[Perthes disease: immunological aspects.]

The values of cellular, humoral immunity, cytokine status, those of phagocytic activity of neutrophils (PAN) have been studied in patients with Perthes disease II and III Stages. Considering a stage of the pathological process patients (boys at the age of 8-12 years) were divided into two (2) groups. Group I included 14 patients with the fragmentation stage (Perthes disease Stage II). Group 2 include d 15 children with Perthes disease Stage III (the stage of re-ossification). Perthes disease regardless of the stage of the disease was characterized by the increase in oxygendependent and lysosomal phagocytic activity of neutrophils, the increase in the number of early extracellular traps, as well as by increased concentrations of pro-inflammatory cytokines (IL-1β and TNFa), IgЕ, decreased concentrations of IL-18. The fragmentation stage was characterized by moderate activation of cellular immunity with a prevailing increase in the number of T-lymphocytes with early activation markers (CD25). At the re-ossification stage the predominance of T-lymphocytes was observed with late activation markers (HLADR), being accompanied by moderate activation of humoral immunity (increased concentrations of class A and G serum immunoglobulins). The obtained data can be used as additional criteria for clarifying Perthes disease stage, predicting osteonecrosis development when making decision of the feasibility of performing reconstructive surgeries on the joint.