[The immunological aspects of a hip joint lesion in childhood]

Area of Science:

• Pediatric Immunology
• Rheumatology
• Cellular Biology

Background:

• Hip joint synovitis in children encompasses various conditions, including transient synovitis, Perthes disease, and tuberculous coxitis.
• Understanding the underlying immunological mechanisms is crucial for effective diagnosis and treatment.

Purpose of the Study:

• To analyze and compare the immunological mechanisms involved in the development of hip joint synovitis in pediatric patients.
• To elucidate the specific immune cell subpopulations and pathways affected in transient synovitis, Perthes disease, and tuberculous coxitis.

Main Methods:

• Flow cytometry (FACStar PLUS) was used to analyze immunocompetent cell subpopulations.
• Immunological parameters were compared between pediatric patients with different types of synovitis and age/sex-matched controls.
• Specific markers and immune responses, including T-cell and B-cell activity, serum IgA, and natural killer cell activity, were assessed.

Main Results:

• Transient synovitis appears to have toxic-and-allergic origins, characterized by T-helper cell dysfunction and T-suppressor cell activation, alongside reduced serum IgA.
• Non-specific immune mechanisms, such as natural killer cell activity and SDH activity, showed compensatory increases.
• Perthes disease requires further investigation into cell activation mechanisms (e.g., CD4+ antigen expression).
• Tuberculous coxitis is associated with immunological incompetence, cytotoxic reactions, and increased IgM production without significant IgG changes.

Conclusions:

• Transient synovitis involves a specific T-cell mediated immune response.
• Tuberculous coxitis presents with a distinct pattern of immune incompetence and B-cell activation.
• Treatment strategies for tuberculous coxitis should consider selective T-helper stimulators and immunomodulatory drugs targeting the T-cell link.