Activated Partial Thromboplastin Time, Plasma
Use
The activated partial thromboplastin time (APTT) assay is used to evaluate the integrity of the intrinsic/common coagulation pathway, monitor patients on heparin therapy, screen for coagulation factor deficiencies, and detect inhibitors such as lupus anticoagulant and specific factor inhibitors. It helps ensure accurate management of coagulation disorders and therapy monitoring.
Special Instructions
Double-centrifuged specimen is critical for accurate results as platelet contamination may cause spurious results.
Limitations
APTT results can be affected by various commonly administered drugs, and may not detect all lupus anticoagulants, antiphospholipid antibodies, or coagulation inhibitors. Improper specimen collection and handling can lead to spurious results. Specific factor inhibitors and low levels of intrinsic factors can result in abnormal values.
FDA ApprovedNew York Approved
Methodology
Automated Analyzer (Coagulation)
Biomarkers
LOINC Codes
- 14979-9
- 14979-9
Result Turnaround Time
1 day
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
1 mL
Minimum Volume
0.5 mL
Container
Light-blue top (3.2% sodium citrate)
Collection Instructions
Centrifuge, remove plasma and centrifuge plasma again. Aliquot plasma into plastic vial leaving 0.25 mL in the bottom of centrifuged vial.
Storage Instructions
Frozen (preferred); ambient stability for 4 hours.
Causes for Rejection
Gross hemolysis
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 4 hours |
| Frozen | 30 days |