Aa
How conclusive are my results?
I am male and had unprotected vaginal sex with Thailand csw. I tested with labcorp using HIV DNA PCR (162100) 12 days after exposure and result was negative. I tested using oraquick antibody test 27 days after exposure and result is negative.
Do I need further testing? My concern is CRF AE exposure and risk that lab corps DNA PCR HIV is not sensitive to this subtype. Also, do you know if labcorps 162100 is the Roche Amplicor test?
Many thanks.
Do I need further testing? My concern is CRF AE exposure and risk that lab corps DNA PCR HIV is not sensitive to this subtype. Also, do you know if labcorps 162100 is the Roche Amplicor test?
Many thanks.
MEDICAL PROFESSIONAL
I can't tell you the copy numbers at particular intervals, but I believe you are correct. In any case, I do know that the HIV PCR is always positive within 12 days of catching HIV. You don't have it. Time to move on. I won't have any further comments or advice.
Thank you Doctor. I called Labcorps and found out that they use the Roche Taqman assay which according to the FDA is sensitive to all HIV-1 subtypes including E - just as you said!
Furthermore - this DNA PCR assay can detect as low as 10 copies per ml - which makes me feel a lot better because I can't imagine that after 12 days post potential exposure - that if infected - I would have Les than 50 copie per ml (which according to the FDA - the Roche Taqman assay was able to detect 100%).
I guess my last question to you (and thanks so much for your guidance) is that after 12 days - if infected in a healthy adult - there would be more than 50 copies per ml - more like thousands right?
Many thanks.
Furthermore - this DNA PCR assay can detect as low as 10 copies per ml - which makes me feel a lot better because I can't imagine that after 12 days post potential exposure - that if infected - I would have Les than 50 copie per ml (which according to the FDA - the Roche Taqman assay was able to detect 100%).
I guess my last question to you (and thanks so much for your guidance) is that after 12 days - if infected in a healthy adult - there would be more than 50 copies per ml - more like thousands right?
Many thanks.
MEDICAL PROFESSIONAL
This is one of those urban myth kinds of worries. All subtypes are detected by the PCR test, and in the US the frequency of those missed by the antibody tests is too low to measure. Look at it this way: In over 10 years there has never been a transfusion-related HIV infection in the US, because the standard tests simply never miss HIV.
Thanks and yes - it was the dumbest and most reckless thing I've ever done.
A follow up question I have is with regard to your comment on antibodies and their difficulites with some subtypes - do you think a final test with Oraquick at 6 weeks will be conclusive?
A follow up question I have is with regard to your comment on antibodies and their difficulites with some subtypes - do you think a final test with Oraquick at 6 weeks will be conclusive?
MEDICAL PROFESSIONAL
Welcome to the forum. If you don't mind, I'll start out with some common sense advice -- which you may be telling yourself: please start planning on 100% condom use for exposures with CSWs, especially in HIV endemic areas. With a condom, there would be no need for concern or for testing.
The DNA PCR tests are sensitive for any and all types of HIV-1. They can have a problem with HIV-2, but that's not the issue here -- and of course HIV-2 infections are rare outside the areas of African where they originated. My understanding is that HIV testing concerns for some HIV subtypes are relevant only for antibody tests. I do not know what assay Labcorp uses, but I suspect you could easily find out by searching their website or contacting them directly.
In any case, the combination of negative PCR at 12 days and negative antibody at 27 days is probably 100% reliable. However, official resources still suggest later testing, e.g. an HIV antibody/p24 antigen duo test at 4 or more weeks after exposure, or a stand-alone antibody test at 6 weeks. If I were in your situation, I would not feel a need for any further testing, but feel free if you remain nervous about it.
Regards-- HHH, MD
The DNA PCR tests are sensitive for any and all types of HIV-1. They can have a problem with HIV-2, but that's not the issue here -- and of course HIV-2 infections are rare outside the areas of African where they originated. My understanding is that HIV testing concerns for some HIV subtypes are relevant only for antibody tests. I do not know what assay Labcorp uses, but I suspect you could easily find out by searching their website or contacting them directly.
In any case, the combination of negative PCR at 12 days and negative antibody at 27 days is probably 100% reliable. However, official resources still suggest later testing, e.g. an HIV antibody/p24 antigen duo test at 4 or more weeks after exposure, or a stand-alone antibody test at 6 weeks. If I were in your situation, I would not feel a need for any further testing, but feel free if you remain nervous about it.
Regards-- HHH, MD
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