Concomitant axial ankylosing spondylitis and Paget's disease.

The case of a patient who had both Paget's disease and axial ankylosing spo ndylitis is reported. Sacroiliac joint lesions can be caused by either or b oth conditions. It follows that the diagnosis of axial ankylosing spondylit is in a patient with Paget's disease should rest on strict criteria that do not take into account radiological evidence of sacroiliitis (criteria deve loped by Baudouin, and Landureau) or on Amor's criteria.