Clots in the U.S.
In the U.S., a
Miami physician died following complications of
immune thrombocytopenic purpura (ITP) after his first dose of the Pfizer COVID-19 vaccine. ITP is a rare autoimmune condition in which the body generates autoantibodies to its own platelets, resulting in low platelet counts, blood clots, and bleeding if the platelet count drops very low. About 50,000 adults are diagnosed with ITP in the U.S. per year. Risk is increased in young women and people with other autoimmune conditions.
In a
case series, James Bussel, MD, and colleagues reviewed 20 reports of thrombocytopenia after receipt of the Pfizer and Moderna COVID-19 vaccines in the U.S. Bussel is professor emeritus of pediatrics at Weill Cornell Medical College in New York City who has published extensively on ITP. His group found that 17 of these patients did not have pre-existing thrombocytopenia. Patients' median age was 41 and 11 were women.
"It is not surprising that 17 possible de novo cases would be detected among the well over 20 million people who have received at least one dose of these two vaccines in the United States as of February 2, 2021," they wrote in the
American Journal of Hematology. "The incidence of an immune‐mediated thrombocytopenia post SARS‐CoV‐2 vaccination appears either less than or roughly comparable to what would be seen if the cases were coincidental following vaccination, perhaps enhanced somewhat by heightened surveillance of symptomatic patients."
However, they note that "all but one" of these cases occurred after the first dose of the Pfizer or Moderna vaccine.
"One would assume that if the vaccination was unrelated to development of ITP, case occurrences would divide more evenly between the two doses," they write. "...[W]e cannot exclude the possibility that the Pfizer and Moderna vaccines have the potential to trigger de novo ITP (including clinically undiagnosed cases), albeit very rarely."
https://www.medpagetoday.com/special-reports/exclusives/91813