TABLE 1

Characteristics of Medical Record Validated Cases of Immune Thrombocytopenic Purpura (n = 197)

Age GroupsTotal
6 wk to 11 mo12–23 mo24–59 mo5–10 y11–17 y
Total ITP cases, n1730635532197
Male, %775047445651
Platelet count at diagnosis in thousands/µL, mean1391271010
Hematology consultation, %9480919610093
Nonexclusionary acute illnessa within 6 wk before diagnosis, %776050394450
Nonexclusionary medicationb within 6 wk before diagnosis, %291320202521
Nonexclusionary acute illnessa at presentation, %293317251322
Diagnosis type, %
 Acute94838805979
 Chronic61716163819
 Unknown002432
For acute cases, mean time to resolution in days222145413636
Serious adverse events, %002563
  • ITP, immune thrombocytopenic purpura.

  • a Exclusionary acute illnesses included Epstein-Barr virus, varicella, sepsis/possible sepsis, bacteremia

  • b Exclusionary medications included sulfa drugs and antiepileptics such as valproic acid and carbamazepine; nonexclusionary medication means that the case was exposed to a medication, but that medication is not known to cause thrombocytopenia