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Had unprotected sex. Can I go for pcr test to find out infection?

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Practicing since : 2006
Answered : 2015 Questions
i had unprotected sex 20 days ago , can p24 and pcr test be applied now to know if i am infected or no ? and is the accuracy is realible ??
Posted Tue, 26 Feb 2013 in Skin Hair and Nails
Answered by Dr. Kalpana Pathak 1 hour later
One can undergo P24 antigen test or PCR for viral load to know about HIV infection with in the window period of infection when no symptoms, signs or antibodies have formed in the blood to detect HIV. These are reliable and the only tests available to detect early HIV infection. So i would advise you to undergo these tests if the partner had HIV or if there are any doubts. However possibilities of inaccuracy even if almost negligible is always there, hence even if the test is negative or positive, a second normal HIV antibody ELISA test is always advised for confirmation few weeks later.
Hope that answers your query.
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Follow-up: Had unprotected sex. Can I go for pcr test to find out infection? 16 minutes later
thank you for answering my question , i have some symptoms which emerged after 9 days of exposure , small lymph node swollen and i made sonar the doctor said its within normal range of any infction , i made cbc all ae perfect the lymph is within range and all other componantes in normal range .
could negative pcr test be false ? can negative p24 negative result be false too ? specially if after 21 days of potential exposure ??
Answered by Dr. Kalpana Pathak 34 minutes later
Thanks for writing back. Acute HIV infection may manifest as fever, malaise, night sweats, anorexia, sore throat, diarrhoea, persistent generalised enlarged lymph nodes( seen usually in groin, head and neck), joint pains etc.
Few isolated swollen lymph nodes could be due to any infection and usually a course of antibiotic settles them.
As far as blood tests are concerned, at such an early stage, in people with good immunity or when virus is latent no change or derangement in lymphocyte count might be seen. So it is not a confirmation that if its normal initially, there is no infection.

For earlier detection PCR test is most accurate with chances of being falsely negative remote. The results obtained are almost accurate but there is always a chance of lab error, human error or false positivity or negativity. Hence standard ELISA tests should be done later if required. PCR is more accurate than p24 and hence is used for early testing.
Should there be an iota of doubt it is better to go for testing.
Hope that answers your query.
Above answer was peer-reviewed by
Follow-up: Had unprotected sex. Can I go for pcr test to find out infection? 22 minutes later
thank you again , is a window of 20 days enough for pcr testing ? and is it enough for p24 testing as well ??
what kind of pcr test is better DNA or Rna ??

if both test come back negative after 20 days of possible exposure is it reccomneded to do another test after 3 months and stop having sex with my wife till that time ? or both test if came negative after (20 days of exposure) thats considered ok and have sex normally with my wife??

Answered by Dr. Kalpana Pathak 48 minutes later
You can undergo pcr test to know your status now. If you are undergoing PCR there is no need to get P24 assay done. PCR RNA should be done.
If the test comes negative, be assured you do not have infection. But still after three months get ELISA antibody test done. If PCR is negative, you can indulge in conjugal relations with spouse.
Hope that answers your query.
Above answer was peer-reviewed by
Follow-up: Had unprotected sex. Can I go for pcr test to find out infection? 17 hours later
dear dr kalpana , thanx for your answers , i have another one , one of the symptoms of HIV as you mentioned earlier is generalised swollen lymph nodes , do you mean it has to be in different places like XXXXXXX , armpit groin . or just multiple lymph swollen in same place is enough ?? i have in XXXXXXX only maybe 3 swollen but not seen only one of them is slightly seen .
Answered by Dr. Kalpana Pathak 28 minutes later
Firstly one should understand what is lymphadenopathy(LAP). It is enlargement of lymph nodes more than 1 cm.
So in your case firstly it should be seen whether you have LAP or not.
In acute HIV infection, persistent generalised LAP is present that is lymph nodes of more than 2 cm present at two or more non contiguous sites( sites far away from each other, not connected) for more than three months.
So frankly speaking you have nothing to worry. Your lymph nodes if swollen could be due to any infection of face , neck, scalp , ear or upper respiratory tract or these could be normal lymph nodes as well.
Hope that answers your query. Take care.
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Follow-up: Had unprotected sex. Can I go for pcr test to find out infection? 3 hours later
Dear Dr. Kaplana , i do appreciate yoyr assistance here is one more question :

i had unprotected sex 20 days ago ( twice in same day with same lady) vaginal sex ( inserted my penis in her vigina) . after 10 days i noticed swolled lymph in my right side XXXXXXX so i started to worry and surf the net . i got so paniced after that i felt dizzy then i had hemorrhage in my left eye . i made cbc and sonar ( attached the two results .after that i had one ulcer on my lip for 2 days now but it started to be dry now .are those signs that i have HIV +ve ?? today i made PCR test and P24 test hiv1 and hiv2 are those two test ok within 20 days of possible exposure ?please answer all my question as im so worried. and have a look to my test specially the lymph nodes plz
Answered by Dr. Kalpana Pathak 1 hour later
As I said your lymph nodes are too small to raise doubt if any.
As far as lip ulcer is concerned, it could be herpes simplex infection( viral infection) also known as cold sores. If you had no history of such lesions previously, you could have acquired it from the lady itself. Though the lesion does not cause any significant morbidity, it is recurrent and infectious. To treat the same, just apply an antibiotic cream now. Having a herpes infection does not point that one might be having HIV.
It's recurrence is usually seen during fever, winter months, stress or normally also and recurrence is preceded by itching or numbness or stinging sensation at the site of lesion. If any time you feel it is about to recur, you can use acyclovir cream five times in a day. However once the lesion forms, it is of no use.

As you had your doubts, it is good that you have got the tests done. The time is appropriate to get these tests done ie it is okay to get it done with in 20 days of exposure.

Lastly, I cannot find your attached reports on my dashboard. But as you had mentioned that your CBC was in normal range and as per the examining doctor your lymph nodes were in normal size range, so I do not feel there are any symptoms specifically pointing that you may acquired any STI specifically HIV from the patient.

Hope that answers all your doubts. Kindly do not panic, none of your symptoms are suggestive of any sexually transmitted infection. Just wait for the results of your tests.
Practice safe sexual practices and prefer not to indulge in extra marital sexual contacts.
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Follow-up: Had unprotected sex. Can I go for pcr test to find out infection? 19 hours later
Dear Dr. Kalpana ,

attached my reports the cbc and Lymph , what worries me is the lymph is it ok ??? i only have those swollen lymph in XXXXXXX area , all other parts are normal ( armpit , groin ...etc)

so are these considered to be hiv symptom because i have more than one swollen lymph in that area or it has to be in other places like armpit and groin as well .

please tell me your openion .

Answered by Dr. Kalpana Pathak 1 hour later
A single or few swollen lymph node does not in any way signifies HIV. I have already mentioned that HIV infection is characterised by persistent generalised lymphadenopathy that you are not having right now. Kindly do not worry much.

I would also like to point out that as you have multiple thyroid nodules with enlarged lymph nodes, these might be correlated. Kindly make it a point to take a surgeon's opinion for the same.


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