[Influence of connective tissue differentiation on scar tissue formation in children].

OBJECTIVE To study the immunohistochemical features of various scar tissues in children without connective tissue pathology and with undifferentiated connective tissue dysplasia syndrome. MATERIAL AND METHODS Tissue biopsy was performed in 217 children who underwent surgical treatment for various lesions, such as injuries, burns, as well as other procedures. There were 127 boys (58.5%) and 90 (41.5%) girls. The main group consisted of 98 (48.2%) children with scar tissue; group of UCTD syndrome - 65 (30.0%) children; control group - 43 (24.8%) patients without pathological scars. Histological examination of scar tissue and intact skin was carried out during primary or redo reconstructive surgery. Immunohistochemical study of antibodies against CD34, CD105, CD140b, PDGFs, COL types I, III and IV was performed. RESULTS The study showed a quantitative characteristic of expression of COL type I in hypertrophic scar with predominance in the main group (77.5±5.4%; p<0.05), and decrease in COL type IV. Keloid form was associated with predominance of granulation tissue in all layers of dermis and high levels of all types of collagen. In the group of UCTD, COL type III prevailed in all pathological forms of the scar. We determined quantitative indicators of expression of vascularization factors (CD34; CD105) and fibroblastic activity (CD140b; PDGFs). CONCLUSION Understanding the process of fibrinogenesis and analysis of stages of triggering mechanisms are essential for development of preventive algorithms. Individualized approach should be considered in the treatment. These studies are especially important in children with UCTD syndrome as high-risk group for pathological scarring. Thus, further research is required.