Test ID PSPT Phosphatidylserine/Prothrombin Antibody, IgG and IgM, Serum
Useful For
Preferred second-tier panel for the detection of IgG and IgM antibodies against phosphatidylserine/prothrombin complex in patients with strong suspicion of antiphospholipid syndrome (APS) who are negative for the APS criteria laboratory tests (lupus anticoagulant, IgG and IgM anticardiolipin/beta 2-glycoprotein I, and anti-beta 2-glycoprotein I antibodies)
May be useful for the evaluation of patients with prior positive lupus anticoagulant results who are on direct oral anticoagulant therapy
May be useful as a risk marker for thrombosis in antiphospholipid antibody carriers
Profile Information
Test ID | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
PSPTG | PS/PT Ab, IgG, S | Yes | Yes |
PSPTM | PS/PT Ab, IgM, S | Yes | Yes |
Method Name
Reporting Name
PS/PT Ab, IgG/IgM, SSpecimen Type
SerumOrdering Guidance
Cardiolipin and beta-2 glycoprotein testing are the first-tier test options for most patients. Phosphatidylserine/prothrombin antibodies are considered part of the second-tier workup.
Specimen Required
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 0.5 mL
Collection Instructions: Centrifuge and aliquot serum into a plastic vial.
Specimen Minimum Volume
0.4 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 21 days | |
Frozen | 21 days |
Reference Values
Negative ≤30.0 U
Borderline 30.1-40.0 U
Positive ≥40.1 U
Day(s) Performed
Wednesday
Report Available
2 to 8 daysPerforming Laboratory

CPT Code Information
86148 x 2
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
PSPT | PS/PT Ab, IgG/IgM, S | 97026-9 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
PSPTM | PS/PT Ab, IgM, S | 85358-0 |
PSPTG | PS/PT Ab, IgG, S | 85359-8 |