FTA‑ABS
Also known as: Fluorescent Treponemal Antigen, Syphilis Confirmation Test, Treponemal Antibody Fluorescent FTA
Use
The FTA‑ABS (Fluorescent Treponemal Antibody-Absorption) test is used to detect specific treponemal antibodies to Treponema pallidum, the causative agent of syphilis, serving as a confirmatory assay after initial screening tests. It is appropriate for patients aged 1 year and older to help confirm or rule out active or prior syphilis infection following nontreponemal testing.
Special Instructions
Test is only available for individuals ≥1 year of age. For patients under 1 year of age, refer to test code 34323X (Treponema pallidum Antibody [IgG, IgM] Panel, IFA).
Limitations
Not to be used in infants under 1 year of age. As a confirmatory treponemal test, FTA‑ABS may remain positive for life even after treatment, and cannot distinguish active from past infection. Interpretation should be made in context with clinical presentation and nontreponemal testing results.
Methodology
Immunoassay (Indirect Immunofluorescence Assay)
Biomarkers
Result Turnaround Time
1-3 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1‑2 mL
Minimum Volume
0.2‑1 mL
Container
Red top (no additive)
Storage Instructions
Refrigerate‑OK / Frozen‑OK / Ambient‑OK
Causes for Rejection
Gross hemolysis; gross lipemia
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 7 Days |
| Refrigerated | 14 Days |
| Frozen | 30 Days |