Venereal Disease Research Laboratory test
Venereal Disease Research Laboratory test | |
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Purpose | blood test for syphilis |
The Venereal Disease Research Laboratory test (VDRL) is a blood test for
History
The VDRL type test was invented before
Mechanism
The VDRL is a
The rapid plasma reagin (RPR) test uses the same antigen as the VDRL, but in that test, it has been bound to several other molecules, including a carbon particle to allow visualization of the flocculation reaction without the need of a microscope. Many other medical conditions can produce false positive results, including some viruses (mononucleosis, hepatitis), drugs, pregnancy, rheumatic fever, rheumatoid arthritis, lupus, and leprosy.[citation needed]
The syphilis anti-cardiolipin antibodies are beta-2 glycoprotein independent,[2] whereas those that occur in antiphospholipid syndrome (associated to lupus for example) are beta-2 glycoprotein dependent, and this can be used to tell them apart in an ELISA assay.[3] This test is very useful as the trend of titres are correlated to disease activity (i.e. falling titres indicate successful treatment). It has a very good sensitivity for syphilis, except in late tertiary form.[citation needed]
Other tests
There are a number of treponemal-specific tests such as the fluorescent treponemal antibody-absorption (
The MHA-TP is used to confirm a syphilis infection after another method tests positive for the syphilis bacteria. The MHA-TP test detects antibodies to the bacteria that cause syphilis and can be used to detect syphilis in all stages, except during the first 3 to 4 weeks. This test is not done on spinal fluid. The MHA-TP test is rarely used any more.