Osseous sarcoidosis: clinical characteristics, treatment, and outcomes--experience from a large, academic hospital.

Objective: Osseous sarcoidosis has been infrequently reported. We aimed to characterize the distribution of lesions, clinical presentation, treatment, and outcomes for osseous sarcoidosis.

Methods: Cases of osseous sarcoidosis were identified by directed inquiry to clinicians and electronic query. Cases were defined as having pathologic evidence of non-caseating granulomas on bone biopsy or evidence of osseous lesions on imaging attributable to sarcoidosis in patients with known sarcoidosis. Detailed characteristics were obtained by medical record review.

Results: We identified a total of 20 cases of osseous sarcoidosis. Osseous lesions were detected by imaging during the initial sarcoidosis presentation in 60% of cases. In those who had a prior diagnosis of sarcoidosis, the median duration of sarcoidosis before detection of osseous involvement was 4.3 years. Symptoms were present in 50% of cases. All cases had more than one bone involved. The axial skeleton was involved in the majority of cases (90%), primarily the pelvis and the lumbar spine. Most cases required no treatment (55%); a minority of cases (45%) were treated, most often with prednisone, methotrexate, or hydroxychloroquine. Two cases required multiple immunosuppressants, including tumor necrosis factor inhibitors, for refractory symptomatic osseous sarcoidosis. Treated cases were younger than those who were untreated. At last follow-up, most cases (85%) were asymptomatic from osseous lesions.

Conclusions: In this case series of osseous sarcoidosis from a single center, most patients had multiple bones affected and had other systemic manifestations of sarcoidosis. A minority required treatment for relief of symptoms, and most cases were asymptomatic at last follow-up.