Inclusion of fibrinoid necrosis increases the accuracy of synovial tissue assessment in predicting response to methotrexate: analysis of the UCLouvain Brussels ERA Cohort.

Objective: Rheumatoid Arthritis (RA) often exhibits suboptimal treatment response despite early diagnosis and treatment. This study aimed to analyze Early Rheumatoid Arthritis (ERA) synovial biopsies through histology and immunohistochemistry (IHC) to identify predictive factors for treatment response to Methotrexate (MTX).

Methods: 140 ERA patients from the UCLouvain Arthritis Cohort underwent synovial biopsy and were monitored after initiating Disease-Modifying Antirheumatic Drug (DMARD) therapy.