[Clinical activity and serum immunoglobulin concentrations in patients with ankylosing spondylitis].

Several authors have suggested that immunoglobulin A plays a pathogenic role in ankylosing spondylitis. We have determined the levels of immunoglobulins in 30 patients, observing higher levels than in control patients (248 vs 176 mg/dl); p less than 0.01) and a relation between the increase of immunoglobulin A and the presence of clinical activity in the subgroup of patients B27-negative (163 vs 398 mg/dl, p less than 0.005), but not in B27-positive patients. We think that these e results support the hypothesis that ankylosing spondylitis is an heterogeneous disease, with different pathogenic mechanisms depending on the presence or absence of the serological marker HLA-B27.