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GTR Home > Conditions/Phenotypes > Upshaw-Schulman syndrome


Hereditary thrombotic thrombocytopenic purpura (TTP), also known as Upshaw-Schulman syndrome (USS), is a rare autosomal recessive thrombotic microangiopathy (TMA). Clinically, acute phases of TTP are defined by microangiopathic mechanical hemolytic anemia, severe thrombocytopenia, and visceral ischemia. Hereditary TTP makes up 5% of TTP cases and is caused mostly by biallelic mutation in the ADAMTS13 gene, or in very rare cases, by monoallelic ADAMTS13 mutation associated with a cluster of single-nucleotide polymorphisms (SNPs); most cases of all TTP (95%) are acquired via an autoimmune mechanism (see 188030). Hereditary TTP is more frequent among child-onset TTP compared with adult-onset TTP, and its clinical presentation is significantly different as a function of its age of onset. Child-onset TTP usually starts in the neonatal period with hematological features and severe jaundice. In contrast, almost all cases of adult-onset hereditary TTP are unmasked during the first pregnancy of a woman whose disease was silent during childhood (summary by Joly et al., 2018). [from OMIM]

Available tests

54 tests are in the database for this condition.

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Genes See tests for all associated and related genes

  • Also known as: ADAM-TS13, ADAMTS-13, C9orf8, VWFCP, vWF-CP, ADAMTS13
    Summary: ADAM metallopeptidase with thrombospondin type 1 motif 13

Clinical features


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