National researchers present first findings on blood clotting after COVID-19 vaccination

3d rendering of red blood cells in vein

Researchers have published the first findings on the diagnosis of patients with vaccine-induced immune thrombocytopenia and thrombosis (VITT), a new thrombotic syndrome associated with the COVID-19 vaccine.

The paper looked at symptoms, signs and outcomes of the first 220 UK cases of VITT.

The research team, led by Dr Sue Pavord of Oxford University Hospitals (OUH) NHS Foundation Trust, found that the overall mortality rate of those presenting to hospitals with definite or probable VITT was 23%.

Dr Pavord, a Consultant Haematologist at OUH, said: “It’s important to stress that this kind of reaction to the Oxford-AstraZeneca vaccine is very rare. In those aged under 50, this happened to around one in 50,000 people who have received the vaccine. But our study shows that for those who develop VITT, it can be devastating: it often affects young, otherwise healthy vaccine recipients and has high mortality. It is particularly dangerous when the patient has a low platelet count and bleeding in the brain.

“VITT is a very new syndrome, and we are still working out what the most effective treatment is, but identifying prognostic markers has helped to determine what is the more effective way to manage the condition.”

The Expert Haematology Panel – which included Dr Will Lester of BHP founder-member University Hospitals Birmingham – conducted daily meetings during this period to support UK haematologists with patient diagnosis and management.

Dr Will Lester explained: “The results of our study are helping guide the best possible treatments for the small numbers of people presenting to hospital with VITT. Everyone on the panel knows the importance of the vaccination programme both in the UK and around the world, and we hope our guidance for managing this condition will prove useful to clinicians across the globe.”

85% of the patients studied were under the age of 60.  Almost all of those presenting to hospital experienced the condition between five and 30 days after their first vaccination. There was no difference in incidence between the sexes, and no prior medical condition was seen more often than expected for the general population.

Dr Lester and his specialist haematology colleagues at UHB, Dr Gill Lowe and Dr Charles Percy, have been providing care and support for patients and families affected by VITT across the West Midlands region and also contributing to ground breaking laboratory research into VITT in collaboration with colleagues at fellow BHP founder-member the University of Birmingham.