Case series of thrombotic thrombocytopenic purpura in children and adolescents. Horton TM, Stone JD, Yee D, Dreyer Z, Moake JL, Mahoney DH. Journal of Pediatric Hematolology/Oncology 2003;25(4):336-339.

Thrombotic thrombocytopenic purpura (TTP) is a well-described entity in adults but is rarely observed in children. The authors describe a series of seven children with suspected acquired TTP. The children ranged in age from 1 to 16 years and 4 of the 7 were male. Clinical findings included petechiae, purpura, jaundice, central nervous system (CNS) events, fever, diarrhea, renal insufficiency, and hematuria. Significant CNS events included cerebral vascular accidents, altered mental status, seizures, and hemiparesis. Patients were treated with daily plasma infusions (1 of 7 patients) or plasma exchange (5 of 7 patients). Three patients had associated autoimmune diseases. Response was prompt, although relapses were frequent. Four of seven patients had at least one recurrence, two had only one recurrence, and the other two had multiple recurrences. Decreased von Willebrand factor (vWF) protease activity was found in four of five cases and vWF protease inhibitors were found in three of five cases. Two deaths occurred, including a one year old with an intracranial hemorrhage and a 12 year old with acute tubular necrosis. Although rare, TTP is a life-threatening illness that does occur in children and should be considered in the differential diagnosis of thrombocytopenia with hemolytic anemia.