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Tertiary syphilis and Prozone phenomenon

1.  I had an unprotected exposure about 6 years ago.  I don't know if I already in tertiary stage for syphilis as after 6 years with hardly visible symptoms through out these years such as rashes or chancre sore, but I suspect could be in Tertiary Stage as is more than 6 years already.

I plan to get EIA Syphilis after doing some research online as it's the newer Treponemal test that able to rule out false negative in Non-Treponemal test.  However after doing some research I found a table chart in
(https://www2a.cdc.gov/stdtraining/self-study/syphilis/self_study_syphilis_diagnostic_2.html) about the sensitivity of various serological tests by stage of syphilis I found that there is "NO" figure in Tertiary Stage.  

1.1  My question here is do based on the table chart does it mean EIA is not suitable for anybody in Tertiary Stage which might fall into false negative too?   Or there might be certain error that the author miss out to fill Tertiary Stage column?


2.  I have searched a lot of information which answered by H. Hunter Handsfield, MD about the Prozone Phenomenon doesn't occur in newer EIA Syphilis tests one of it is in (http://www.medhelp.org/posts/STDs/Syphilis/show/1600085) that "The Prozone Phenomenon -- which, as you learned in your own research, can result in false negative syphilis blood tests -- ONLY is a potential problem (and a rare one at that) with the older, "nontreponemal" blood tests, like VDRL and RPR.  It does not occur with the newer EIA syphilis tests.  

However, recently I have come across a section "False-Positive And False-Negative Serological Reactions" in  (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2095002/) that mentioned "Both types of tests can also yield false-negative results due to the prozone phenomenon".  Which include Treponemal and Non-Treponemal Test.  Such false-negatives occur in 1% to 2% of patients, especially in pregnant women and HIV patients".

I know "prozone phenomenon" is rare in Non-treponemal test(RPR or VDRL).
2.1  My question is it mentioned "Both types of tests can also yield false-negative results due to the prozone phenomenon" mean it only apply to pregnant women, HIV patients or due to the the serum is not diluted slightly (with a saline solution) before being tested(Prozone phenomenon)??

2.2  Will a person in LATE LATENT or TERTIARY STAGE will still show POSITIVE result in (EIA Syphilis, FTA-ABS and TPHA test)?
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Avatar universal
Sorry please ignored my original 2.1 question as wrongly posted, the correct question will be:

2.1  Why does it mentioned "Both types of tests can also yield false-negative results due to the prozone phenomenon"? This might as well include EIA syphilis test that mentioned by Dr HHH which doesn't occur prozone phenomenon?
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