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Lupus Anticoagulant by HEXA
| Item | Value |
|---|---|
| Approval req'd? | No |
| Available Stat? | No |
| Utilization Guidelines | When lupus anticoagulant testing is requested, it is appropriate to perform BOTH the RVVT and Lupus Anticoagulant by HEXA tests. For this reason, both will be performed whenever either is ordered. In the uncommon circumstance that a provider wishes to perform only one of these tests, the hematology laboratory should be contacted at 353-1747 to request that only the single test be performed. |
| Test code | HEXA |
| Test group | Anti-phospholipid |
| Performed by | Parnassus Hematology |
| Method | Hexagonal Phospholipid Neutralization Test |
| Collection Instructions | When lupus anticoagulant testing is requested, it is appropriate to perform BOTH the RVVT and Lupus Anticoagulant by HEXA tests. For this reason, both will be performed whenever either is ordered. In the uncommon circumstance that a provider wishes to perform only one of these tests, the hematology laboratory should be contacted at 353-1747 to request that only the single test be performed. 1. Check the expiration date on the label of the blue top vacutainer before drawing the patient. 2. For blood collection in a sodium citrate blue top, the tube must be filled to above the Minimum Fill Indicator on the tube. It is crucial to wait and allow the tube to stop filling before removing it from the needle. 3. With use of a butterfly needle, draw about 1 cc using a separate blue top to remove air from tubing, discard the first tube and then draw a second blue top tube filled to the full extent of the vacuum. 4. Tubes should not be filled past the Maximum Fill dashed line by either using a syringe or removing the tube cap. Bring specimen immediately to lab after collection. For patients with Hct's ≥ 55% please contact Hematology (x3-1747) to obtain blue top tubes with adjusted citrate volumes in order to maintain the proper citrate to plasma ratio for coagulation studies. NOTE: Thrombin inhibitors (e.g. hirudin, argatrbanÉ) present in the sample to be tested may interfere in the test and lead to falsely positive results, for patients receiving such therapy please contact the Hematology lab (x3-1747) BEFORE collecting samples for testing. |
| Container type | Blue top filled to full extent of vacuum |
| Amount to Collect | 2.7 mL blood |
| Sample type | Citrated plasma |
| Preferred volume | 1 mL plasma |
| UCSF Rejection Criteria | Hemolysis, sample collected in glass tube. Samples collected in outdated blue top vacutainer. Over-filled or under-filled tubes may be rejected |
| Processing notes | Platelet poor plasma required and must be frozen within 4 hours of collection. Note: If Lupius Anticoagulant ordered without further specification order both HEXA and RVVTM |
| Normal range | Negative |
| Synonyms | LA; antiphospholipid AB; Anti-cardiolipin; HEXA; RVVT; Russel's viper venom; Hexagonal phospholipid neutralization |
| Additional information | When lupus anticoagulant testing is requested, it is appropriate to perform BOTH the RVVT and Lupus Anticoagulant by HEXA tests. For this reason, both will be performed whenever either is ordered. In the uncommon circumstance that a provider wishes to perform only one of these tests, the hematology laboratory should be contacted at 353-1747 to request that only the single test be performed. For detection of lupus anticoagulants, which by definition prolong a clotting time, are inhibitors, and are phospholipid dependent. Persistent presence (> 3 months) of antiphospholipid antibodies has been associated with recurrent thrombosis syndromes. A review of testing performed on UCSF patients indicates that, of all patients diagnosed with Lupus Anticoagulants, approximately 50% are detected in both Hexagonal Phospholipid Neutralization and Russell's Viper Venom tests, 25% in only the Hexagonal Phospholipid Neutralization Test, and 25% in only the Russell's Viper Venom Test. Thrombin inhibitors (e.g. hirudin, argatroban, etc.) present in the sample to be tested may interfere in the test and lead to falsely positive results To monitor unfractionated heparin therapy in the presence of a lupus anticoagulant, Heparin Levels may be needed. |
| LOINC code | 33930-9 |
| Last Updated | 11/8/2012 3:27:31 PM |
| Entry Number | 499 |
If you have additional questions regarding this test, please call: 415-353-1667