title: Ankylosing spondylitis and chlamydial infection in apparently healthy HLA B27 blood donors.
mesh_terms: D000328:Adult; D000907:Antibodies, Bacterial; D016918:Arthritis, Reactive / Q000209:etiology / Q000276:immunology; D001416:Back Pain / Q000150:complications; D001782:Blood Donors; D002690:Chlamydia Infections / Q000150:complications / Q000276:immunology*; D005260:Female; D006680:HLA Antigens; D006801:Humans; D008213:Lymphocyte Activation; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012446:Sacroiliac Joint / Q000000981:diagnostic imaging; D013167:Spondylitis, Ankylosing / Q000150:complications / Q000000981:diagnostic imaging / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial; D006680:HLA Antigens