title: Letter: HL-A W27, spondylitis and enteritis.
mesh_terms: D003093:Colitis, Ulcerative / Q000453:epidemiology; D003424:Crohn Disease / Q000453:epidemiology; D004751:Enteritis / Q000453:epidemiology* / Q000276:immunology; D006649:Histocompatibility Antigens / Q000032:analysis*; D006801:Humans; D013167:Spondylitis, Ankylosing / Q000453:epidemiology* / Q000276:immunology
chemical_list: D006649:Histocompatibility Antigens