혈청음성 류머티스관절염으로 오인된 색소성 융모결절윤활막염 1례

Abstract

Pigmented villonodular synovitis is a uncommon benign proliferative disorder affecting the synovial membrane of joint, bursa and tendon sheath. The etiology is not apparent, however chronic inflammation and trauma may be the cause. The preferred lesions include joints of the lower extremity, especially the knee or hip, and commonly involves one joint. The presented case is a 23-year-old female with right knee pain and swelling for 2 years. Initially, she was diagnosed as seronegative rheumatoid arthritis. After medical treatment, however her symptom was not resolved. Arthrocentesis of her right knee showed bloody effusion, therefore we performed knee MRI arthroscopy for further evaluation. Knee MRI showed bursitis with synovial cysts, synovitis, joint effusion and bone erosion. On arthroscopy, yellowish-brown colored hypertrophied synovium was noted, and arthroscopic synovectomy was performed. Histologically, fibrous stroma, hemosiderin deposits, multinucleated giant cell and foam cells were found. Biopsy result was consistent with pigmented villonodular synovitis.