Recombinant a disintegrin-like and metalloproteinase with thrombospondin type 1 motifs 13 (ADAMTS-13) for acute and prophylactic treatment of congenital thrombotic thrombocytopenic purpura in pregnancy.

Thrombotic thrombocytopenic purpura (TTP) is a disorder of the absence or severe depletion of a disintegrin-like and metalloproteinase with thrombospondin type 1 motifs 13 (ADAMTS-13) protease, which cleaves von Willebrand factor multimers. In its absence, exposed platelet binding sites on large von Willebrand factor multimers bind and aggregate platelets, causing microangiopathic hemolytic anemia and thrombosis. The rare congenital form of TTP (cTTP) is caused by mutations in the ADAMTS-13 gene. Pregnant cTTP patients are at very high risk of developing complications. Current recommendations for pregnant cTTP patients are prophylactic fresh-frozen plasma infusions; however, efficacy varies among patients. Recombinant ADAMTS-13 (rADAMTS-13) is a novel alternative to plasma infusions, recently reported to be effective and safe for treating nonpregnant cTTP patients. Few studies have attempted to treat pregnant cTTP patients with rADAMTS-13. We present a case of successful treatment with rADAMTS-13 for acute TTP exacerbation and maintenance during pregnancy in a cTTP patient with a history of pregnancy complications and insufficient response to plasma infusions.