The NVRL has introduced a change in the way positive Treponema pallidum particle Agglutination (TPPA) results are reported. Previously, samples generating a positive TPPA result were reported as TPPA Positive ≥1/80 however from February 2016, the specific titre of the results up to and including TPPA positive 1:10240 will be reported. Samples which are reactive above this level will be reported as TPPA positive ≥1:20480.
Reporting results in this manner will provide more information when diagnosing a new/acute infection or documenting waning maternal antibody in infants.
