The side effects of some vaccines for Covid-19, the dreaded thrombi, already have a treatment. Scientists from McMaster University (Canada) have shown that treatment based on a combination of anticoagulant drugs with high doses of immunoglobulin IV saves the lives of people suffering from vaccine-related blood clots.
The researchers of the Platelet Immunology Laboratory
McMaster (MPIL), whose work is published today in The New England Journal of Medicine, recommend this combination to combat immune thrombotic thrombocytopenia vaccine-induced (VITT).
The efficacy of the treatment has been tested in three Canadian patients who received the AstraZeneca vaccine and who subsequently developed VITT. Two suffered from leg thrombi and the third had clots that block arteries and veins within his brain.
“If I were a patient with vaccine-induced immune thrombotic thrombocytopenia, I would tell him that we already have treatment. We can accurately diagnose, treat it and know exactly how the treatment works, “he stresses. Ishac Nazy, scientific director of the aforementioned laboratory.
«Our job is understand this disease mechanism so that we can improve the diagnosis and management of the patient. This study is a true approach to translation medicinel, from the laboratory to the patient.
Vaccine-induced immune thrombotic thrombocytopenia occurs when antibodies attack a protein in the blood, called factor plaquetario 4 (PF4), which causes the activation of platelets in the blood, causing them to clump together and form clots. Blood samples taken from patients after treatment showed a reduction in such antibody-mediated platelet activation.
And despite the fact that all three patients in the study were older, many cases of vaccine-induced immune thrombotic thrombocytopenia have affected younger people, Nazy notes that vaccine-induced immune thrombotic thrombocytopenia is a rare disorderregardless of the age of the people.
Scientists designed a diagnostic test and treatment of thrombotic thrombocytopeniato immune-induced effective vaccines based on his previous investigations of heparin-induced thrombocytopenia (HIT).
Although these two conditions are similar, the use of a standard HIT antibody test to detect vaccine-induced immune thrombotic thrombocytopenia can produce false negative results.
This led the scientists to modify the HIT test to detect specific antibodies to vaccine-induced immune thrombotic thrombocytopenia that are found, albeit very infrequently, in patients who have been vaccinated.
Subsequent laboratory tests on blood samples from patients showed how the combination treatment based on high doses of immunoglobulin along with anticoagulant medications it turned off platelet activation and stopped clot formation.
“We now understand the mechanism that leads to platelet activation and clotting,” Nazy emphasizes.