Background: Idiopathic thrombocytopenic purpura(ITP) is a relatively common hematologic disease in childhood with good prognosis. But 10∼20% of the ITP patients became a chronic form. About 70% of the patients have past history of viral infection before onset of ITP, but many of them cannot know the kind of the virus. Epstein-Barr virus infection is very common in Korea and Japan, and it happens in early childhood. We studied the pattern of clinical manifestation and laboratory findings including the changes in T Iymphocyte subset in ITP patients with/without EBV infection and looked for any correlation between the disease status and the EBV infection.
Methods: Thirty-two ITP patients were included in the study between January 1995 and August 1995. Including the routine laboratory tests, antibodies for early antigen, nuclear antigen of EBV were checked. T Iymphocyte subset study was done by FACScan when there was evidence for EBV infection. The platelet count was followed up every day during IVIg therapy and 1, 2 months after treatment.
Results: Nineteen patients had evidence of EBV infection when ITP occurred. There was difference in the platelet count between the infected and control groups at the 5th day of IVIg therapy and thereafter. The platelet count became lower than 100× 109/mL in the infected group at 1 month after IVIg therapy and there was strong tendency to recur in infected group. CD4/CD8 ratio was reversed in 3 patients with EBV infection and 2 of them recurred, the rest became chronic ITP patient.
Conclusion: ITP patients with EBV infection had lower platelet level after IVIg therapy and they also showed tendency to become chronic ITP patients. This phenomenon was more when CD4/CDB ratio was reversed. In cases of age lesser than 3 months, we recommend to repeat the EBV antibody tests to overcome false negative results.