Difference between TPHA and VDRL in syphilis

Difference between TPHA and VDRL in syphilis

The main difference between TPHA and VDRL is that TPHA is a confirmatory test for syphilis, while VDRL is mainly used as a screening test and for monitoring treatment response, as said by Dr. Kamal Raj Dhital, top dermatologist and std specialist in Nepal with over 10 years of experience.

TPHA detects antibodies specifically against Treponema pallidum and may remain positive for many years, even after successful treatment. VDRL detects non-treponemal antibodies, and its titre generally decreases after effective treatment. Therefore, VDRL is useful for assessing disease activity and response to therapy, whereas TPHA helps confirm exposure to syphilis. Both tests should be interpreted together with symptoms, examination and clinical history, as mentioned by Dr. Kamal Raj Dhital, Dermatologist and  STD specialist in Nepal.