J Rheum Dis 2016; 23(2): 125-129  
A Case of Acute Calcium Pyrophosphate Crystal Arthritis in the Lumbar Facet Joint
Sang Wan Chung1, Jong Jin Yoo2, Joon Woo Lee3, You-Jung Ha1, Eun Ha Kang1, Yeong Wook Song4, Yun Jong Lee1,4
1Division of Rheumatology, Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, 2Department of Internal Medicine, Kangdong Sacred Heart Hospital, Seoul, 3Department of Radiology, Seoul National University Bundang Hospital, Seongnam, 4Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
Correspondence to: Yun Jong Lee
Division of Rheumatology, Department of Internal Medicine, Seoul National University Bundang Hospital, 82 Gumi-ro, 173 beon-gil, Bundang-gu, Seongnam 13620, Korea. E-mail:yn35@snu.ac.kr
Received: May 21, 2015; Revised: June 29, 2015; Accepted: June 30, 2015; Published online: April 30, 2016.
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Calcium pyrophosphate dihydrate deposition disease most commonly presents with acute arthritis of the peripheral joints. Infrequently, a mass effect of this disease can cause axial symptoms, such as spinal stenosis, radiculopathy, or myelopathy. Herein, we report on the first Korean case of acute arthritis in the lumbar facet joint due to calcium pyrophosphate dihydrate crystal deposition disease. A 73-year-old female presented with acute fever, severe lumbago, and knee arthralgia, 11 days after partial parathyroidectomy. Plain radiographs showed multiple chondrocalcinosis, while a bone scan, computed tomography, and magnetic resonance imaging showed right L5-S1 facet arthritis. In synovial fluid from the facet and knee joints, positively birefringent calcium pyrophosphate dihydrate crystals were observed under polarized light microscopy. Under the diagnosis of acute calcium pyrophosphate dihydrate crystal arthritis (formerly known as ‘pseudogout’) in the facet joint, an intra-articular triamcinolone injection was administered, which resulted in dramatic improvement of the symptoms within 24 hours. (J Rheum Dis 2016;23:125-129)
Keywords: Calcium pyrophosphate dihydrate deposition, Chondrocalcinosis, Zygapophyseal joint, Low back pain

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