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Severe Headache, Blood Clots and Low Platelet Counts

Yesterday we learned that there would be a PAUSE in the administration of the Johnson and Johnson vaccine in order for the CDC and FDA to carefully review 6 cases of unusual blood clots associated with thrombocytopenia (decreased platelets).  The blood clot is in the veins of the brain (called central venous sinus thrombosis - CVST) or even more rarely in the veins in the abdomen.  The CDC and FDA together decided to PAUSE while they carefully studied these patients, one of whom died. The incidence of this type of clot in unvaccinated patients is 2-14 per million patients,  In this study there were 6 cases in almost 7 million J & J vaccinations in the US. or a risk of 1 per million.  What makes this CVST different is the severely decreased platelet count that occurs with it. 

Patients with CVST develop severe headaches, abdominal pain, leg pain, or shortness of breath and should consult a physician. This is not the flu-like headache seen 1-2 days after vaccination. The 6 women were between the ages of 18-48 and the onset of the thrombosis occurred 6-13 days after the vaccination.  A complete blood count should be done in addition to imaging studies to identify the clot and document the decreased platelet count.  Patients with venous clots are usually treated with heparin, but it is contraindicated in these patients - which is one of the reasons that the CDC and FDA wanted to PAUSE the vaccinations so physicians could be alerted to the possible diagnosis and correct treatment.  See Below


Scientists want to see if they can identify any underlying risk factors, or specific patient groups that should not get the J&J vaccine.    Oral Contraceptive drugs did not seem to be the common factor.  At this time it appears as if this syndrome is due to the development of autoimmune antibodies, which activate the platelets and cause clotting.  These same types of clots, with thrombocytopenia, is also found after the AstraZeneca vaccines and groups of scientists here and abroad are already studying these events and changes in the coagulation system.  Note: both the J and J vaccine and Oxford-AstraZeneca vaccines use a harmless adenovirus to carry the spike protein DNA into cells so spike protein can be made and stimulate an immune response.  Pfizer and Moderna are messenger RNA vaccines - a different platform for vaccine production. 

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