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25467 Reptilase Time, Plasma (RTSC)

Reptilase Time, Plasma (RTSC)
Test Code: REPTSO
Synonyms/Keywords

Reptilase Time, Plasma
RT (Reptilase Time)

Useful For

Evaluation of a prolonged thrombin time: It is mainly used to confirm or exclude the presence of heparin in the specimen or specimen type

Evaluating hypofibrinogenemia or dysfibrinogenemia in conjunction with the thrombin time and fibrinogen assay

Specimen Requirements
Fasting Required Specimen Type Preferred Container/Tube Acceptable Container/Tube Specimen Volume Specimen Minimum Volume
(allows for 1 repeat)
Pediatric Minimum Volume
(no repeat)
​No ​Platelet-poor Plasma ​Citrated Blue Top Tube (BTT) ​1.0 mL ​0.5 mL
Collection Processing Instructions

1. Spin down, remove plasma, and spin plasma again.
2. Freeze plasma immediately (no longer than 4 hours after collection) at -20 degrees C, or ideally < or =-40 degrees C.

Additional Information:
1. Double-centrifuged specimen is critical for accurate results as platelet contamination may cause spurious results.
2. Each coagulation assay requested should have its own vial.

Specimen Stability Information
Specimen Type Temperature Time
​Citrated Plasma ​Frozen ​14 days
Rejection Criteria
Gross Hemolysis
​Gross Lipemia
​Gross Icterus
Interference

​The reptilase time test has limited diagnostic value when ordered as a stand-alone test.

Performing Laboratory Information
Performing Location Day(s) Test Performed Analytical Time Methodology/Instrumentation
​Mayo Clinic Laboratories ​Monday through Friday ​1 hour Optical Clot-Based
Reference Lab
Test Information

Prolonged clotting times may be associated with a wide variety of coagulation abnormalities including: Deficiency or functional abnormality (congenital or acquired) of any of the coagulation proteins, deficiency or functional abnormality of platelets, specific factor inhibitors, acute disseminated intravascular coagulation, and exogenous anticoagulants (eg, heparin, warfarin)

The prothrombin time (PT) and activated partial thromboplastin time (APTT) are first-order tests for coagulation abnormalities and are prolonged in many bleeding disorders. A battery of coagulation tests is often required to determine the cause of prolonged clotting times. The thrombin time (TT) test is used to identify the cause of prolonged APTT or dilute Russell's viper venom time (DRVVT). Reptilase time (RT) test is used to evaluate a prolonged TT.

Reptilase is a thrombin-like enzyme isolated from the venom of Bothrops atrox. Thrombin splits small fibrinopeptides A and B from fibrinogen molecules, producing fibrin monomer, which polymerizes to form a clot. Reptilase, however, splits off fibrinopeptide A but not B, which results in fibrin polymerization. In contrast to thrombin and the TT test which are inhibited by heparin, the RT is normal in the presence of heparin. Similar to the TT test, the RT is prolonged in the presence of hypofibrinogenemia and dysfibrinogenemia.

Reference Range Information
14.0-23.9 seconds
Interpretation
As seen in the following table, reptilase time can help distinguish among the various causes of a prolonged thrombin time (TT).
 
Thrombin Time
     Reptilase Time
    Causes
     Remarks
Prolonged
     Prolonged
    Hypo- or afibrinogenemia
     Ascertain by determination of fibrinogen
Prolonged
     Prolonged
    Dysfibrinogenemia
     Ascertain by specific assay
Prolonged
     Normal
    Heparin or inhibitor of thrombin
     Differentiate by human TT and/or heparin assays
Prolonged
     Prolonged
    Fibrin(ogen) split products (FSP)
     Ascertain by FSP or D-dimer assay
 
Outreach CPTs
CPT Modifier
(if needed)
Quantity Description Comments
​85635
Synonyms/Keywords

Reptilase Time, Plasma
RT (Reptilase Time)

Ordering Applications
Ordering Application Description
If the ordering application you are looking for is not listed, contact your local laboratory for assistance.
Specimen Requirements
Fasting Required Specimen Type Preferred Container/Tube Acceptable Container/Tube Specimen Volume Specimen Minimum Volume
(allows for 1 repeat)
Pediatric Minimum Volume
(no repeat)
​No ​Platelet-poor Plasma ​Citrated Blue Top Tube (BTT) ​1.0 mL ​0.5 mL
Collection Processing

1. Spin down, remove plasma, and spin plasma again.
2. Freeze plasma immediately (no longer than 4 hours after collection) at -20 degrees C, or ideally < or =-40 degrees C.

Additional Information:
1. Double-centrifuged specimen is critical for accurate results as platelet contamination may cause spurious results.
2. Each coagulation assay requested should have its own vial.

Specimen Stability Information
Specimen Type Temperature Time
​Citrated Plasma ​Frozen ​14 days
Rejection Criteria
Gross Hemolysis
​Gross Lipemia
​Gross Icterus
Interference

​The reptilase time test has limited diagnostic value when ordered as a stand-alone test.

Useful For

Evaluation of a prolonged thrombin time: It is mainly used to confirm or exclude the presence of heparin in the specimen or specimen type

Evaluating hypofibrinogenemia or dysfibrinogenemia in conjunction with the thrombin time and fibrinogen assay

Reference Range Information
14.0-23.9 seconds
Interpretation
As seen in the following table, reptilase time can help distinguish among the various causes of a prolonged thrombin time (TT).
 
Thrombin Time
     Reptilase Time
    Causes
     Remarks
Prolonged
     Prolonged
    Hypo- or afibrinogenemia
     Ascertain by determination of fibrinogen
Prolonged
     Prolonged
    Dysfibrinogenemia
     Ascertain by specific assay
Prolonged
     Normal
    Heparin or inhibitor of thrombin
     Differentiate by human TT and/or heparin assays
Prolonged
     Prolonged
    Fibrin(ogen) split products (FSP)
     Ascertain by FSP or D-dimer assay
 
For more information visit:
Performing Laboratory Information
Performing Location Day(s) Test Performed Analytical Time Methodology/Instrumentation
​Mayo Clinic Laboratories ​Monday through Friday ​1 hour Optical Clot-Based
Reference Lab
For billing questions, see Contacts
Outreach CPTs
CPT Modifier
(if needed)
Quantity Description Comments
​85635
For most current information refer to the Marshfield Laboratory online reference manual.