Clinical and biological polymorphism of rheumatoid arthritis

Rheumatoid arthritis (RA) is a frequent disease, leading in more than 50% of cases to severe disability within 5 years of evolution, and sometimes to the premature death of the patient. It is therefore of crucial importance to diagnose, evaluate, and treat this crippling disease as soon as possible. We need accurate clinical, biological, immunological and radiographic parameters which will permit both early diagnosis and evaluation of the patient's prognosis. However, RA is a very heterogeneous disease which is sometimes considered as a clinical syndrome. The clinical heterogeneity of RA is well known; some cases are very mild and self-limiting, while others are seriously progressive and include extra-articular manifestations which can be life-threatening. There is also a biological and immunological heterogeneity of RA, depending on the presence or absence of: rheumatoid factor, high levels of serum IgA, and antinuclear, anti-Ro, antiperinuclear, or anti-stratum corneum antibodies. The association between HLA DR antigens and the severity of RA has been demonstrated in recent studies including some by our group. HLA DRB1*0401 or 0404 homozygous, or HLA DRB1*0401/0404/0408 heterozygous, or HLA DRB1*04 + HLA DRB1*0101 are associated with severe and erosive RA. Extra-articular manifestations such as nodules, vasculitis or Felty syndrome are very often observed in patients homozygous for HLA DRB1*0401 or 0404. The presence of HLA DR4 seems to be correlated with the articular erosions and not with rheumatoid factor. There is a clear need for a 'staging' of RA in order to define more homogeneous clusters of patients.(ABSTRACT TRUNCATED AT 250 WORDS)