Comparison of Prefiltration and Bedside Filtration in Thrombocytopenic Children with Malignant Diseases

Background: High-dose chemotherapy according to recent protocols causes a high rate of bone marrow aplasia. Platelet transfusions in immunocompromised patients need a consequent leukocyte depletion to prevent infections, alloimmunization and immunomodulation. Leukocyte depletion can either be done as inline filtration or as bedside filtration. To prevent graft-versus-host disease platelet concentrates are generally irradiated before transfusion. Methods: From June 1999 to May 2000 we administered 235 platelet concentrates in 38 pediatric patients with malignancies. The number of transfusions per patient varied from 1 to 28. In all patients the absolute platelet count was determined before and after transfusion. 118 concentrates were bedside-filtered, in 117 concentrates inline filtration was done. All concentrates were irradiated with 30 Gy before transfusion. In 116 platelet concentrates we detected the concentration before transfusion and calculated the corrected count increment (CCI). Half of these concentrates was bedside-filtered, the other half was inline-filtered. Results: The mean platelet count of the patients before transfusion was 13,500/µl and that after transfusion 52,000/µl. In the group treated with bedside-filtered concentrates the platelet count increased to 36,000/µl, and in the group treated with inline-filtered concentrates it rose to 68,000/µl. The difference is statistically significant (p < 0.0001). By detecting the platelet count in the concentrate directly after production and again after bedside filtration, a significant platelet loss could be shown. Conclusion: Inline-filtered platelet concentrates should be preferred for the transfusion in thrombocytopenic patients.