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Division of Consolidated Laboratory Services


Laboratory: Immunology/Virology

Test Description: Serodia Treponema Pallidum Particle Agglutination (TP-PA) is a qualitative gelatin particle agglutination assay used for the detection of Treponema pallidum antibodies in human serum or plasma as an aid in the diagnosis of syphilis. This assay is used as the confirmatory method for reactive non-treponemal syphilis (RPR).

Order Approval Required? Yes

Specimen Type: Serum

Collection Container: Red top or serum separator tube

Optimal Volume: 7 ml

Collection Guidelines: The optimal amount of specimen is 7ml of coagulated blood in a red top or serum separator tube. 1 ml of coagulated blood in a red top tube or 500uL of sera is acceptable.

Storage Container: Samples are refrigerated for 5 days in original specimen tubes. They may be aliquotted into a cryovial and are frozen in -20 °C freezer.

Storage Instructions: Samples should be stored at 2-8 °C for 5 days after collection. Serum may be aliquotted and stored at 2-8 °C for shipping or frozen at -20°C or colder.

Transportation Instructions: Ship on cold packs

Test Methodology: Agglutination by Serodia Treponema Pallidum Particle Agglutination (TP-PA)

Additional Information: (Virginia Department of Health (VDH) and Division of Consolidated Laboratory Services (DCLS) approval required prior to sample submission)

Causes For Rejection:

  • Identification on the form and tube does not match.
  • Specimen is grossly hemolyzed or lipemic.
  • Specimen has apparent contamination or particulate matter present.
  • Received insufficient quantity of sera/plasma for testing
  • Specimens were maintained under improper storage conditions or out of holding time

Possible Results: Positive, Negative, Inconclusive