Age at diagnosis and death in patients with hTTP. Age at diagnosis was reported for 202 (89%) of the 226 patients (85 male, 117 female). Deaths were reported for 32 patients (18 male, 14 female). Patients whose age at diagnosis or death occurred at a decade marker are counted in the following decade. Newborn infants (NBs) are distinguished from children age 0 to 9 years because they were recognized by their severe hyperbilirubinemia. Twelve infants were diagnosed at birth; 9 died. The diagnosis of newborn infants occurred within several days of birth. Among the other children age 0 to 9 years, the youngest child diagnosed with hTTP was a 1-month-old girl; the youngest death was in a 2-year-old boy.