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RCSI research finds blood-clotting imbalance persists in long COVID

  • Research

New research from RCSI University of Medicine and Health Sciences, published in the Journal of Thrombosis and Haemostasis, has provided greater insight into the causes of long COVID syndrome.

Long COVID syndrome is a broad collection of symptoms including shortness of breath, fatigue and reduced physical fitness that can continue for many months after initial infection with COVID-19.

Understanding is limited about why these symptoms persist in some patients but not others, and the novel syndrome remains a considerable clinical challenge for both doctors and patients alike.

To gain a new understanding of what causes long COVID, the research team analysed blood from 50 patients with long COVID syndrome up to 12 weeks post-infection with the SARS-CoV-2 virus. They compared the samples to 'controls', blood from healthy people who did not have long COVID syndrome.

The study found that the blood of patients with long COVID syndrome had higher levels of a blood-clotting booster called von Willebrand factor (VWF), and lower levels of a protein that normally breaks down VWF, called ADAMTS13. Their analysis also suggests that blood vessels were still being damaged long after the initial infection, and that specific cells of the immune system were at abnormal levels in patients with long COVID.

The study was carried out by clinical colleagues at St James's Hospital and researchers at RCSI as part of the Irish COVID-19 Vasculopathy Study (ICVS) collaboration, which includes scientific researchers in RCSI, Trinity College Dublin and University College Dublin, as well as clinical partners in St James's, St Vincent's and Beaumont Hospitals. 

The ICVS is supported by a Health Research Board COVID-19 Rapid Response award (COV19-2020-086), and a philanthropic grant from the 3M Foundation to RCSI in support of COVID-19 research.

You can read the research published in the Journal of Thrombosis and Haemostasis here.


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