Click here for an explanation of these scores
Answer Rating key
|
search
|
|
strong
|
|
appraisal
|
|
weak
|
|
confidence
|
|
moderate
|
Question answered:08/05/08
LabTestsOnline have an article on antinuclear antibodies [1], they report:
“The test is used to help diagnose systemic lupus erythematosus (SLE) and drug-induced lupus, but may also be positive in cases of scleroderma, Sjögren’s syndrome, Raynaud’s disease, juvenile chronic arthritis, rheumatoid arthritis, antiphospholipid antibody syndrome, autoimmune hepatitis, and many other autoimmune and non-autoimmune diseases. For this reason, SLE, which is commonly known as lupus, can be tricky to diagnose correctly. Because the ANA test result may be positive in a number of these other diseases, additional testing can help to establish a diagnosis of SLE. Your doctor may request other tests that are considered subsets of the general ANA test and that are used in conjunction with patient symptoms and clinical history to rule out a diagnosis of other autoimmune diseases.”
GP Notebook also report on ANA [2], stating:
“A raised antinuclear factor (ANF) is almost always present in SLE (80-90% - note that uraemia may render the result negative) (1).
Other conditions that are associated with a positive ANF but usually of lower titre than in SLE, include:
- systemic sclerosis (80%)
- Sjogren's syndrome (60%)
- polymyositis/dermatomyositis (30%)
- Still's disease (30%)
Also seen in:
- autoimmune chronic active hepatitis
- primary biliary cirrhosis
- infections, infective endocarditis
- fibrosing alveolitis
- drug reactions
Occasionally a positive ANF is found in normal elderly people.
Some patients are ANA positive but have antibodies which recognise different sets of nuclear proteins, termed extractable nuclear antigens (ENA)
- the commonest is anti-Ro which is usually clinically associated with photosensitivity (1)”
References
1) http://www.labtestsonline.org.uk/understanding/analytes/ana/test.html
2) http://www.gpnotebook.co.uk/simplepage.cfm?ID=-160759759
DISCLAIMER: TRIPanswers is a collection of clinical questions and answers. Each provider will have their own methodology in answering questions and these are likely not to be as rigorous as systematic review. If you have any doubt as to the implications of this contact the Q&A Service Provider for further information. This document is presented for information purposes only. This document cannot and should not be used as a basis of diagnosis or choice of treatment, and is in no way intended to replace professional medical care or attention by a qualified practitioner. TRIPanswers and TRIP Database Ltd are not responsible or liable for, directly or indirectly, ANY form of damage whatsoever resulting from the use/misuse of information contained in or implied by this document. Also, ensure you have read the terms and conditions for using the site.