AB0929 CALCIUM PYROPHOSPHATE DIHYDRATE CRYSTAL-DEPOSITS: REMEMBER THE SPINE!
Authors: D. Khalifa, K. Baccouche, N. El Amri, H. Zeglaoui, E. Bouajina
Journal: Annals of the Rheumatic Diseases (2020)

Background: Calcium pyrophosphate dihydrate crystal-deposits (CPPD) is a common crystal disease affecting men and women equally. It is normally seen in peripheral joints. Spine involvement is rare and may mislead the diagnosis. Objectives: To describe clinical, radiological and therapeutic findings of CPPD of the spine. Methods: A retrospective descriptive study was conducted in the rheumatology department of Farhat Hached Hospital, including patients diagnosed with CPPD of the spine over a period of 20 years (1998-2018). Data concerning clinical, radiological and therapeutic aspects of CPPD of the spine were callected from their medical files. Results: Twelve patients had a spinal localisation of CPPD. The mean age was 59.91±16.21 years. Patients were mainly women with a sex ratio men/women of 1:3. Mean duration of symptoms before the diagnosis was 27.08±25.69 months. Spinal presentation was the revealing symptom of CPPD in 45.5% of the cases. It affected the cervical spine in 66.7% and the lumbar spine in 33.3% of the cases. Spinal localisation of CPPD was associated with a peripheral arthropatyhy in 75% of the cases (the knees in 41.7%, wrists and hands in 66.6%, shoulders in 25% and the hips in 16.7%). Discovery of spinal CPPD was coincidental on plain radiographs in 16.7% of the cases. When symptomatic, the disease manifested itself as inflammatory pain in 72.7%, mechanical pain in 9.1% and both diurnal and nocturnal pain in 18.2% of the cases. Physical examination revealed stiffness of the spine in 58.3% of the patients. Fever was noted in 8.3% and deterioration of general condition with anorexia was reported in 25% of the patients. Neurological complications were represented by cervical myelopathy in 25%, sciatica in 8.3% and a case of unilateral ulnar nerve neuropathy was reported. Laboratory tests revealed inflammation in 50% of the cases. However, crystals were present in synovial fluid in only 25% of the patients. Spinal CPPD was visible on plain radiographs in 83.3% of the cases, showing calcified discs in 75% and signs of destruction in 16.7% of the cases. Peripheral calcifications were present in the wrists in 33.3% and the knees in 58.3% of the cases. Crow dens syndrome was reported in 16.7% of the patients. CT-scan helped the diagnosis of calcifications and crown dens syndrome when performed. MRI was prescribed in 58.3% of the patients and characterized the cervical myelopathy. Treatment relied on analgesics in all patients, NSAIDS were prescribed in 83.3%, colchicine in 66.7% and general corticosteroids in 25% of the cases. Spinal immobilization was recommended in 25% of the cases for a short period. Spinal CPPD was idiopathic in 75%, secondary to hyperparathyroidism in 8.3% of the cases and familial cases were detected in 16.7% of the patients. Conclusion: Axial CPPD is rare and is an under-recognized entity that should be considered in elderly patients with neck or back pain. It can involve the discs or ligaments. The crown dens syndrome is quite suggestive of the diagnosis. If spinal CPDD is suspected, colchicine therapy could be a good therapeutic test and would avoid unnecessary further tests. References: [1]Ferrone C, Andracco R, Cimmino MA. Calcium pyrophosphate deposition disease: clinical manifestations. Reumatismo. 19 janv 2012;63(4):246‑52. [2]Feydy A, Lioté F, Carlier R, Chevrot A, Drapé J-L. Cervical spine and crystal-associated diseases: imaging findings. Eur Radiol. févr 2006;16(2):459‑68. Disclosure of Interests: None declared