The VDRL test stands for venereal disease research laboratory, which is a test used to determine whether you have syphilis, which is a sexually transmitted infection (STI). The bacteria Treponema pallidum causes syphilis. The bacteria infects by invading the mouth or vaginal region lining.
The VDRL test measures the substances (proteins), called antibodies, that your body can make if you have come in contact with the bacteria responsible for syphilis. The test looks for antibodies made by your body in response to antigens released by bacteria-damaged cells. Antibodies are proteins that your immune system produces to fight against germs or some infections. Testing for these antibodies can help doctors determine if you have syphilis.
This test is accurate even if you do not have syphilis symptoms. The VDRL test can be done regardless of whether you are presently experiencing symptoms or not; since it looks for antibodies created due to a syphilis infection.
Why do doctors do VDRL tests?
If your doctor suspects you have syphilis, he or she will most likely request a VDRL test. The following early signs may trigger your doctor to order this test:
- One tiny, painless sore
- Swelling in lymph nodes surrounding the sore
- Skin rash
In some circumstances, your doctor may do a syphilis screening even if you have no symptoms of the illness. If you're pregnant, your doctor will check for syphilis as part of your routine treatment. This is a common process, and it does not imply that your doctor suspects you of having syphilis.
If you're being treated for another STI, such as gonorrhea, or HIV, your doctor may additionally test you for syphilis.
The VDRL test
For the VDRL test, a healthcare expert will collect a sample of blood. Normally, blood is extracted from a vein in the elbow's crease or the hand's back. This blood sample will then be submitted to a laboratory to be tested for syphilis-related antibodies. If your doctor feels that your syphilis infection has progressed to your brain, he or she may prescribe additional tests to examine your spinal fluid as well as your blood.
The person taking the VDRL test does not need to fast or stop taking any medicines. If your doctor wants you to refrain you from certain foods or medication, then they will notify you prior to the test.
Understanding your VDRL test findings
If your test for syphilis antibodies comes negative, it means you don't have the disease.
If your test for syphilis antibodies comes positive, you most likely have the disease. If this happens, your doctor will schedule an additional test to confirm the results. A treponemal test is frequently used to confirm a positive test result. Treponemal tests determine if your immune system has developed particular antibodies in response to the syphilis-causing organism Treponema pallidum.
Possibility of false positives and negatives
The VDRL test is not always reliable. For example, if you've had syphilis for less than three months, your body may provide false-negative results since it takes this long to produce antibodies. In late-stage syphilis, the test is also unreliable.
The following can result in false-positive results:
- Lyme disease
- HIV
- Use of IV drugs
- Malaria
- Pneumonia
- Systemic lupus erythematosus
- Tuberculosis
Even if you have syphilis, your body may not develop antibodies in some circumstances. As a result, the VDRL test will be inaccurate.
The antibodies produced by a syphilis infection might remain in your body long after the illness has been cured. This means you could always get positive results on this test.
The risks of taking the VDRL test
There are no such major risks related to the VDRL test. One may experience small difficulties, such as moderate discomfort during the blood draw or little bruising or bleeding afterward.
Long-term Outlook
Syphilis is curable, but it's critical to see a doctor as soon as you suspect you've been exposed. If left untreated, it can spread throughout your body and cause organ damage. The VDRL test isn't perfect, but it's a reliable test that can assist in detecting if you've been infected. The most important fact to remember is to practice safe intercourse, and if you suspect you've had contact with syphilis, visit your doctor immediately.