Osteonecrosis is a relatively common complication in systemic lupus erythematosus (SLE) patients. OBJECTIVE: To evaluate the possible risk factors associated with osteonecrosis in SLE patients. METHODS: SLE patients [according to American College of Rheumatology (ACR) criteria] who presented osteonecrosis were included in this study. SLE patients with no symptomatic osteonecrosis constituted the control group. Osteonecrosis was confirmed by radiographic evaluation, bone scintigraphy and/or magnetic resonance imaging. RESULTS: The study group was constituted by 14 SLE patients with osteonecrosis (10 women and 4 men, 64% of them white, 33 ± 13 years old and 120 ± 67 months of disease duration). Sex and time of SLE diagnosis matched patients without osteonecrosis constituted the control group (n = 14, 57% of them white, 33 ± 7 years old and 111 ± 54 months of SLE). Systemic lupus international collaborating clinics/ACR damage index for SLE (SLICC/ACR-DI) score was higher in patients with osteonecrosis (4 ± 1) compared with control group (1 ± 1) [p < 0.001]. Patients with osteonecrosis had higher number of other musculoskeletal irreversible damage when compared with the control group (29% versus 0, respectively; p = 0.034). Digital vasculitis was the variable associated with osteonecrosis (p = 0.021). There was no significant association between duration of prednisone use or prednisone cumulative dose and osteonecrosis in patients with regular follow-up at the Institution (p = 0.624 and p = 0.806, respectively). CONCLUSIONS: Previous history of digital vasculitis was a risk factor for the development of osteonecrosis. Patients with digital vasculitis history had 9 times more risk to present osteonecrosis than patients without previous vasculitis.
systemic lupus erythematosus; osteonecrosis; risk factors; vasculitis
