Cytokine profile of synovial fluid children with Legg-Calve-Perthes disease and transient synovitis of the hip

Background. The nature of synovitis development in the early stages of Legg-Calve-Perthes disease (LCPD), some issues of the pathogenesis of further osteodestructive processes remain not fully known. At the same time, a targeted treatment option for hip osteochondropathy should be based on a complete understanding of the dysregulation of osteogenesis at the molecular and cellular level. Thus, knowledge about the patterns of changes in the molecular composition of synovial fluid during the induction of osteodestruction in the case of LCPD can serve as the basis for the introduction of new diagnostic criteria for this pathology and strategies for its treatment, including the use of genetically engineered drugs. Aim. To perform a comparative analysis of the concentration of immunoregulatory molecules in synovial fluid in patients with Legg-Calve-Perthes disease in relation to transient hip synovitis. Materials and methods. The concentration of five mediators/chemokines/cytokines (CD40, MDC/CCL22, Fractalkin (CX3CL1), IP10/CXCL10, VEGF) in synovial fluid was analyzed in 42 children diagnosed with transient synovitis of the hip (TS), as well as in 26 patients diagnosed with stage 2 BLCP disease, according to the Waldenström classification. Results. The performed study indicates the different nature and nature of synovial inflammation with favorably occurring TS and LCPВ. The concentration of regulatory molecules in synovial fluid depends on the leading etiological factor and can influence the processes of osteoresorption and osteogenesis. Thus, changes in cytokine activity in patients with BLCP indicate the importance of disorders in the coupling of angiogenesis and osteogenesis at the molecular and cellular level. An increase in the concentration of phosphoprotein CD40 against the background of the induction of VEGF glucoprotein proliferation is associated with the activation of inflammation in vascular disorders. At the same time, with the development of TS, there was an increase in the level of cytokine IP10, which regulates the Th1 immune response. Conclusions. In TS, the leading factor is the immune-inflammatory response with activation of the chemokine system. The manifestation of inflammation in LCPD is associated with disturbances in the coupling system of angiogenesis and osteogenesis at the molecular and cellular level, and increased expression of inflammatory mediators.