The seronegative spondyloarthropathies.
D006801:Humans; D007592:Joint Diseases / Q000097:blood* / Q000276:immunology; D012698:Serologic Tests; D013122:Spinal Diseases / Q000097:blood* / Q000276:immunology; D013167:Spondylitis, Ankylosing / Q000097:blood / Q000276:immunology*