Clinical study of T lymphocyte subsets and several biological indicators in children with transient synovitis.

Background: This study aimed to analyze T lymphocyte subsets and several biological indicators in children with transient synovitis (TS) to provide insights for subsequent diagnosis and treatment.

Methods: We retrospectively studied 126 patients admitted to Changchun Children's Hospital from May 2020 to August 2023 with suspected acute TS or bone and joint infections (BJIs). The study comprised two parts: (1) description and analysis of clinical and laboratory features of all patients under 16 years old ; (2) comparison of laboratory data between children with TS and a control group of children undergoing elective surgery. Univariate analysis was used to determine the significant differences. Linear regression analysis was used to analyze the correlation between the variables in the study.

Results: Among the 126 patients, 121 were diagnosed with TS and 5 with BJIs. We analyzed the clinical and laboratory features of these children. Most patients achieved remission after treatment. In children with transient synovitis of the hip (TSH), the amount of joint effusion was negatively correlated with the CD4 + T lymphocyte count. Median IL-6 levels were significantly higher in TSH children with a preceding upper respiratory infection (URI) compared to those without.

Conclusions: Alterations in T lymphocyte subsets, particularly CD4 + count, may be associated with joint effusion volume in TSH. Detection of T lymphocyte subsets and several specific biomarkers (IL-6, TNF-α, IL-2) reflects the changes of immune status in children with TS, potentially aiding clinical assessment.