Background Various reports was made for biological drug impacts on pathological findings in rheumatoid arthritis (RA) synovial tissue. However the impact of the biologics on the synovial tissure is not unclear.
Objectives We examined biological drug impacts on RA synovial tissues based on pathological findings in them collected during surgeries for the same patient before and after biological drug usage.
Methods Synovial tissues were collected from 17 RA joints before and after biological drug usage. Inflammatory change in synovial tissues collected during surgeries was assessed by Rooney score. We examined correlation between pathological findings in RA synovium and disease activity under biological drug usage. Disease activity was assessed by CDAI. Etanercept, Infliximab and Tocilizumab was used as biological drug for 10, 5 and 2 joints respectively.
Results Rooney score between before and after biological drug usage improved from 27.4 to 12.8 showing significant difference. Significant improvement in Rooney score was observed in all items. In remission and low groups after biological drug usage, Rooney score significantly decreased in items of synovial lining cells, perivascular lymphocytic infiltration, lymph follicle and lymphocytic infiltration. Significant difference in Rooney score was not observed in moderate group between before and after biological drug usage.
Conclusions With decrease observed in single layer formation in synovial lining cells, angiogenesis in sub-synovial tissue, perivascular lymphocytic infiltration and lymph follicle, improvement in inflammatory change in synovium was achieved. Pathological findings in sub-synovial tissue suggested to have reflected disease activity.
Disclosure of Interest None declared