Systemic lupus erythematosus and rheumatoid arthritis

 
 
6. Rheumatoid arthritis 
The classical symptoms of rheumatoid arthritis (RA) include swollen and 
painful joints, often in a symmetrical fashion in the joints of the hands, wrists 
and feet, morning stiffness lasting hours, fatigue, and occasionally moderate 
fever. RA (MIM no. 180300) affects approximately 0.5-1.0 % of the population 
of western Europe and north America.
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The disease is prevalent throughout the 
world but the highest frequencies of RA are found among Native American-
Indians with reported frequencies as high as 6.8%.
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The aetiology of RA is still 
unclear and it is considered to be a multifactorial disease with interacting 
contributions from genetic, infectious, environmental and hormonal factors.
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The diagnosis of RA is based on the American College of Rheumatology (ACR) 
1987 criteria for the classification of RA (Table 2).
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