ARUP's Laboratory Test Directory

0050777: Treponema pallidum Antibody by TP-PA

Test Mnemonic: MHA
Methodology: Indirect Hemagglutination

Performed: Mon-Fri

Reported: 1-4 days

Specimen Required:  
Collect: One 4 mL SST or PST.

Transport: 1 mL serum or plasma at 2-8°C. (Min: 0.5 mL)  Submit specimen in an ARUP Standard Transport Tube.

Pediatric Collection/Transport: 0.15 mL serum or plasma at 2-8°C.

Remarks: Separate serum or plasma from cells ASAP.

Unacceptable Conditions: CSF or other body fluids.

Stability: After separation from cells: Ambient: 2 days; Refrigerated: 2 weeks; Frozen: 1 year (avoid repeated freeze/thaw cycles)

Reference Interval:
Nonreactive

Note:
TP-PA is a helpful diagnostic aid for the patient with a reactive reagin test, but presents with atypical signs of primary, secondary, or late syphilis. TP-PA compares favorably with the FTA test, but appears slightly less sensitive in cases of untreated early primary syphilis. In late syphilis, the agreement with FTA is 99%.

VDRL is the preferred test for cerebrospinal fluid. Treponemal tests (TP-PA or FTA) are not recommended for CSF.  FTAs on CSF may be tested, but TP-PA cannot be tested on CSF.

CPT Code(s):
86781