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Similarities and differences between RA and JRA/JIA |
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| Feature |
RA |
JRA/JIA |
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|
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| Classification criteria |
Single disease with different manifestations |
Phenotypically and genetically distinct subtypes |
| Gender |
Females > males |
Females > males except in systemic arthritis |
| Age of onset |
Puberty plus; peak 4th to 5th decade |
Polyarticular: throughout childhood; peak 1-3 years of age |
| Pauciarticular: early childhood; peak 1-2 years of age |
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| Systemic: throughout childhood; no peak |
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| Extended multiplex families |
Present |
Very rare |
| Family history of other autoimmune disorders |
Present |
Present |
| Typical ocular involvement |
Keratoconjunctivitis sicca |
Chronic anterior uveitis |
| Prevalence |
10/1000 |
0.86/1000 |
| Ethnic distribution |
Reported in all populations |
EOPA is rare in non-Caucasians |
| HLA association |
HLA DRB1*0401, 0404, 0101 in Caucasians |
EOPA: HLA-A2, -DR5, -DR8, -DPB1*0201. (HLA-DR4 is protective) |
| Late pauciarticular: HLA-B27 |
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| Polyarticular: HLA-DR1, -DR4 |
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| Shared epitope |
Defined; amino acid positions 67-74 of third hypervariable region |
Not described |
| Growth/developmental issues |
Rare |
Common |
| Pathophysiology |
Th1-mediated disease |
Th1-mediated disease (Pauciarticular: Also Th2-mediated) |
| Autoantibodies |
IgM RF common |
IgM RF rare |
| Natural history |
Majority have long-term disability |
Fewer than half have long-term disability |
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EOPA, early-onset pauciarticular arthritis; HLA, human leukocyte antigen; JIA, juvenile idiopathic arthritis; JRA, juvenile rheumatoid arthritis; RA, rheumatoid arthritis; RF, rheumatoid factor; Th, T helper. | ||
Prahalad and Glass Arthritis Res 2002 4(Suppl 3):303 doi:10.1186/ar594 |
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