[A case report of systemic calcinosis associated with rheumatoid arthritis]

A 69-year-old female with a fourty-year history of rheumatoid arthritis visited Kobe University hospital with complaints of subcutaneous soft tumor on both hands and arthritic pain of both knees. She has been given 10 mg of predonisolone for several years and had a history of hydronephrosis. Her radiographs revealed periarticular calcification in the hands, shoulder joints and posterior thoracic wall. She had high titer of rheumatoid factor and both erythrocyte sedimentation rate (79 mm/hr) and C-reactive protein (12.79 mg/ml) were elevated. The examination of her serum showed the following values: Ca 7.9 mg/dl, P 5.0 mg/dl, 25 (OH) D3 < 3.6 pg/ml, 1 alpha-. 25 (OH)2 Vit D3 < 6.1 pg/ml, osmolality 974 mOsm/kg, BUN 61 mg/dl, creatinine 1.9 mg/ml, creatinine clearance less than 20 ml/min, indicating chronic renal failure. Intact PTH level was normal, although plasma parathyroid hormone-C (PTH-C) level increased. Together with these findings, it is suggested that metabolic disorders associated with chronic renal failure and tissue damages due to the severe rheumatoid arthritis led to the formation of diffuse soft tissue calcification.