In contrast, and aligned with recent studies (20, 48) demonstrating an association between PTX3 circulating levels and the progression of joint damage in RA, osteoporosis and osteoarthritis bone phenotype, we confirmed that PTX3 serum levels measured at the onset of RA and prior to treatment modification correlates with radiographic damage observed at 12 months follow-up. Here, PTX3 is linked to osteoporosis.