Aleksandra Lesiak, Joanna N
Necrobiosis lipoidica (NL) and granuloma annulare (GA) belong to the granulomatous skin diseases with unclear pathogenesis. Despite the quite common occurrence of these entities in dermatological practice, research into the subject is limited. Thus, we decided to perform an immunohistochemical analysis of skin biopsies in order to assess the expression of selected proteins involved in angiogenesis. The study group consisted of 21 patients with NL and 23 with GA, selected from the database at the Department of Dermatology, Medical University of Łódź. Six healthy subjects served as the controls. Skin sections were stained with monoclonal antibodies directed against VEGF and CD34. The intensity of expression of epidermal VEGF, and the number of CD34+ dermal blood vessels were assessed. The mean intensity of VEGF immunoexpression in GA patients was 0.91, and was significantly higher than in either the NL patients (0.45; p<0.01) or the control group (0.14; p<0.009). The mean CD34+ microvessel density per mm2 in the GA group was 79.04, which was significantly higher than in the NL group (64.84; p<0.009) and in the controls (52.03; p<0.001). The obtained results confirm the similarity of the histological features of NL and GA. However, in GA, the biopsy changes in angiogenesis were more marked in the GL than in the NL group. In conclusion, based on our results we can assume that imbalance in the process of angiogenesis is one the factors involved in development of both NL and GA.