Identification of a Rare New Cause of (Cerebral Venous Sinus) Thrombosis and Thrombocytopenia

Background/Purpose: A previously healthy 6-year-old child presented to our ER with headache, fever, and vomiting. Blood tests revealed severe thrombocytopenia and elevated D-dimer. A CT scan showed extensive cerebral venous sinus thrombosis (CVST). The most common causes for CVST in children, including coagulopathies, heart defects, oropharyngeal infections, or meningitis, were ruled out. The thrombocytopenia, as well as the thrombosis in an unusual location, reminded one of heparin-induced thrombocytopenia (HIT) or the lately discovered vaccine-induced immune thrombocytopenia and thrombosis (VITT). Patients with VITT typically present with thrombocytopenia, thrombosis (often CVST), and elevated D-dimer after an adenovirus-based COVID-19 vaccination. In HIT, as well as in VITT, anti-PF4 antibodies play a causative role.

Methods: Due to the similar clinical presentation, we screened for VITT antibodies.

Results: The PF4/polyanion enzyme-immunoassay, as well as the confirmatory PF4-induced platelet activation test, was strongly positive, confirming pathological VITT-like anti-PF4 antibodies in our patient.

Conclusion: But our patient had not received heparin, and he was not vaccinated against COVID-19. However, he had suffered from a viral infection for some days prior to hospital presentation, and a PCR test revealed adenovirus as the culprit. These data propose a potential link between (adenoviral) infection and VITT-like syndrome, potentially based on similar pathomechanisms that underlie VITT. Our research consortium was able to identify eight additional patients with a VITT-like disorder but without prior adenovirus-based vaccination or heparin exposure. They all tested positive for VITT-like anti-PF4 antibodies. Interestingly, five of the nine patients reported an infection prior to presentation. The discovery of this new VITT-like disorder and cause of severe thrombosis might have diagnostic and therapeutic consequences in the future, and clinicians have to be made aware of this newly discovered disorder.

Publication History

Article published online:
26 September 2025