Rheumatoid factor
You don't need to be Editor-In-Chief to add or edit content to WikiDoc. You can begin to add to or edit text on this WikiDoc page by clicking on the edit button at the top of this page. Next enter or edit the information that you would like to appear here. Once you are done editing, scroll down and click the Save page button at the bottom of the page.
|
WikiDoc Resources for Rheumatoid factor | |
|
Articles | |
|---|---|
|
Most recent articles on Rheumatoid factor Most cited articles on Rheumatoid factor | |
|
Media | |
|
Powerpoint slides on Rheumatoid factor | |
|
Evidence Based Medicine | |
|
Cochrane Collaboration on Rheumatoid factor | |
|
Clinical Trials | |
|
Ongoing Trials on Rheumatoid factor at Clinical Trials.gov Trial results on Rheumatoid factor Clinical Trials on Rheumatoid factor at Google
| |
|
Guidelines / Policies / Govt | |
|
US National Guidelines Clearinghouse on Rheumatoid factor NICE Guidance on Rheumatoid factor
| |
|
Books | |
|
News | |
|
Commentary | |
|
Definitions | |
|
Patient Resources / Community | |
|
Patient resources on Rheumatoid factor Discussion groups on Rheumatoid factor Patient Handouts on Rheumatoid factor Directions to Hospitals Treating Rheumatoid factor Risk calculators and risk factors for Rheumatoid factor
| |
|
Healthcare Provider Resources | |
|
Causes & Risk Factors for Rheumatoid factor | |
|
Continuing Medical Education (CME) | |
|
International | |
|
| |
|
Businness | |
|
Experimental / Informatics | |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Phone:617-525-6884
Please Take Over This Page and Apply to be Editor-In-Chief for this topic: There can be one or more than one Editor-In-Chief. You may also apply to be an Associate Editor-In-Chief of one of the subtopics below. Please mail us [2] to indicate your interest in serving either as an Editor-In-Chief of the entire topic or as an Associate Editor-In-Chief for a subtopic. Please be sure to attach your CV and or biographical sketch.
Rheumatoid factor (RF or RhF) is a blood test performed in patients with suspected rheumatoid arthritis (RA).
It is an antibody against the Fc portion of IgG, which is itself an antibody, IgM or IgA type; RF and IgG form immune complexes, which are part of the disease process of various rheumatological diseases. Rheumatoid factor can be either Type 2 (monoclonal IgM to polyclonal IgG) or 3 (polyclonal IgM to polyclonal IgG) cryoglobulin.
These factors are antibodies in the serum of people who suffer from rheumatoid arthritis. Antigenic determinants or immunoglobins.
| Reference Range |
| <30 IU/ml |
- Positive in persons with symptoms
Indications
RF is often determined in patients suspected in any form of arthritis. It has relatively little use there, as positive results can be due to other causes, and negative results do not rule out disease. But, in combination with signs and symptoms, it can be diagnostic and prognostic. It is part of the disease criteria of RA.
Interpretation
High levels RF (generally above 20 IU/mL, 1:40 or over the 95th percentile there is some variation among labs) are indicative of rheumatoid arthritis (present in 80%) and Sjögren's syndrome [1] (present in almost 100%) [2].
The higher the levels of RF the higher the possibility of a more destructive articular disease.
There is a high rate of false positives due to other causes. These are:
Differential Diagnosis
- Anthracosis
- Any chronic viral infection
- Asbestos
- Asthma
- Bacterial endocarditis
- Behcet's Syndrome
- Bronchitis
- Chronic hepatitis
- Cirrhosis
- Cryoglobulinemia
- Dermatomyositis
- Hepatitis
- Juvenile Rheumatoid Arthritis
- Leukemia
- Mixed connective tissue disease
- Infectious mononucleosis
- Myocardial Infarction
- Neoplasm
- Osteomyelitis
- Polymyositis
- Sarcoidosis
- Sclederoma
- Sjogren's Syndrome
- Syphillis
- Systemic Lupus Erythmatosus (SLE)
- Tuberculosis
External links
- MedlinePlus page on RF
- Labtestsonline page on RF
- Gawlitza G, Wigand R (1976). "[A comparison of two tests for rheumatoid factor: latex test and l-agglutination (author's transl)]". Immun Infekt 4 (1): 23-8. PMID 1254316.
References
Acknowledgement and Attribution Regarding Sources of Content
Some of the initial content on this page may be incorporated in part from copyleft sources in the public domain including wikis such as Wikipedia and AskDrWiki. Drug information for patients came from the The National Library of Medicine. Infectious disease information may have come from the Centers for Disease Control (CDC). Differential Diagnoses are drawn from clinicians as well as an amalgamation of 3 sources: 1.The Disease Database; 2. Kahan, Scott, Smith, Ellen G. In A Page: Signs and Symptoms. Malden, Massachusetts: Blackwell Publishing, 2004:3; 3. Sailer, Christian, Wasner, Susanne. Differential Diagnosis Pocket. Hermosa Beach, CA: Borm Bruckmeir Publishing LLC, 2002:7 .
