title: HLA-B27 antigen and rheumatoid factor negative (seronegative) peripheral arthritis. Studies in younger patients with early-diagnosed arthritis.
mesh_terms: D000293:Adolescent; D000328:Adult; D001168:Arthritis / Q000276:immunology*; D001172:Arthritis, Rheumatoid / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006680:HLA Antigens; D006649:Histocompatibility Antigens; D006801:Humans; D007249:Inflammation / Q000276:immunology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012217:Rheumatoid Factor; D012446:Sacroiliac Joint / Q000276:immunology
chemical_list: D006680:HLA Antigens; D006649:Histocompatibility Antigens; D012217:Rheumatoid Factor