Spinal involvement with calcium pyrophosphate deposition disease in an academic rheumatology center: A series of 37 patients.

BACKGROUND: Calcium pyrophosphate dihydrate deposition disease (CPPD) has been reported to involve the spine, but few systematic studies have been published.

OBJECTIVE: To further characterize the spinal involvement with CPPD by a review of CPPD patients hospitalized in a rheumatology department.

METHODS: We retrospectively reviewed data for patients consecutively admitted with a diagnosis of CPPD in the rheumatology department of Lariboisière hospital in Paris, France over 5 years by using a standardized protocol and electronic case report forms. Imaging studies were also reviewed.

RESULTS: Spinal CPPD was diagnosed in 37/152 (24.3%) CPPD patients. Patient with spinal involvement had more widespread peripheral CC. The cervical (n = 21) and lumbar (n = 19) segments were most involved. CT-scan was more sensitive than plain radiographs for detecting spinal calcifications. Crown dens syndrome was a prominent feature of cervical involvement. Inflammatory sterile spondylo-discitis was observed in 6 patients. Lesions were frequently multiple and were classified into 4 types. Ruling out septic discitis required image-guided biopsies in 3 patients. Sacroiliac involvement included calcification in 5 patients and severe sterile destructive arthropathy and joint fusion in one patient each. Degenerative changes were common, and CPPD could not be implicated because of the patients 'age and lack of a control population. In 12 patients, severe clinical features requiring hospitalization were related to such degenerative changes.

CONCLUSION: Symptomatic involvement of the spine was observed in 24% of this series of hospitalized CPPD patients. Specific entities were the cause of hospitalisation in 25 of the 37 patients with spinal calcification and included inflammatory pain related to crystal deposits and destructive arthropathy of the spine and sacroiliac joints. Discitis exhibited a wide range of MRI features and biopsies were needed to rule out infection in 3 of the 6 discitis.