How common are fta-abs false positives? concerned that my ongoing joint pain will yield positive results. tested negative last month for ana, ra, lyme, hep a b & c, and hiv. are false positives frequent for those with undiagnosed joint pain?

Falst positives are rare. But there is no need for FTA-ABS testing anyway, unless a syphilis screening test (like RPR or VDRL) is positive. You should not have an FTA-ABS test just because you have joint pains.

There can be false positives, however those can be addressed with a second treponemal antibody test. For information: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4999316/#:~:text=Treponemal%20tests%20detect%20antibody%20to,whether%20the%20disease%20is%20active.