Prof. Dr. med. E. Lindhoff-Last
The Cardiovascular Center Bethanien
Thrombosis and Haemostasis
Author Interview
Letter to the Editor
Edelgard Lindhoff-Last, Linda Schoenborn, Michael Piorkowski, Joerg Herold, Andreas Greinacher, Jo-Ann Sheppard, Theodore E. Warkentin
CC BY-NC-ND 4.0
Thromb Haemost 2022; 122(02): 304-307
DOI: 10.1055/a-1701-2926
T&H
Why did you (and your colleagues) write this paper? What was its main purpose?
EDELGARD LINDHOFF-LAST
Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a rare and life threatening side effect of two adenoviral vector vaccines, ChAdOx1 nCoV-19 (AstraZeneca) and Ad26.CoV2.S (Johnson&Johnson/Janssen), which is caused by platelet-activating immunoglobulin G (IgG) that recognizes platelet factor 4 (PF4). To date, studies of VITT have emphasized concurrence of thrombocytopenia and thrombosis, occuring 5-30 days after the first COVID 19 vaccination, strongly suggesting a diagnosis of VITT. However, we observed that VITT patients can present with heterogenous clinical features ranging from isolated thrombocytopenia or sole thrombosis to the full picture of thrombocytopenia and thrombosis. Thus, the main purpose of our paper is to demonstrate the heterogeneity of clinical presentations of VITT.
T&H
What are the main conclusions?
EDELGARD LINDHOFF-LAST
Our findings have implications for clinical practice: one should be aware that VITT patients can present with diverse clinical symptoms ranging from isolated thrombocytopenia or single-site thrombosis to the full-blown picture of VITT (i.e., multiple arterial and/or venous thromboses, thrombocytopenia). The possibility that early detection and therapeutic-dose anticoagulation might prevent life-threatening thrombosis should be considered; moreover – based on our case series - mRNA vaccines may be safe for use in VITT patients, as they do not appear to restimulate anti-PF4 antibodies implicated in VITT pathogenesis.
T&H
What are the paper's implications? - to the public? -to medical professionals?
EDELGARD LINDHOFF-LAST
VITT is a new ultra-rare side effect of COVID-19 vaccination with vector-based vaccines; long-term follow-up and safety data of a second vaccination with an mRNA-COVID 19 vaccine is scarce. We demonstrate in our paper that second vaccination with an mRNA vaccine in 3 of 3 revaccinated patients with VITT was safe, i.e., spike protein antibody levels were increased with no change in anti-PF4 antibody levels. This is an important observation for VITT patients, since this patient population also needs protection from COVID-19 infections.
T&H
Are the findings clinically significant? Should the findings change practice?
EDELGARD LINDHOFF-LAST
Our findings are clinically significant in several respects: First, occurrence of thrombocytopenia or thrombosis within 30 days after a first vaccination with a vector-based COVID 19 vaccine should lead to clinical suspicion of VITT, even though these patients do not (yet) present with all clinical features expected. Second, early anticoagulation might prevent subsequent thrombosis; and third, second vaccination with an mRNA vaccine appears to be safe.
