Syphilis Test VDRL

The syphilis test, VDRL is used to diagnose syphilis. The nontreponemal test is usually performed on blood but may be done on a serum sample or cerebro-spinal fluid (CSF). The test checks for an antibody that can be produced while infected with syphilis. Syphilis test VDRL is not very useful for detecting syphilis in very early or advanced stages. The test is also used to monitor patients' response to syphilis treatment. Syphilis VDRL test can result in false positive result even in the absence of infection due to recent immunization, other bacterial and viral infections and certain chronic conditions (e.g. liver disease, malignancy). Hence, a confirmatory test, the FTA-ABS test is done to check for syphilis-specific antibodies. Though no special preparation is required on the part of an individual who is to be tested, health care officials recommend abstaining from alcohol consumption 24 hours before a VDRL test.

Syphilis Test FTA-ABS

Treponema pallidum, the bacterium which causes syphilis has four subspecies:

• Treponema pallidum pallidum, which causes syphilis
  
• T. pallidum endemicum, which causes bejel or endemic syphilis
  
• T. pallidum carateum, which causes pinta
  
• T. pallidum pertenue, which causes yaws
  

To detect antibodies to Treponema pallidum, the FTA-ABS (Fluorescent treponemal antibody absorbed), a blood serum screening test is done. This is sometimes also referred to as syphilis Immunofluorescent Assay (IFA). The FTA-ABS test is a second test to confirm the presence of the infection and is usually done after the RPR test and VDRL test results are positive. FTA-ABS test is used to detect syphilis infection at any stage except during the first 3 to 4 weeks after exposure and in tertiary stages of the disease. The test is more reliable for the secondary stage of syphilis. The test is done on a sample of blood or spinal fluid. A positive FTA-ABS usually indicates infection with syphilis and a negative or nonreactive result means there is no current or past infection with syphilis. The test requires no prior preparation on the part of the individual who is to be tested.