| |
|
|
|
|
||||||||||||||||||||
                |
There are three types of laboratory assays available:
The functional assay (SRA) is performed by measuring radioactive serotonin release from washed platelets in the presence of the patient’s serum and an appropriate concentration of heparin. The HIPA measures the activity of the antibody/PF4/heparin complex.[38] Immunoassays detect the presence of HIT antibodies. [38] Studies performed in the 1980s demonstrated that platelet aggregation assays are much less sensitive than the SRA. [38] How do SRA, HIPA and immunoassays compare?The immunoassays are more likely to detect clinically insignificant HIT antibodies, compared with the more sensitive washed platelet aggregation assays. Therefore, these assays are more likely to be falsely positive than the SRA. On the other hand, a negative antigen assay is better at ruling out the presence of antibodies.[38]How is the more recent PIFA® method different from other testing methods?Most testing methods take hours to perform. Because of the turnaround time and the special instrumentation needed, most tests are not conducive to cost-effectively or efficiently processing single patient samples. PIFA® is a single-use, single patient test that can determine a patient’s HIT antibody status in approximately 10 minutes. [41, 42]Comparative chart of laboratory testing for HIT[38-42]
The www.argatroban.com web site contains links to third-party Web sites on the Internet. These links are provided as a service to individuals interested in more information in HIT. These sites are not part of this GlaxoSmithKline (GSK) Web site. The content and materials in these third-party Web sites are not produced or endorsed by GSK and may refer to uses of our products that are not recommended by GSK. Indications Important Safety InformationAs with all anticoagulants, bleeding is a serious concern. Argatroban is contraindicated in patients with overt major bleeding or those with hypersensitivity to the product or any of its components. Argatroban should be used with extreme caution in disease states or other circumstances in which there is an increased risk of hemorrhage. Overall major bleeding was reported in 5.3% of patients with HIT treated with Argatroban versus 6.7% of the historical controls. Overall major bleeding was reported in 1.8% of patients undergoing PCI treated with Argatroban versus 3.1% of the historical controls. Intracranial bleeding was not observed in the 568 patients treated with Argatroban for HIT (with or without thrombosis) or in the 91 patients who underwent PCI. The most common nonhemorrhagic side effects in HIT patients, regardless of the relationship to treatment, were dyspnea, hypotension, and fever. In patients undergoing PCI, the nonhemorrhagic side effects, regardless of the relationship to treatment, included chest pain, hypotension, and back pain. Please see full Prescribing Information for additional safety information on Argatroban. |
