Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a very rare side effect that can occur 5 to 30 days after immunization with the Astra Zeneca ChAdOx1 nCoV-19 vaccine. VITT has a mortality rate of approximately 30-60%. VITT is characterized by heparin-independent platelet factor 4 (PF4) antibodies, and first-line treatments include non-heparin anticoagulants and high dose intravenous immune globulin (IVIG). As described in The New England Journal of Medicine, plasma exchange therapy may be beneficial for patients who do not respond to first-line treatments. Three women (ages 45, 46, and 48 years old) with refractory VITT; all had thrombocytopenia and high D-dimer counts after treatment with IVIG. Plasma exchange was initiated four to six days after diagnosis and failed treatment with IVIG. Argatroban was also given before, during and after the plasma exchanges. Two patients recovered, and the third survived but underwent a partial leg amputation. Additional studies are needed to determine the best treatments for VITT, including the best anticoagulation regimen. However, therapeutic plasma exchange may be beneficial to patients with refractory VITT.
Reference: