Genetic predisposition to vaccine-induced immune thrombotic thrombocytopenia: is there a family link?
  • Rita Pombal
    Immunohemotherapy Department, Unidade Local de Saúde Gaia/Espinho, Vila Nova de Gaia, Portugal
  • Luciana Silva
    Internal Medicine Department, Unidade Local de Saúde Gaia/Espinho, Vila Nova de Gaia, Portugal
  • David Ferreira
    Immunohemotherapy Department, Unidade Local de Saúde Gaia/Espinho, Vila Nova de Gaia, Portugal


COVID-19 vaccines, genetic predisposition to disease, purpura, thrombocytopenic, idiopathic, thrombocytopenia


Background: Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a rare life-threatening thrombotic reaction to COVID-19 vaccines.
Case description: Two young male first cousins, with a family history of idiopathic thrombocytopenic purpura, developed VITT after the Ad26.COV2.S vaccine. Both had a favourable clinical and analytical outcome. We investigated the genetic factors that could be associated with a genetic predisposition to VITT.
Conclusions: There are no published cases where the VITT patients were relatives. The genetic study did not reveal any likely pathogenic variants, although the prevalent polymorphism c.497A>G (p.(His166Arg)) in the FCGR2A gene was found in a homozygous state. More studies are required to better understand VITT’s pathophysiology and any underlying genetic predispositions.



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    Published: 2024-05-14
    Issue: 2024: Vol 11 No 6 (view)

    How to cite:
    Pombal R, Silva L, Ferreira D. Genetic predisposition to vaccine-induced immune thrombotic thrombocytopenia: is there a family link?. EJCRIM 2024;11 doi:10.12890/2024_004546.

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