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HIV Tests

I hope someone can clarify this for me. The screening test that I took 18 days post possible exposure says HIV Ag/Ab (Screening) and the method used is CMIA. However, the med tech said it's a 3rd generation test. Also, at the bottom of the results, there's a disclaimer that says that the results mean that the specimen does not have detectable HIV antibody. I'm confused because in my understanding, CMIA tests are 4th gen tests that tests BOTH atigens and antibodies. How come the med tech said it was a 3rd gen test and the results only refers to antibodies?

Just need clarification regarding this. Thanks!
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I understand that 4th gen CMIA tests are conclusive 28 days after possible exposure right? Will it make much difference if I took the test at 27 days? Also, I'm getting conflicting information from 2 doctors. One said that my test is already conclusive at 4 weeks but I can do it again after 6 weeks just to be sure, but the other said it's not conclusive until the 3rd month. Why do they have different recommendations? What is the likelihood of my 27-day test results changing on the 6th week? The CMIA 4th gen test looks for antigens AND antibodies correct? But based on the information that I've been reading, antigens peak in the blood 3-4 weeks after possible exposure and slowly disappears after that while antibodies are produced 4-6 weeks (or even later) after possible exposure. What if you get tested during the period when antigens are NO LONGER detectable in your blood but antibodies are NOT YET detectable? Wouldn't this produce a false non-reactive result?
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4 Comments
One day dosent really make a difference on your 27th day duo test.
The scenario you mentioned is not realistic,because when antigen are no longer detected in your blood it means the antibody has been formed and cleared the antigen already,in this case your test will still be positive because the antibody part is detected.
Thank you for your response! Is a 4th gen cmia test conclusive on the 27th day then? I ask because I've gone to 2 doctors and they gave different answers. One said it is conclusive but the other said any HIV test is not conclusive until the 3rd month.
its considered conclusive,when conclusive at 28th day with a DUO test,its very unlikely to changed again at 3 months,most health care recomended 3 months testing is abit conservative.
Also 3 month test is usually with the stand alone antibody test only.
Is a 4th gen CMIA the same as a DUO/Combo test? What would the results of a test like that look like? I got the results of my 4th gen CMIA test and it only shows a cut off value and a value indicator? Should the test have 2 values, one for antigens and one for antibodies?
3191940 tn?1447268717
COMMUNITY LEADER
The tech is incorrect.  Ab/Ag tests are 4th generation.  So either you were given an Ab test only, and it was 3rd generation, or the tech is wrong and you were given a 4th generation Ab/Ag.  Absolutely no way for anyone here to know which test was actually given.

In any case, no test is conclusive that soon.  Wait til the appropriate time so you'll know for sure.
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7 Comments
What is the appropriate time for conclusive 4th gen duo test??
For duo is it 4 weeks or 12 weeks??
4, all others are 12.
Is a 4th gen CMIA the same as a DUO/Combo test? What would the results of a test like that look like? I got the results of my 4th gen CMIA test and it only shows a cut off value and a value indicator? Should the test have 2 values, one for antigens and one for antibodies?
Yes it is the same. Why didn't you ask the lab about your results when they gave them to you?
I did. Unfortunately, I was given unclear answers. I was told that the test given to me was a 3rd Gen Elisa. But the lab results show that the method used was CMIA. (This test was taken at 18 days in a hospital.) At that time, I didn't know what the difference was between those two tests. It was only through reading online articles and forums that I realized that the 3rd Gen elisa is completely different from a CMIA. I called the lab to verify what test was given and the person just said it was a screening test. I tried to ask whether it was a test for both antigens and antibodies, and they just kept saying it was a screening test and the only result is reactive or non-reactive. On my 3rd call, they were able to confirm that they used a 4th gen CMIA. They also said that they will talk to their staff to avoid confusion in the future. What added to my confusion was that the doctor who I spoke with told me that my results (regardless of what method is used) is inclusive until the 3rd month. This is in total contrast to the information given to me by the second lab where I had my second test on the 27th day. They confirmed that they used a 4th gen CMIA and the results are good as conclusive on the day that I took the test but I can take it again on the 6th week just to be sure.

The results on both tests look the same though. It says HIV Ag/Ab with a cut off value and a number. However, again, upon reading online, some people's results (who took the Ag/Ab test) also show antigen and antibody results (unless I misunderstood it). So I'm wondering why my results only show one value if it's an antigen/antibody test. I can't seem to get a definitive answer from the labs where I took my tests.
4 gen is conclusive after 4 weeks, so it is time to move on from HIV. Nothing else in your last update about all the confusion is relevant, so there is no reason to keep studying HIV.
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