[Diagnosis and treatment of rheumatoid arthritis:toward the best practice. Anti-bone resorbing treatment for rheumatoid arthritis.]

Rheumatoid arthritis(RA)is a systemic inflammatory disease characterized by chronic synovitis and bone damage. The imbalance in immune system and its mediated chronic inflammation result in pathological processes such as joint destruction as well as secondary osteoporosis. Proinflammatory cytokines such as TNF and IL-6 cause an imbalance in bone metabolism via direct and/or indirect effects on osteoclasts. However, biologic DMARDs targeting TNF and IL-6 have revolutionized the treatment of RA, producing significant improvements in clinical and structural outcomes that were not previously observed. An anti-RANKL antibody denosumab inhibits osteoclast-induced bone resorption by preventing the binding of RANKL and improves osteoporosis in cortical as well as trabecula bone. In the DRIVE study denosumab inhibited the progression of bone erosion in Japanese patients with RA. Thus, differential efficacy of different therapies in bone destruction and osteoporosis would warrant further study to clarify the mechanisms of bone and joints diseases.