RHEUMATOLOGY National Rheumatoid Arthritis Society NHS.UK Rheumatic-fever John Hopkins Arthritis Center : Ankylosing Spondylitis Biomed Central Pediatric Rheumatology Rheumatoid Arththritis.org MedlinePlus: Arthritis MedlinePlus: Rheumatoid Arthritis MedlinePlus: Rheumatic Fever see Streptococcal Infections MedlinePlus: Rheumatoid Spondylitis see Ankylosing Spondylitis WebMD: Arthritis Health Center International Journal of Rheumatology American College of Rheumatology Arthritis Foundation Arthritis National Research Foundation Healthfinder™ NIAMS Pediatric Rheumatology European Association International Journal of Rheumatology