Common cold triggers killer blood clot disorder, scientists discover

WE all know how miserable the common cold can be.

But now, scientists are warning that your seasonal sniffles could trigger a fatal complication.

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For the first time, scientists at the University of North Carolina have found a link between a life-threatening blood clotting disorder and an adenovirus infection.

Adenovirus is one of the most common respiratory viruses affecting both adults and children, causing cold and flu-like symptoms.

Viral infections, as well as autoimmune diseases and other conditions, can cause levels of platelets in the blood to drop – known as thrombocytopenia.

Platelets, or thrombocytes, are a vital part of the blood – responsible for forming blood clots, which stop you bleeding out when you’re injured.

“This adenovirus-associated disorder is now one of four recognised anti-PF4 (anti-platelet factor 4) disorders,” said Dr Stephen Moll, professor of medicine at the university’s Department of Medicine’s Division of Hematology, said.

“We hope that our findings will lead to earlier diagnosis, appropriate and optimised treatment, and better outcomes in patients who develop this life-threatening disorder.”

The latest findings, published in the New England Journal of Medicine, sheds new light on how the virus can play a role in causing an anti-platelet factor 4 disorder.

The discovery paves the way for new avenues of research to understand why and how this condition occurs, the scientists said.

What are anti-PF4 disorders?

Antibodies are large proteins that stick to the surface of bacteria, viruses and other ‘foreign invaders’, highlighting them for destruction by the immune system.

In anti-PF4 disorders, a person’s immune system mistakenly creates antibodies that target the PF4 protein, which is released by platelets.

It can trigger a chain reaction that results in the platelets being destroyed by the immune system, causing excessive blood clotting and a drop in platelet levels.

In some cases anti-PF4 antibodies are triggered by a patient taking an anticoagulant drug called heparin, called heparin-induced thrombocytopenia (HIT).

In other cases, where a person hasn’t taken heparin, it’s known as spontaneous HIT.

In the last three years, a small number of cases of thrombocytopenia have been linked to specific Covid-19 jabs, distinct from those produced by Moderna and Pfizer. This condition is called vaccine-induced immune thrombotic thrombocytopenia (VITT).

To understand the condition better, researchers looked into a five-year-old boy who was previously diagnosed with an adenovirus infection and was hospitalised with a severe blood clot in his brain and significantly reduced platelet levels.

Doctors noted he hadn’t been taking heparin, or had a Covid vaccine.

“The intensive care unit physicians, the neuro-intensivist, and hematology group were working around the clock to determine next steps in the care for this young boy,” said Dr Jacquelyn Baskin-Miller.

“He wasn’t responding to therapy and was progressing quickly.

“We had questioned whether it could have been linked to his adenovirus considering the vaccine data, but there was nothing in the literature at that time to suggest it.”

The results showed that the boy had an antibody typically associated with HIT.

It followed a similar case reported in Richmond, Virginia where another patient with an adenovirus infection was found to have multiple blood clots, a stroke, heart attack, DVT as well as severe thrombocytopenia.

Like the little boy, the patient hadn’t been exposed to heparin or a Covid jab.

Test results showed that the patient’s antibodies were targeting the same protein as HIT antibodies, which concluded that they had a variant of HIT linked to the adenovirus infection.

Researchers said there are many unanswered questions on how common this disorder is and if it can be caused by other viruses – adding more research is needed.