Cath Lab Digest

A 2-cm x 1-cm full-thickness cutaneous biopsy was taken from the inner part of the upper arm of the patient and sent to the laboratory for the extraction and further separate cultivation of the fibroblasts and keratinocytes. The isolated autologous fibroblasts were grown on a three-dimensional nonwoven fleece of hyaluronic acid; whereas, the autologous keratinocytes were grown on a thin, laser-drilled microperforated transparent membrane of hyaluronic acid.⁹

After thorough cleansing of the ulcer, the tissue-engineered autologous dermal-like substitute was placed in direct contact with the wound bed (see Figure 2). After two applications (7 days apart), the tissue-engineered autologous epidermal-like substitute was placed on the wound (see Figure 3). A paraffin gauze and a gauze soaked with saline solution were used as secondary dressings.

During treatment, the patient was seen twice a week at the clinic to change the secondary dressings and assess the wound (see Figure 4). A transparent acetate grid was used to measure the dimensions of the wound. The depth of the wound also was measured.

A fiberglass splint was required to immobilize the ankle throughout the treatment period. In addition, the patient was asked to rest the day the grafts were applied and for 2 days after application.

On the tenth day following the last application of the autologous keratinocytes, the dressing regimen of hyaluronic acid covered with polyurethane foam was resumed. These dressings were changed twice a week.

Complete wound closure was achieved 60 days following the first fibroblast application. The application of fibroblasts appeared to allow the formation of well-vascularized granulation tissue in a wound bed that contained no granulation tissue when only advanced medications were being used. Rapid activation of re-epithelialization from the wound margins was observed after keratinocyte application.

The patient continued to come to the clinic for regular monthly check-ups. Rigid (rocker bottom) shoes and insoles made from plantar molds were provided. The treated lesion remained re-epithelialized. The newly formed epithelium integrated completely with the surrounding skin (see Figure 5). At this time, exact information about the cost of treatment with these autologous cells is not available but, for this specific case, the cost was estimated to be approximately $1,000 (US).

Limitations

The technique described requires time to culture the cells. Furthermore, this case study represents only one successful approach to a clinically challenging situation. The results obtained may be due more to the effect of the hyaluronic acid or the cultured fibroblasts and keratinocytes; this has not been ascertained.

Conclusions

This experience suggests that the use of autologous fibroblasts and keratinocytes cultured on biodegradable hyaluronic acid-derived scaffolds could be a rational approach for the treatment of severe chronic wounds of the lower limbs in patients with diabetes. The use of this novel tissue-engineering technique is currently under investigation in randomized controlled clinical studies. - OWM