Immunohistochemical evaluation of venous leg ulcers before and after negative pressure wound therapy

Venous leg ulcers represent a medical challenge. Whenever possible, therapy should be causal and include compression therapy and surgery. Negative pressure wound therapy (NPWT) has been successfully used in several phases of venous leg ulcer treatment. Positive effects of NPWT, such as reduction of edema, drainage of wound exudate, and ac- celeration of granulation tissue formation, are reasons for recommending NPWT in order to improve healing rates.

The main goal of this study was to evaluate, using immunohistochemical markers, the efficacy of NPWT in terms of neoangiogenesis and granulation tissue promotion in the treatment of hard-to-heal venous leg ulcers.

Thirty patients with hard-to-heal venous leg ulcers were included. The patients were divided into two groups: one group treated with NPWT, polyurethane foam, and four-layer bandaging system, and the second group with moist wound dressings and four-layer bandaging system. Patients were moni- tored before and after 1 week of treatment with multiple biopsies taken from the wound bed and wound edge. Immunohistochemical evaluation included markers for angiogenesis (CD31), lymphatic vessels (D240), macrophages (CD68), and lymphocytes (CD3).

All patients in- cluded in the NPWT group, after 1 week, showed a significant improve- ment in terms of angiogenesis, lymphatic vessels, and macrophage and lymphocyte proliferation, compared to the control group.

This study objectively demonstrated the efficacy of NPWT in hard-to- heal venous leg ulcers via immunohistochemical findings. In particular, the results showed rapid granulation and neoangiogenesis promotion. In the authors' opinion, NPWT must be included as an adjuvant to standard venous leg ulcer therapy.