bacterial virulence, the wound will heal without any excessive inflammatory signs, described as colonisation or contamination. Diagnosing infected or critically colonised wound is usually based on bacterial count and clinical features.


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