Treponema pallidum Antibody, IgG by ELISA
Ordering Recommendation

Recommended syphilis screening test in so-called reverse screening algorithm. The CDC recommends a nontreponemal test (RPR or VDRL) for initial syphilis screening prior to confirmation with a treponemal test (eg, TP-PA).

Semi-Quantitative Enzyme-Linked Immunosorbent Assay
1-8 days
New York DOH Approval Status
This test is New York DOH approved.
Submit With Order
ARUP Consult®
Disease Topics
Specimen Required
Patient Preparation
Serum separator tube. 
Specimen Preparation
Separate serum from cells ASAP or within 2 hours of collection. Transfer 1 mL serum to an ARUP Standard Transport Tube. (Min: 0.05 mL) 
Storage/Transport Temperature
Unacceptable Conditions
Plasma or other body fluids. Contaminated, hemolyzed, or severely lipemic specimens. 
After separation from cells: Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 year (avoid repeated freeze/thaw cycles) 
Reference Interval
Effective February 16, 2016
0.9 IV or less: Negative - No significant level of Treponema pallidum IgG antibody detected.
1.0 IV: Equivocal - Questionable presence of Treponema pallidum IgG antibody detected.  Repeat testing in 10-14 days may be helpful.
1.1 IV or greater: Positive - Presence of IgG antibody to Treponema pallidum detected, suggestive of current or past infection.
Interpretive Data
Seroconversion between acute and convalescent sera is considered strong evidence of recent infection. The best evidence for infection is a significant change on two appropriately timed specimens, where both tests are performed in the same laboratory at the same time. The Treponema pallidum Antibody (FTA-ABS), Serum, IgG by IFA (0050477) is recommended for follow-up of reactive nontreponemal tests for syphilis, and as a single test in patients suspected of late syphilis. For CSF specimens, the Treponema pallidum (VDRL) Cerebrospinal Fluid with Reflex to Titer (0050206) test is recommended.

Hotline History
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Component Test Code*Component Chart NameLOINC
0050920Treponema pallidum Ab, IgG by ELISA51838-1
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
  • Syphilis Antibody, IgG by ELISA
  • T pallidum IgG ELISA