A novel mutation in ADAMTS13 of a child with Upshaw-Schulman Syndrome

Abstract

Dear Sirs, Upshaw-Schulman syndrome (USS) is a rare life-threatening congenital disorder characterised by a thrombotic thrombocytopenic purpura (TTP), associated with an inherited deficiency of the von Willebrand factor-cleaving protease ADAMTS13. Mutations in the ADAMTS13 have been identified in congenital TTP patients (1, 2), most of whom have initial episodes during infancy or in early childhood (< 10 years of age), but may also manifest the condition during adolescence and adulthood (3-5). The exact incidence of congenital TTP has not been established, but is less than 1/1,000,000 persons/year. However, some authors have suggested that its incidence may be greatly underestimated. Indeed, ADAMTS13 mutations have been found in patients who were initially diagnosed with idiopathic thrombocytopenic purpura (ITP), atypical haemolytic uraemic syndrome or Evans syndrome (6-8). Here, we

Congenital thrombotic thrombocytopenic purpura (Upshaw–Schulman syndrome) caused by novel ADAMTS13 mutations

“…Cys908Tyr, found in in Proband 2, was described in a Japanese patient with a neonatal onset of TTP who was homozygous for the mutation (Matsumoto et al , ). Both mutations were reported to cause secretion defect (Perez‐Rodriguez et al , ). Interestingly, Cys908Tyr has been reported mostly in Japanese patients with USS (Fujimura et al , ).…”

“…Interestingly, the father of Proband 1, who was a carrier of Cys433Gly, had a significantly decreased ADAMTS13 activity (6%) but had no symptoms. This raises the possibility of the presence of other factors influencing the activity (Perez‐Rodriguez et al , ).…”