Ankylosing spondylitis in women

Although ankylosing spondylitis (AS) has been considered rare in women, we believe that its incidence is underestimated. In our case studies of 12 women with AS the characteristic clinical features of the disease included onset before the age of 30 (12 patients); night pain and morning stiffness (12 patients); intermittent, migratory joint pain (9 patients); and history of uveitis (2 patients). Spine mobility was decreased in all patients. Sacroiliac (SI) (8 patients) and circumthoracic (5 patients) tenderness were common findings. If these pertinent clues are present, further diagnostic studies are indicated. Histocompatibility testing for the HLA-B27 antigen, which is reported to be present in over 90% of patients with AS, is useful in detecting early and mild forms of the disease. We found the antigen in 10 of 11 patients tested. Radioisotope (RI) scanning can show early inflammation of the SI joints long before changes are evident on standard roentgenograms: In 3 cases, SI films were reported as normal but RI scans revealed abnormal uptake and ratios. Early detection of AS prevents inappropriate treatment of patients and mislabeling them as functional complainers.