Rheumatoid factor: Difference between revisions

Latest revision as of 10:39, 27 March 2022

General class of IgM antibodies to the Fc region of IgG
Most asymptomatic people with positive RF do not progress to rheumatoid arthritis
Neither specific nor sensitive for RA

Rheumatic disorders
- Rheumatoid arthritis (26-90%)
- Systemic lupus erythematosus (15-35%), Sjögren syndrome (75-95%), and mixed connective tissue disorder (50-60%)
- Type II and III cryoglobulinemia (40-100%)
- Polymyositis and dermatomyositis (5-10%)
Chronic infections
- Bacterial endocarditis (25-50%)
- Hepatitis B and hepatitis C (20-75%)
- Other viruses, such as HIV, Epstein-Barr virus, and CMV
- Some parasites, including malaria, schistosomiasis, and toxoplasmosis
Inflammatory disorders
- Cirrhosis (25%)
- Primary biliary cirrhosis (45-70%)
- Idiopathic pulmonary fibrosis (10-50%)
- Sarcoidosis (3-33%)
- Silicosis and asbestosis (30-50%)
Malignancies
- B-cell disorders (5-25%)
Normal aging
- ≥65 years of age (5-25%)

@@ Line 1: / Line 1: @@
 == Background ==
-* IgM antibody to the Fc region of IgG
+* General class of IgM antibodies to the Fc region of IgG
 *Most asymptomatic people with positive RF do ''not'' progress to [[rheumatoid arthritis]]
 *Neither specific nor sensitive for [[RA]]
@@ Line 9: / Line 9: @@
 * Rheumatic disorders
 ** [[Rheumatoid arthritis]] (26-90%)
-** [[Systemic lupus erythematosus]] (15-35%), [[Sjögren syndrome]] (75-95%), and [[mixed connective tissue disorder]] (50-60%)
+**[[Systemic lupus erythematosus]] (15-35%), [[Sjögren syndrome]] (75-95%), and [[mixed connective tissue disorder]] (50-60%)
 ** Type II and III [[cryoglobulinemia]] (40-100%)
 ** [[Polymyositis]] and [[dermatomyositis]] (5-10%)