Paradoxical effect of SARS-CoV-2 infection in patients with immune thrombocytopenia.

Thrombocytopenia has been identified as a common complication of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection in the general population. In an attempt to determine the impact of coronavirus disease 2019 (COVID-19) in patients with immune thrombocytopenia (ITP), a retrospective single-centre study was performed. Thrombocytosis was observed in patients with chronic ITP after SARS-CoV-2 infection, frequently needing treatment adjustment or even discontinuation of therapy. Relapses and newly diagnosed cases showed a fast response after initial treatment compared to ITP. Reduced immune activity due to lymphopenia during COVID-19 could explain this paradoxical effect, although further studies are needed.