Which of the following best represents the impoance of Rheumatoid factor in rheumatoid ahritis?
Rheumatoid factor (RF) consists of heterogeneous autoantibodies of the IgM class that react against the Fc region of human IgG. It is found in 70% of rheumatoid ahritis patients and is associated with a worse prognosis, since higher levels of rheumatoid factor are associated with more aggressive disease, rheumatoid nodules and extra aicular manifestations. Ref: Elective Hand Surgery: Rheumatological and Degenerative Conditions, Nerve Compression Syndromes By Michel Merle, Page 97 ; Measuring Immunity: Basic biology and Clinical Assessment By Michael T. Lotz, Page 189
Rheumatoid factor is associated with bad prognosis
Rheumatoid factor correlates with disease activity
Rheumatoid factor is very common in childhood Rheumatoid ahritis
Absent rheumatoid factor rules out the diagnosis of Rheumatoid ahritis