What Is The Testing Window Period For VDRL And TPHA?

Posted on Wed, 19 Mar 2014

Medically reviewed by Ask A Doctor - 24x7 Medical Review Team

Wed, 19 Mar 2014 Answered on

Tue, 8 Apr 2014 Last reviewed on

Question : HI I had tested for VDRL at 8 week after the exposure and TPHA at 10 week both came out negative.Are these test conclusive.my exposure was unprotected oral sex on a sex worker 3 months back.I also tested for HIV Rapid at 13 week which is alslo negative.I am sexually active person had unprotected oral sex many times before but had always protected vaginal sex.Please suggest are these test conclusive to rule out syphilis and Hiv.I have symptoms like oral thrush and some ulcer like formation in my mouth which went away in a week.Thanks

Answered by Dr. Dr. Kakkar (39 minutes later)

Brief Answer: You seem to be safe Detailed Answer: Hello and welcome to healthcaremagic. I am Dr. Kakkar. I have gone through your concern and I have understood it. VDRL and TPHA have a window period of 3-12 weeks (window period is the period after infection when it can be detected in a test). TPHA in general, becomes positive before VDRL. Since you got tested for VDRL at 8 weeks and TPHA at 10 weeks, therefore as far as syphilis is concerned I would advice that you get a repeat test for both VDRL and TPHA at 12 weeks to be absolutely sure (though the chances are less likely for these tests to come out as positive as the window period has a range of 3-12 weeks and you have covered it almost 2/3rd of it) HIV rapid test negative at 13 weeks, certainly rules out HIV as it covers the window period of HIV which is 1-3 months (provided you did nt had any sexual contact in between). You seems to be safe. Always practice safe sex with a condom. I hope this answers you query. regards

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar

Follow up: Dr. Dr. Kakkar (6 minutes later)

Hi Thanks a lot for your comments.But I am worried about my symptoms.I want to know whether these tests would have been positive because of my earlier exposure as well?As i mention I had unprotected cunnilings many time before.TPHA and VDRL would have been positive now irrespective of any stages of Syphilis right?

Answered by Dr. Dr. Kakkar (11 minutes later)

Brief Answer: You seem to be safe. Detailed Answer: Hi. Yes. You got it right. If your tests come -ve at 3 months after a risky sexual contact, it rules out both syphilis and HIV. That means if your past sexual exposures were 3 months prior to the tests, that means you could not have got infected from your earlier exposures. However always practice safe sex with a condom. regards

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar

Follow up: Dr. Dr. Kakkar (1 minute later)

but what about my symptoms oral thrush for last one month,alopecia aerata and have rashes on my penis even before this recent exposure?Sorry for asking again and again i am bit worried.Does low vitamin D caused skin allergies?Thanks in advance.

Answered by Dr. Dr. Kakkar (13 minutes later)

Brief Answer: Thrush could be a side effect of antibiotics Detailed Answer: Hi. Oral thrush could be a side effect of oral antibiotics (your drug history mentions Azelupin 500mg). You could also be simultaneouly having candidal balanitis be cause of the very same reason(Antibiotics!!). Use a topical antifungal cream e.g clotrimazole for 7 days, for penile rashes Get a blood sugar tested test too. Alopecia areata is unrelated to STDs. It is not a sign of STDs I hope this answers your query regards

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar