Navigation Links
Accurate interpretation of antinuclear antibodies test key to confirming autoimmune disease
Date:1/4/2011

The presence of antinuclear antibodies (ANA) indicates the possibility of autoimmunity and the indirect immunofluorescence (IIF) assay on HEp-2 cells is the standard blood test (ANA-HEp-2) used to detect ANA. However, studies have shown that a "false-positive" ANA test occurs in up to 13% of healthy individuals. In such cases the test detects the presence of autoantibodies that apparently are not associated with autoimmunity. Researchers from Brazil have now uncovered distinguishing characteristics of the ANA test in healthy individuals and patients with autoimmune disease, reducing the likelihood of an erroneous autoimmune disorder diagnosis. Their findings are published in the January 2011 issue of Arthritis & Rheumatism, a journal of the American College of Rheumatology (ACR).

The immune system is responsible for protecting the body against foreign invaders and infection, but in some individuals the immune system repeatedly attacks healthy cells in the body resulting in an autoimmune disease. According to the Centers for Disease Control and Prevention (CDC) autoimmune diseaseswhich include rheumatoid arthritis, Sjgren's syndrome, and systemic lupus erythematosusaffect up to 8% (22 million individuals) of the U.S. population.

The Brazilian research team, led by Luis Andrade, MD, PhD, from the Federal University of So Paulo, recruited 918 healthy individuals (634 females and 284 males) between the ages of 18 and 66 years for this study. In the control group were 153 patients with autoimmune rheumatic diseases that included lupus (87), systemic sclerosis (45), Sjgren's syndrome (11) and idiopathic inflammatory myopathy (10). To determine the concentration of ANA in the blood, ANA-HEp-2 tests were run on all participants and considered positive if a well defined IIF pattern was identified.

"The ANA-HEp-2 test is positive in a sizable portion of the general population and our findings established distinguishing characteristics between healthy individuals and patients with autoimmune disease which is essential to accurately interpret the test results," explained Dr. Andrade. Researchers determined that positive ANA-HEp-2 tests in healthy participants occurred predominantly as a nuclear fine speckled (NFS) pattern (at low to moderate titer) or as a nuclear dense fine speckled (NDFS) pattern (frequently at high titer) in 46% and 33% of ANA-positive healthy individuals, respectively. Healthy participants did not present a nuclear coarse speckled (NCS) or a nuclear homogeneous (Ho) pattern.

In those with autoimmune disease the ANA-HEp-2 showed positive results at a predominantly moderate to high titer. A distinct ANA-HEp-2 pattern profile was observed, characterized by the absence of the NDFS pattern and the exclusive occurrence of the NCS (26%), centromeric (8%), nuclear homogeneous (7%), and cytoplasmic dense fine speckled (3%) patterns. ANA-positive patients with confirmed autoimmune diseases also showed the presence of the NFS (42%), but at a higher titer than in healthy individuals.

At the end of a 4-year follow-up period 73% of the ANA-positive healthy individuals retained a positive test result, but did not develop any symptoms of autoimmune rheumatic disease. "Our study confirms that the ANA-HEp-2 pattern is critical in properly diagnosing autoimmune disorders and future research should attempt to reproduce the interpretation of test results among different ANA experts and ANA-HEp-2 slides brands," Dr. Andrade concluded.


'/>"/>

Contact: Dawn Peters
healthnews@wiley.com
781-388-8408
Wiley-Blackwell
Source:Eurekalert

Related medicine news :

1. Rapid Flu Test Most Accurate for Young Kids
2. LifeScan Recalls Specific Lots of Consumer and Professional OneTouch(R) SureStep(R) Test Strips Due To Inaccurate Readings at High Levels
3. Study: Mechanomyography to be accurate in detecting nerves during minimally invasive spine surgery
4. Whole body MRI is highly accurate in the early detection of breast cancer metastases
5. Innovative Technology Developed at AGH Accurately Monitors Healthcare Professionals' Handwashing Practices, Study Shows
6. Survey: Many Young Women Lack Accurate Information about STDs
7. Study finds cancer information on Wikipedia is accurate, but not very readable
8. New formula gives first accurate peak heart rate for women
9. Latino children with asthma less accurate in determining their lung function
10. Experimental TB Test Called Fast and Accurate
11. Blood test accurately predicts death from prostate cancer up to 25 years in advance
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/29/2017)... (PRWEB) , ... March 29, 2017 , ... AvePoint ... seventh North American office location in Richmond, Virginia, located at the Riverfront Plaza, 901 ... attended by Lieutenant Governor of Virginia Ralph S. Northam and Mayor of Richmond Levar ...
(Date:3/28/2017)... ... March 28, 2017 , ... A recent Bellwether ... teacher quality, the field must first improve teacher preparation program design. It then ... next” and that decades of input- and outcome-based research has failed to improve ...
(Date:3/28/2017)... ... March 28, 2017 , ... For many women, getting birth control isn’t as easy as it ... either don’t have access to a health care facility or a pharmacy within 60 minutes ... the United States or for many who are faced with health or personal issues that ...
(Date:3/28/2017)... ... March 28, 2017 , ... ... Ruel Williamson brings his extensive knowledge of appraisals, property values, ad valorem taxation, ... real estate valuation industry for more than 40 years. , “Ruel is a ...
(Date:3/28/2017)... ... March 28, 2017 , ... ... state legislatures and Congress to protect parental rights and civil liberties, and to ... in America. , The demonstration coincides with a press conference taking place Friday ...
Breaking Medicine News(10 mins):
(Date:3/28/2017)... The global emerging cancer diagnostics market is expected to ... 2023 and reach a figure of $6.34 billion by ... disease and is affecting a huge population. Many technologies ... is focused on emerging cancer diagnostics market specifically on ... to factors such as: increasing number of cancer cases, ...
(Date:3/28/2017)... LAS VEGAS , March 28, 2017  Las ... first surgeries with XEN45 Gel Stent (Allergan, ... built up in the eye, thereby reducing intraocular pressure ... 60 million people globally are affected by glaucoma that ... in vision loss and blindness, if left untreated. ...
(Date:3/28/2017)... , March 28, 2017 The ... (dupilumab) injection to treat adults with moderate-to-severe eczema ... eczema is not controlled adequately by topical therapies, ... advisable. Dupixent can be used with or without ... demonstrates our commitment to approving new and innovative ...
Breaking Medicine Technology: