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Abstract

In summary, when patients develop thrombosis with thrombocytopenia after COVID-19 vaccination, ELISA (rather than rapid immunoassay) testing for anti-PF4 antibodies is appropriate for screening of VITT, but even when positive results are obtained, a definitive diagnosis should be made based on positive test results in a suitable platelet activation assay. The intriguing case reported by De Bruyne et al (1) suggests that on rare occasions vaccination might trigger or exacerbate SLE with APS.