Congenital thrombotic thrombocytopenic purpura diagnosed by recurrent reductions and rapid recoveries during infections

Abstract

Congenital thrombotic thrombocytopenic purpura (cTTP), a rare hereditary disorder caused by pathogenic variants of a disintegrin-like and metalloproteinase with thrombospondin type 1 motifs 13 (ADAMTS13) gene, leads to severely reduced enzymatic activity and microvascular thrombosis. Recurrent thrombocytopenia typically occurs in early childhood. However, detailed reports on its decline and recovery are limited. Here, we describe the case of a 1-year-6-month-old child with cTTP who developed thrombocytopenia and anemia during infectious episodes, with only mild bleeding. Platelet counts normalized rapidly between infections. In four infectious episodes preceding the diagnosis, recovery of platelet counts and anemia within a few days without fresh frozen plasma infusion were observed. This disorder should be considered in the differential diagnosis, although thrombocytopenia resolves spontaneously or homolytic findings are minimal. ADAMTS13 activity and inhibitors should be measured.