Inhibitor Assay, PTT with Reflex to PTT 1:1 Mix, with Reflex to 1-Hour Incubation
Also known as: PTT INHIB
Use
The Inhibitor Assay, PTT with Reflex to PTT 1:1 Mix, with Reflex to 1-Hour Incubation is used for the initial screening for inhibitors in plasma. This assay is particularly useful in identifying coagulation factor deficiencies which can cause bleeding disorders. It helps in diagnosing inhibitors like lupus anticoagulants, specific factor inhibitors, as well as the effects of anticoagulation medications such as heparin. When a prolonged PTT is detected, a mixing study is performed to help differentiate between factor deficiencies and inhibitors.
Special Instructions
This test requires collection of plasma in a light blue (sodium citrate) top tube. It is crucial to submit separate specimens when multiple tests are ordered to ensure sample integrity. The specimen must be critically frozen during storage and transport to preserve its stability.
Limitations
The test is unable to provide accurate results if the specimen is serum or EDTA plasma, or if the sample is clotted or hemolyzed. Additionally, the results of the PTT test can be affected by anticoagulant medications, and therefore the test should be interpreted with clinical correlation. The test cannot directly diagnose specific coagulation disorders without additional confirmatory tests.
New York Approved
Methodology
Automated Analyzer (Clinical Chemistry)
Biomarkers
LOINC Codes
- 14979-9
Result Turnaround Time
1-2 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
2 mL
Minimum Volume
1 mL
Container
Lt. blue (sodium citrate)
Collection Instructions
Transfer 2 mL plasma to an ARUP Standard Transport Tube. Separate specimens must be submitted when multiple tests are ordered.
Storage Instructions
CRITICAL FROZEN
Causes for Rejection
Serum. EDTA plasma, clotted or hemolyzed specimens.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 4 hours |
| Refrigerated | Unacceptable |
| Frozen | 2 weeks |