title: Coexisting seronegative rheumatoid arthritis and ankylosing spondylitis.
authors.forename: Hakan
authors.initials: H
authors.lastname: Genc
authors.forename: Bariş
authors.initials: B
authors.lastname: Nacir
authors.forename: Meryem
authors.initials: M
authors.lastname: Saracoğlu
authors.forename: H Rana
authors.initials: HR
authors.lastname: Erdem
mesh_terms: D001172:Arthritis, Rheumatoid / Q000150:complications* / Q000175:diagnosis*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D018570:Risk Assessment; D012698:Serologic Tests; D012720:Severity of Illness Index; D013167:Spondylitis, Ankylosing / Q000150:complications* / Q000175:diagnosis*