title: Long-term outcomes of destructive seronegative (rheumatoid) arthritis - description of four clinical cases.
abstract: Seronegative rheumatoid arthritis is associated with a milder course of progression compared to seropositive disease. However, long-term follow-up data of the clinical course of seronegative rheumatoid arthritis are sparse. Here we describe four cases with a rare disease entity of aggressive destructive seronegative (rheumatoid) arthritis with 20-35 years of follow-up.
  
  
  
  The four cases are women with an initial presentation of seronegative rheumatoid arthritis in 1980-1996 and have received disease-modifying anti-rheumatic drugs since the diagnosis. In all cases, the condition has been refractory to treatments and evolved into a severe disease with destructions of the wrists, sub-talar and ankle joints, as well as large joints but not small joints of fingers and toes. All cases are negative with regard to rheumatoid factor, anti-cyclic citrullinated peptide antibodies and antibodies against carbamylated proteins.
  
  
  
  This report adds to the existing literature, making the reader aware of this sub-type of inflammatory arthritis which despite being seronegative, can have devastating disease consequences. The report highlights the need for further research into this field in order to better understand this disease sub-type, the pathogenesis, disease course and outcomes.
authors.affiliation: Rheumatology/Medicine, Jyväskylä Central Hospital, Keskussairaalantie 19, FI-40620, Jyväskylä, Finland.
authors.forename: Elena
authors.initials: E
authors.lastname: Nikiphorou
authors.affiliation: Rheumatology/AIR, Department of Clinical and Experimental Medicine, Linköping University, SE-581 85, Linköping, Sweden.
authors.forename: Christopher
authors.initials: C
authors.lastname: Sjöwall
authors.affiliation: Rheumatology/Medicine, Jyväskylä Central Hospital, Keskussairaalantie 19, FI-40620, Jyväskylä, Finland.
authors.forename: Pekka
authors.initials: P
authors.lastname: Hannonen
authors.affiliation: Rheumatology/Medicine, Jyväskylä Central Hospital, Keskussairaalantie 19, FI-40620, Jyväskylä, Finland.
authors.forename: Tuomas
authors.initials: T
authors.lastname: Rannio
authors.affiliation: Rheumatology/Medicine, Jyväskylä Central Hospital, Keskussairaalantie 19, FI-40620, Jyväskylä, Finland. tuulikki.sokka-isler@ksshp.fi.|Faculty of Health Sciences, University of Eastern Finland, Jyväskylä Central Hospital, Keskussairaalantie 19, 40620, Jyväskylä, Finland. tuulikki.sokka-isler@ksshp.fi.
authors.forename: Tuulikki
authors.initials: T
authors.lastname: Sokka
mesh_terms: D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000000981:diagnostic imaging / Q000628:therapy*; D018450:Disease Progression; D005260:Female; D006801:Humans; D008875:Middle Aged; D011859:Radiography
keywords: Erosions; Outcomes; Rheumatoid arthritis; Seronegative