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Treponemal Antibody Screen

Item Value
Approval req'd? No
Available Stat? No
Test code TREP
Test group Syphilis
Performed by Immunology
In House Availability Weekdays (day shift)
Method Enzyme Immunoassay
Collection Instructions Avoid hemolysis, transport to laboratory as soon as possible. If transport is delayed refrigerate the sample.
Container type Gold top
Amount to Collect 2 mL blood
Sample type Serum
Preferred volume 1 mL serum
Min. Volume 1.0 mL serum
UCSF Rejection Criteria Grossly lipemic, grossly hemolysed or contaminated samples
Processing notes Freeze sample and transport to CB frozen.
Normal range Non-reactive
Synonyms MHA-TP; FTA-Abs; T. pallidum; MHATP; Syphilis; Treponema pallidum
Stability Room temperature 4 hours, refrigerated 2 days, frozen > 3 days
Turn around times 1-4 days
Reflex? Yes, if positive a non-treponema test (RPR) and titer will be performed at an additional charge.
Additional information This test is a treponemal antibody test providing evidence for exposure to syphilis. The laboratory is using a 'reverse algorithm' for syphilis screening. This treponemal test is performed first, and then positive results are reflexively tested by RPR (a non-treponemal test) with titer. An RPR with titer can be ordered alone to monitor treatment of patients with known syphilis (test code RPRF).

A positive result with both the treponemal test and the RPR is considered to be positive for syphilis. A positive result with the treponemal test and a negative RPR can be seen in patients with a history of treated syphilis and also with early syphilis or very late stage syphilis. As with any serologic test, false positive results can also occur. An alternate treponemal test (such as the TP-PA) can be ordered as a send out test in discrepant cases where a false positive is suspected (call lab for send out, test code TPPA).
CPT coding 86780
Last Updated 3/31/2016 6:02:18 PM
Entry Number 947
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