Serum immunoglobulin levels at onset: association with the prognosis of childhood idiopathic thrombocytopenic purpura.

Between 1981 and 2000, 87 patients with new diagnoses of idiopathic thrombocytopenic purpura (ITP) were admitted to the pediatric department of Kobe City General Hospital or Nishi-Kobe Medical Center. The patients' clinical records were analyzed for the relationships of disease outcome to serum immunoglobulin levels and other factors, including sex, onset age, and initial platelet counts. The disease of 22 patients became chronic, and of the 65 patients with an acute form of the disease, 27 exhibited levels of immunoglobulin G (IgG), IgA, or IgM above the 97.5% confidence limits of the age-matched control subjects. However, only 2 patients with the chronic form of the disease showed elevated serum immunoglobulin levels. The presence of antecedent specific viral infections was also associated with the acute disease form. In predicting the prognosis of childhood ITP, high serum immunoglobulin levels at initial presentation can be considered a good prognostic marker for the acute form of the disease.