On April 18 I was tested and received a negative result. But at the time was told that it was possible that there could be a false negative if I was tested too soon after exposure.  I was tested again August 29 with a reactive result (RPR ((DX)) W/REFL Titer) of 1.2.   I was tested again September 1 with a reactive result of 1.4.

I am curious if the titer number indicates how long the infection existed and if I was tested too early on April 18? Or if there is some predictability in increasing titer counts as an infection progresses. 

I had prior negative results every year from 2018-2022.

FYI,  RPR titers are measured in doubling values, 1:1, 1:2, 1:4,1:8 and so forth.  THUS, because of the way that Syphilis testing is performed, a RPR titer must increase by four-fold, i.e. to be meaningfully higher, an RPR of 1:2 would need to increase to 1:8 or greater to be considered significantly increased (or, following therapy, decreased).  Thus there is no significant difference from a RPR value of 1:2 versus 1:4. They are essentially the same.

Interpretation of syphilis tests is complex. I hope the information I have provided is helpful. If any part of this response is unclear, please don’t hesitate to use your up to two follow up fors clarification EWH

I was dating someone who informed me around April 12 that he had a positive result and that his titer count had increased (he claimed that he had contracted the disease in the past and was treated but that his titer count unexpectedly rose). So I was tested April 18. At the time I was initially tested I was told that the results were negative but that due to possible exposure timeframes, it was possible that I could have a negative result if I was tested to soon after exposure.

The information that 1:2 and 1:4 are essentially the same is interesting. But given the fact that I had a negative result on every test prior to a few weeks ago, I assume I should be treated?

1.  It appears, based on the notification you received on April 12, that you were exposed to a partner recently diagnosed with syphilis. Recommendations in such situations are that individuals should be treated preventively as, on average, one in three persons exposed in this manner will go on to develop syphilis. That process of development of syphilis can take, on average three or more weeks. 

2.  Thus, it is entirely possible that you were tested too early.

3.  Based on the additional information you have provided, my strong advice would be to seek treatment for syphilis as quickly as possible. In addition it is recommended that any sexual partners that you have had since April should be notified that they may have been exposed, should be tested and should strongly consider preventive therapy, just as you should have received.

I hope this perspective helps. EWH.

One of the tests with a reactive result says it was "FTA-ABS treponemal assay". Is that what you are referring to?

Scheduled to get treatment today.

I'm glad that you are getting treated. Please let me know if there are further questions.  EWH