HealthCareMagic is now Ask A Doctor - 24x7 | https://www.askadoctor24x7.com

question-icon

Experiencing Fever, Nausea And Oral Ulcers. How Accurate Is An HIV PCR DNA After 14 Days?

default
Posted on Wed, 17 Jul 2013
Question: How accurate is an HIV PCR DNA (not RNA but DNA) test after 14 days. I was negative after 14 days possible exposure but now at 3 weeks I am experiencing fever, nausea, oral ulcers and am highly concerned. I realize I could get additional follow up testing with an ELISA test in the future or take a new PCR DNA test now to help confirm the result and I will be happy to do those things but right now I want to know how accurate it was likely to have been at the 2 week XXXXXXX because quite honestly I am extremely stressed out and worried about the whole thing at this moment. Thank you.
doctor
Answered by Dr. Binod Kumar Pati (2 hours later)
Hi,

Thanks for your querry to XXXXXXX

Blood samples are processed to detect HIV proviral DNA in peripheral blood lymphocytes by real time pcr.
HIV DNA PCR can detect as low as 10 copies of proviral DNA per ml of blood.
There is definitely association of some false positives with it. But very less false negative, particularly if test is done after 2 weeks. Hence possibilities that you may HIV is less likely.

All your current symptoms can be explained by a viral inifection and stress.

How ever, if the exposure is really a high risk one and you more anxious, you can go for a repeat test at 4th and 6th week, but hardly it will give you extra benefit.
Go for HIV antibody detection by ELISA after 6 - 8 weeks.


Hope things are more clear now.
God bless you.
Above answer was peer-reviewed by : Dr. Prasad
doctor
default
Follow up: Dr. Binod Kumar Pati (1 hour later)
Hi,

Thank you for your response.

you wrote "How ever, if the exposure is really a high risk one and you more anxious, you can go for a repeat test at 4th and 6th week, but hardly it will give you extra benefit."

Do you mean that a repeat test of the dna pcr at 4 and 6 weeks will not give me much benefit because it is NOT more reliable at 4 weeks than it is at 2 weeks? Is it not any more reliable at 4 weeks? Or is it that it is only slightly more reliable? Can you give me an estimate of how certain the test is after the 14 days that I took it? I don't expect an exact percentage necessarily if you dont have it but can you give me a near estimate? For example is it about 90% accurate after 14 days? is it closer to 80? 70? higher? lower? If you can give me an estimate of the accuracy after 14 days it might help me calm down by knowing how strong an indicator it is of my status. Thank you.
doctor
Answered by Dr. Binod Kumar Pati (11 hours later)
HI
Welcome once again.

DNA PCR tests can detect pro-viral DNA at a frequency of one copy per 10,000–100,000 blood mononuclear cells. Thus, these tests are extremely sensitive. As a consequence of the high degree of sensitivity, there occurs some loss of specificity, and false-positive results have been reported with each of these techniques.

For this reason, a positive ELISA with a confirmatory Western blot remains the "gold standard" for a diagnosis of HIV infection.

The reason why I had written that statement is based on personal experience.
Once the test was negative at 2 weeks, it usually remained the same even if done at 4th or 6th weeks, in all my cases.

I hope it is clear. I expect the same in your case as well.
However, my advice is to go with guidelines and go for ELISA followed by western blot 6-8 weeks post exposure.

Thanks once again for your query. You may close the discussion and rate it if no more to solve.

Have a nice day.




Note: Get personalized answers to your HIV related queries You can choose to talk face to face with your doctor. Book a Video Call now.

Above answer was peer-reviewed by : Dr. Vaishalee Punj
doctor
Answered by
Dr.
Dr. Binod Kumar Pati

Infectious Diseases Specialist

Practicing since :2000

Answered : 180 Questions

premium_optimized

The User accepted the expert's answer

Share on

Get personalised answers from verified doctor in minutes across 80+ specialties

159 Doctors Online

By proceeding, I accept the Terms and Conditions

HCM Blog Instant Access to Doctors
HCM Blog Questions Answered
HCM Blog Satisfaction
Experiencing Fever, Nausea And Oral Ulcers. How Accurate Is An HIV PCR DNA After 14 Days?

Hi,

Thanks for your querry to XXXXXXX

Blood samples are processed to detect HIV proviral DNA in peripheral blood lymphocytes by real time pcr.
HIV DNA PCR can detect as low as 10 copies of proviral DNA per ml of blood.
There is definitely association of some false positives with it. But very less false negative, particularly if test is done after 2 weeks. Hence possibilities that you may HIV is less likely.

All your current symptoms can be explained by a viral inifection and stress.

How ever, if the exposure is really a high risk one and you more anxious, you can go for a repeat test at 4th and 6th week, but hardly it will give you extra benefit.
Go for HIV antibody detection by ELISA after 6 - 8 weeks.


Hope things are more clear now.
God bless you.