A case of congenital thrombotic thrombocytopenic purpura presenting with renal dysfunction in adulthood caused by a novel compound heterozygous ADAMTS13 mutation

Congenital thrombotic thrombocytopenic purpura (cTTP) is a rare autosomal recessive genetic disorder caused by mutations in the ADAMTS13 gene. We report a 36-year-old male cTTP patient with three compound heterozygous mutations. The patient was admitted for acute thrombocytopenia, with a 5-year history of chronic thrombocytopenia and 3 months of renal dysfunction. Initially diagnosed with immune thrombocytopenia, he was treated with glucocorticoids and the thrombopoietin receptor agonist, which provided temporary relief but failed to prevent recurrent thrombocytopenia. Ultimately, cTTP was confirmed by severely reduced ADAMTS13 activity (3.81%), the absence of ADAMTS13 inhibitors, and the identification of compound heterozygous mutations, including one novel pathogenic variant. Genetic analysis of the entire family helped in the characterization of the inheritance of this mutation. The patient was treated with fresh frozen plasma and later with prophylactic infusions. No clinical relapses occurred during follow-up.