Reptilase Time, Plasma
Use
The Reptilase Time test is useful for evaluating prolonged thrombin time (TT). It is primarily used to confirm or exclude the presence of heparin in the specimen or to evaluate hypofibrinogenemia or dysfibrinogenemia in conjunction with TT and fibrinogen assays. The reptilase time assay can help distinguish among various causes of prolonged thrombin time by evaluating clot formation when reptilase, a thrombin-like enzyme, is used instead of thrombin.
Special Instructions
Ensure that each coagulation assay requested is provided in a separate vial. The double-centrifuged specimen is critical for accurate results as platelet contamination may cause spurious results. It is essential to freeze the plasma immediately and maintain it at the recommended temperature during transit to ensure specimen stability.
Limitations
The reptilase time test has limited diagnostic value when ordered as a stand-alone test. Prolonged clotting times can be caused by a wide variety of coagulation anomalies including deficiencies or functional abnormalities in coagulation proteins or platelets, presence of specific inhibitors, acute disseminated intravascular coagulation, and influence of exogenous anticoagulants like heparin or warfarin. The standard clotting assays such as prothrombin time (PT) and activated partial thromboplastin time (APTT) along with a battery of coagulation tests are often required to accurately determine the cause of prolonged clotting times. The reptilase time test is particularly useful in cases where thrombin time is prolonged due to heparin, as the test result remains normal in such scenarios.
New York Approved
Methodology
Automated Analyzer (Coagulation)
Biomarkers
LOINC Codes
- 6683-7
- 6683-7
Result Turnaround Time
1-4 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
1 mL
Minimum Volume
0.5 mL
Container
Light-blue top (citrate) tube; Plastic vial for submission
Collection Instructions
1. See Coagulation Guidelines for Specimen Handling and Processing. 2. Centrifuge to remove plasma and centrifuge plasma again. 3. Freeze plasma immediately at -20 degrees C or ideally below -40 degrees C.
Storage Instructions
Freeze immediately at -20 degrees C or below -40 degrees C.
Causes for Rejection
Gross hemolysis, Gross lipemia, Gross icterus
Stability Requirements
| Temperature | Period |
|---|---|
| Frozen | 14 days |