Ordering Recommendation

Recommended test for syphilis screening (reverse algorithm).

New York DOH Approval Status

This test is New York state approved.

Specimen Required

Patient Preparation

Serum Separator Tube (SST).

Specimen Preparation

Separate from cells ASAP or within 2 hours of collection. Transfer 1 mL serum to an ARUP Standard Transport Tube. (Min: 0.2 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)


Semi-Quantitative Enzyme-Linked Immunosorbent Assay




1-8 days

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 Rapid Plasma Reagin (RPR) with Reflex to RPR Titer or T. pallidum Antibody by Particle Agglutination (2007443) is recommended for follow-up of positive results. For CSF specimens, the Treponema pallidum (VDRL) Cerebrospinal Fluid with Reflex to Titer (0050206) test is recommended.

Compliance Category



Hotline History


CPT Codes



Component Test Code* Component Chart Name LOINC
0050920 Treponema pallidum Ab, IgG by ELISA 51838-1
* 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
Treponema pallidum Antibody, IgG by ELISA