A Case of Acute Calcium Pyrophosphate Crystal Arthritis in the Lumbar Facet Joint

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) KCI Citation Count: 0