[Remarkable improvement of the hip joint lesion in a patient with rheumatoid arthritis by the treatment with anti-TNF-α agents].

22-year old woman who was previously diagnosed as having juvenile idiopathic arthritis (JIA) was treated with anti-TNF-α agents. Her disease activity was assessed as Stage IV and Class III by Steinbrocker's classification and resistant to steroids and methotrexate. Initially clinical findings responded well to infliximab (IFX), but polyarthritis recurred 15 months after the start of the treatment, and IFX was switched to etanercept (ETN) with good response. On the other hand, effects on the osteoarticular lesions were continuously observed through the period of the treatment with these two biologics. It was thought very rare that weight-bearing joint like the hip joint was restored as was seen in this case, while its mechanism is unknown. Because mechanism for inhibition of inflammation or joint destruction might be independent, we should investigate further the relationship between inflammation and joint destruction in the future.