Eastern Cape Volume 1, Issue 1 April 2009

Wounds in focus


Vision
To be a primary, National, Scientific and Practical Re-source, available to all South African Health Care professionals who share the mission of advancing and serving the field of wound healing and the care of people with wounds.
Mission
To advance the science and the practice of wound healing and the care of people suffering from wounds.

Persistence of the chronic wound Biofiem implicated

Widgerow AD, MBBCh(Wits), FCS(Plast), FACSPrivate Plastic Surgeon, Linksfield Hospital, JohannesburgCorrespondence to: Prof Alan Widgerow, surgeon@iafrica.com

Greeting from Chair-woman!

A very warm welcome to each and eve-ryone reading this newsletter. Woundcare is fast developing into a field of specialty not only for us as nurses, but also for our partners of the multi-disciplinary team we function in, such as doctors, surgeons and podiatrists to mention but a few. With this newsletter, we aim to not only discuss products and woundcare con-cerns but also help find answers and celebrate our successes.

To start I would like to introduce our very own woundcare association, the Wound Healing Association of South Africa (WHASA).

During 1997 the wound care industry in South Africa took the initiative and brought a group of general and plastic surgeons together to form a new interest group. WHASA was born with the aims of promoting the advancement and educa-tion of wound management at all levels of care.

Since then WHASA has joined hands with the Wound Care Chronic wounds by their very nature are recalcitrant and resistant to treat-ment. The pervading illness and pa-thology associated with the particular background disease, be it venous insufficiency, diabetes or the pathol-ogy underlying pressure ulcers have in the past been used as an explana-tion for non-healing and chronicity in these wounds. Thus managing poor perfusions, nutrition, sugar control, avoiding repetitive pressure have been and remain priorities in the overall treatment of these chronic wounds. It is apparent how-ever, that in many cases, even when these processes are managed well, wounds still advance to non-healing and chronicity. Of late more and more authors are looking at biofilm formation and its behaviour charac-teristics as a possible explanation for chronicity in many wounds.

The biofilm concept

Bacteria as we traditionally know them begin as single seeds of a (planktonic) bacterium. They express proteins and structures for motility(flagella) and attachment(fimbria). They aim to seed themselves and disperse to different areas thus exposing widespread areas to their presence and toxicity. In this form they are susceptible to antibiot-ics, some antiseptics and the immune system. In acute wounds they are usu-ally rapidly destroyed or inactivated by neutrophils, antibodies and common wound bed preparations. They are also usually easily identified and cultured.

In the chronic wound however, the bacterium often takes on a different form.Small numbers of these single planktonic bacteria adhere to the sur-face of the wound by attaching to the WHASA Eastern Cape Volume 1, Issue 1 April 2009 Vision To be a primary, National, Scientific and Practical Re-source, available to all South African Health Care professionals who share the mission of advancing and serving the field of wound healing and the care of people with wounds. Mission To advance the science and the practice of wound healing and the care of people suffering from wounds. exposed extracellular matrix; they mul-tiply and develop over time into micro-colonies. These colonies then aggregate into larger groups known as biofilms. The biofilm bacteria are encased in an ex-tracellular polymeric matrix/substance (EPS) which they manufacture them-selves. Within 10 hours, each single-cell planktonic bacterium has differen-tiated into a complex community with defences and resistance to antibiotics. As the colony begins to grow signals are sent out amongst cells - when the cells reach a certain density, known as a quorum, this density is sensed by the cells and they begin to elaborate viru-lence factors which are a potent de-fence against the body’s polymor-phonuclear leukocytes. This process is known as quorum sensing(QS), (Fig 1)

Goals & Objectives

To improve the quality of care to patients through clinical practice, education and research initiatives.

• To provide forums for the exchange of knowledge pertaining to the practice and management of wounds.
• To support professional and/or Accredited wound care programs such as those registered with the South African Nursing Council (SANC) and The South African Qualifica-tions Authority (SAQA)
• To promote increased awareness of the role and contribution of WHASA in wound management
• To establish guidelines relevant to wound healing, wound care and wound management

Greeting from Chair-woman! Cont…. Society of South Africa to form a new united body for all wound care practitio-ners. During 2004, formal structures were created to converge the fragmented local wound care fraternity into a cohe-sive body that would be able to lobby for wound care and its interests in Southern Africa. In December 2004, an Interim Steering Committee was formed to guide the process towards the formation of this formal joint venture. The WHASA Inaugural Wound Care Conference was held 14 - 16 Septem- ber 2005 at Kievits Kroon Country Es-tate, Pretoria, where the proposed Constitution was accepted. The first unified multi-disciplinary Executive Committee was elected under the leadership of Dr. Frans Cronje (More details available on the 'Contact_Us' page on the website). In May 2008 WHASA held its 2nd in-ternational multidisciplinary wound healing conference at the Indaba con-ference centre in Fourways, Johannes-burg. At this conference the new multi-disciplinary EXCO was elected under the leadership of Sr. Liezl Naude with Dr. Gregory Weir as the President-elect. Biofilms continued…... Once the colonies of bacteria form a biofilm, individual bacteria can separate from the biofilm structure through a process called dispersion. Prevalence There is little doubt about the existence of biofilm now. Biopsies of 50 chronic wounds and 16 acute wounds by James showed that 60% of the chronic wound beds demonstrated definite biofilm. Of the 16 acute wounds, only one showed a small patch of biofilm on the wound bed. Current estimates assume that 99.9% of the total microbial biomass on earth exists as a biofilm. It has been estimated by the National Institutes of Health(United States) that more than 80% of persis-tent bacterial infections are likely to involve biofilms. Biofilm models and treatment A major concern in the management of non-healing and infected wounds is the fact that bacteria within a biofilm phenotypically become more tolerant and resistant to antimicrobial therapies when compared with their planktonic counterparts. A few publications have appeared specifically looking at isolating and treating biofilm colonies. A porcine model was used by Davis et al. Using this model, partial-thickness wounds were inoculated with a wound isolate Staphylococcus aureus strain. Wounds were then treated with either one of two topical antimicrobial agents(mupirocin cream or triple antibiotic ointment) within 15 minutes to target planktonic bacteria or 48 hours after initial inoculation to target biofilm-associated wound infection. Using light microscopy, they were able to observe biofilm-like structures in wounds after 48 hours of inoculation and occlusion. Both treatments were effective in reducing planktonic S aureus, but had reduced efficacy against biofilm-embedded S aureus. They demonstrated that S aureus formed firmly attached microcolonies and colonies of bacteria encased in an extracellular matrix on the surface of the wound. These biofilm-like communities also dem-onstrated increased antimicrobial resistance when compared with their planktonic phenotype in vivo.

WHASA offers various membership options

Individual Memebership :

Full Member: R350.00 p/a January – December * Student Member: R150.00 p/a

Benefits:

*Discount to specified journals sup-porting WHASA *Attendance at WHASA events for free if you are a paid-up member *Access to an electronic library via the Internet consisting of various up to date wound care articles *Regular newsletters *Access to other Wound Care En-thusiasts all over the country *Keeping up to date with company workshops around the country and all the WHASA training events

Documents can be downloaded free of charge at : www.whasa.org/B_Membership.asp

As you are able to see, our Associa-tion is a national body working hard at standardizing wound care prac-tices, negotiating with medical aids and uniting wound care practitioners in Southern Africa.

The Eastern Cape also started a branch in September 2007 and it was extended by vote at our seminar in October 2008 to include a wider rep-resentation of the multiprofessional team. The committee members are a dedicated group of motivated profes-sionals who are working hard at bringing knowledge and improved skill to all involved in woundcare.

Each member forms an important link in our chain to bring each of our col-leagues in the field not only knowl-edge, but support, advice and up to date information regarding products and practices.

Should you have queries or concerns please feel free to contact any of them or the chairperson (myself), our secretary Mrs V Smith or the editor of our newsletter, Dr P Huang (see list with contact details as attached).

Please also see our workshop pro-gram as planned for 2009 as we’re wanting to empower each and every-one of our readers with knowledge and skills and as proof of our commit- ment the attendance is free of charge.

Please also book 10,11 September 2009 in your diaries as we’re plan-ning an awesome seminar regarding on chronic wounds in Grahams-town.

Remember that each one of us can make a difference to a patient…no matter how small.

Looking forward hearing from you. God bless until the next issue.

Karin Gerber

Biofilms continued…...

Ideally, agents used in biofilm treatment should be able to dis-rupt its structure. Traditional antibiotics are better at destroying individual bacteria than colonies as seen in biofilm. Many agents are currently being investigated for use against biofilm - these agents mark a shift in traditonal antibiotic mechanistic killing of bacteria. Rather they interfere with the formation of biofilm (xylitol, dispersin B, gallium), the attachment to the matrix (iron scavengers deferoxamins, lactoferrin, ethylene diamine tetraacetic acid [EDTA], degrade EPS (dispersin B, alginase, phage depoly-merases) or inhibit the QS virulence producing mechanism.

Strict adherence to wound management (especially repeated and adequate debridement) should not be underestimated in over-coming biofilm infestation. These principles together with local agents (lactoferrin and xylitol) were successfully used in patients with critical limb ischaemia (CLI). In a report of their results Wolcott and Roads showed an impressive 77% rate of healing in these difficult-to-heal groups of patients. They attributed their excellent results to strict adherence to principles of wound heal-ing (debridement, offloading, perfusion, etc) causing a decrease in matric metalloprteinases (MMPs) and elastase and decreased exudates in the wound environment. Secondly, by targeting biofilm specifically, they felt the effects of their antibiotic and hyperbaric oxygen (HBO) therapies were markedly improved.

The hypothesis

It would appear that more and more investigators are convinced that chronicity of a wound may be related in a large part to the presence of biofilm. The eradication of this virulent phenotype of bacterium is thus becoming an imperative in the treatment of wounds. Multiple authors have looked at biofilm in the context of patients with cystic fibrosis(CF). They point out the obvious similarities with respect to the bacterial infection found in CF and chronic wound patients. They propose that the conditions are kept chronic by the bacterial burden especially that related to P auruginosa, a common pathogen in CF. They propose that the presence of this bacterium in the form of a biofilm and its excretion of damaging virulence factors including an efficient PMN shield, encourages bacterial persistence and may explain the extreme tolerance to antibiotics and the diminished capacity of the immune defence. This view, in relation to chronic wound healing, is one now shared by a large number of wound care researchers.

WHASA COMMITEE MEMBERS CONTACT DETAILS

EASTERN CAPE BRANCH 2009 WORKSHOPS