EUROPEAN  TISSUE  REPAIR  SOCIETY

WOUND HEALING IN AFRICA (TANZANIA)
Terence J Ryan
Department of Dermatology, Churchill Hospital, Oxford

As in previous articles about wound healing in the developing world it is useful to consider causes of delay in healing as local, general and organisational. (Table 1, Ryan 1997). Africa and Tanzania in particular have special problems but, nevertheless, the majority of the wounds like those in the developed world are due to traffic accidents, fire-arms and household domestic fires, wounds from being hit with a machete or animal bites or traps are exotic and hence rare. These countries need a regime of accident prevention of a kind which has reduced road accidents and burns in the developed world. An enforced highway code, safer household fires and the use of non-flammable materials for furniture or party dresses have still to reach these countries.

Infection plays a greater role as a cause of non healing. Some of the infections are tropical such as the rising prevalence of mycobacterium ulcerans (the Buruli ulcer) or tuberculosis, syphilis and yaws, but these are still relatively rare. One of the commonest ulcers is the so-called tropical ulcer, particularly common in young men and which has been blamed on mixed flora including anaerobic organisms. A feature of many of these wounds is that they are relatively speaking non-inflammatory in appearance. Since editing the recent symposium on warming in wound healing (Ryan et al, 2000) I have become more aware of the cold wound. It is an indication of a poor blood supply, but also of a low metabolism, failing to support wound healing which may be stimulated by warming. Although these countries are tropical, some wounds are relatively cold and while the days may be hot, the nights are cold also. Some of the environments from which the bacteria are derived are cool, muddy waters with a low temperature optimal for the growth of organisms and much lower than the human body temperature but not of cold wounds!

A feature of many chronic wounds is that they are anaerobic, but then it must be realised that the skin is relatively anaerobic. When it is healthy its relatively rich blood supply is there to provide thermoregulation and more especially the moisturisation of a resilient elastic organ (Ryan 1990). The epidermis of a healthy skin is mostly like the red cell functioning without a living nucleus and mitochondria and all the cytokines that it produces are not easily demonstrated at rest or in health. The response of the epidermis to tissue repair is an astonishing increase in activity including mitosis, migration and the production of cytokines, growth factors and eiconasoids. All of this requires an aerobic metabolism not characteristic of the healthy skin at rest. The dominant characteristic. of the skin in repair is thus its ability to stimulate a blood supply sufficient to meet the needs of an aerobic metabolism notwithstanding meeting the needs of all the other cells like the neutrophil and macrophage which are brought into aid the initial wound healing process. The characteristic of all these cells is that they come from a warm environment, well supplied with oxygen and they migrate into a cooler anaerobic wound. In most rapidly repairing wounds anaerobic status is rapidly developed. This is not so in the chronic anaerobic tropical non healing wound into which much more research is needed.

AIDS in Africa has been officially declared a disaster in some countries. It is well known that the wounds of the immuno-compromised patient heal less well and this may not be entirely due to their susceptibility to chronic infection but may have something to do with impaired cytokine production and their failure to stimulate wound healing. This too, needs further study.

I have said elsewhere that the main reason for non-healing wounds in most countries is health service organisation failure. In the developed world it is only the elite wound healing unit that can produce the best healing rates. Most people with wounds that are failing to heal, are out there in a relatively impoverished community, impoverished both in terms of finance but also in the poverty of knowledge and best practice. In Africa, as in many other developing countries, there is a special problem and that is that there is a second health service in the traditional medicine paradigm. It is estimated that 80% of persons in the developing world first of all attend a traditional healer. The export of conventional western medicine to these countries carries with it a view that all traditional medicine is unscientific and witchcraft. In fact traditional medicine is traditional knowledge, which for the local community can carry with it extraordinary insights. So far as wound healing is concerned the use of plant and other biological materials provides many rich constituents that are antiviral, antibacterial and antioxidant and sometimes full of growth factors.

One of the greatest needs is to provide integration of traditional medicine with conventional medicine to provide a locally sustainable and low cost therapy of wounds which is safe and effective. This could be done if the two systems of medicine would speak to each other and develop trust.

It is the policy of the Regional Dermatology Training Centre in Tanzania to do all of this and hence to provide a basis of research into locally available low cost medicines. By setting up a friendly relationship with Traditional Healers in which they receive instruction and in return provide information one can at the same time meet a need to promote a free flow of patients. This must be a two way flow, both systems must benefit. In Tanzania we find that there are many patients whom we are unable to help, such as those dying from AIDS. Sending them back to their communities they derive much support from the Traditional Healer. Even when patients arrive in hospital they may still benefit from taking into account their beliefs as to the causation of their illnesses and traditional knowledge may help to achieve this.

Currently our plan in Tanzania is to research wound healing agents such as honey, especially locally derived brands, certain herbal remedies and to set up larval therapy for the debridement of the more necrotic wounds. We are finding it necessary to seek finance for purpose built buildings for those with AIDS. However hard one tries, for example in intensive care, such units are not available to all. The fact that 61% of our admissions are HIV positive and there are risks to those that are not positive makes it difficult to control discrimination. As indicated above (and in the table), when the wound does not heal the African has more reasons than most for remedying the wide range of defects that are locally in the wound, generally in the body and organisational in the environment

References

Ryan TJ (1997), Global curriculum for wound management in Tropical Doctor, eds. Gerard Bodeker and Eldryd Parry, Royal Society of Medicine 27, Supplement No. 1, Volume 27, 31–35.

Ryan TJ, Healthy Skin for All (1997), the International Foundation for Dermatology (obtainable from the Office of Wound Healing, Department of Dermatology, Churchill Hospital, Oxford).

Ryan TJ (1995), Exchange and the mechanical properties of the skin: Oncotic and hydrostatic forces control by blood supply and lymphatic drainage. Wound Repair and Regeneration Vol. 3, No. 3, 258–264.

Ryan TJ, Cherry GW, Harding KG (2000), Warming and Wound healing: Warm-up^® active wound therapy. Royal Society of Medicine International Congress and Symposium Series, 257, 1–92.

For further information contact:

Prof Terence Ryan
Department of Dermatology
Churchill Hospital, Old Road
Headington, Oxford, OX3 7LJ
Tel: 01865 228258