Synovial microenvironment and fluorescence imaging for early rheumatoid arthritis diagnosis.

Rheumatoid arthritis (RA) is a chronic, systemic autoimmune inflammatory disease that primarily affects the joints and surrounding soft tissues. Early diagnosis is crucial for preventing joint damage and improving the prognosis and quality of life in RA patients. Therefore, this article reviews conventional diagnostic methods, such as serologic tests (including rheumatoid factor (RF), anti-citrullinated protein antibody (ACPA), and anti-carbamylated protein (anti-CarP)) and imaging tests and also focuses on innovations in AI-driven diagnostic and therapeutic technologies. Additionally, we provide insights into new biomarkers (including macrophages, neutrophils, and synovial fibroblasts) in the synovial microenvironment that correlate with RA disease activity and severity at the molecular level. Importantly, we are optimistic about fluorescence imaging (FOI) techniques (including visible light imaging and near-infrared (NIR)-FOI), which can accurately quantify abnormal levels of molecular markers using fluorescent probes. This provides detailed information about pathological changes in RA, opening new horizons for early diagnosis and treatment.