J Rheum Dis 2016; 23(5): 316-320  
A Case of Idiopathic Massive Rice Bodies in the Knee Joint without Rheumatoid Arthritis or Tuberculosis and a Literature Review
Whan Yong Chung1, Ji-Sun Song2, Hwa Eun Oh3, Hee Jin Park4
Departments of 1Orthopedics, 2Pathology, and 4Rheumatology, Catholic Kwandong University International St. Mary’s Hospital, Incheon, 3Department of Pathology, Korea University Ansan Hospital, Ansan, Korea
Correspondence to: Hee Jin Park, Department of Rheumatology, Catholic Kwandong University International St. Mary’s Hospital, 25 Simgok-ro 100beon-gil, Seo-gu, Incheon 22711, Korea. E-mail:yolliko@ish.ac.kr
Received: November 19, 2015; Revised: December 23, 2015; Accepted: December 24, 2015; Published online: October 31, 2016.
© Korean College of Rheumatology. All rights reserved.

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Rice bodies are materials with an amorphous nucleus and a fibrin layer found floating in the synovial space and bursa. These bodies have often been detected in patients with rheumatoid arthritis, tuberculous arthritis, and bursitis. Although the etiology and pathogenesis of rice bodies are not yet fully understood, it has been hypothesized that they might be caused by chronic inflammation originating from the synovium. However, we report on a case of idiopathic massive rice bodies in the knee joint without evidence of inflammatory articular disease or infection including rheumatoid arthritis, seronegative spondyloarthritides, tuberculosis, or bacterial or fungal infection.
Keywords: Rice body, Knee, Rheumatoid arthritis, Tuberculosis

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