Rheumatoid Factors: Clinical Applications

Table 1

Rheumatoid factor frequency in different diseases and conditions.

Disease	Frequency, %
Arthritis
Rheumatoid arthritis	70–90
Juvenile idiopahtic arthritis	5
Psoriatic arthritis	<15
Reactive arthritis	<5
Other connective tissue diseases
Primary Sjögren’s syndrome	75–95
Mixed connective tissue disease	50–60
Systemic lupus erythematosus	15–35
Systemic sclerosis	20–30
Dermato-/polymyositis	20
Systemic vasculitides (panarteritis; nodosa, Wegener’s granulomatosis)	5–20
Infectious diseases
Bacterial infections
Subacute bacterial endocarditis	40
Chlamydia pneumoniae infection
Klebsiella pneumoniae infection
Syphilis primary-tertiary	8–37
Tuberculosis	15
Viral infections
Coxsackie B virus infection	15
Dengue virus infection	10
EBV and CMV infections	20
Hepatitis A, B and C virus infection	25
HCV infection	40–76
Herpes virus infection	10–15
HIV infection	10–20
Measles	8–15
Parvovirus infection	10
Rubella	15
Parasitic
Chagas	15–25
Malaria	15–18
Onchocerciasis	10
Toxoplasmosis	10–12
Other diseases
Mixed cryoglobulinemia type II	100*
Liver cirrhosis	25
Primary biliary cirrhosis	45–70
Malignancy	5–25
After multiple immunisations	10–15
Chronic sarcoidosis	5–30
Healthy 50-year olds	5
Healthy 70-year olds	10–25

∗Monoclonal IgM rheumatoid factors; CMV: cytomegalovirus; EBV: Epstein-Barr virus; HCV: hepatitis C virus; HIV: human immunodeficiency virus. Adapted from [24, 25].