Axial bone involvement in sarcoidosis

Introduction. - Sarcoidosis is a multi-systemic disease characterized by non-caseating granulomas. Bone involvement initially considered as rare and described as a peripheral osteitis of the hands and feet, has recently been reported on the axial skeleton. Case reports. - We report 4 clinical observations of sarcoidosis (3 women, 1 man) with axial bone involvement located to the spine (n = 4), pelvic bone (n = 2), scapular bone (n = 2), sternum (n = 1), mandible (n = 1). Sarcoidosiswas already diagnosed in 3 cases. Bone painwas themain symptom, related in 3 cases. Magnetic resonance imaging appeared to be the best imaging test Histological bone analysis revealed typical granulomatous lesions (n = 2). Treatment included corticosteroids (n = 4), hydroxychloroquine (n = 2), and methotrexate (n= 2), with a good efficacy on bone pain in symptomatic patients. Conclusion. - These 4 cases, as well as recent literature, illustrate bone involvement of sarcoidosis on the axial skeleton. It is symptomatic in around 50% of cases but may be a source of significant disability. Differential diagnosis with neoplasm may require bone histological analysis. This condition appears to be responsive to usual treatments for sarcoidosis. (C) 2020 Societe Nationale Francaise de Medecine Interne (SNFMI). Published by Elsevier Masson SAS. All rights reserved.