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Order Code CH291
Turnaround Time 72 hours
Test Includes

Treponema pallidum Ab

Specimen Requirements
Specimen Source
Transport Container
(Specimen Container)

Serum Separator Tube (SST)

Preferred Specimens
1 mL serum
Minimum Volume (uL)
0.2 mL
Collection Instructions
(Transport Temperature)
Transport at Room Temperature
Specimen Stability
Temperature Period
Room temperature 7 days
Refrigerated 14 days
Frozen 30 days
Reject Criteria

Gross hemolysis
Grossly lipemic

Test Details
Immunofluorescent Assay (IFA)
Clinical Significance

The FTA-ABS is a specific treponemal assay to detect antibody to T. pallidum. The FTA-ABS becomes reactive 4-6 weeks after infection. Unlike the nontreponemal tests, once the FTA-ABS test becomes reactive, it will remain reactive for many years. Since the reactivity found with the FTA-ABS does not indicate response to therapy, it is not suitable for monitoring treatment. The FTA-ABS test does not distinguish between syphilis and other treponematoses such as yaws, pinta and bejil.

Reference Ranges