What is PF4 blood factor?
Platelet factor 4 (PF4, CXCL4) is a 7.8 kDa, 70-amino-acid protein. It is very abundant in platelet α-granules,59 and its levels are estimated at 12±5 ng/106 platelets. 6. PF4 exerts its angiostatic effect via inhibition of binding of different growth factors such as FGF and VEGF to cells.
What causes PF4?
Increased PF4 levels are observed in inflammatory or infectious disease [39, 40], diabetes [41], cardiovascular and renal disease [42–44], atherosclerosis [45] and other conditions affecting vascular health [41, 46–48] or in response to traumatic medical procedures [49–51] or cardiopulmonary bypass [52].
What is PF4 Polyanion?
PF4 binds to polyanions expressed on the cell wall of a wide variety of Gram-negative and Gram-positive bacteria and plays a role in bacterial host defense3,4. Binding of PF4 to polyanions results in its conformational change5 and exposes the binding site(s) for anti-PF4/P-ABS.
How is heparin induced thrombocytopenia diagnosed?
HIT can often be diagnosed by measuring the platelet count and PF4 antibody level in the blood. Symptoms of new blood clot formation may suggest HIT.
What is a positive PF4?
A positive result is indicative of the presence of H/PF4 complex antibodies. However, this test’s specificity is as low as 20% to 50% for clinical diagnosis of HIT, depending on the patient population studied.
What is serotonin release assay?
The LabCorp Serotonin Release Assay (SRA) employs washed donor platelets and detects their activation by measuring the release of endogenous serotonin that is induced by addition of patient serum in the presence of heparin.
What is the PF4 antibody test?
A test for heparin-induced thrombocytopenia (HIT) antibody, also called heparin-PF4 antibody, is performed to detect antibodies that develop in some people who have been treated with heparin.
What is a PF4 test?
What are the warning signs of HIT?
What Are the Symptoms of HIT?
- Skin tenderness.
- Swelling.
- Skin that’s warm to the touch.
- Shortness of breath.
- Change in heart rate.
- Sharp pain in your chest.
- Dizziness.
- Anxiety.
What are the symptoms of heparin-induced thrombocytopenia?
What is PF4 Elisa?
The PF4 ELISA is a serologic assay that provides laboratory support for the clinical diagnosis of HIT, but it is often positive in patients who do not have the syndrome.
