Gram Negative Spiral
All of the following are true regarding VDRL test except:
|A||Positive in secondary syphilis|
|B||False positive reactions can occur|
|C||Titres decrease with treatment|
|D||The antigen is prepared from killed Treponema pallidum|
a. VDRL test is a non-treponemal test used for serodiagnosis of syphilis. The antigen used is cardiolipin antigen.
b. It is a slide flocculation test. Because antigen from treponemes is not used it gives false positive reaction certain conditions.
c. However, a true positive test indicates active infection as the titres decrease and become negative with successful treatment. .