Can FTA-ABS be false negative?
Can FTA-ABS be false negative?
The fluorescent treponemal antibody that measures IgM antitreponemal antibodies, the IgM-FTA-ABS test, has been associated with false-positive and false-negative results.
What does a negative FTA-ABS mean?
FTA-ABS detects the majority but not all cases of the disease. It is thus a way of screening for the disease. A negative FTA-ABS test result is consistent with a person not having syphilis. However, a person may have a negative FTA-ABS test result while in the early (primary) and late (tertiary) stages of the disease.
What would cause a false-positive RPR?
The RPR test also can produce false-positive results, suggesting you have syphilis when you actually don’t. One reason for a false positive is the presence of another disease that produces antibodies similar to the ones produced during a syphilis infection.
When does FTA-ABS turn positive?
An abnormal or positive result usually means you have an active syphilis infection or have had one before. Your FTA-ABS test result will be positive for the rest of your life, even after you’ve been treated. There are two other skin conditions called yaws and pinta that may cause a positive FTA-ABS test result.
What does positive FTA-ABS mean?
A positive FTA-ABS is often a sign of a syphilis infection. This test result will remain positive for life even if syphilis has been adequately treated. Therefore, it cannot be used to monitor the treatment of syphilis or determine that you have active syphilis.
Why does FTA-ABS stay positive?
Does FTA-ABS stay positive after treatment?
An abnormal or positive result usually means you have an active syphilis infection or have had one before. Your FTA-ABS test result will be positive for the rest of your life, even after you’ve been treated.
How long does RPR stay positive?
With blood testing, syphilis can be detected as early as 1 to 2 weeks after exposure. The highest accuracy can be expected within about three months, with false positive results possible any time within the initial 90 days after infection.
Does RPR always remain positive?
The syphilis antibody test is confirmed as positive with the FTA-ABS. Both of these tests remain positive for years and do not decline with therapy. The RPR is positive. The most likely explanation for this combination is active syphilis.
What can cause a false positive RPR test?
Other infections can influence the results of an RPR test if they cause the body to produce similar antibodies to syphilis. Some potential infections that could cause a false positive include: When a person’s test results come back as positive, meaning they may have syphilis, their doctor will likely run further tests.
What is the advantage of VDRL over RPR?
One major advantage that VDRL has over RPR is that VDRL can use Cerebrospinal Fluid (CSF) as a specimen for the test. This gives VDRL an edge over RPR when it comes to the use of CSF as a specimen.
