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Available Tests

  • TP-PA: Treponema pallidum Particle Agglutination, Syphilis Serology: TP-PA Serum

TP-PA: Treponema pallidium Particle Agglutination, Syphilis Serology: TP-PA Serum

Tube Type

Test ID   LAB5172
EPIC Order
CPT Code(s)   86780
Group/Individual Test   Individual
Laboratory   Clinical Immunology
Tube Station   30
Specimen Routine: 0.5 mL blood/Serum Separator Tube/Gold Top: See Comments for additional information
Availability Routine: 1 run/week
Turnaround Time   1-7 days
Reference Range   Non-reactive
Comments The Treponema pallidum particle agglutination (TP-PA) test is used as a confirmatory test for samples demonstrating reactive rapid plasma reagin (RPR) test results.  Once positive, treponemal antibodies typically remain positive for years in contrast to non-treponemal antibody titers that may decline during late syphilis or with effective therapy.   The TP-PA test is performed as a reflex test on reactive RPR samples.  It may be performed on non-reactive RPR samples upon request if late syphilis is suspected.  Results are reported as reactive or non-reactive.  Rarely, an indeterminate result may be obtained.

Reviewed by jcayless on December 02, 2019

Note: Reference ranges provided on this web site are for guidance only, and may not reflect the most recent changes. Refer to laboratory reports for current reference data.

UNC Hospitals
McLendon Clinical Laboratories
101 Manning Drive
Chapel Hill, NC 27514