title: Seronegative spondarthritis.
mesh_terms: D006680:HLA Antigens / Q000276:immunology; D006801:Humans; D012217:Rheumatoid Factor / Q000276:immunology; D013167:Spondylitis, Ankylosing / Q000276:immunology*
chemical_list: D006680:HLA Antigens; D012217:Rheumatoid Factor